Bending stiffness (BS) is one of the two most important mechanical parameters of corrugated board. The second is edge crush resistance (ECT). Both are used in many analytical formulas to assess the load capacity of corrugated cardboard packaging. Therefore, the correct determination of bending stiffness is crucial in the design of corrugated board structures. This paper focuses on the analytical determination of BS based on the known parameters of the constituent papers and the geometry of the corrugated layers. The work analyzes in detail the dependence of the bending stiffness of an asymmetric, five-layer corrugated cardboard on the sample arrangement. A specimen bent so that the layers on the lower wave side are compressed has approximately 10% higher stiffness value. This is due to imperfections, which are particularly important in the case of compression of very thin liners. The study showed that imperfection at the level of a few microns causes noticeable drops in bending stiffness. The method has also been validated by means of experimental data from the literature and simple numerical finite element model (FEM). The obtained compliance of the computational model with the experimental model is very satisfactory. The work also included a critical discussion of the already published data and observations of other scientists in the field. A sign of the present times is the constant pursuit of the purchase of various merchandise, and thus the need for their packaging and safe transport, both in traditional forms of sale and e-commerce. The foremost desirable characteristics of the packaging are naturally adequate strength in relation to light weight and, in the interest of the natural environment, reusable, recyclable and biodegradable. Corrugated cardboard packaging perfectly meets all the above-mentioned requirements. Going further, the popularity of this type of packages is associated with the intensive development of a separate branch of industry and research. In view of the laws governing the free market, manufacturers strive for the most cost-effective solutions while maintaining the appropriate load-bearing capacity of cardboard packaging. The scientists, who have been developing for many years new methods to determine the material properties of the corrugated cardboard ,2 and arMuch of the research presented in the literature is devoted to the assessment of the load-bearing capacity of the cardboard. Analytical methods were described 70 years ago , where sExperimental methods are very common and frequently used to assess the load capacity of corrugated boards. The box compression test (BCT) and the edge crush test (ECT) are the most prevalent. The bending test (BNT), which allows to define the bending stiffness, the shear stiffness test (SST), the torsional stiffness test (TST) and humidity testing are also pertinent to the assessment of the mechanical properties of the cardboard box. Non-contact measurement methods are increasingly used to measure displacements or strains, even in routine laboratory tests. A technique that allows to gather the data from the outer surface of the specimen, in accordance with the measurement of the relative distances between pairs of points tracked across images acquired at various load values, is a video extensometry ,57 whichThe two most significant mechanical parameters of corrugated board are the bending stiffness (BS) and the edge crush resistance (ECT). They are exploited in analytical formulae to estimate the load-bearing capacity of corrugated cardboard boxes. The paper presents the analytical determination of BS of five-layer corrugated cardboard in four-point bending test basing on the known parameters of the constituent papers and the geometry of the corrugated layers. It was assumed that only flat layers, without the participation of corrugated layers are taken into account in the calculations. In the analytical model the presence of initial imperfections in compressed segments of the corrugated board was assumed. In addition, FEM numerical models have been built to validate the aforementioned assumptions. Two cases have been discussed—in the first one, both liners and fluting were taken into account to determine BS and in the second one, the stiffness of the corrugated layers was reduced to imitate a situation in which they are excluded from the computation. The method has also been validated by means of experimental data taken from the literature . The obtThe optimal selection of the arrangement of corrugated cardboard layers is fundamental for the load-bearing capacity of packages. For that reason, sensitivity analysis with respect to mechanical properties of liners and the flute geometric parameters was conducted to answer the question of which of the parameters have the greatest impact on BS. The main contribution of this study was the derivation of analytical relationships that explain the differences in the bending stiffness of asymmetrical corrugated boards when the layers on the B or E flute side are compressed.In the case of four-point bending of a sample with an asymmetric cross-section, especially when its cross-section consists of thin-walled faces (an example of such board is the corrugated cardboard), the dependence of the bending stiffness on the direction of the moment can be noticed. Using theoretical models as well as linear numerical models, this effect cannot be capture. This phenomenon belongs to the imperfection class of problems.Since in the four-point bending test, the mid-segment is bent with a constant moment M see  and all Thin-walled structures, when they undergo bending , have higher bending stiffness if the “stronger” part of the cross-section is compressed see a. On theIn our case, where a five-layer corrugated cardboard sample is tested, the stronger part of the cross-section is on the E-wave side. Therefore, from now on, the following description is used to distinguish two cases: (a) EB—compression of a part of the cross-section on the B wave side see b and (b)This study uses the results of the research presented in the work by Czechowski et al. . The autSince in the adopted calculation model (details will be discussed in the next subsection), only flat layers affect the machine direction (MD) bending stiffness, therefore only the MD stiffness moduli for liners only for all six boards are listed in The corrugated layers play the role of keeping the liners at the right distance to ensure adequate bending stiffness. The geometry of the separated, undulating layers is presented in In the geometrical description of the corrugated board, however, the thickness of the individual layers should also be taken into account, see Therefore, the total height of the corrugated cardboard 5EB is:As already mentioned, the measured thicknesses of the constituent papers see  and the It is assumed in this study that only liners are involved in bending in the MD, which means that fluting has only the role of supporting the liners in the correct position. Therefore, their tensile/compression and bending stiffnesses are negligible. In order to derive the model, first, all liners were segmented between the supporting wave crests in the corrugated layer see . PrelimiSince the five-layer corrugated board consists of three liners, three different segment lengths can be distinguished: i-th segment , it is possible to determine the longitudinal deflection in liners under compression or tension:i-th liner can be determined:For the known deflection i-th bending moment is:The If, instead of bending, the corrugated board cross-section is compressed or stretched in MD, the equation for compression/tensile stiffness can also be derived:The theoretical bending stiffness  as the product of the stiffness modulus in MD and the moment of inertia of liners only is:In order to normalize the theoretical values and the results of four-point bending tests, both values are divided by the width of the sample The presented derivation allows to explain the differences between the bending stiffness obtained from testing of the corrugated board sample placed with the E wave upwards or vice versa—B wave.In the first step, the theoretical assumption, in which only liners affect the stiffness of the entire section, was validated. For this purpose, two simple numerical models of a five-layer corrugated cardboard in a plane state  were built see . Both moIn the first model all layers were modeled according to their geometry and mechanical parameters, while in the second model, the stiffness of the corrugated layers was significantly reduced (by 100 times) to mimic a situation where only liners are active. The results are shown in FEM-1 (1-wave), number of nodes: 375, number of elements: 377;FEM-2 (2-waves), number of nodes: 746, number of elements: 754;FEM-3 (3-waves); number of nodes: 1118, number of elements: 1131;FEM-4 (4-waves); number of nodes: 1489, number of elements: 1508.In order to eliminate a possible error related to the discretization of numerical models, the influence of the number of finite elements and the number of waves in the model was also checked. The results are summarized in In the next step, the influence of imperfection amount on the bending stiffness in the analytical model was analyzed. The results for the parameter Because the presented analytical model takes into account the initial imperfections of compressed segments in the corrugated board, thus allows to distinguish between the bending stiffness of the corrugated board whether the E wave or the B wave is compressed. The bending stiffness not only decreases with the increase of the initial imperfection, but also the BS difference between the EB and BE increases as the imperfections increase see . In othek-factor, is 0.5% of The difference in bending stiffness between the EB and BE configurations can be as high as 25%. However, this applies to cross-sections in which the imperfection amounts to 1% of the initial length of the compressed segment, As the differences in the results summarized in All graphs in The results presented in the study were obtained while using derived analytical or numerical models, in which the experimental data presented in  were utiThe proposed analytical model does not take into account the corrugated layers in the calculation of the bending stiffness of the five-layer corrugated cardboard. Two numerical models were therefore built to validate this assumption. In the first of them, both flat and corrugated layers were used to determine BS. In the second one, the stiffness of the wavy layers was reduced to emulate a situation in which corrugated layers are excluded from the computation. For the comparison, the theoretical model was additionally employed, in which also just flat layers are considered in BS computation. All three models gave almost the same results presented in Since the presented model takes into account the influence of initial imperfections in the compressed segment of the corrugated board, the first attention was focused on determining the initial imperfection values.  22% see . In thisDue to the relatively large discrepancies between the calculated and measured values of bending stiffness, and due to the suspected measurement error or incorrect compilation of results in , the senIn this study, a detailed analysis of the effect of imperfections in thin-walled asymmetrical sections bent with a constant moment was carried out. The main contribution of this work was the derivation of analytical relationships that accurately describe the phenomenon of the difference in bending stiffness depending on the sign of the moment loading the asymmetric corrugated cardboard sample in machine direction. The paper showed that the applied analytical model satisfactorily reflects the real behavior of bent five-layer corrugated cardboard. The adopted simplifications did not affect the quality of the proposed solution, which was proved by a simple numerical model. Finally, the developed model was compared with the results of experimental research available in the literature. The obtained results are much closer to the experimental results than the results generated by other models available in the literature. Additionally, proposed model is very easy to implement, which makes it possible to use it in practice by cardboard manufacturers. This study also includes the sensitivity analysis, which indicates the most important parameters directly affecting the BS and, therefore, can be very helpful in more conscious design of optimal corrugated board.


