Floccularia luteovirens, a rare wild edible and medicinal fungus, is endemic to the Tibetan plateau. However, attempts to artificially domesticate this species have not been successful, resulting in extremely limited utilization of this valuable resource. This paper presents the geographical distribution of F. luteovirens, along with its ecological and biological characteristics. It explores population relations, symbiotic relationships, soil microbial community relations, fruiting body occurrence conditions, nutritional metabolism, and reproductive patterns. The cultivation techniques, as well as the edible and medicinal value of this mushroom, are also reviewed. Through an overall analysis of the physiological characteristics and current research status of F. luteovirens, the paper discusses its development prospects. The aim is to provide a reference for other researchers and promote its artificial domestication, resource development, and utilization. Floccularia luteovirens (Alb. & Schwein.) Pouzar is a rare wild edible fungus found in the Qinghai–Tibet Plateau of China. It forms mycorrhizal symbiosis with Kokanica humilis and plays an important role in the alpine meadow or grassland ecosystem [F. luteovirens holds great potential as a resource for functional food or medicine. However, as a local resource, the research on F. luteovirens is still very limited. Many aspects of this species remain unknown, such as the specific mechanism of fruiting body production, artificial culture conditions for mycelium, and the form of action of pharmacologically active ingredients. The inability to achieve commercial cultivation further restricts its processing and utilization. Additionally, environmental changes and overpicking contribute to the increasing scarcity of this resource. This review aims to synthesize the existing fragmented information about F. luteovirens and comprehensively analyze its ecological and biological characteristics, as well as its food and medicinal value, so as to raise awareness among researchers about this species and encourage further study on its conservation, domestication, and utilization.Edible fungi are a diverse group of large fungi with unique physiological characteristics and a wide range of forms. They are known for their delicious taste, rich nutrition, and diverse bioactive ingredients, making them a popular choice for healthy eating . Among ecosystem ,7. This cosystem . TherefoF. luteovirens is a member of the Basidiomycota phylum, belonging to the Agaricomycetes class, the Agaricales order, and the Agaricaceae family within the Floccularia genus [F. luteovirens has been controversial and misunderstood for a long time. It was previously thought to belong to the genus Armillaria, under the Physalacriaceae family, and was therefore referred to as Armillaria luteovirens in various studies [F. luteovirens. Through phylogenetic tree analysis, they determined that F. luteovirens belongs to the Agaricaceae family and that its species differentiation occurred approximately 170 million years ago. Liu et al. [F. luteovirens strains isolated from field collection in Qinghai Province, and then, combined with comparative genomic data, further confirmed that F. luteovirens should be classified under the genus Floccularia rather than the genus Armilaria. The NJ phylogenetic tree showed that the F. luteovirens C10 strain was closer to the species of Tricholomelaceae in a phylogenetic relationship and clustered with Floccularia albolanaripes with a bootstrap value of 99% (Armillaria luteovirens with Floccularia luteovirens (NCBI: txid493452) in 2019. ia genus . This edia genus . The tax studies , and is  studies  assembleu et al.  conductee of 99% . As a reF. luteovirens is primarily found on the Qinghai–Tibet Plateau in China. Its geographical distribution range in China is approximately latitude 28°93′–37°69′ N and longitude 90°4′–102°1′ E [F. luteovirens include Lhasa, Dazi, Langkazi, Pali, Bangda, Dingri, and others. In Shiqu County, Sichuan Province, F. luteovirens mainly grows in the grasslands along the Yalong River at an altitude of 4000–4300 m. The geographical structure of F. luteovirens exhibits significant differences. A comprehensive analysis of 91 samples from 10 geographical groups in Qinghai, Tibet, and Sichuan provinces revealed that the population genotype comprises two branches. This study also found that population genetic variation primarily originates from within the population, with substantial genetic differentiation observed between populations [F. luteovirens ranged from 0.385 to 0.876, indicating a moderate level of genetic diversity [102°1′ E . This sp102°1′ E ,16. Acco102°1′ E ,18, the ulations . Moreoveiversity .F. luteovirens is a symbiotic mycorrhizal fungus that forms a partnership with the Kobresia plants. The hyphae of this fungus are distributed in the soil at a depth of 5–30 cm. During the fruiting bodiy harvest season, white mycelia can be observed on the roots of Kobresia humilis [F. luteovirens is an ectomycorrhizal fungus [F. luteovirens occurs in alpine meadows, where the dominant vegetation consists of K. humilis and alpine weeds [K. humilis. They found that F. luteovirens is one of the dominant endophytic fungi in K. humilis [F. luteovirens often forms a ribbon-like fairy ring, with a circle width of approximately 50 cm and a diameter of about 6 m [F. luteovirens falls under type II [Leucocalocybe mongolica in the Mongolian Plateau [F. luteovirens ring exhibit higher biomass, plant height, and plant density compared to those outside the ring [F. luteovirens is closely linked to the mycorrhizal system. On the one hand, plants are able to contribute to the decomposition and activation of mineral elements in the soil through a vast network of hyphae, particularly enhancing the absorption of organophosphorus and other nutrient elements. On the other hand, plants can also serve as a source of carbon for fungi in the form of sugar or fatty acids [F. luteovirens can change minerals into usable organic forms by releasing organic acids. This makes roots absorb more minerals and improves the stress resistance of symbiotic plants. [F. luteovirens can influence the accumulation of soil metabolites, regulate plant carbon/nitrogen metabolism, and enhance the growth of above-ground tissues in alpine meadow plants. Meanwhile, it may also reduce root growth to adjust the root-shoot ratio, consequently increasing nutrient accumulation in plants. In addition, the mycelium of F. luteovirens also produces volatile organic compounds (VOCs) that regulate the distribution of root auxin, thereby controlling the root development of plants. This, in turn, affects the growth, metabolism, and environmental adaptability of plants [F. luteovirens in regulating plant growth. The fairy ring effect, caused by the growth and metabolism of mycelia, has significant impacts on the plant-soil ecosystem in the habitat. It can alter the inter-specific competitive relationship of grassland communities and influence the composition and direction of plant community succession [F. luteovirens has a minimal effect on the uniformity and succession of plant communities [F. luteovirens plays a positive role in regulating plant growth and maintaining ecosystem stability in the alpine meadows of the Qinghai–Tibet Plateau. humilis . Althougl fungus ,21, therl fungus . Examplel fungus . Howeverne weeds . In Guo  humilis . The habbout 6 m . Accordi type II . This me Plateau . Additiothe ring . The forthe ring ,30,31 thty acids . F. lute plants. . Physiol plants.  that F. f plants . Andrea f plants . This ficcession . Howevermunities . In concF. luteovirens habitat is dark, with a pH range of 6.8–7.2 and a humus layer measuring 10–20 cm. Below the humus of the soil is the parent material, containing gravel and grass roots [F. luteovirens were significantly higher than outside the circle [F. luteovirens nest soil, with a relative abundance of 85.76%. The FunGuild function predicted that the soil fungi in the habitat of F. luteovirens were mainly symbiotic, followed by saprophytic [F. luteovirens. The presence of F. luteovirens in the soil has a regulatory effect on the microbial community. In the area where mycelia grow, the diversity of bacteria increases while the diversity of fungi decreases [F. luteovirens and K. humilis enhances the competitive ability of F. luteovirens and inhibits the vitality of other fungal species in a limited ecological niche. Ectomycorrhizal (ECM) fungi play a crucial role in the rhizosphere community by interacting with various microorganisms. One of the main interactions involves the competition between different ECM fungi as they strive to occupy the root space of the host in order to obtain additional carbon sources [F. luteovirens revealed interesting findings. The number of operational taxonomic units (OTUs) in the three regions was as follows: 300 in the IN region, 1107 in the ON region, and 14 in the OUT region. No other ECM fungi were detected in any of the three regions, with only a small amount of arbuscular mycorrhizal fungi being detected. These results suggest potential competition between F. luteovirens and other ECM species [F. luteovirens in the soil has indirect effects on the composition and metabolism of soil microorganisms. This, in turn, leads to changes in the distribution and composition of metabolites in the soil. It is important to note that microorganisms in the soil have an impact on the development of mycelia, mycorrhizal synthesis, and fruiting bodies in F. luteovirens [F. luteovirens fairy ring. Further research could focus on the effects of enzymes secreted by fungi, particularly those originating from F. luteovirens, on the rhizosphere soil environment of plants.The soil of the ss roots . The decss roots . In the e circle ,33. Flocrophytic . This fiecreases . The pos sources . A studyeovirens . Soil baeovirens . At presF. luteovirens are moderately sized and lemon-yellow to sulfur-colored when fresh; when dried, they become practically white , smooth, and translucent  or on the fairy rings. The growth and development process can be divided into five stages: the primary base stage, the bud stage, the growth stage, the umbrella stage, and the decay stage. The growth cycle lasts for 18 to 22 days [F. luteovirens could tolerate temperatures ranging from −17.4 °C to −3.8 °C, which is the average temperature of the coldest month. Both temperature and light intensity have an impact on the growth of F. luteovirens fruiting bodies throughout their entire growth period. The timing and amount of rainfall directly influence the timing and quantity of mushrooms. The more