Accurate classification tool for screening varieties with superior eating and cooking quality based on its pasting and starch structure properties is in demand to satisfy both consumers’ and farmers’ need. Here we showed the data related to the article entitled “Deploying viscosity and starch polymer properties to predict cooking and eating quality models: a novel breeding tool to predict texture”  This includes both routine quality  and rapid-visco analyzer (RVA) properties . 22.1n = 301) set of indica rice accession seed was selected according to their geographic distribution and genetic diversity, planted and grown during the dry season of 2014 at International Rice Research Institute (IRRI) under field conditions. After harvesting the grains and reducing it to 14% moisture content, they were dehulled  and milled . Some of the grains were converted to powdered  to undergo various biochemical analyses.A (2.23COOH (10% w/v) and 2%:0.2% KI-I2 solution (30% w/v) and the absorbance were measured at 620 nm in San++ Segmented Flow Analyser (SFA) system . The AC was quantified using a standard calibration curve from standard rice reference . These were run in triplicates.The AC, GT and GC have been routinely determined to identify the quality of rice grains. Traditionally, AC was determined through standard iodine colorimetric method (ISO 6647–2–2011) The GT was determined in triplicates using differential scanning calorimetry  GC was determined in triplicates using length measurement of the cold paste. Rice flour (100 mg) was mixed with ethanol (0.2 mL) containing 0.025% thymol blue and 0.2 M KOH (2 mL) and heated for 8 min in a boiling water bath. The mixture was cooled immediately in an ice-water bath and laid down horizontally for one hour 2.3The pasting properties of cooked rice were determined through the AACC method 61–02 The starch structure properties were determined using size exclusion chromatography (SEC) with Ultrahydrogel 250 column  2.4n = 110) from the rice diversity Indica panel was chosen and were cooked as prescribed by Cuevas et al. A set of samples . The distribution and variation of the data set was observed using Kernel density plots. Correlational analysis of all the measured variables  was also done to see the relationships of each variable from one another. Variables with p-value < 0.05 were considered not significant while values with |r| ≥ 0.70 were considered highly correlated.Preliminary clustering was done using the routine quality parameters . The clusterability of the data set was assessed at p-value < 0.05 using Hartigan's dip test for pairwise distances The RVA data were used to reclassify the dataset into a more comprehensive cooking quality ideotypes using the same clustering method. PCA was performed using the RVA data of all the samples to see if there is distinct separation between clusters. The scores were obtained and plotted in a bi-plot to see the distinction between the groups created from the clustering. The loadings of each variable were also obtained to see which variable is correlated to each cluster. The created classes or clusters were concluded as the cooking and eating quality ideotypes for the selected lines. Each ideotype were sub-clustered using starch SEC data via AGNES and the created classes were identified as the subclass of each ideotype.The authors declare no known competing financial interests or personal relationships which have or could be perceived to have influenced the work reported in this article.


Several emerging areas like the Internet of Things, sensor networks, healthcare and distributed networks feature resource-constrained devices that share secure and privacy-preserving data to accomplish some goal. The majority of standard cryptographic algorithms do not fit with these constrained devices due to heavy cryptographic components. In this paper, a new block cipher, BRISK, is proposed with a block size of 32-bit. The cipher design is straightforward due to simple round operations, and these operations can be efficiently run in hardware and suitable for software. Another major concept used with this cipher is dynamism during encryption for each session; that is, instead of using the same encryption algorithm, participants use different ciphers for each session. Professor Lars R. Knudsen initially proposed dynamic encryption in 2015, where the sender picks a cipher from a large pool of ciphers to encrypt the data and send it along with the encrypted message. The receiver does not know about the encryption technique used before receiving the cipher along with the message. However, in the proposed algorithm, instead of choosing a new cipher, the process uses the same cipher for each session, but varies the cipher specifications from a given small pool, e.g., the number of rounds, cipher components, etc. Therefore, the dynamism concept is used here in a different way. Computer devices nowadays are continuously developing, and the performance of these new devices is better than before with powerful resources. Portable devices like tablets and smartphones have replaced basic phones and allow several advanced features similar to a computer. Existing standard cryptographic algorithms were designed to meet the requirements of desktop/server computers. In recent years, the Internet of Things has become popular. These resource-constrained devices are increasingly used in various applications, such as wireless sensor networks and Radio Frequency Identification (RFID). These devices have minimal memory and power, and computing capability. Providing security to these devices with lightweight encryption techniques is a major challenge nowadays. Lightweight cryptography  providesAn RFID system mainly consists of three components: readers, tags and a back-end system see . A tag mPassive Tags: Passive tags absorb the power from radio waves, and they do not have any battery. The absorbed power by tag is used to power the internal circuit and make communication through the antenna.Active Tags: In general, active tags are more expensive due to additional expenses on manufactures. Active tags contain the power source onboard. This power source could be a battery that provides power to the antenna and the internal circuit.Semi-Active Tags: Semi-active tags contain a battery to give power to the internal circuit, but this power is not used for communication through the antenna. Such tags retain the advantage of both active and passive tags and remove several disadvantages from both. The power can be saved for a long time.There are several types of tags available see  based onHealthcare: RFID has several applications in healthcare such as patient tracking, patient monitoring, patient drug compliance, patient monitoring, etc.Contact-less Payments: Many companies such as MasterCard, VISA, American Express etc., use RFID technology for contactless payments.Passport: Several countries like the United States, Japan, and Norway incorporate RFID tags in passports that store traveller history, photographs and other important information.Toll Road Payments: Several highway toll booths use RFID technology where vehicles do not stop on the toll booth but directly passes through an E-Z pass lane, and the toll is automatically deducted.Product Tracking: RFID tags are mostly used in tracking the inventory throughout the supply chain. These RFID tags are used as a cost-effective way to track products and used as a substitute for the barcode.The radio-frequency identification (RFID) system will soon replace the barcode system completely as it is considered the next generation of a barcode. The tags used in RFID can be divided into two types, read-only tags: information stored in this cannot be changed later, and read-write tags: information stored in this can be read or write, but they are more expensive than read-only tags. RFID has several applications in real life, including passports, electronic IDs, door locks, supply chains, electronic payments, etc. Some of the application is given as follows:cryptology is related to encrypting information with the help of encryption algorithms and also analysing these algorithms in terms of security margin. Therefore, in general, the cryptology is divided into two parts: cryptography and cryptanalysis  splits into two parts: tion see , the senperformance, security and cost. In block ciphers, the cost-performance trade-off is provided by hardware architecture, the key length of the cipher provides the security-cost trade-off while the number of rounds provides the security-performance trade-off. However, these three properties create a trilemma, and it is only possible to obtain the only pair of goals out of three. In general, there are three basic approaches to design encryption algorithms suitable for lightweight applications as RFID tags:Design new ciphers with a goal of low costs for hardware implementation.Slightly modify standard algorithms and make it suitable lightweight applications.Optimise the implementation cost of standard and trusted algorithms.The biggest challenge for designers of lightweight algorithms is to make a balance between three things, namely: One major problem of passive RFID applications is a very small power source. The power consumption for lightweight algorithms should not be more than 15 Area: This requirement is generally measured in Cycle: It represents the number of clock cycles to compute or read the results. A parallel block cipher implementation performs any number of encryption/decryption round operation within one clock cycle. On the other hand, in round-wise implementation, one round function is performed in one cycle.Time: Time required for a certain operation can be calculated by taking the ratio of cycles and operating frequency and mathematically can be expressed as Power Power consumption is measured in microwatts [P in CMOS devices.C is circuit capacitance, N is switching activity, f is operating frequency.In the above equation, Throughput: Throughput is the rate at which output can be produced with respect to time. Throughput is measured in bits per second [Efficiency: The efficiency is the ratio of throughput and area, and mathematically can be expressed as Another major issue with lightweight applications is low storage. Each cipher has an internal state: cipher state and key state. Ciphers use plaintext to initialise the state, and at this phase, it is called a cipher state while it is modified each round with the action of key, and therefore called key state onwards. The internal state of the cipher is generally stored at each round. In general, for the desktop environment, RAM and ROM are available to store the data, but in the case of RFID tags, it is not possible, and values are stored in registers. Block ciphers generally have a fixed number of rounds, and a large number of rounds requires more memory, as we know that cipher states are saved in the memory after each round. However, in this paper, a dynamic number of rounds concept is used, and therefore, very small applications can also run the block cipher by using a small number of rounds. The recently proposed lightweight block ciphers SPECK and SIMON , by the Another lightweight block cipher, LEA , was desThe dynamic encryption  concept In this article, a lightweight block cipher BRISK has been proposed. It supports block sizes of 32-bit, where the block is divided into two of word size 16-bit. BRISK has the following features.BRISK is a symmetric block cipher. This implies that the same key is used for encryption as well as decryption.BRISK supports two versions of the cipher, and both version use two different types of S-Boxes.BRISK is suitable for hardware as well as software. The cipher is word-oriented, which means at a time operations are performed on words of data.BRISK follows dynamism in encryption and decryption. For each session of data encryption, it uses either S-BoxBRISK has a key length of 80-bits that can be divided into 5 subkeys used for the first 5 rounds, and after that, it generates other round keys from the main key.BRISK has a very simple design and is very easy to implement. The simple structure also allows easy cryptanalysis of the cipher. It has a low memory requirement, and therefore can be easily implemented on resource-constrained devices with small memory.The following notations see  were usen, where n has the value of 16-bit. So, the cipher takes plaintext input that is divided into two words and produces two-word ciphertext output with the same size. These block sizes are suitable for different applications like the RFID system. The number of rounds depends on the computational power of devices and security requirements. BRISK uses the key length of 80-bit divided into 5 subkeys for initial rounds and then generates new keys from the previous keys using the round function of BRISK. The cipher has both layers of operations that satisfy the confusion and diffusion property of any cipher. For confusion, cipher uses four S-Boxes of size 4-bit, and for diffusion, it uses a permutation layer of 16-bit. The recommended number of rounds for the cipher is 32. However, it can be changed using the dynamism concept and depends on the security requirement of the IoT devices. Based on the hamming weight of the key, cipher chooses which component has to be used. For example, if there are an odd number of 1s in the binary value of key then S-BoxBRISK is a block cipher from the family of Feistel ciphers. BRISK has a block size of bitwise XOR, ⊕;S;Substitution-Box P.Permutation-Box The algorithm mainly has three components: encryption, decryption and key expansion. The round function of the cipher is shown in The round function of BRISK is a map oxes see  for non-For permutation layer purpose, two different permutations  and depends on a particular library. However, this cipher is based on dynamic design and the number of rounds or operation changes throughout the implementation and, therefore, instead of writing the exact area, the maximum area is calculated with the highest number of rounds. Note that the user can use a small number of rounds, and in that case, the area will be smaller. The result is mainly based on the ARM standard library for IBM 8RF and The hardware implementation comparison is shown in P and Differential Cryptanalysis: To analyse the security margin of the cipher, the most powerful attack differential cryptanalysis is applied to the cipher. Differential cryptanalysis was introduced by Biham and Shamir in 1990 for the cryptanalysis of cipher FEAL . This teunds see .p is called differential characteristics . An ideal cipher should follow random distribution for all input/output pairs and the probability of differential path for the n-bit cipher is The sequence of differences through several rounds lity see .For an input difference of the non-linear layer, there could be several possible outputs with different probabilities. The attacker needs to find higher probability output. For such calculations, a difference distribution table (DDT) of the non-linear component is required to generate based on the non-linear layer’s specifications. This table shows the probability of each output for a certain input. Generating such a table for S-boxes that has mainly the size of 8- or 4-bit is possible. The size of difference distribution table see  for a 8-i et al. ,42 preseThe cipher is analysed with differential cryptanalysis using the nested tree search method, and the result is presented in Linear Cryptanalysis: Linear cryptanalysis  is anothhers see . The heuhers see .(4)ϵ1,2Cipher is also analysed with linear cryptanalysis using the nested tree search method, and the result is presented in This paper presents an encryption algorithm that is mainly suitable for resource-constrained devices such as the Internet of Things. The cipher uses the concept of dynamism and uses two different cipher components to encrypt the data. For each session, the number of rounds can also be different. However, at a time (one session), only one cipher is used, and the attacker is not aware of which cipher is exactly used. Due to the dynamism concept, the cipher provides an extra layer of security. The cipher is also safe against the most powerful cryptanalytic tool called linear and differential cryptanalysis. Cryptanalysis results show that the cipher has enough security margin against these two attacks when using the recommended rounds.


The main principles of the present medial collateral ligament (MCL) reconstruction techniques are (1) to approximate the natural anatomy and (2) to restore the main passive restraining structures in anteromedial and posteromedial knee instability. Therefore, we describe a technique using a flat tendon graft instead of tubular grafts with point-to-point bone fixation. Moreover, we address the deep MCL, a relevant restraint to anteromedial instability. >This video shows two options of double-strand medial collateral ligament (MCL) reconstruction techniques to either perform an anteromedial or posteromedial stabilization using a flat graft with a thin oval-shaped insertion on the femur, a wide insertion of the oblique fibers close to the tibial plateau, and a large distal insertion of the superficial medial collateral ligament (sMCL) part, at the level of the pes anserinus. This reconstruction technique can be performed using autografts like semitendinosus tendon or peroneus split graft or allografts like semitendinosus tendon, peroneus longus tendon, or tibialis posterior tendon. “Round” tendons can be easily converted to a flat shape by dissecting the graft to half of its diameter and afterward squeezing it with a blunt rasp without any negative impact on mechanical properties of the graft. The graft is then folded once in 1/3 to 2/3 at an angle of about 45°, with the short arm being below and looking either anterior or posterior, depending on the aim of reconstruction. After suture fixation of the proximal end using Krackow stitches, the graft shows a permanent angle and flat shape. After exposing the femoral insertion of the MCL, a Beath Pin is drilled in the center of the insertion area through the lateral cortex. After overdrilling the k-wire and removing the medial cortex with a luer, the flat femoral socket parallel to the joint line in extension is established using a flat dilator  matching the graft size (S.M). Alternatively, a round femoral tunnel is acceptable, especially in complex reconstructions and lack of time. In this case, the Beath Pin is positioned slightly more posterior in the MCL insertion area and overdrilled with a drill bit matching the graft size to a depth of 30 mm. The graft is inserted with the correct orientation of the two arms into the femoral tunnel, but not yet fixed. First, the short arm is attached to the tibia, either in the anteromedial ligament (AML) or posterior oblique ligament (POL) position using two suture anchors . Then the graft is fixed under tension in the femoral tunnel, either using the fixation button for the flat tunnel or a screw for the round tunnel. Finally, the long arm is fixed as sMCL to the tibia at the level of the pes anserinus, again using two suture anchors close to extension. Now, the knee is fully extended and is flexed at least to 100° to check for free range of motion. It is important for providing support against valgus stress, rotational forces, and anterior translational forces on the tibia. Injuries to that ligament are the most common injuries to the knee joint.,,,Consequently, the MCL is a complex ligament to be reconstructed satisfactorily.The patient is positioned supine with the knee slightly flexed. Positioning should allow the patient to hang his or her leg down on the lateral side to perform at least a diagnostic arthroscopy and check for the reduction of the medial compartment. A thigh tourniquet is applied, and knee motion between 0° and 100° flexion should be possible. In this case, we prefer not to use a leg holder. For unlimited access to the operated leg’s medial side, the contralateral leg is put to lithotomy position.Autografts, including the semitendinosus tendon (SemiT) and the anterior half of the peroneus longus tendon, and various allografts can be used, according to the individual case and surgeon’s preference. However, the SemiT is an important dynamic stabilizer against valgus close to extension.1.The tendon length is checked on a preparation board, which should be 22 cm or more depending on the size of the knee.2.The muscle is removed, and the tendon is placed with the muscular insertion facing upward.3.At the end of the muscular insertion site, the tendon gets tubular. The tubular part of the tendon is flattened by dissecting the tendon to half of its diameter with a knife A and smo4.The tendon is then folded at an angle of about 45° C over a 5.The folded end of the graft is prepared using an interlocking suturing technique (Krackow-stitch) with a no. 2 nonabsorbable suture  and threaded as a pulley system into a fixation button .6.The length of the femoral insertion (about 2 cm) should be marked on the graft.1.A skin incision of about 12 cm in length is made from the medial epicondyle A to the 2.A Beath Pin is drilled in the middle of the femoral insertion of the sMCL through the lateral cortex . In case3.Then the guidewire is over-reamed with a 4.5-mm drill bit through the lateral cortex B.4.Key Maneuver: The knee is brought to full extension, and the tunnel orientation is marked parallel to the tibial plateau. Then the medial cortex is removed in the insertion area using a luer  to a flat graft by dissecting the tendon to the half of its diameter with a knife, and smoothing it to a flat shape is technically feasible. According to Domnick et al.,For graft choice in MCL reconstruction, one should take into account that the hamstring tendons and especially the semitendinosus tendon are important dynamic stabilizers against valgus rotation close to extension,The most decisive limitation of this technique is the number of anchors needed to reproduce the wide insertion areas, which adds costs, the increased surgical time, and the need for special instrumentations for creating a rectangular tunnel. Especially in complex ligament surgery when time becomes an issue, as a compromise, the rectangular tunnel on the femur may be replaced by a conventional round tunnel using a cannulated drill and interference screw fixation still using a flat graft.The flat reconstruction technique for medial instability proved feasible and effective clinically and may be associated with biomechanical and biological advantages to the commonly used techniques with tubular grafts.


Intraoperative assessment of graft patency is pivotal for successful coronary revascularization. In the present study we aimed to propose a new, easy to perform tool to assess anastomotic quality intraoperatively, and to investigate its potential reliability in predicting early graft failure. Intraoperative graft flowmetry of 63 consecutive patients undergoing CABG were prospectively collected. Transit time flowmetry and its derivatives were recorded. Coronary resistances were calculated according to Hagen–Poiseuille equation both during cardioplegic arrest and after withdrawal from cardiopulmonary bypass. Angiographic evidence of graft occlusion at follow-up was cross-checked with intraoperative recordings. After a mean follow-up of 10.4 ± 6.0 months, 22 grafts were studied, and occlusion was documented in five (22.7%). Occluded grafts showed lower flows and higher resistances recorded during aortic cross-clamping. Coronary resistances, recorded during aortic cross-clamping, greater than 2.0 mmHg/mL/min, showed a sensitivity of 80% and a specificity of 100% to predict graft failure. We propose the routine recording of coronary resistances during aortic cross-clamping as an additional tool to overcome the acknowledged limitation of TTF to predict graft occlusion at 1 year. Intraoperative assessment of graft patency is pivotal for successful coronary revascularization. As early graft failure is usually consequential to technical faults , current guidelines suggest transit-time flow (TTF) measurements to assess intraoperative graft patency .Several studies have aimed to discriminate the most reliable cut-off for the many available TTF derived parameters, but no one has demonstrated a clear reliability to predict quality and long-term graft patency ,3,4.In 1999, Belboul and colleagues demonstrated that coronary vascular resistances can be calculated intraoperatively using TTF . This meIn the present study we aimed to propose a new, easy to perform tool to assess anastomotic quality intraoperatively and to investigate its potential reliability in predicting early graft failure.This is a retrospective analysis of prospectively collected data. From December 2019 to April 2020, intraoperative graft flowmetry of all consecutive grafts were collected in an institutional ad-hoc database. Surgery has always been performed by the same experienced surgeons  on normothermic cardiopulmonary bypass with aortic cross-clamping an intermittent hyperkaliemic blood cardioplegia. Inclusion criteria for the present analysis were age ≥18 years, on pump surgery with aortic cross-clamp, first-time surgery. Patients undergoing off-pump coronary revascularization, emergency procedures and in-hospital deaths were excluded. Sixty-four patients fulfilled the inclusion criteria. One patient (1.6%) died of pneumonia during hospitalization and was thus excluded from the study. Accordingly, 63 consecutive patients were part of the present analysis, accounting for a total of 113 grafts. Informed consent for the operation and for subsequent follow-up for research purposes was obtained from each patient upon hospital admission. The study protocol conforms to the ethical guidelines of the 1975 Declaration of Helsinki.Graft function was assessed under stable hemodynamic conditions, generally at 30 min after protamine administration. Flowmetry of the grafts was performed with a transit-time flowmeter . Different probe sizes  were available to avoid distortion or compression of grafts. Mean flow (mL/min) and pulsatility index (PI) were obtained directly from the flowmeter. Mean arterial and central venous pressures were recorded as well.For the specific aim of this study, flow (mL/min) and pressure drop on the cardioplegic line during selective cardioplegia administration in the venous grafts has been recorded; for homogeneity of data collection, flows were recorded at a standardized pressure of 100 mmHg . Left inCoronary resistances (CR) were calculated according to the Hagen–Poiseuille equation as CR = (P2 − P1)/Q.When CR were calculated after withdrawal from cardiopulmonary bypass, P2 is the mean arterial pressure in mmHg, P1 is the central venous pressure in mmHg, and Q is the mean flow (in mL/min) through the graft calculated during TTF analysis . TransitWhen CR are calculated during aortic cross-clamping, differences should be made between venous and arterial grafts. Indeed, for venous grafts, P2 is the pressure drop in the cardioplegic line and Q is the flow of cardioplegia administered selectively in that graft; in the case of mammary artery grafts, P2 is the mean systemic perfusion pressure and Q is the mean flow recorded with TTF probes. In all these cases, P1 is considered equal to 0, as all venous blood return is drained to the reservoir .Angiographic data retrieved from patients undergoing coronary angiography during the first postoperative year, for onset of angina-like symptoms or instrumental signs of ischemia, were cross-checked with intraoperative flow recordings. A FizzGibbon grade greater than A was coded as angiographic occlusion.The primary endpoints of this study were the assessment of the safety and technical feasibility to record intraoperative graft flow-derived parameters during aortic cross-clamp, as an alternative tool to beating heart transit-time flowmetry. The secondary endpoint was the identification of appropriate cut-off values to predict early graft failure during follow-up.Continuous variables are expressed as means and standard deviation, whereas categorical variables are reported as counts and percentages.t-test, Mann–Whitney U test and chi-square test.Differences in flow-derived parameters between occluded and patent grafts were assessed with an independent sample The univariate association between CR-cardioplegia, CR-protamine, mean flow . An AUC ≥0.8 was considered acceptable. For the specific purpose of our analysis, the DeLong test was used to determine if the differences between the AUCs were statistically