rainfall there is, the more abundant and robust the mushrooms are. Additionally, precipitation can promote the various growth stages of F. luteovirens [F. luteovirens appear during the summer and autumn seasons, with an average relative humidity of 41~74%, an average temperature of 6.2~15.9 °C, an average annual evaporation of 1393.8~2441.4 mm, an annual precipitation of 344~574 mm, and a humidity coefficient of 0.42~0.78. The Tibetan Plateau is one of the regions with the highest ultraviolet radiation intensity in the world. To cope with this intense UV radiation, F. luteovirens produces riboflavin, which results in the mushrooms appearing brighter in high-UV environments [The fruit bodies of  22 days . This mu 22 days . The hypeovirens . Accordironments .F. luteovirens does not rely on its own decomposition to obtain nutrients. Studies have shown that the genes related to lignin and cellulose degradation in this fungus are significantly fewer compared to white-rot fungi and brown-rot fungi [F. luteovirens is capable of utilizing both ammonium salts and nitrates [F. luteovirens: hyphal stage, primordium stage, immature fruiting body stage, and mature fruiting body stage. This study found significant differential expression of genes involved in cell cycle (ko04111), ribosome (ko03010), MAPK signaling (ko04011), and primary carbohydrate metabolism (ko00010) pathways during reproductive growth [F. luteovirens. In the fruiting body stage, F. luteovirens exhibits a complex range of nutrient types. A study utilizing transcriptome sequencing has identified a total of nine significantly different genes associated with carbohydrates. The expression of these genes leads to the breakdown of substances in the soil habitat into monosaccharides and glucose, ultimately completing energy metabolism through the glycolysis pathway and the tricarboxylic acid cycle [F. luteovirens and their symbiotic relationship with plants remain incompletely understood. Further research is necessary to elucidate the adaptation mechanism between F. luteovirens and both biological and abiotic factors. Some scholars have studied the small-scale genetic diversity and gene exchange frequency of F. luteovirens, revealing that F. luteovirens exhibits a relatively large genome. Additionally, only a limited number of new genes were identified during the three-year study, indicating that this species heavily relies on vegetative growth and can persist underground as mycelia for extended periods [F. luteovirens. Accurately identifying mating types and genotypes is crucial for artificial domestication cultivation and hybridization breeding.As a mycorrhizal fungus, ot fungi ,46,47. Tot fungi . Currentnitrates . KEGG pae growth . Howeverid cycle . At pres periods . The sex periods . HoweverF. luteovirens mycelia, the mycelia are unable to obtain enough nutrients under laboratory culture conditions, resulting in a slow growth rate of artificially cultured mycelia. F. luteovirens hyphae have a slow growth period from germination to 42 days and then only a fast growth period of about 5 days, which is one of the reasons for the slow growth of the strain. During the stagnant growth period, the hyphae change from their initial white color to a yellowish-brown color, although the mechanism behind this phenomenon is still unclear [F. luteovirens hyphae is 15 °C to 30 °C, the optimum temperature range is 20 °C to 25 °C, and the suitable pH range is 5.5 to 6.5 [F. luteovirens mycelia. Sucrose and peptone are considered more suitable carbon and nitrogen sources, with an optimal carbon-to-nitrogen ratio of 10:1. The most effective mineral nutrient for mycelial growth is MgSO4. Licorice and wolfberry extracts, triacontanol, inositol, and selenium have all been found to significantly enhance mycelial growth [F. luteovirens strain isolated in Mexico and found that the strain reached a growth rate of 0.406 mm/d in a MEA  medium with a pH of 4. Although this growth rate was higher than previous reports, it was still slower compared to the growth rate of other cultivated or wild fungi. SHI et al. [2PO4, and 1 mg/L VB1 + VB2. After 15 days, the mycelia dry weight could reach 6.5 mg/mL. Some studies have conducted statistical analyses on the number of clamp connections in F. luteovirens strains with excellent, good, and medium hyphae growth rates, and combined analysis indicates that F. luteovirens exhibits a faster hyphae growth rate and a greater average dry weight when there are fewer clamp connections [F. luteovirens hyphae and significantly increase its biomass. The optimal concentration for selenium-enriched cultures is found to be 0.80 mmol/L [F. luteovirens mycelium. We are currently conducting research in this field and have successfully achieved dense growth of F. luteovirens mycelium on the composite medium , vitamin B1, vitamin B2, vitamin C, and vitamin E, as well as P, K, Fe, Mg, Zn, and other minerals essential to the human body [F. luteovirens with Lentinula edodes (L. edodes) and Agaricus bisporus (A. bisporus)   and foun content .F. luteovirens is comparable to that in lentinus mushrooms, reaching 3.56~8.12 g/100 g [F. luteovirens primarily consist of xylose and Arabic sugar [The polysaccharide content in  g/100 g . Additio g/100 g . Analysiic sugar , and theic sugar .F. luteovirens showed that the fruiting body was rich in fatty acids, esters, alkenes, and other compounds, with the highest relative content being linoleic acid  [F. luteovirens were identified, among which the relative contents of polyunsaturated fatty acid accounted for 10.6%, monounsaturated fatty acid accounted for 31.5%, and saturated fatty acid accounted for 56.9% [F. luteovirens showed that there were 672 genes related to cell metabolism of terpenoids and polyketones, accounting for a large proportion, indicating that F. luteovirens is a potential resource species of terpenoids and polyketones [Analysis of the volatile fat-soluble components of , 48.2%) . Based oor 56.9% . Genomicyketones .F. luteovirens ranges from 0.57 to 2.53 mg/kg, which meets the standard for selenium-rich food. Additionally, various nucleosides , esters, and sterols were isolated from the fruiting body [The selenium content in the fruiting body of ing body ,71.F. luteovirens mushrooms are a traditional Tibetan herbal medicine. Historical records indicate that it has a sweet taste and provides benefits to the stomach and intestines. Regular consumption of these mushrooms could reduce blood cholesterol levels. Moreover, it is also used to alleviate symptoms such as dizziness, headache, neurasthenia, and insomnia and has been found to have preventive effects against viral infections and diseases like beriberi. It has a high content of iron and phosphorus and is also an ideal health food for benefiting qi and nourishing blood. Due to its rich nutritional value, it also has pharmacological effects on promoting children’s development and enhancing humans’ immunity [immunity ,72,73.F. luteovirens polysaccharides towards DPPH is superior to that of Lentinula edodes polysaccharides, and the scavenging ability towards ABTS is better than that of Hericium erinaceus polysaccharides. Moreover, it has a higher moisture absorption rate than Cordyceps sinensis polysaccharides and a higher moisture retention rate than Sargassum horneri polysaccharides. F. luteovirens polysaccharides after extraction and separation can effectively increase the activities of SOD, GSH-Px, and CAT in PC12 cells while decreasing the production of ROS and MDA, thus protecting PC12 cells from H2O2-induced oxidative stress [F. luteovirens can have good scavenging efficiency on DPPH free radicals [F. luteovirens. It is a natural antioxidant that offers significant cell protection and is non-toxic. Additionally, it has the ability to chelate heavy metal ions and safeguard red blood cells against free radical damage.Polysaccharides are significant components of edible fungi with both nutritional and medicinal value. Research has shown ,76,77,78e stress . The proradicals . A highlradicals , has beeF. luteovirens have been found to inhibit tumor cell proliferation while having no side effects on normal cells [F. luteovirens exhibited potent antitumor activity by inducing apoptosis of lung cancer cells through the activation of caspase-3. This isolate consisted of six amino acids, two nucleosides, two glycosides, two terpenoids, one phenylpropanoid compound, one ester, and one alkaloid [F. luteovirens, has the ability to inhibit the proliferation of tumor cell lines L1210 (leukemia), MBL2 (leukemia), and HeLa . Furthermore, this lectin exhibited greater stability compared to typical mushroom lectins and plant lectins, as it retained its activity even at a temperature of 70 °C.The exopolysaccharides of al cells . Polysacal cells ,83. Thisalkaloid . Previoualkaloid , which wF. luteovirens has certain benefits in the treatment of diabetes; it can significantly improve the oral glucose tolerance of rats with type 2 diabetes, significantly increase the level of SOD in the serum of rats, and reduce the expression of MDA and four inflammatory factors [The water extract of  factors . Additio factors .F. luteovirens also demonstrates a significant anti-inflammatory and analgesic effect on experimental migraine rats. This extract effectively reduces vasodilation and alleviates stimulation of the trigeminal nerve [F. luteovirens mushrooms in ancient medical books to treat headaches.The water extract of al nerve . These fF. luteovirens, as an edible mushroom, is known for its delicious taste and rich nutrition. It has become increasingly popular among people, with the market price for fresh mushrooms reaching as high as six or seven hundred yuan per kilogram during the harvest season. Higher-quality mushrooms can even be sold for thousands of yuan. However, in their pursuit of economic benefits, local residents have been expanding the number and area of pickings, resulting in a constant reduction in the number of fruiting bodies [F. luteovirens, it is important to promote the concept of sustainable development among local residents. In cases where it is necessary, certain protected areas can be established to safeguard the population of F. luteovirens. While the majority of resources for researching the F. luteovirens species are currently derived from Qinghai and Tibet, it is important not to disregard the potential resources available in other regions such as Sichuan and Gansu. It may be necessary to establish F. luteovirens species banks in research institutes or universities to ensure the long-term preservation of essential germplasm resources and their genetic information. This would provide