significant from CR-cardioplegia . The YouAll statistical analyses were performed using SAS version 9.4 statistical software  and R version 3.6.1   with theBaseline characteristics are listed in The mean number of grafts per patient was 2.3 ± 1.2. Flow-derived parameters, stratified per graft type and grafted territory are better described in When the primary safety endpoint is considered, we did not observe any intraoperative adverse event related to the selective administration of cardioplegia in the venous grafts. When the feasibility endpoint is concerned, TTF has been routinely applied to all mammary artery grafts during cross-clamping time, with recordings coherent to what has been observed in case of venous grafts.After a mean follow-up of 10.4 ± 6.0 months, two patients died (3.2%) , 51 were asymptomatic and 10 underwent coronary angiography for onset of angina-like symptoms or instrumental signs of ischemia. Overall, 22 grafts were studied, and occlusion was documented in five (22.7%—4 saphenous vein grafts and 1 LIMA graft).When intraoperative flow measurements were retrieved, occluded grafts showed lower flows and higher resistances recorded during aortic cross-clamping, whereas negligible differences could be observed among TTF-derived parameters recorded after withdrawal from CPB .p = 0.0014) with none of the other recorded or derived parameters reaching statistical significance . We identified 2.0 mmHg/mL/min as the most appropriate cut-off, with a sensitivity of 80% and a specificity of 100%  demonstrated an adequate discriminatory ability for the prediction of graft failure , being h of 100% .In the present study we observed that coronary resistances can be easily assessed intraoperatively, and can provide useful adjunctive knowledge on the anastomotic graft quality, beside already established technologies, such as TTF. Furthermore, intraoperative assessment of coronary resistances, calculated during aortic cross-clamping time, may predict graft patency at mid-term follow-up.Intraoperative assessment of graft patency during CABG is mandatory, as it allows the detection and correction of any graft failure. Among all currently available techniques, TTF is one of the most applied methods. Although its use is supported by current guidelines , severalInvestigating the CR during cardioplegic arrest provides several interesting pieces of knowledge for the operating surgeon. Indeed, from a physiological perspective, CR has three components: (1) a basal low resistance in the plegic heart, when vessels are maximally dilated and cannot contract; (2) an added basal resistance when vessels have tone; (3) a supplementary phasic resistance during ventricular contraction . Therefop = 0.01) [Although Belboul and coworkers set the benchmark for the methodology used in the present study, information regarding the late fate of the implanted grafts is missing . To the  = 0.01) . Convers = 0.01) . In our Our study has several limitations. First, the small number of patients included prevent firm conclusions from being drawn on this topic. Secondly, it has been retrospectively designed. Thirdly, it is not a randomized controlled trial. Finally, some patient-related risk factors  are missing, and thus some intraoperative biases might not have been adequately addressed in our models. Future prospective studies, specifically designed to control all patients with computed tomographic coronary angiography, will allow the inclusion of more patients in the analysis and acquire more details on the predictive power of our index.Conversely, the single-centre design guarantees the uniformity of data collection and of surgical technique.Transit time flowmetry remains the most common method used for the intraoperative assessment of the quality of grafts. Coronary resistances are easy to derive intraoperatively and help to identify graft at potential risk of early failure. We propose the routine recording of coronary resistances during aortic cross-clamping as an additional tool to overcome the acknowledged limitation of TTF to predict graft occlusion at 1 year. LIMA-LAD is not a limitation for measurement during aortic cross-clamping.


Regarding joint stiffness, we found no significant difference between the pre- and post-dermal suction values . These findings suggest that dermal suction increases passive muscle stiffness and has a limited impact on passive joint stiffness.The aim of the present study was to examine the acute effects of dermal suction on the passive mechanical properties of specific muscles and joints. Dermal suction was applied to the calves of 24 subjects. Passive plantar flexion torque was measured with the right knee fully extended and the right ankle positioned at 20°, 10°, 0°, and −10° angles, where 0° represents the ankle neutral position, and positive values correspond to the plantar flexion angle. The shear wave velocity (SWV) (m/s) of the medial gastrocnemius was measured in the same position using ultrasound shear wave elastography. The relationship between the joint angle and passive torque at each 10° angle was defined as passive joint stiffness (Nm/°). Passive muscle and joint stiffness were measured immediately before and after the dermal suction protocol. When the ankle joint was positioned at 20° ( Flexibility is a component of physical fitness, and various studies have been conducted to research ways to improve flexibility . There aAs above-mentioned, previous studies evaluated the influence of cupping therapy on joint flexibility using joint ROM as an index of joint flexibility ,6,7,8,9.Ultrasound elastography is a technique that can localize stiffness or hardness of a muscle . Muscle Recently, to examine whether cupping therapy could change mechanical properties of muscle, Jan et al.  investigWe enrolled 12 men and 12 women who were recreationally active in this study. None of the subjects reported any ongoing neuromuscular diseases or musculoskeletal injuries specific to the ankle joint. In addition, no subject complained about poor physical condition on the measurement day. The age and physical characteristics of the subjects are shown in SD: standard deviation, CI: confidence interval, lb: lower bound, ub: upper bound, BMI: body mass index.This study was a single-arm study designed to examine the acute effects of dermal suction on passive muscle and joint stiffness. After measuring ankle joint stiffness using a dynamometer and the passive stiffness of the medial head of the gastrocnemius of the right leg using ultrasound shear wave elastography, dermal suction was applied to the right calf of the subjects for 8 min, and the same measurements were taken immediately after the application.Passive plantar flexion torque was measured using a specially designed dynamometer , which has previously been used by other investigators to measure the plantar flexion torque ,17,18. TDuring the measurement of passive ankle joint stiffness, passive muscle stiffness was simultaneously measured in the same position . The pasDermal suction was performed using Medicell  , which ct-test. The level of significance was set at P < 0.05. We calculated the 95% confidence interval (CI) for the difference between the mean values. partial η2 was calculated as the effect size for the main effect and interaction in the two-way ANOVA where 0.01, 0.06, and 0.14 indicated small, medium, and high effects [r) for the post hoc test was calculated [r was classified as small (≤0.10 and <0.30), medium (≤0.30 and <0.50), and large (≤0.50) [Statistical analyses were performed using SPSS statistics . In order to verify whether there was a difference in the SWV and the joint stiffness due to dermal suction and changes in the joint angles, a two-way repeated measures analysis of variance (ANOVA) was performed, where the independent variables were time (before and after) and the joint angles, and the dependent variables were the SWV and joint stiffness. When appropriate, post hoc comparisons were performed using the Bonferroni-corrected  effects . Additiolculated . Effect  (≤0.50) .F value = 11.682, P = 0.002, partial η2 = 0.337) and joint angle , and showed a significant interaction between the time and the joint angle . The post hoc comparison revealed that the SWV increased when the ankle joint was dorsiflexed . Post hoc comparison also showed that excluding the ankle position at 0°, SWV was higher after dermal suction than before dermal suction . A marginally significant difference was found between the pre- and post-dermal suction SWV values at 0° .No participant dropped out from the study during the entire study duration. The SWV of the MG for each joint angle before and after dermal suction is shown in F value = 10.091, P < 0.001, partial η2 = 0.305). In contrast, the main effect of time  and interaction between the time and the joint angle  were not significant. The post hoc comparison demonstrated that joint stiffness at 0° to −10° was higher than that at 20° to 10°  and 10° to 0° . There was no significant difference between the joint stiffness at 20° to 10° and 10° to 0° . We carried out a post hoc test to calculate the power (1-β) by setting an α level of 0.05, the effect size for the main effects of time in SWV, and the sample size using G*Power (version 3.1.9.3). As a result, the power was 1.00.The passive ankle joint stiffness before and after dermal suction is demonstrated in In the present study, we compared the passive muscle stiffness of the MG and passive ankle joint stiffness before and after dermal suction to verify the hypothesis that dermal suction decreases passive muscle stiffness and increases passive joint flexibility. Based on the results, two main findings were noted: (a) dermal suction significantly increased passive muscle stiffness; and (b) it had no significant effect on passive joint stiffness.In contrast to our hypothesis, the current results showed a significant acute increase in the SWV after dermal suction, indicating that dermal suction acutely increases muscle stiffness. A possible explanation for the observed acute increase in muscle stiffness following dermal suction is that the suction may result in an increase in intramuscular water content. Yoshitake et al.  investigP > 0.05). These findings, however, do not lead to the conclusion that the intramuscular water content did not affect our results. In the current study, muscle thickness was only measured in one slice. The changes in muscle thickness induced by resistance training have been reported to be different within the same muscle [This phenomenon may manifest as an increase in the muscle volume after dermal suction. Thus, we additionally calculated the muscle thickness of the MG before and after dermal suction. The results showed no significant change in muscle thickness (cm) . Therefore, it should be noted that this study only investigated the immediate effects of dermal suction. Third, we did not investigate the water intake of the subjects. We noted that intramuscular water content may be related to the increase in muscle stiffness after dermal suction in this study. Further experiments with controlled water intake conditions should be undertaken. Fourth, while the increase in muscle stiffness could be related to the increase in intramuscular water content, the actual mechanism underlying increased muscle stiffness is unclear. Further research including various methodologies such as biochemical or physiological analyses are needed to obtain detailed information on the effects of dermal suction on the mechanical properties of muscle.The findings presented here provide information about the effects of dermal suction on the mechanical properties of muscle and joint. Our results suggest that dermal suction increases passive muscle stiffness and has a limited impact on passive joint stiffness. These results might indicate that dermal suction is useful when physical therapists or conditioning professionals are trying to increase muscle stiffness in their clinical practice. However, how muscles or joints are affected by dermal suction remains unclear. Well-constructed scientific research detailing the mechanism of action of dermal suction would help increase our understanding of this treatment.