a foundation for future genetic breeding and artificial domestication research.g bodies . ExcessiF. luteovirens, a rare edible mushroom resource in the Qinghai–Tibet Plateau, thrives in a distinctive growing environment and forms mycorrhizal symbiosis with K. humilis; artificial cultivation of this mushroom has not yet been achieved. The challenge of artificially domesticating edible mycorrhizal fungi lies in their separation from the symbiotic host plant. When placed under pure culture conditions, these fungi often exhibit slow or stunted growth, emphasizing the importance of the symbiotic system in addressing this issue. There have been successful cases in which Pinus armandii Franch seedlings were inoculated with spore suspensions of Tuber melanosporum Vittad for the synthesis of ectomycorrhizal seedings [Tricholoma matsutake and pine seedlings can harvest fruiting bodies in field experiments. Although the colonized T. matsutake may be replaced by the original dominant ECM fungi during the growth of pines [F. luteovirens can also try to infect the roots of K. humilis with F. luteovirens to observe the potential formation of mycorrhizal seedlings. Another approach is to simulate wild cultivation by artificially sowing the cultivation medium covered with hyphae in the growth areas of K. humilis and other forages to observe the occurrence of hyphae. In China, mycorrhizal edible fungi account for approximately 70% of the total number of edible fungi [seedings . Mycorrhof pines , it is sle fungi . BreakinF. luteovirens has high food and medicinal value. In addition to supplementing nutrition and improving diet balance, it also has the effect of enhancing immunity, making it an ideal raw material for developing health foods. Currently, F. luteovirens fruiting bodies are mostly sold in dried form, and there are few processed products available. By processing the mushrooms into various flavored foods, consumers can have a wider range of choices. Since this mushroom is a local specialty and not well-known nationwide, effective brand building and commercial publicity are necessary to enhance its economic value. F. luteovirens contains a variety of active ingredients, particularly those with antioxidant and anti-tumor properties. If the active ingredients can be isolated and purified, it is expected to lead to the development of new cancer treatment drugs. The advancement of omics technology, including genomics and metabolomics, allows for a more comprehensive and systematic study of these active components. Some researchers have explored the extraction of biosynthetic genes and gene clusters from slow-growing basidiomycetes and transferring them to faster-growing host organisms [F. luteovirens and further advancing their development and utilization. Many mushroom strains can be grown in submerged liquid to produce a variety of bioactive substances such as proteins, carbohydrates, enzymes, lipids, etc. These substances find applications in the food industry and drug production [F. luteovirens for mushroom production, a promising approach is to concentrate on the submerged culture of F. luteovirens mycelium for functional components.rganisms . This apoduction . CompareF. luteovirens is a rare edible mushroom resource growing at an altitude of 3000 m above sea level and forms a symbiotic relationship with K. humilis. It has a high nutritional value, provides a variety of essential nutrients for the human body, and can also regulate the body’s immune ability. Existing studies have demonstrated the antioxidant, anti-aging, and anti-tumor activity of F. luteovirens, as well as its potential in the treatment of diabetes and migraine. F. luteovirens cannot currently be artificially cultivated; thus, we must first safeguard this species to prevent overharvesting and harm to the biological habitat of alpine meadows or grasslands. At the same time, we still require more researchers to thoroughly examine the interaction between F. luteovirens and the grassland ecosystem, solve the puzzle of the fruiting body’s formation mechanism, and investigate the functional component in it in order to create new beneficial health products or medications.


Introduction: Diabetic foot is a consequential and dangerous complication of diabetes, contributing to decreased quality of life, escalated hospitalizations, and increased mortality rates. Using an experimental model of diabetes, this study aims to investigate the effect of Lavandula stoechas on wound healing.Methods: A total of 35 albino Wistar rats, 250-350 grams in weight, were used. The rats were divided into five groups, seven rats in each group. Of these, 21 rats were induced with 50 mg/kg streptozotocin (STZ) to mimic the diabetic condition. Additionally, 14 rats remained non-diabetic and served as the control group. The diabetic rats were further divided into three subgroups. The non-diabetic group was split into two subgroups based on the dressing materials used . Wound dimensions were assessed on Days 0, 7, 14, and 21. Biopsies were taken from the wound sites at the same time.Results: There were significant differences between groups on Days 7, 14, and 21. The percentage of healing was highest in the Lavandula Stoechas group on Days 7, 14, and 21. Microscopic examination of the biopsies supported accelerated wound healing on Days 7 and 14. Reduced mononuclear cell density and increased hair follicle and adipose tissue development were observed in the DM (diabetes mellitus)-Lavandula Stoechas group on Day 7. On Day 14, the DM-Lavandula Stoechas group increased collagen levels and hair follicles. Similarly, the non-DM-Lavandula Stoechas group showed reduced bullae, dermal edema, and intraepithelial edema on Day 7. This was followed by increased fibroblast levels on Day 14.Conclusions: In conclusion, this study provides compelling evidence for the potential of Lavandula stoechas extract in the enhancement of diabetic wound healing. The multiple interactions revealed here highlight the need for further investigation into the underlying mechanisms. A cost-effective use of Lavandula stoechas opens up promising prospects in managing diabetic foot healing. This warrants additional research and clinical translation. Diabetic foot is a common and life-threatening complication of diabetes. The lifelong risk of developing diabetic foot is 15% in diabetes patients. Diabetic foot negatively affects patients by decreasing the quality of life and increasing hospitalization and mortality. Sothornwit et al. 2018) reported that diabetic foot decreases the scores of quality of life among the complications of diabetes 018 repor. The fivIn diabetes patients, the main goal is preventing diabetic foot. However, in the case of the development of the diabetic foot, the goal is decreasing amputation and mortality. The St. Vincent Declaration set a principal target of a 50% reduction of lower limb amputations in diabetes, yet this target has not been achieved . Even thLavandula stoechas is a common aromatic plant of the Mediterranean region. Lavandula stoechas was reported as an effective approach to improving sleep quality and reducing anxiety in various groups. Lavandula stoechas antibacterial, antifungal, insecticidal, anti-leishmanial, antioxidant, and anti-inflammatory properties were reported in several studies . HoweverLavandula stoechas is an easy-to-access, cheap plant that also has antibacterial, antifungal, insecticidal, anti-leishmanial, antioxidant, and anti-inflammatory properties . For thiThis randomized controlled study was carried out under in vivo conditions. The experimental protocol was reported according to the ARRIVE  guidelines 2.0 in this section .Hypothesis1: Lavandula-stoechas extract is an effective agent in accelerating wound healing in diabetic rats.HStudy settingThe study was carried out in the Ege University Center for Research on Laboratory Animals between 6 September and 4 October 2021. There wasn’t any blinding in this study.Study SubjectsIn total, 35  Wistar Albino rats that were 8-12 weeks old and weighing 250-350 grams were used in the study. Cohen’s criteria were used in the determination of the sample size. Accordingly, within the 95% confidence interval limits (α err prob = 0.05), at 0.80 power (1-β) and in the estimated medium effect size (dz=0.65), the minimum required the number of the samples was determined as 35 (seven in each group).Randomizationwww.sealedenvelope.com).For the roughly equal distribution of the males and females in the groups , block randomization was used . Two-steDevelopment of diabetes modelThe rats in the diabetic groups were induced by intraperitoneal injection of streptozotocin (STZ) dissolved in 0.1M cold sodium citrate buffer, pH 4.5, at a dose of 50 mg/kg. A total of 500 mg STZ dissolved in 100 ml 0.1M cold sodium citrate buffer. The rats’ plasma glucose levels were measured at 24, 48, and 72 hours after induction, and rats with a plasma glucose level of 300 mg/dL were considered diabetic , 12.Wound creationAfter inducing the diabetes model, the rats were anesthetized with 75 mg/kg ketamine and 10 mg/kg xylazine injection. The dorsal of the rats were shaved and disinfected with povidone-iodine. Three excisional wounds were then created by full tissue ablation within the panniculus carnosus muscle using a biopsy punch with a 10 mm diameter. Each wound on the dorsal of the rat was at least 1 cm away from the others. After the creation of the wounds, each rat was kept in separate cages to prevent cannibalism .Extraction of Lavandula stoechasThe Lavandula stoechas were bought from the Sepe Natural company. The Lavandula stoechas plants were collected by the company from the southwest of Turkey and extraction was performed with the hydro distillation method. A total of 4 oz. Lavandula stoechas was used in our study. The dominant components of the Lavandula stoechas are camphor and fenkan.InterventionsThe daily dressings were used for rats according to their groups throughout 21 days. Blood glucose measurement, photography of the wound surface, and biopsies collection were administered for the rats in all groups on the baseline, 7th, 14th, and 21st days.DM-Lavandula Stoechas: The rats in this group were induced with STZ and were diabetic. For the rats in this group, dressing with 0.05 ml Lavandula Stoechas oil was used for 21 subsequent days.DM-Saline: The rats in this group were induced with STZ and were diabetic. Dressing with 0.05 ml 0.9% NaCl solution was used for 21 subsequent days.DM-Control: The rats in this group were induced with STZ and were diabetic. There wasn’t any dressing for the rats in this group.Non-DM-Lavandula Stoechas: The rats in this group were not induced. For the rats in this group, dressing with 0.05 ml Lavandula stoechas oil was used for 21 subsequent days.Non-DM-Control: The rats in this group were not induced. There wasn’t any dressing for the rats in this group.Data collectionThere were three types of data; descriptive, macroscopic, and microscopic. The descriptive data were plasma glucose levels and weights. Macroscopic data were the wound surface area measurement. On Days 0, 7, 14, and 21, a researcher took a photograph of the wounds with a ruler. These photographs were used in the wound surface measurement by using ImageJ software. Walker formula was used to determine the wound healing percentages . MicroscData analysisDescriptive statistics for the study are presented as numbers (n) and percentages (%). Data were analyzed using parametric tests if the normal distribution assumptions were met and using nonparametric tests if the normal distribution assumptions failed. The results of the parametric tests are given as mean values and standard deviations; the results of the nonparametric tests are given as the median, minimum, and maximum values. Kruskal-Wallis analysis was used in the independent multiple-group comparisons if the normal distribution assumptions failed; the Dunn test was conducted in the post hoc paired comparisons. For dependent multiple-group comparisons, the Friedman test was conducted and the Dunn test was used to determine the pairs that met the significance criteria. p < 0.05 was determined to be the level of significance.EthicsEthical approval from the Ege University Animal Experiment Local Ethical Committee was obtained to carry out the study . Also, approval from the Ege University Center for Research on Laboratory Animals was obtained.Seventeen (48.6%) of the rats were male and 18 (51.4%) were female. There were four females (57.1%) and three males (42.9%) in DM-Lavandula Stoechas, DM-Control, and non-DM-Control groups while four males (57.1%) and three females 42.9%) in DM-Saline and non-DM Lavandula Stoechas groups  and Day 21 (p=0.008) (Table There wasn’t a significant difference between the groups at the baseline (p=0.744). However, there were significant differences on Day 7 p=0.035), Day 14 (p=0.002), and Day 21 (p=0.048) , Non-DM-Lavandula Stoechas (57.37%), DM-Saline 48.62%), DM-Control (39.32%), and NonDM-Control (36.79%) respectively while the rank for the wound healing percentages on Day 14 was DM-Lavandula Stoechas (88.79%), Non-DM-Lavandula Stoechas (86.07%), DM-Saline (79.82%), Non-DM-Control (66.98%), and DM-Control (64.10%) respectively. On Day 21, the highest wound healing percentage was in DM-Lavandula Stoechas with 99.14% and it is followed by Non-DM-Lavandula Stoechas (98.36%), DM-Saline (93.56%), Non-DM-Control (89.62%), and DM-Control (87.18%) respectively . This surge in ROS levels casts a shadow on the healing landscape, slowing down the intricate dance of tissue renewal . Lavandu On the 21st day, a conspicuous upshot of wound healing, surpassing 90%, was discerned in the DM-Lavandula Stoechas, DM-Saline, and non-DM-Lavandula Stoechas groups. This phase marked the culmination of an intricate sequence of reparative processes, manifesting in discernible alterations reflective of the intricate interplay of cellular dynamics. The DM-Lavandula Stoechas group exhibited conspicuous reductions in erythema, mononuclear cell count, dermal edema, and intraepithelial edema, accompanied by a discernible elevation in the abundance of hair follicles. Concurrently, the non-DM-Lavandula Stoechas group demonstrated more diminished levels of erythema and mononuclear cell density. These observations imply Lavandula stoechas' potential to modulate inflammatory markers and foster regenerative markers. The pronounced attenuation in parameters indicative of inflammation within the groups - namely, erythema, mononuclear cell count, dermal edema, and intraepithelial edema - is indicative of a trajectory approaching the resolution of the inflammatory phase. These compelling alterations, reflective of a subdued inflammatory milieu, align with prior research  and suggIn light of these comprehensive findings, Lavandula stoechas emerges as a promising contender for effective wound healing in the context of diabetes. Nevertheless, the intricate mechanisms underpinning this potential warrant further elucidation. This study paves the way for larger-scope investigations that unravel Lavandula stoechas' journey within the wound bed and its systemic influence.LimitationsWhile the current study delved into Lavandula stoechas' impact on wound healing, the exact mechanism remains veiled in complexity. Moreover, the absence of a group that solely isolated the effect of the dressing introduces another element of complexity, potentially leading to alternative interpretations of the results. Additionally, oxidative stress was not assessed in this study, which could have enriched the understanding of Lavandula stoechas' effects.In conclusion, our study signifies Lavandula stoechas' potency in bolstering wound healing within the realm of diabetes. This botanical marvel exhibited its prowess in accelerating wound healing, irrespective of diabetic status. These results showed that the H1 hypothesis in this study was confirmed. We propose that larger-scale studies and mechanistic investigations are integral to comprehensively harness the potential of Lavandula Stoechas. Furthermore, isolating the dressing effect from Lavandula stoechas' impact warrants dedicated exploration. This study marks a stepping stone toward a future where Lavandula stoechas' remarkable attributes converge to transform diabetic foot wound management.The efficacy of Lavandula stoechas against other bacterial strains still needs to be tested in future studies. The efficacy of Lavandula stoechas against other bacterial strains still needs to be tested in future studies. Also, we suggest conducting human clinical experiments to investigate the effect of Lavandula stoechas on wound healing in diabetic individuals.


Objective: to evaluate recent contributions to the literature on prognostic factors of hearing preservation in small vestibular schwannoma microsurgery. Methods: review of the most recent studies. Results: factors such as tumor size, preoperative hearing status, tumor growth rate, tumor origin, surgical approach, radiological characteristics, results of preoperative neurophysiological tests, preoperative symptoms and demographic features have been investigated and some of them reported to be significant in the prediction of hearing preservation. Conclusions: tumor size and preoperative hearing status are the most impactful factors and play a key role in patient selection for hearing preservation surgery. Other features such as fundal extension, tumor origin and impaired ABR could have prognostic value on hearing preservation. Tumor growth rate, preoperative impedance, cVEMPs and age have also recently been found to be significant, but more studies are needed. The role of preoperative tinnitus, vertigo and gender is lacking and controversial, whereas the differences between available surgical approaches have been smoothed out in recent years. Vestibular schwannoma (VS) is a benign neoplasm, usually arising from the vestibular branch of the eighth cranial nerve, but different origins are possible. It represents the most common lesion of the cerebello-pontine angle (CPA) and 8% of all intracranial tumors .Its real incidence is still debated and can vary from 1 to 20 cases per million, according to different studies . Since tDespite a potentially long asymptomatic phase, one or more of the following symptoms, such as hearing loss, tinnitus, and vestibular dysfunction, are a common finding in VSs patients. Typically, the otological clinical examination is completely negative, while pure tone audiometry may show a unilateral sensorineural hearing loss (SNHL) or an interaural difference in hearing threshold. The vestibular clinical examination may be impaired, but there are no pathognomonic findings. The videonystagmography (VNG) is more sensitive in identifying vestibular nerve disfunction and may also quantify the damaged number of fibers. Neurophysiological tests  are used to determine the damage on the cochlear nerve. The facial nerve is often unaffected by small tumors, while larger tumors may present with subclinical or clinical nerve deficit; this can be assessed using the House-Backmann scale and quantified with electromyography.When a VS is suspected, high-resolution contrast-enhanced MRI is the gold standard to confirm diagnosis. T1 sequences enable identification of a mass in the CPA, iso-hypointense to the cerebral tissue, with intense gadolinium-contrast enhancement; when evaluated in T2, the tumor appears hyperintense. CSF-cisternographies sequences  are useful for visualizing cranial nerves and vascular structures at the skull base-sequences and allow accurate for evaluations of tumor relations with them; these sequences are also essential to determining VS extension to the fundus of the internal auditory canal (IAC). High resolution CT scans are useful for evaluating petrosus bone structures in a preoperative setting; they also allow comparisons with the size of the affected IAC, which can be enlarged by the tumor, with the contralateral IAC.The optimal way to calculate tumor dimension was initially discussed in the first Acoustic Neuroma Conference in 1991 (Copenhagen), but no clear agreement was reached. In 2001, forty specialists met in Tokyo in the Consensus Meeting on Systems for Reporting Results in Acoustic Neuroma ; the linIn the last decades, the increasingly widespread and early use of MRI to assess otological and neurologic symptoms has led to an increased discovery of small tumors in the initial phase of their natural history. These patients usually have no complaints, and their hearing function is often unaffected, making it necessary to implement treatment options that preserve hearing function.The most widely used scales to report hearing outcomes are Tokyo  and AAOHTo date, treatment of small tumors is still a debatable issue and is the object of the present review.The available therapeutic strategies are: observation with periodic MRI scan, microsurgery, or radiosurgery. Small tumors are traditionally proposed for observation at first, with annual repetition of the MRI scan; active treatments are reserved for growing tumors. However, it has been recently shown that early surgery in small tumors can lead to clear advantages for the patient, in terms of curing disease, hearing function and preservation of the facial nerve, with better outcomes than