One of the examples of physical starch modifications is the retention of a starch suspension in water having a temperature slightly lower than the pasting temperature . The aim of this study was to investigate the effect of the annealing process performed at various temperatures as the first stage of starch modification. The annealed starch preparations were then esterified using acetic acid anhydride. Finally, the annealed and acetylated starch preparations were determined for their properties. The annealing of starch before acetylation triggered changes in the properties of the modified preparations. It contributed to a higher degree of starch substitution with acetic acid residues and to the increased swelling power of starch. Both these properties were also affected by the annealing temperature. The highest resistance to amylolysis was found in the case of the starch preparation annealed at 53.5 °C and acetylated. The double modification involving annealing and acetylation processes increased the onset and end pasting temperatures compared to the acetylation alone. Similar observations were made for the consistency coefficient and yield point. Starch is a natural plant raw material applicable in many branches of the industry, which usually makes use of its modified preparations, i.e., starch subjected to various treatments to modify its properties. The methods of starch modification can be divided into physical, chemical, and enzymatic ones ,2,3,4,5,Its goal is to increase the mobility of molecules; however, without making them turn into the gelatinized form. The annealing process results in the hydration of starch granules, which firstly affects their amorphous and then crystalline regions. Particle mobility increases by analogy, which intensifies the interactions between starch chains and leads to chain ordering. A homogeneous and stable structure of the entire granule is then developed. The swelling of the granule is limited and its form is preserved ,11,12,13The effects of annealing on starch pasting characteristics determined with the DSC are well described in scientific literature  and inclAnnealed starch has found multiple applications in the industry ,17. Due The scientific literature indicates the feasibility of performing the annealing process together with other modifications. Zhong et al.  investigAcetylation is one of the methods of chemical modification that may be coupled with physical processes. It is usually performed using starch acetate (E1420) that is of great importance to the food industry  and can Preparations of acetylated annealed potato starch may be deployed for a slow release of a therapeutic substance . The proThe experimental material included Superior Standard potato starch  produced in 2020.Differential scanning calorimetry (DSC) was employed to determine the pasting temperature of potato starch, which reached 62.79 °C.A suspension was prepared from native potato starch, which contained 10 g of starch per 100 g of the solution. The prepared suspension was kept for 48 h at temperatures of 51.0, 53.5, 56.0, 58.5, or 61 °C, under continuous stirring. Afterward, starch was rinsed three times with 5-L portions of distilled water. Starch precipitate was separated from the suspension using a stratos flow-centrifuge , then dried at 30 °C for 24 h, ground, and sieved through a screen with mesh size of 400 μm.Acetylation was applied to the annealed starch preparations and to native potato starch. Starch dry matter (200 g) and water (1000 g) were placed in a reactor and mixed to achieve a homogenous suspension, the pH value of which was adjusted to pH 8–9 using a 0.5 M NaOH solution. Afterward, 26 mL of acetic acid anhydride were instilled to the starch suspension under continuous stirring. At the same time, the 0.5 M NaOH solution was instilled into the solution to maintain the pH value of the reaction mixture at pH 8–9. Once the whole portion of the anhydride had been added, the mixture was stirred for 15 min and then acidified to pH 5.2–5.6 using a 2.8 M HCl solution. Afterward, the suspension was filtered through a Buchner funnel to enable starch precipitation. The resultant modified starch was rinsed with water until the excess of the reagent had been removed. Then, the preparations were dried at 30 °C for 24 h, ground, and sieved through a screen with mesh size of 400 μm.Acetylated starch (10 g) was weighed and transferred to a 300 mL conical flask using 65 mL of distilled water. Starch and water were mixed, and then 2–3 drops of phenolphthalein and also 0.1 M NaOH solution were instilled to the mixture until it developed a light pink color which sustained for 1 min. Next, 25 mL of a 0.5 M NaOH solution were added to the mixture, which was then shaken for 35 min. Afterward, the mixture was titrated with a standard HCl solution [P0—volume of a standard HCl solution used to titrate 25 mL of a 0.5 M NaOH solution [mL].WP—volume of a standard HCl solution used to titrate the sample [mL].kN—acid titer.SM—grams of starch dry matter in the sample.The percentage of acetylation A was computed acc. to the following formula:The degree of acetylation was computed acc. to the following formula:The starch preparation (0.3 g) was placed in a 4 mL test tube, to which 2.5 mL of distilled water were added. The content of the flask was conditioned at a temperature of 20 °C for 10 min. Afterward, the samples were centrifuged using an MPW-55 type laboratory centrifuge  at the speed of 5000 rpm and a temperature of 20 °C for 10 min. After centrifugation, the supernatant was collected, and the precipitate left in the test tubes was weighed .WM—weight of the precipitate after centrifugationPM—weight of the sample.Working swelling power was calculated using the following formula:A 0.72 g/100 g aqueous suspension was prepared from 38 g of starch. It was then heated to the boiling point, cooled, and then the volume of evaporated water was completed. Afterward, 34 mL of an acetate buffer were added, and the sample was placed in a water bath at a temperature of 37 °C. To enable hydrolysis, 4 mL of amyloglucosidase were added; its concentration was adjusted so as to ensure the complete saccharification of gelatinized native potato starch after 120 min of the process. After 120 min, 10 μL of the sample were collected and transferred into a test tube with 1 mL of a reagent for glucose concentration measurement  containing glucose oxidase and peroxidase. The content of the flask was mixed and incubated at a temperature of 20 °C for 15 min. Then, absorbance was measured at a wavelength of λ = 500 nm using a CECIL CE 2010 colorimeter . The measurement results were compared to those achieved for a control sample prepared in an analogous way but without the starch preparation. The absorbance value obtained was compared with the standard curve plotted based on the read outs of absorbance of solutions with a known glucose concentration .R—resistance of starch preparations to amyloglucosidase action (g/100 g).X—content of glucose read out from the standard curve (mg).Resistance of the starch preparations was computed using the following formula:Determination was performed using a DSC 822E differential scanning calorimeteter  . A 10 g Analyses were conducted using an RS 6000 oscillating-rotating viscosimeter Haake  for 5 g/100 g starch suspensions that were heated at 96 °C for 30 min under continuous stirring .−1. A hot paste was placed in a system of coaxial cylinders (Z38ALtype) of the RS 100 rheometer, then cooled, and relaxed at the measurement temperature for 15 min. The flow curves plotted were described using the following equations:τ—shear stress (Pa)n)K—consistency coefficient (Pa·s−1)ẏ—shear rate (sn—flow indexoc—yield point (Pa)τ c—Casson’s plastic viscosity (Pa·(s))ƞFlow curves were plotted for the prepared pastes, at a measurement temperature of 50 °C and a shear rate of 1–300 sResults were statistically analyzed using the Statistica 13.0 PL software package. Based on statistical computations , values of the least significant differences and standard deviation were calculated, and equations of flow curves were determined. For statistical evaluation, the results were subjected to one-way analysis of variance at a significance level of 0.05. Values of the least significant difference (LSD) between the means were computed using the Duncan’s test at a significance level of 0.05 .The analysis of study results allows concluding that the increased water absorption capacity indicates debilitation of the association potential of polymer chains of starch and increased availability of hydroxyl groups for the formation of new bonds with water molecules. In addition, the micropores occurring naturally on the potato starch surface ,42, presSome literature works report various effects of annealing on the swelling power of starches of various botanical origin. Pinto et al.  proved tThe resistance of the acetylated potato starch analyzed in the present study reached 11% . This reA Haake oscillating-rotary viscosimeter was used to measure the viscosity of pastes made of modified starch preparations . Flow cuViscosity measurements demonstrated that the analyzed pastes were characterized by shear-thinned non-Newtonian flow, being typical of starch pastes. Viscosity at the initial shearing phase and yield point of single-modified annealed starch preparations depended on heating temperature. In the study by Wang et al. , the annAnother step of modification, i.e., esterification of annealed preparations, contributed to a decrease in the values of coefficients characterizing paste viscosity at the initial shearing phase , which is due to the diminished structural stability triggered by the introduction of acetyl groups to the starch chain ,54. The The annealing of starch before acetylation triggered changes in the properties of the modified preparations. It contributed to a higher degree of starch substitution with acetic acid residues and to the increased swelling power of starch. Both these properties were also affected by the annealing temperature. The highest resistance to amylolysis was found for the starch preparation annealed at 53.5 °C and acetylated. The double modification involving annealing and acetylation processes increased the onset and end pasting temperatures compared to the acetylation alone. Similar observations were made for the consistency coefficient and yield point. Preparations of this type may be suitable for the controlled release of bioactive or therapeutic substances.


This study was to investigate the impact of granule size, amylose content, and starch molecular characteristics on pasting and rheological properties of starch paste/gels in neutral (water) and sugar–acid systems. Normal rice starch (RS), waxy rice starch (WRS), normal tapioca starch (TS), and waxy tapioca starch (WTS) representing small-granule starches and intermediate-granule starches respectively, were used in the study. Impacts of granule size, AM content, and their synergistic effects resulted in different starch susceptibility to acid hydrolysis and interactions between starch and sucrose-water, yielding different paste viscosities in both systems. The high molecular weight ( DP of ~104–105 AGU [Starch, the major carbohydrate in human diets, is composed of two types of glucose polymers: amylose (AM), a linear α−1,4 linked glucan, and amylopectin (AP), a highly branched glucan with α−1,6 glycosidic bonds at branch points. The molecular size of the linear AM is typically ~10–1000 times smaller than the branched AP (DP of AM ~10w/w). Granules initially swell and AM leaches out. Subsequently, the destruction of crystalline regions in the swollen granules occurs. Thickening, stabilizing, pasting, and gelling are examples of the diversified food properties obtained from gelatinized starch. The AM content, molecular size and shape of the glucan polymers, chemical composition within the granule, and granule characteristics, are the internal factors that control those properties [The function of starch in food, besides providing an energy source, is to provide structure and texture. Starch is required to undergo gelatinization prior to contributing to any desirable texture. The gelatinization process takes place when heating starch with an excess amount of water (≥65% operties .Previous studies showed the effect of granule size on swelling power (SP) and paste viscosity. Larger granules provided higher SP and viscosity due to their high capacity to hold water ,5. SwellAP is known to be responsible for granule swelling and the semi-crystalline structure within the granule. Waxy starches usually display greater peak viscosity and higher granular disruption than normal starches, thus providing a sticky paste . In contOther food ingredients besides the internal factors of starch govern starch gelatinization and starch-based food texture. Sucrose, a common sweetener, increased the gelatinization temperatures and enthalpy of starch ,14,15. TTo provide a sour taste, acidic ingredients are sometimes added to a starch-based product, and these can also affect starch gelatinization. Addition of such ingredients can result in starch hydrolysis, altering the starchy texture and its rheological properties. Acid hydrolysis preferentially attacks the amorphous regions since these regions are more accessible due to the loose packing of starch chains compared to the crystalline regions . Chain cw/v and the sucrose concentration was 35% w/v. The pH of the system was adjusted to ~3 using citrate buffer. From an application point of view, the results of this study can provide guidance for use of suitable native starches for desirable texture in clean-label food products e.g., gravies and fruit-pie filling.Although the effects of sucrose or acid on pasting and rheological properties of starch have been extensively investigated, limited studies have been done of the concomitant effects of both ingredients on starch behavior, which occur in actual food systems such as fruit-pie filling. Pasting and gelling properties of starches are governed by granule size, AM content, and molecular characteristics of the polymers as previously mentioned. Therefore, the objectives of our study were to investigate the impact of granule size, AM content, and starch molecular characteristics on physico-chemical and rheological properties of starch paste/gels in a neutral system (distilled water) and a sugar–acid system. Normal rice starch, waxy rice starch, normal tapioca starch, and waxy tapioca starch were used in the study, representing small-granule starch and intermediate-granule starch, respectively. To imitate the fruit-pie filling system, the starch concentration was 6% Native tapioca starch (TS) and native waxy tapioca starch (WTS) were obtained from Siam Modified Starch Co., Ltd., Pathum Thani, Thailand. High amylose rice grain—Chainat (CN) and waxy rice grain—Sew Mae Jan (SMJ) were provided by the Rice Department, Thailand. The other ingredients employed were citric acid , sodium citrate , sucrose  and amylose from potato .Rice starches were isolated from two types of rice—CN and SMJ—according to the alkaline method of Lumdubwong and Seib  with a sMoisture content of starch was determined following AACC . ProximaApparent amylose content of starch was measured by the method of Chrastil .w/v sucrose and pH 3). The sugar–acid system was adapted from the fruit filling model of Agudelo, et al. [Native starches were studied in two systems: a neutral system (distilled water), and a sugar–acid system  with refractive index (RI) detector . The method was according to Nguyen Vu and Lumdubwong . Six pulmax) of starch was determined by the modified method of Chrastil [2-KI solution (I2 0.127 g and KI 0.3 mg/ 100 mL) (200 µL). The sample was analyzed by spectrophotometer  with a wavelength ranging between 400–900 nm.The maximum absorbance (λChrastil : 30 mg s50). The starch granules’ morphology was examined under a light microscope  with Micro Publisher-3.3-RTV digital camera.The granule size distribution of native starch was determined using a laser particle size analyzer . A small amount of native starch was suspended in distilled water. The starch solution was added to circulating water and stirred at 1000 rpm to obtain the particle size. A refractive index (RI) of starch and water of 1.53 and 1.33, respectively, were used for the measurement. The particle size was reported as the median diameter . The ratio of starch: distilled water or sugar–acid solution was 1:2.5. The heating condition was according to Hsieh, et al. .w/v) of starch in distilled water or sugar–acid solution was determined by the method of Crosbie [The swelling power (SP) . Light transmittance of 1% , et al. .w/v starch in distilled water or sugar–acid solution were determined by a rapid visco analyzer . The pasting condition of Lumdubwong and Seib [The pasting properties of 6% and Seib  was applRheological properties of starch gels were analyzed using a rheometer  with a stainless-steel parallel plate geometry (50 mm diameter), and gap size of 1.0 mm for all experiments.w/v starch slurry in distilled water or sugar–acid solution was pre-heated in a water bath to 60 °C  or 70 °C (sugar–acid system) to reduce starch sedimentation. The pre-heated starch slurry was immediately poured onto the lower plate of the Rheometer with the temperature preheated at 50 °C. After lowering the upper plate, a thin layer of silicone oil was applied on the edge of the sample, and a solvent trap was placed on the stainless-steel geometry, in order to prevent moisture evaporation. The slurry was pre-sheared at 10/s for 1 min before starting the test.The 6% All gelation measurements were performed with constant shear strain at 0.5% (which was tested to be in the linear regime) and constant frequency of 1 Hz. The slurry was held at 50 °C for 2 min, then heated up to 95 °C at a rate of 7.5 °C/min, and held at 95 °C for 2 min. Then the starch paste was cooled to 50 °C at 7.5 °C/min, and then held at 50 °C for 4 min. After that the sample was cooled to 25 °C at 7.5 °C/min, and held at 25 °C for 5 min. These starch gels were used in further analysis of small amplitude oscillatory shear (SAOS) and large amplitude oscillatory shear (LAOS) tests.γ) range of 0.01% to 100% (logarithmic ramp mode) and a constant frequency of 1 Hz to determine the extent of the LVE region of the starch gels. For the frequency sweep tests, starch gels prepared in the rheometer (as described in 2.9.1) were allowed to relax for 5 min at 25 °C before starting the test. A frequency range of 0.01 Hz to 20 Hz was used at fixed shear strain within the LVE regime.An amplitude sweep test was performed at 25 °C with a shear strain  with constant frequency of 1 Hz, at 25 °C. The responses of the starches from the LAOS tests were analyzed using Lissajous plots and by calculating the dissipation ratio as a function of applied strain amplitude ,35.2 and 3.33 mg KI) and analyzed under a light microscope  with Micro Publisher-3.3-RTV digital camera.150 mg of cooked starch paste in distilled water or sugar–acid solution from the study of pasting properties was cooled to room temperature, then stained with 100 μL of iodine solution (1 mL solution containing: 1.67 mg Iw/v starch slurry in distilled water or sugar–acid solution was heated in a water bath (95 °C) for 20 min and periodically stirred gently by hand to reduce starch sedimentation, then cooled to room temperature. The starch gels were stained with iodine as described above and analyzed under a light microscope .For low-shear preparation, a 6% All measurements were done at least in duplicate. Analysis of variance (ANOVA) and Duncan’s multiple comparison were performed using SPSS 25 software.50) of rice starch (~9 μm) and tapioca starch (~15 μm) revealed that their granule size was small (2–10 μm) and intermediate (10–60 μm), respectively [p < 0.05). RS and WRS granules had angular and polygonal shapes and their granule size was similar (~5 μm) when analyzed by a light microscope (p < 0.05). The results were in agreement with those of Gomand, et al. [The particle size distribution of rice and tapioca starches is shown in ectively . Both stcroscope B,D. In o, et al. . The grap ≥ 0.05) independent of their amylose (AM) content. The fat content of starches was as expected since cereal starch has a higher fat content than root/tuber starch.The protein, fat, and ash contents of all starches were lower than 0.5%, implying that the starches were pure . The higmax of RS verified the presence of the linear polymers. TS contained 25% AM which was significantly lower than RS. The λmax and AM content from the iodine-binding method indicated the TS starch also contained long-chain AP. Both waxy starches, WRS and WTS, did not contain small linear molecules of AM according to their molecular distribution (p ≥ 0.05). The data suggested that the molecular size of HW AP was not directly correlated with granule size or amylose content. Nonetheless, waxy starches had a higher proportion of HW AP than normal starches. The molecular size of LW AP of TS was found to be significantly smaller than that of other starches, and WRS contained the highest proportion of LW AP. Different ratios of HW AP to LW AP indicated different heterogeneity of AP polymers which, in turn, affected the short-range and long-range orders of AP arrangement in starch granules. Seemingly, the shape of waxy AP of WTS and WRS was different. The branch points of WTS tended to be closer to the reducing ends compared to those of WRS, based on its higher λmax value (539.8 nm vs. 524.0 nm) as shown in The RS used in the study was classified as high amylose (HAM) rice, based on its AM content (Table. 