conservative treatments ,11. The However, the role of the factors influencing and predicting the hearing outcome in the preoperative setting is still debated. This has promoted investigation of possible prognostic factors that would help to select the best candidates for HPS in relation to the inclusion criteria, with the aim of improving the outcome through the identification of reliable prognostic predictors on the likelihood of retaining hearing  when usiThis review focuses on the most recent contributions investigating which prognostic factors can predict successful outcomes, with the aim of selecting the best candidates for HPS.For this narrative review, the most recent studies published on hearing preservation in the surgical management of vestibular schwannoma were considered. The research conducted through the Pubmed library using the proper MeSH term for VS , combined with other terms referring to hearing preservation surgery ; both RS and MCF approaches were included. Duplicate records were removed, and the remaining ones were screened for suitable records, i.e., studies investigating prognostic factors for HPS in LV patients. Papers not in English or unavailable for consultation were excluded.No mandatory time interval has been set a priori in order to obtain as comprehensive a collection of factors as possible; on the other hand, when a large amount of literature was available, only the most updated works were considered; in some cases, older studies were also selected to allow for discussion of the changing role of prognostic aspects over the years.When the literature investigating the role of a certain factor in the outcomes of HPS in small tumors was available, case series referring to the same predictor in larger VSs were excluded, since the group of small tumors represents the target of the hearing preservation procedures.The reported prognostic factors are tumor size, growth rate, preoperative hearing status, vestibular nerve of origin, surgical approach, presence or absence of the “fundal fluid cap” and other radiologic characteristics . Other preoperative neurophysiological tests , symptoms  and demographic features  were investigated, too.Articles selected for this review are shown in p-value < 0.05.The considered prognostic factors are summarized in Tumor size is the first identified and one of the best-known factors that plays a leading prognostic role and greatly influences patients’ selection.This aspect was initially investigated by Kemink and colleagues in 1990, who identified a size <1.5 cm as a criterion for predicting good postoperative hearing outcomes . The rol3 were considered to have significantly better chances for preserving hearing function, while tumor dimension assessed with linear measurement did not reach statistical significance [Gjurik et al. tried to correlate both tumor volume and linear dimension with postoperative audiological outcomes; in their study, only patients with a lesion volume <0.20 cmificance .In 2020, Zanoletti et al., retrospectively analyzed hearing outcomes in a cohort of consecutive patients (100 cases) treated with a HPS procedure. They all were diagnosed with VS and operated on between 2000 and 2012 using the microscopic retrosigmoid approach combined with retrolabyrinthine meatotomy; the multivariate analysis concluded that an extrameatal tumor size of less than 7 mm was an independent predictor of good postoperative hearing function  .Based on the reported literature and our experience ,13,21, wA recent paper by Lovato et al. has retrospectively analyzed 92 patients with a small-medium tumor who underwent an operation using the MCF approach between 1995 and 2015. A tumor growth rate >2.16 mm/year was found to be an independent negative predictor for successful HPS via MCF (OR 8.5) . FurtherPure tone audiometry and speech audiometry in VS patients are the most used tests for assessing preoperative hearing status and estimating tumor damage on the cochlear nerve. The prognostic role of preoperative hearing function in relation to the postoperative hearing preservation rate has been widely debated. Although useful to group results, the use of different classification systems  for individual sound intensities from 55 dB to 75 dB in the operated ear and speech detection threshold (SDT) were found to correlate with good hearing outcomes, but no significance was obtained for the SDS value . Di MaioOur cohort of patients were treated using a RS approach and retrolabyrinthine meatotomy, and the results were recently published; the median tumor size was 10 mm in the CPA. Statistical analysis showed that the optimal preoperative hearing threshold cutoffs for hearing preservation purposes are 21 dB PTA  and 90% SDS  and confirmed that better preoperative hearing status allowed for lower rates of post-surgical hearing loss. This can be explained by the greater reserve of functional fibers present in patients with good hearing, which would therefore better support the surgical damage . To dateSchwannomas of the pontocerebellar angle usually arise from the vestibular branch of the 8th cranial nerve, but other origins are reported, i.e., the cochlear nerve or facial nerve ; at the Retrosigmoid (RS) and middle cranial fossa (MCF) are the most used surgical approaches for hearing preservation in VS surgery. The difference between hearing outcomes provided by these techniques has been investigated since the end of the twentieth century; early research seems to show a higher prevalence of hearing preservation in MCF compared to RS , respectMost recent literature seems to provide an inversion in hearing outcomes, with comparable or better ratio of preservation provided by the RS approach (OR 0.744) ,34, althVSs are preoperatively evaluated with gadolinium enhanced MRI. High resolution T2 sequences  allows assessment of the presence of the “fundal fluid cap”, i.e., the hyperintense signal corresponding to the presence of cerebrospinal fluid (CSF) at the fundus of the internal auditory channel (IAC). This is typical in VSs not involving the lateral part of the canal. The correlation between this aspect and HP was investigated in literature and results were initially ambiguous. In 2003, Kokaoglu retrospectively studied 22 patients, operated on using either the RS or MCF approach, and confirmed that a tumor involving the fundus or a short distance between the tumor and the fundus are risk factors for unsuccessful HPS . The posIn 2019 a study by Tu et al. evaluated the preoperative and postoperative cochlear signal on FLAIR sequences in VSs cases which had undergone HPS with RS or MCF approaches. Preoperative signal does not change between preserved and unpreserved HPS, but postoperative values are lower in successful cases .Preoperative assessment of VS patients should also involve neurophysiological tests to better evaluate tumor damage on the nerve. Auditory brainstem response (ABR) is the most used, due to its easy execution and low costs. Many papers have studied the relation between this test and hearing outcomes without finding any correlation ,42,43; nPreoperative impedance was also evaluated and successfully correlated with postoperative hearing outcomes: intensity level needed for simulating the stapedial reflex and abnormal reflex are recently reported as prognostic factors .In 2018, Hochet suggested that cVEMPs may be useful for predicting HP outcomes; they calculated the preoperative amplitude asymmetry ratio in their VS patients: it was significatively lower in the group with successful HP compared with the other one. They calculate that an amplitude asymmetry less than 24% has a positive predictive value for assessing postoperative hearing preservation of 91.6% .Vestibular schwannoma patients may be asymptomatic or suffer mainly from sensorineural hearing loss, tinnitus and/or vertigo; while the role of the former as an unfavorable predictor of HP has been widely described ,22,23,24Preoperative tinnitus has recently been proposed as an indicator of poor hearing reserve and appears to predict low HP rate , but morAge and gender are demographic features whose role was investigated as prognostic factors for HP. The first one has been reported in the past without reaching statistical significance ,43, but Gender has occasionally been evaluated, e.g., by Nadol et colleagues, without finding any difference between male and female patients . UltimatIn addition to the varyingly impactful roles of the factors examined in this review, other aspects may influence the audiological outcomes in hearing preservation surgery in VSs and need to be mentioned. As in every surgical procedure, the surgeon’s experience has a certain impact in the outcome; in particular, hearing preservation in VSs needs a very delicate dissection of the cochlear nerve so as to not damage the fibers and or reduce its blood supply. Such complicated procedures should be performed in a tertiary referral center by well-trained surgeons.Moreover, different techniques have been proposed to monitor the nerve during surgery, i.e., Auditory Brainstem Responses (ABR), Direct Eighth Cranial Nerve Monitoring, Cochlear Compound Nerve Action Potentials (CNAP), Transtympanic Electrocochleography, Distortion Product Otoacoustic Emissions, Postauricular Muscle Responses. All of them may play a role in hearing preservation, but literature is lacking standardized studies, necessary for evaluating their true efficacy, determine the best one for each situation and understand their predictive role for HPS, as a recent review concluded . To dateThe most important factors showing a predictive role in hearing preservation are tumor size and preoperative hearing status; these features play a prominent role in the selection of patients undergoing HPS. Other reported relevant features which might influence the postoperative outcome, although without strong statistical evidence, are fundal extension, tumor origin and, as evidenced in our experience too, impaired ABR. Recently, tumor growth rate, age, preoperative impedance and cVEMPs have also been debated. Studies evaluating the prognostic role of preoperative symptoms (except hearing loss) and gender are lacking. The differences between surgical approaches  have smoothed out in recent years and are more greatly influenced by the experience of the surgeon than by objective factors; the combination of the retrolabyrinthine meatotomy with the RS approach to fully expose the whole IAC, on the other hand, has provided safer handling of the tumor-nerve interface at the distal end of the meatus. The role of intraoperative cochlear nerve monitoring techniques has yet to be properly investigated.