1). The overestimation of its AM content determined by the colorimetric method was likely due to an interference of long-chain amylopectin (AP) . The higribution . The molribution . The fir5 g/mol vs. 7.62 5 g/mol). When converted to the weight-average degree of polymerization  than its waxy counterpart (WRS) and those of intermediate-granule starches (TS and WTS) (WTS 19.5 vs. TS 19.3) [max (The granule size and AM content evidently influenced the gelatinization properties and swelling power (SP) of starches . The geland WTS) . It is kTS 19.3) . WTS alsTS 19.3) . The exc.3) [max , resulte.3) [max . WRS als.3) [max .p of all starches in the 35% sucrose-acid system increased ~11–12 °C from that of the neutral system, and was about the same as that of wheat starch in a 30% sucrose solution [p of starches in the sugar–acid system was expected to be mainly caused by sucrose. This observation was attributed to two possible reasons. The hydrogen bond interaction between starch and sucrose reduces starch chain flexibility and granule swelling, thus delaying water accessibility into starch granules [o) and the ∆H of the second endotherm of RS increased by 12.7 °C and 0.3 J/g, compared to the neutral system. In contrast, its range of Tco was narrowed by ~9 °C (p < 0.05). The reason for this observation is most likely that sucrose predominantly interacted with rice AM, yielding granule swelling restrictions, which impeded accessibility to acid hydrolysis.The presence of sugar and acid apparently impacted starch gelatinization properties . The Tp solution . Increasgranules . Furthergranules . Our stugranules . Sucrosep ≥ 0.05). The observation suggested that water absorbability of tapioca AP was likely increased by presence of acid resulting in an increase of SP, as described by Ohishi, Kasai, Shimada and Hatae [Previously reported effects of granule size on swelling power were contradictory. Cornejo-Ramírez, Martínez-Cruz, Del Toro-Sánchez, Wong-Corral, Borboa-Flores and Cinco-Moroyoqui  showed tnd Hatae . This pop < 0.05). The high AM content of RS granules preserved the integrity of granule remnants; therefore, less light could pass through the paste. WRS also displayed a rather low paste clarity which is similar to the finding of Hsieh, Liu, Whaley and Shi [Paste clarity of starches in distilled water  was in a and Shi . The rea and Shi . The aut and Shi . The 200o, Tp, and Tc) (mono solution). They explained that the granule rigidity during heating and mixing increased due to sucrose. The sugar not only competed with starch for water, but increased H-bonding within the granule. The relative increase in PV in the sugar (1.0 M sucrose)–acid (0.1 M citric acid) system in our study was found to be similar to the relative increase of PV in the 1.0 M sucrose solution by Woodbury, Grush, Allan and Mauer [Pasting profiles of normal and waxy starches in water and sugar–acid solution are shown in  and Tc) . The pea and Tc) . The incnd Mauer . Seemingmono sucrose solution [The breakdown (BD) viscosity is the difference between PV and trough viscosity (T) or hot paste viscosity (HV). The parameter is associated with the disruption of gelatinized swollen granules. The low BD represents the resistance to shear or granule rigidity before disruption. The trough viscosity is affected by solid content e.g., granule remnants and other ingredients , amount and molecular characteristics of solubles. These factors provide the volume fraction and granule rigidity which govern the T. Our results showed intermediate-granule starch had a higher T than small-granule starch. Kowittaya and Lumdubwong  observedsolution . The relsolution . Based ow and high volume fraction of large swollen granule remnants (The setback (SB), the difference between final viscosity (FV) and T, and FV in distilled water are generally regulated by recrystallization of starch polymers (mainly AM), molecular entanglement (gel formation), and the volume fraction of granule remnants. The SB indicates gelling ability and/or retrogradation ability . Thus, lof TS AM  reasonabsolution . Howeversolution . The obssolution . The extp < 0.05). The observation clearly indicates the different characteristics of these starch gels, in addition to the starch paste viscosities from the RVA measurements. This demonstrates the importance of AM that maintains the integrity of swollen granules and strengthens the system by forming polymer networks of leached AM, giving elasticity to starch gels [p < 0.05) (p ≥ 0.05) (γmax) of RS was very short, with a value of around 0.2%  region and the effect of frequency on G′ and G″ values of starch gels were determined. The extents of the LVE region of starch gels in water  or sugar–acid solution (sugar–acid system) are presented in rch gels . In cont < 0.05) A,B. In c ≥ 0.05) C,D. The und 0.2% B, wherea ~10–15% A,C,D. Fup < 0.05), whereas other starch gels displayed similar values of G′ to those in the neutral system (p ≥ 0.05) (p < 0.05) (p ≥ 0.05). However, the extent of the LVE regime of TS and WTS gels became shorter compared to the neutral system  ( ≥ 0.05) . In addi < 0.05) D, therefl system A,C wherel system B,D. The l system A,C,D. Thl system B. In addγ) of 16% and then start to gradually distort to a rhomboidal shape. RS gels exhibited markedly different characteristics compared to the other starch gels. At strains of 4.5% and 16%, the RS gel still showed a near elliptical shape, but the loops were much wider, indicating a significantly higher viscous dissipation. This was followed by a rapid transition to a wide rhomboidal shape at 58% strain (The behavior of the starch gels beyond the LVE region was determined by LAOS measurements. Lissajous (LJ) and dissipation ratio curves are shown in % strain A. In con% strain A. The reThe viscous plots of starch gels in the neutral system (shear stress-strain rate LJ plots) are presented in The elastic plots of starch gels in the sugar–acid system are shown in The viscous plots of starch gels in the sugar–acid system are shown in Clearly, the addition of sugar and acid affects the nonlinear response of the starch gels. Regarding normal starches, sucrose inhibits starch swelling and AM leaching, as evidenced by an increase of dark-blue stains within their swollen granules B. The obIn both waxy starch gels, almost no granule remnants were observed, implying that acid promotes granular disruption even in a low-shear preparation, and their gels are polymer networks of AP B. SeeminThe rheological measurements revealed different behaviors of starch gels. RS gel was the strongest and the most brittle gel in both neutral and sugar–acid systems, compared to other starch gels which are softer and quite stretchable. Further, the results of the LAOS measurements indicated that WRS produced soft and the least brittle gel among other starches in the sugar–acid system. In addition, WRS paste was not extremely turbid as its paste clarity increased to ~55% (%T) in the sugar–acid system . The difIntermediate-granule starches displayed higher SP and volume fraction, compared to small-granule starches in both neutral and sugar–acid systems. The synergistic effect between small granule size and the presence of AM drastically restricted granule swelling and AM leaching in the sugar–acid system. The observation was confirmed by the lowest PV and the microscopy images of RS paste. Gelatinized starches with intermediate granule size were susceptible to acid hydrolysis and sucrose effect, as shown by their higher BD and SB than the small-granule starches. In contrast, sucrose effect was more prominent in small-granule starch, containing AM. The high molecular weight (The rheological behavior of starch gels was investigated by SAOS and LAOS measurements. The granule size and AM content showed an interaction effect on normal starch gel behaviors in both neutral and sugar–acid systems. RS produced a stronger and more brittle gel than other starch gels in both systems due to its small granule size, high AM content, and the presence of AM–lipid complex. The impact of starch granule size, however, was not pronounced on waxy starch gel behaviors, since their gels are AP polymer networks. In turn, the waxy starch gel behaviors were governed by AP molecular characteristics, especially in the sugar–acid system. It was found that the addition of sugar and acid showed minor impacts on starch gel behaviors in the LVE region but more evidently affected the nonlinear response of starch gels, as shown in the Lissajous curves.


Plastic waste accumulation is one of the main ecological concerns in the past decades. A new generation of plastics that are easier to degrade in the environment compared to conventional plastics, such as starch-based bioplastics and oxo-biodegradable plastics, is perceived as a solution to this issue. However, the fate of these materials in the environment are unclear, and less is known about how their presence affect the microorganisms that may play a role in their biodegradation. In this study, we monitored the dynamics of bacterial community in soil upon introduction of commercial carrier bags claimed as biodegradable: cassava starch-based bioplastic and oxo-low-density polyethylene (oxo-LDPE). Each type of plastic bag was buried separately in compost soil and incubated for 30, 60, 90, and 120 days. Following incubation, soil pH and temperature as well as the weight of remaining plastics were measured. Bacterial diversity in soil attached to the surface of remaining plastics was analyzed using Illumina high-throughput sequencing of the V3-V4 region of 16SrRNA gene.After 120 days, the starch-based bioplastic weight has decreased by 74%, while the oxo-LDPE remained intact with only 3% weight reduction. The bacterial composition in soil fluctuated over time with or without the introduction of either type of plastic. While major bacterial phyla remained similar for all treatment in this study, different types of plastics led to different soil bacterial community structure. None of these bacteria were abundant continuously, but rather they emerged at specific time points. The introduction of plastics into soil increased not only the population of bacteria known for their ability to directly utilize plastic component for their growth, but also the abundance of those that may interact with direct degraders. Bacterial groups that are involved in nitrogen cycling also arose throughout burial.The introduction of starch-based bioplastic and oxo-LDPE led to contrasting shift in soil bacterial population overtime, which may determine their fate in the environment. The widespread use of petroleum-based plastics has led to global pollution issues. In 2015, global plastic waste production is estimated at 25 billion metric tons, with only 9% of them recycled, 12% incinerated, and 79% ended up in landfills or natural environment , 4. MultBiodegradable plastics are perceived as a solution to plastic waste accumulation issues. They refer to polymers that can be mineralized by microorganisms into water, carbon dioxide, methane, and biomass. Bioplastics, a subset of biodegradable plastics, are made of renewable natural polymers from plants such as cassava, corn, and potato starch  or from The physicochemical structure of the materials, the ambient circumstances, and the microbial populations engaged in biodegradation all affect how quickly biodegradable plastics degrade . AbioticTetracladium spp. and nitrogen-fixing bacteria [The impact of biodegradable plastic polymers used as agricultural plastic mulch film on soil microbiome has been assessed previously. Muroi et al. used polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) to analyze soil microbiome following poly  (PBAT) film burial at a lab-controlled temperature of 30 °C over 7 months . They shbacteria . In contThis study monitors soil bacterial composition during the burial of two types of plastics marketed as biodegradable in Indonesia: cassava starch-based bioplastics and oxo-LDPE. We do not specifically attempt to quantify biodegradation according to any specific standards, but we rather assess how the bacterial population in soil may or may not have changed upon exposure to plastic products claimed as biodegradable. By identifying bacterial groups that arise in population over time, we will obtain preliminary insight into which bacteria may be able to utilize the biodegradable plastic material for their growth. Such information is important for identifying bacterial groups that may be used in the management of biodegradable plastic waste.Two types of carrier plastic bags marketed as biodegradable, i.e. the cassava starch-based bioplastic and oxo-LDPE, were purchased from e-commerce stores in Indonesia. Each type of plastic bag was procured from a separate store. These plastics were chosen based on their availability as consumer products in the Indonesian market. They were cut into random-sized sheets, weighed to 75 g batches, UV sterilized and buried at 10 cm depth in compost soil  in separate plastic pots (30-cm diameter). The pots were incubated on an outdoor balcony covered from direct rainwater exposure for 30, 60, 90 and 120 days. One pot was assigned for each type of biodegradable plastic and incubation time. Soil with no plastic stored in the same conditions and collected from the same depth at each time point served as controls. The inner temperature and pH of soil were measured using a digital thermometer and a pH meter at each time point, respectively. At the end of each treatment, remaining plastic was weighed. For each treatment and time point, soil attached to the remaining plastic was pooled into a sterile centrifuge tube and stored at 4 °C prior to further analysis.Both plastic bags were buried on the 9th February 2021. One pot for each plastic type and incubation time was subsequently sampled on four dates: 11th March 2021 (30 days), 10th April 2021 (60 days), 10th May 2021 (90 days), and 9th June 2021 (120 days). Over this period, the average daily temperatures ranged from 24.3–29.2 °C and the relative humidity was 74–93% [Total DNA from control soil and soil surrounding the remaining plastic was extracted using the Presto™ Soil DNA Extraction Kit  according to its manufacturer’s protocol and stored at − 20 °C. Soil samples that were not directly analyzed were stored at 4 °C for maximum 14 days. Total DNAs were visualized on a 1% agarose gel and quantified using NanoDrop™ 2000 .The V3-V4 region of 16S rDNA was amplified using the primer pair 341f (5′–GTGCCAGCMGCCGCGGTAA-3′) and 806r (5′-CCGTCAATTCCTTTGAGTTT-3′) . Amplicohttp://www.arb-silva.de/) using UCHIME algorithm [Overlapping DNA fragments were merged using FLASH (V1.2.7) . Qualitylgorithm , 35. Upalgorithm . Shannonlgorithm  using Molgorithm , 39. Thelgorithm .After 30 days, the cassava starch-based bioplastic weight was reduced by 56%. The weight reduction was less drastic afterward, with a 61, 69, and 74% weight decrease by day 60, 90, and 120, respectively  reads that were clustered into 2494 ± 246 OTUs. Sequencing of starch-based bioplastic treatment group yielded 115,495 ± 6073 reads that were clustered into 2464 ± 97 OTUs. Meanwhile, sequencing of oxo-LDPE treatment group generated 114,373 ± 4491 reads that were clustered into 2538 ± 196 OTUs.Numbers following each sample code indicate the length of plastic burial in days. The value of Shannon index represents bacterial diversity, in which higher numbers indicate higher diversity. The Simpson index has a maximum value of 1, which signifies that all members of the population are present in equal abundance.The diversity and richness of bacterial OTUs were quantified and expressed as Shannon and Simpson indices, respectively . While tThe most dominant phyla in control soil and soil introduced with starch-based bioplastic were Proteobacteria, Bacteriodota, Actinobacteria, and Myxococcota Fig.  a. This The above phyla remain present in compost soil with or without plastic exposure over time, but their composition changed Fig.  a. ProteKlebsiella, which was detected in abundance on day 30, are known to produce enzymes for starch degradation, such as α-cyclodextrin glycosyltransferase, α-amylase, and pullulanase [Longispora was abundant on day 90 and 120. Longispora fulfa tested positive in the starch hydrolysis assay [Bacillus and Nitrospira were abundant on day 120. Many Bacillus species are known to hydrolyze starch through the activity of α-amylase, an enzyme that cleaves the α-1,4 glycosidic bonds in starch [. A study on functional genes among the tropical peat swamp bacterial community by Kanokratana et al. [Nitrospira, which indicates that members of this group play a role in starch degradation in the environment. The fact that none of the above bacterial groups consistently rose up in abundance across all time points indicates that starch-based bioplastic catabolism may occur through dynamic metabolic activities of various bacteria rather than relying on specific bacterial genera or species.Prevalent bacterial genera varied across all time points and some of these genera are known for their ability to degrade starch Fig.  b. Starclulanase . Longispis assay . Meanwhin starch , 51. A sa et al.  indicateZobellela and Truepera (day 30) play a role in the decomposition of high-carbohydrate organic materials. Maity et al. [Zobellela tiwanensis strain DD5 to produce polyhydroxybutyrate using the starch-rich banana peels as a substrate. Meanwhile, Truepera was reported to thrive in compost enrichment samples [In contrast, there is a lack of evidence for starch degradation for some other bacterial genera that increased in abundance following the introduction of starch-based bioplastic. Past studies showed that members of y et al.  demonstr samples , 53.On day 60, there was an increase of Saccharimonadales abundance. To our knowledge, aside from another study that showed the enrichment of this bacterial order with polylactic acid exposure in soil , there iLongispora, Bacillus and Nitrospira, all other genera that increased in abundance on day 120, including Megamonas, Steroidobacter, Veillonella, and Bryobacter, have not been associated with starch hydrolysis thus far. There is, however, an indication that they made indirect contribution to starch degradation and/or organic material decomposition in general. Megamonas is mainly found in human faeces and the human gut microbiome. In an in vitro pea starch digestion model, Cui et al. [Megamonas was found in a large number after 8 hours of digestion. Veillonella thrives in the gut of gnotobiotic rats fed with amylomaize starch by utilizing starch degradation products derived by the amylolytic bacteria Eubacterium [V. atypica was also reported to co-exist and communicate with Streptococcus godonii during the early formation of dental plaque biofilm [V. atypica increased the expression of the amylase-encoding gene amyB in S. godonii. Bryobacter aggregatus gen. Nov., sp. nov., was reported to grow on starch, glucose, and maltose medium [Bryobacter [Bryobacter can use the starch degradation products such as maltose and glucose produced by starch degrading bacteria. Overall, this suggests that even though the above bacterial genera might not be involved in starch-based bioplastic degradation directly, they might thrive in soil by utilizing starch degradation intermediates or through other interactions within the bacterial community.Aside from i et al.  reportedacterium . V. atyp biofilm . This ste medium . While tyobacter , it is pSimilar with the observation for starch-based bioplastic treatment, the dominant phyla in control soil and soil introduced with oxo-LDPE were Bacteroidota, Proteobacteria, Actinobacteria, and Myxococcota Fig. a. The reSerratia, which was abundant on day 60  was detected in microplastic-contaminated soil [Rheinheimera (day 90) was reported in abundance in microplastic-infested water [Pantoea (day 120) was found in the gut of the polyethylene-degrading Galleria mellonella and Tenebrio molitor larvae that were kept on polyethylene-rich diet [Portibacter (day 90 and 120) was identified among major bacterial colonizers of polyethylene plastic debris [Only one genus associated with the degradation of the polyethylene backbone of oxo-LDPE emerged following its introduction in soil.  60 Fig.  b, was rtic film . This shted soil . Similared water . Pantoeaich diet , 64. Porc debris . InteresStreptomyces, members of which are known as polyethylene degraders [Streptomyces abundance was increasing over time in soil indicates that the bacteria, and perhaps other bacterial groups, may require longer than 120 days to establish succession on the surface of plastic and catabolize the material.Furthermore, the abundance of egraders , 67, wasegraders , 69. TheLongispora, Bacillus, Klebsiella, and Bryobacter [Nitrospira [Steroidobacter [Truepera [, was also shown. Furthermore, Saccharimonadales, Rheinheimera, Pantoea, and Serratia, all of which were increased following oxo-LDPE burial in soil, were reported for their nitrogen fixating and plant growth promoting activities [In soil exposed to either starch-based bioplastic or oxo-LDPE, we observed the elevated relative abundance of bacterial genera involved in nitrogen cycling. Starch-based bioplastic burial led to the increase of the nitrogen fixer yobacter –73. In ttrospira  and the dobacter  and TrueTruepera , was alstivities –80. Corrtivities . This shThis study is focused on soil bacterial community profiles during the introduction of commercial cassava starch-based bioplastic and oxo-LDPE. Fungal diversity analysis was not included as the availability of database and non-bias universal primers are lacking for this group of microorganisms at the time this study was conducted. In the future, prolonged incubation up to the point where oxo-LDPE has shown more signs or deterioration will provide a more in-depth view on microbial dynamics, particularly for the oxo-LDPE, which may require longer time to degrade.Cassava starch-based bioplastic was degraded faster in soil compared to oxo-LDPE. Our results indicated that the bacterial composition in soil changed over time with or without the introduction of either type of plastic. While the major bacterial phyla remained similar for all treatment in this study, the addition of both types of plastic led to a different shift in soil bacterial community. Various genera emerged at specific time points and none of them dominated the soil bacterial community continuously. They represent bacteria that might be directly involved in breaking down the plastic polymers, as well as those that survive by interacting with the degraders. Bacterial groups involved in nitrogen cycling also arose over time. Overall, this study suggests that the fate of biodegradable plastics in the environment is determined by a complex set of microbes that continues to change over time.