The steel industry is one of the noisiest industries, which can predispose workers to hearing loss. In Egypt, the demand for steel is increasing due to the construction of new infrastructures as bridges, flyover roads, buildings, and towers; however, little is known about the prevalence of occupational noise-induced hearing loss (NIHL) among steel workers. Understanding the distribution of the affected workers is crucial for planning prevention strategies. This study aimed to estimate the prevalence of occupational NIHL among Egyptian steel workers and identify its correlates.n = 606) were enrolled and divided into two groups: noise-exposed workers (n = 396) and unexposed workers (n = 210). Univariate and multivariate regression analyses were performed.This study was conducted at two steel factories in Egypt in November 2021. It involved an initial retrospective review of the factory medical records of the latest periodic medical examination conducted on workers from July to September in the year 2021 representing workers’ health status in that year. Then, a case–control approach analysis was carried out. Eligible workers (p < 0.001). In noise-exposed workers, age and tinnitus were independent predictors of hearing thresholds, while tinnitus was found to be an independent predictor of NIHL after adjusting for age and job duration .Occupational exposure to hazardous A-weighted equivalent noise level (> 85 dB) was associated with higher hearing thresholds at all frequencies (highest at 4 kHz followed by 6 kHz), particularly in younger workers below the age of 40 years. Nearly 71% of noise-exposed workers had hearing impairment, and 47% had NIHL compared with unexposed workers . The probability of NIHL in noise-exposed workers was 6.55 times higher than that in unexposed workers (OR = 6.55, 95%CI = 4.13, 10.40; Almost half of noise-exposed workers had NIHL. Tinnitus was found to be an independent predictor of NIHL. Decreasing noise exposure levels in steel plants is recommended to reduce hearing loss. Future research is required to study the effect of tinnitus on audiometry measurements among workers with NIHL.The online version contains supplementary material available at 10.1186/s42506-023-00135-7. Globally, the demand for steel is increasing due to the construction of new infrastructures such as bridges, flyover exchange roads, buildings, towers, and railways. This sector has provided employment for millions of people . In the Excessive noise exposure at work can result in a sensory neural injury to the inner ear that leads to a partial or complete bilateral hearing loss. Occupational noise-induced hearing loss (NIHL) develops slowly over several years of exposure at work to continuous or intermittent noise exceeding the recommended exposure limit (action level) of 85 dB(A) during an 8-h shift, or impact noise exceeding 120 dB(A) during an 8-h working shift –7. It afAccording to a review by Chen et al. (2020) which included 105 studies, the burden associated with occupational noise varies widely across countries and occupations globally, ranging from 11.2 to 58% and is one of the most reported occupational diseases, particularly in the less developed regions in the world , 13.In less developed countries, such as Egypt, little is known about the prevalence of occupational NIHL in the steel industry . Since oA retrospective design was adopted for this study. Medical records of the latest periodic medical examination of workers at two steel factories in Egypt were reviewed in November 2021. The medical examination was conducted from July to September of the same year and represents the health status of the workers in that year.n = 88), previous ear infections (n = 5), history of exposure to noise during military service (n = 3), family history of hearing impairment (n = 2), and conductive hearing loss (air–bone gap > 10 dB) (n = 1). Additionally, women workers (n = 4) were excluded.The medical records of the selected factories included data of 709 workers, all of whom were men except for four workers. The inclusion criteria set for enrollment in the current study were male workers who had a job duration equal to or more than 5 years. Women workers and those with any condition considered as confounders to NIHL were excluded. Accordingly, 103 workers were excluded because of job duration less than 5 years (The 606 eligible workers were divided into two groups based on noise exposure: (i) workers exposed to hazardous occupational noise, necessitating actions (action level), where the workplace area A-weighted equivalent noise level was equal to or more than 85 dB and (ii) unexposed workers employed at non-manufacturing departments at the same factories who were not exposed to hazardous occupational noise. Exposed workers were further categorized according to audiometry results into workers with NIHL or free from NIHL.α = 0.05).A power analysis was conducted . It showed that enrolling 396 noise-exposed workers and 210 unexposed workers is capable of detecting the least difference in prevalence of NIHL of 17% between both groups , with a A transfer sheet was designed to retrieve relevant data from the records. The sheet included the following:Workers’ medical records were reviewed for sociodemographic data ; occupational data ; and medical condition .In the periodic medical examination at the selected factories, a pure-tone audiometer was used to assess hearing acuity  for bothIn this study, according to the World Health Organization (WHO) noise exposure guidelines, hearing impairment was defined as a hearing threshold > 25 dB at any examined frequency  , 5. The The percentage of hearing disability was calculated for each worker according to the Egyptian occupational health standards (OHS) formula  as folloFactory records were reviewed to obtain measurements of workplace area A-weighted equivalent noise level. At both factories, measurement was done using a sound pressure level noise meter (3 M™ Sound Detector SD-200), manufactured according to the International Standard Classifications . The A-weighted network was selected, and the sound pressure level meter was calibrated before use. Multiple readings were recorded during the shift, then the average noise level was calculated (in dB) for each workplace area. At workplace areas with an A-weighted equivalent noise level ≥ 85 dB , workers were considered as noise-exposed workers. Whereas at workplace areas with an A-weighted equivalent noise level < 85 dB , workers were considered unexposed.The SPSS v.22  was used for data analysis. Descriptive statistics were used to present qualitative data (frequencies and percentages) and quantitative data (mean and standard deviation). Data analysis involved an initial comparison between noise-exposed workers and unexposed workers to identify the frequency of occupational NIHL. Then, among noise-exposed workers, a case–control approach analysis was carried out to determine factors associated with NIHL.n = 606), hearing thresholds (dB) at specified tested audiometry frequencies (Hz), and ISO values were presented using mean and standard deviation for both noise-exposed and unexposed workers, stratified by age into four groups . The prevalence of hearing impairment and NIHL were calculated. A case–control approach analysis using univariate logistic regression was conducted to compute odds ratio (OR) and associated 95%CI to quantify the probability of hearing impairment or NIHL (dependent variable) associated with noise exposure (independent variable).Among all workers in the study (n = 396), the mean hearing thresholds was calculated among the four age groups and three job duration groups . Multiple linear regression analysis was used to determine predictors of hearing threshold at the tested frequencies. In addition, univariate logistic regression was conducted to compute the odds of NIHL (dependent variable) associated with each sociodemographic, occupational, and medical factor (independent variables). Subsequently, multivariate logistic regression was conducted to model NIHL as a function of the significant factors identified in the univariate analysis, namely age, job duration, and tinnitus, to study their independent effect. The adequacy of the model in data fitting was determined using Nagelkerke’s R2 and Hosmer and Lemeshow goodness-of-fit test. All statistical analyses were judged at a level of significance of 5% (α = 0.05).Among noise-exposed workers (As for workers with hearing disability (> 0%), a comparison was made between the mean percentage of hearing disability calculated using the Egyptian formula and AAO-ACO formula.Among the enrolled workers, 64.7% were below the age of 40, 75% lived in urban areas, 60% had attained a high school education, 87% were married, and 34% had never smoked. Seventy-seven percent of workers were blue-collar workers, 71.9% had a job duration of less than 10 years, and 67.7% worked in shifts. Thirty-nine percent of the studied workers worked at the production department, and 40% were production technicians and supervisors (Table n = 396) and unexposed workers (n = 210) with respect to age, job duration, smoking status, ear-related medical conditions, or tinnitus , followed by 6 kHz (28.67 ± 11.5) (Table p < 0.001). In addition, the probability of binaural NIHL in noise-exposed workers was 6.55 times higher than that in unexposed workers  . Univariate analysis revealed a significant association between noise exposure at work and binaural hearing impairment and NIHL. The probability of binaural hearing impairment in noise-exposed workers was 2.93 times higher than that in unexposed workers   Table . In mult5) Table .Table 5Un = 77), the mean percentage of hearing disability using the Egyptian formula was similar to that calculated using the AAO-ACO formula . However, when workers were stratified by age, the mean percentage of hearing disability calculated using the AAO-ACO formula was higher than that calculated using the Egyptian OHS formula particularly among workers older than 40 years old  was 77 (19.4%) according to the Egyptian formula and 98 24.7%) according to the AAO-ACO formula. Among them  and NIHL (47%) were reported, and tinnitus was found to be an independent predictor of NIHL. The study recommends decreasing noise exposure levels in steel plants to reduce hearing loss. In addition, future research is needed to evaluate the effect of tinnitus on auditory measurements in workers with NIHL.Additional file 1: Figure S1: Mean of the mean hearing threshold at low and high audiometry frequencies, and ISO value among noise-exposed and unexposed workers stratified by age group, at two steel factories in Egypt, 2021 Abbreviations: HT: hearing threshold; dB: Decibel; Hz: Hertz. Low frequencies: average of values of HT at 0.5, 1, and 2 kHz; High frequencies: average of values of HT at 3, 4, and 6 kHz; ISO value: average of values of HT at 0.5, 1, 2, and 4kHz. aMann-Whitney U test; bStudent’s t test; ; *P <0.05; **P<0.01; ***P <0.001. A: right ear; B: left ear. Figure S2. Mean of the measured hearing thresholds at specified audiometry frequencies among noise exposed workers stratified by age, at two steel factories in Egypt, 2021 Low frequencies: average of hearing thresholds at 0.5, 1, and 2 kHz High frequencies: average of hearing thresholds at 3, 4, and 6 kHz ISO value: average of hearing thresholds at 0.5, 1, 2, and 4 kHz Abbreviations: HT: hearing threshold; dB: Decibel; Hz: Hertz A. right ear; B. left ear. Figure S3. Mean of the measured hearing thresholds at specified audiometry frequencies among noise-exposed workers stratified by job duration, at two steel factories in Egypt, 2021. Low frequencies: average of hearing thresholds at 0.5, 1, and 2 kHz; High frequencies: average of hearing thresholds at 3, 4, and 6 kHz; ISO value: average of hearing thresholds at 0.5, 1, 2, and 4 kHz. Abbreviations: HT: hearing threshold; dB: Decibel; Hz: Hertz A. right ear; B. left ear. Table S1. Multiple linear regression of predictors of hearing threshold at tested frequencies among noise-exposed workers at two steel factories in Egypt, 2021.


Recent years have observed a significant surge in research and industrial focus on the biosynthesis of valuable chemicals and natural products. This trend has been primarily driven by the increasing demand for green manufacturing of pharmaceuticals, food ingredients, agricultural products, bioplastics, and important chemicals. Microorganisms play a central role in biosynthesis, and the effectiveness of biocatalysts determines the overall success and acceptance of biosynthesis technologies. With substantial research efforts in strain and bioprocess engineering, there have been significant developments in biosynthesis. Nevertheless, many of the developed technologies for biosynthesis have not been explored commercially due to their low competitiveness and inadequate production performance metrics. The primary challenges include the low stability and tolerance of microorganisms to stressors, slow growth rate, unbalanced metabolic pathways, and inefficient distribution of carbon flux, leading to unwanted byproducts.Overcoming these challenges requires multidisciplinary and multidimensional efforts, and hence, there has been a growing interest in the exploration of novel strains and metabolic engineering strategies to develop efficient cell factories. These approaches particularly aimed to modulate pathways and engineer strains to enhance the performance of biocatalysts beyond what is observed in their wild counterparts. Furthermore, considerable attention has been devoted to the midstream step, which involves fermentation and requires careful configuration and simulation to achieve the desired levels of titer, yield, and productivity for the target product.The objective of this Research Topic (RT) was to provide valuable insights into recent advancements in engineering strategies for the development of cell factories and bioprocesses, leading to the establishment of sustainable biosynthesis technologies. With a compilation of 10 articles, this RT offers an up-to-date overview of various aspects, including microbial hosts as cell factories, metabolic pathways, product streams, bioprocessing strategies, and optimization techniques used in biosynthesis. The published articles were authored by researchers affiliated with esteemed institutions across the globe, including countries like the United States, China, Denmark, Sweden, South Korea, Colombia, and Spain. The editorial team expresses sincere gratitude to all the authors for their valuable contributions to this RT.3O4 nanoparticles on a metal–organic framework . However, microbial systems are generally more convenient and cost-effective compared to biocatalysts. Microorganisms play a central role in biosynthesis, where a wide range of hosts have been explored. The selection of a suitable host depends on factors such as feasibility, genomic knowledge, available engineering tools, and the intended use of the target product. For instance, the model host E. coli is frequently used in target product biosynthesis due to its extensive genetic information and engineering capabilities, as demonstrated in Carranza-Saavedra et al. Nevertheless, if the synthesized product is intended for use in food preparations, the use of E. coli as a cell factory may raise safety concerns. In such cases, attention may shift to generally recognized as safe (GRAS) strains, as reported in a study by using Bacillus subtilis for 3-hydroxypropionic acid (3-HP) biosynthesis .Biosynthesis of value-added chemicals primarily involves biocatalysts, which are generally categorized into enzymatic and microbial biocatalysts. In a study, a novel enzymatic biocatalyst was developed for D-phenyllactic acid biosynthesis by immobilizing lactate dehydrogenase with FeB. subtilis cell factory containing the 3-HP producing pathway was used to biosynthesize 3-HP from glycerol , while a general pathway like the glyoxylate cycle (GOC) is capable of producing various value-added compounds. This RT published a review on GOC that comprehensively discussed the metabolic regulation of GOC and advancements in biosynthesis performed with this pathway .The development of a cell factory for the target host requires the construction of a pathway, which can be native or heterologous, and may consist of either product-specific or general pathways. For example, a Otten et al.). Using clostridial cell factories, the authors reported up to 200 mM titer and 8.1 mM/h productivity of caproate. Likewise, biosynthesis of several other platform chemicals was also reported in this RT, including 3-HP  and 2-ketoisovalerate . Apart from platform chemicals, the production of enzymes has also gained attention. For example, alkaline protease, which has widespread industrial applications, was successfully produced by microorganisms heterologously expressing a relevant gene from B. subtilis into B. amyloliquefaciens . Similarly, laccase production has been reported using Trametes versicolor and a novel inducer called copper-glycyl-L-histidyl-L-lysine (GHK-Cu) . Another group of products is dedicated to food or health-related applications, and this RT has reported biosynthesis of several such products, including adenine , D-phenyllactic acid , and monoclonal antibodies .To date, a wide range of value-added and platform chemicals have been reported to be produced by microbial biosynthesis from inexpensive and non-fossil fuel-based substrates with competitive titer and productivity. For example, caproate (hexanoate), which is a valuable platform chemical with its applications in various fields, was biosynthesized from sugars . This system exhibited notably higher titers and productivity than monoculture systems. Once a cell factory is developed, the next step is bioprocessing of appropriate substrates, typically involving fermentation. However, this technology presents certain challenges, such as the non-targeted flow of carbon flux. Additionally, achieving optimal efficiency during fermentation can be difficult due to varying conditions between cell growth and product synthesis. In this context, resting cell or whole cell technology has gained attention in recent years. This technology was applied in a study on salidroside biosynthesis, which is a plant-derived bioactive compound . The authors optimized the conditions and reported excellent conversion efficiency and regioselectivity using the whole cells of Aspergillus oryzae. In another attempt, chemical and enzymatic synthesis methods were replaced for adenine by exploring fermentation and enzymatic approaches. A fermentation system coupled with a ceramic membrane was employed to enhance permeability . This technology led to significant improvements in cell viability and product recovery, with an average adenine titer of 14 g/L.Recent advancements in microbial biosynthesis have utilized advanced technologies to obtain efficient microbial systems and bioprocesses. Coculture technology is one of them that has received significant attention recently. In one study, a novel coculture system was designed for caproate biosynthesis using clostridial species, specifically Over the past two decades, there has been a significant research focus on the biosynthesis of valuable compounds with microorganisms playing a crucial role. The aim has been to develop efficient cell factories and bioprocess technologies for sustainable biosynthesis. This RT presents a compilation of 10 high-quality articles, showcasing various research efforts. These articles cover essential aspects such as cell factories, host streams, product ranges, and emerging technological strategies. However, to fully unlock the potential of these biosynthesis technologies, it is imperative to address the challenges associated with microorganisms and bioprocessing through further innovative research. By doing so, we can pave the way for the widespread adoption of biosynthesis and drive the development of sustainable and efficient production methods across a wide range of applications.


Beauveria includes important entomopathogenic and endophytic fungi; among them, Beauveria bassiana is the most studied species. However, there is little knowledge regarding their antimicrobial activity. The current research has been conducted to evaluate the in vitro antagonistic activity of B. bassiana and the antimicrobial efficacy of its Exo and Endo metabolites against Bacillus cereus, B. megaterium, Clavibacter michiganensis , Xanthomonas campestris, Pseudomonas aeruginosa and P. fluorescence . In addition, solid-phase microextraction (SPME) was coupled with Gas Chromatography-Mass Spectrometry (GC/MS) to qualitatively measure the volatile organic compounds’ (VOCs) metabolic profile of the most efficient studied isolate of B. bassiana. The obtained results showed that the isolate UniB2439-3 has a promising antibacterial effect against most of the studied target bacteria. An SPME-GC/MS analysis of VOCs revealed the presence of ethanol, butanal,2-methyl, 2,4-dimethyl-1-heptene, octane, 4-methyl and β-elemene as the dominant bioactive compounds. The results demonstrated that the efficient isolate of B. bassiana can be potentially used as a biocontrol agent against several bacteria, especially G+ve ones.The genus  Beauveria includes entomopathogenic and endophytic fungi, which are widespread in different habitats [Beauveria can produce enzymes for biotransformation and biodestructors [B. bassiana and B. brongniartii, are able to produce mycoinsecticides [B. bassiana is also a beneficial microorganism (BM) and endophytic fungus (EF) in several crops and is commonly known as biological control agent against a variety of agricultural pests [B. bassiana has many advantages, such as being a form of eco-friendly management compared to chemical pesticides, and being harmless to human health [B. bassiana in reducing a range of nuisance insects, where it can induce direct insect mortality [Genus habitats ,2,3. Furtructors ,5,6. Somcticides . B. bassal pests ,9,10. Thn health ,10,11,12ortality ,14 and rortality .B. bassiana and their antifungal effect against Botrytis cinerea in tomato and chili pepper, concluded that all studied strains had significant in vitro antagonism against B. cinerea. The same study reported that the native strains of B. bassiana were able to colonize tomato and chili pepper tissues and provided important levels of antagonism against B. cinerea [A recent study, conducted by Barra-Bucarei et al.  to evalu cinerea .B. bassiana have plant-growth-promoting effects (PGP) and are a protective agent for tomato plants against B. cinerea, Alternaria alternata, the pest aphis, and Macrosiphum euphorbiae [Sinno et al.  reportedphorbiae .B. bassiana against some aerobic pathogenic bacteria was tested by Parine et al. [B. bassiana possesses a strong inhibitory activity against many of the tested species, especially Bacillus megaterium, B. subtilis, B. sphaericus and Escherichia coli [Micrococcus luteus, Pseudomonas aeruginosa and a low effect against Streptococcus pyogenes and Chromobacterium violaceum [B. bassiana protected tomato and potato seedlings from the damping-off disease caused by the soil-borne pathogen Rhizoctonia solani [The results showed that some studied isolates were able to control the two phytopathogens, and one isolate was also able to promote plant growth . The ante et al. . The reshia coli . It showiolaceum . In anota solani ,19. Recently, there is a large amount of interest in discovering natural-substances-based plants or those with microbe origins that have an antimicrobial effect ,21. HoweB. bassiana or their mechanism(s) of action regarding either their antimicrobial or plant-growth-promotion effects. A recent study conducted by Wang et al. [B. bassiana produces a variety of toxins, such as beauvericin, bassianin, bassianolide, beauverolides, tenellin, oosporein, and oxalic acid, which enable B. bassiana to invade, parasitize, and destroy host tissues. Therefore, the precise chemical characterization and determination of the main bioactive single substances of B. bassiana will certainly aid in understanding its biological importance. In addition, the details of the chemical constituents of B. bassiana will undoubtedly have various applications, such as controlling plant diseases, taking into consideration the heavy reliance on chemicals that are extremely harmful to the environment as well as plants, animals, and human health. Furthermore, the insecticidal effects of B. bassiana have also been extensively studied, while their antifungal or antibacterial effects have received less attention.There is little information regarding the bioactive metabolites with antimicrobial activity produced by either diffusable or volatile g et al.  reportedDifferent volatiles are produced in huge quantities by a number of microorganisms. The volatile molecules, which can be both organic (VOCs) and inorganic, are crucial for such an environment, since they have the power to affect both beneficial and harmful microbes . The sigB. bassiana. Hence, the chemical composition of B. bassiana metabolites will aid in the detection and differentiation of this species from others. The full identification of its metabolite profile can aid in its utilization in industrial, agricultural, and pharmaceutical fields. In addition, in this research, we will expand the possible benefits of B. bassiana against new non-reported target phytopathogens. The aims of the current research were to: (i) evaluate the antagonistic activity of five isolates of B. bassiana against some bacteria; (ii) investigate the in vitro antimicrobial activity of diffusible and volatile metabolites produced by the most efficient isolate; and (iii) chemically characterize VOCs produced by the most efficient isolate using SPME-GC/MS analysis.The main objective of this research is to study the chemical composition of the principal volatile organic compounds (VOCs) of B. bassiana in the NCBI database using Basic Local Alignment Search Tool software (BLAST)  [B. bassiana , amplicons with a nucleotide length of about 330 bp. The DNA extracted from the same five isolates and amplified with ITS5/ITS4 for rRNA produced amplicons with a nucleotide length of about 600 bp. No amplification was observed in the case of the negative control. The amplicons were directly sequenced , and the obtained sequences were compared with those available in the GenBank nucleotide archive, showing a high similarity percentage (97.29%) with the sequences AB829899, AB829898, and CP045886.1, and those available for MD, USA) . The fivbassiana .B. bassiana had antagonistic effects against most tested bacterial strains, as illustrated in Bacillus cereus and Clavibacter michiganensis, a moderate effect against B. megaterium and a low effect against Xanthomonas campestris and Pseudomonas fluorescens. This isolate did not show any activity against P. aeruginosa  were more able to inhibit the growth of most tested bacterial strains than the endocellular (Endo-ME)  . In partB. bassiana was evaluated against both the grown-visible colonies (GVC) and aqueous suspension (AQS) of each tested bacterial strain. The results of an in vitro bioactivity assay demonstrated that the studied isolate of B. bassiana (UniB2439-3) produced bioactive volatile metabolites that were able to significantly reduce the growth of tested bacterial strains compared to tetracycline (positive control). In particular, the efficacy of the produced volatile substances was high against the AQS of all tested bacterial strains, higher than GVC (B. megaterium (G+ve) and P. fluorescens (G−ve), estimated at 77.5 and 52.5%, respectively. On the other hand, the highest antibacterial activity in the case of AQS was observed against B. megaterium (G+ve) and P. aeruginosa (G−ve), estimated at 92.0 and 87.5%, respectively.The in vitro antibacterial activity of the volatile metabolites eventually emitted by than GVC . In addiB. bassiana UniB2439-3 was illustrated in B. bassiana UniB2439-3 are listed. The most dominant principal compounds, followed by their relative area percentage (R.A.%), are as follows: (i) nitrous oxide (27.57%), (ii) ethanol (4.69%), (iii) butanal, 3-methyl (1.32%), (iv) 2,4-dimethyl-1-heptene (0.63%), (v) octane, 4-methyl (1.99%), and (vi) β-elemene (6.98%)  a–f. The The eventual fragmentation of the acquired volatile metabolites, as described here, is also shown in Beauveria, one of the most studied genera among entomopathogenic fungi, has various biological applications as a growth-promoting agent or insecticide [Research has been conducted recently to overcome the multi-drug-resistant (MDR) microorganisms to different antibiotics and chemotherapeutic agents . Hence, ecticide ,10,31,32Exo-ME against C. michiganensis and the equal activity of both extracts against X. campestris, it would be beneficial to consider the potential synergistic effects of combining the two extracts in future studies.The results revealed that both extracts are less effective than the control (tetracycline); nevertheless, they can be regarded as hopeful and prospective antimicrobial agents or as alternatives for synthetic pesticides. On the other hand, considering the higher activity of B. bassiana, an endophyte for tomato and chili pepper, and observed that the majority of the studied native strains were able to colonize tomato and chili pepper tissues and showed a promising antagonistic effect against B. cinerea.On the other hand, Barra-Bucarei et al.  studied B. bassiana to produce several volatile metabolites with possible antimicrobial effects is in agreement with previous bibliographic research investigating its antagonistic effect against several phytopathogens [Beauveria produced some interesting metabolites, such as oosporein, beauvericin, bassianolide, bassianin, beauveriolide, bassiacridin and cyclosporine, with notable insecticide and antimicrobial actions [The capacity of athogens ,17,33. I actions ,38,39,40B. bassiana, several studies revealed that beauvericin and oosporein evidenced remarkable antibiotic and antifungal properties [B. bassiana and confirmed to have antimicrobial activity and anti-tumor effects, especially against human leukemia. In another study, conducted by Manning and Wyatt [Among the different bioactive metabolites produced by operties ,40, whicoperties  reportednd Wyatt , the resB. bassiana produces a variety of important VOCs, such as: (i) butanal, 3-methyl; (ii) 2,4-dimethyl-1-heptene; and (iii) octane, 4-methyl. These findings are in agreement with those of Chiron and Michelot [Our findings from the SPME-GC/MS analysis showed that Michelot , who expMichelot .The possible mechanism of volatile antimicrobial effects, in general, may be explained by the potential of volatiles to flow across a structure of soil gaps since they are active in both gaseous and liquid phases and have the potential of revolatization after flowing through water-saturated pores . HoweverEnterobacter agglomerans [Coccoloba peltate, showed notable antioxidant and cytotoxic effects.In particular, 2,4-dimethyl-1-heptene showed antimicrobial activity, as reported by Mannaa and Kim . In addilomerans . Salih elomerans  also repBeauveria isolate. β-elemene was identified for the first time in 1994 in a dry rhizome extract from Curcuma phaeocaulis, C. kwangsinensis, and C. wenyujing [Proteus vulgaris [Mycobacterium tuberculosis, as reported by Sieniawska et al. [Our obtained results also detected the presence of an important sesquiterpene compound identified as β-elemene , 1S- among the detected VOC substances from the studied enyujing . In addivulgaris . β-elemevulgaris , and in vulgaris . The sama et al. . dprE1 and clgR genes, which are responsible for cell wall synthesis and cell membrane preservation, respectively. Generally, the mechanism of the antimicrobial activity of several terpenes is highly related to their lipophilic properties, which enable them to dissolve in the phospholipid layers of a microbial cell membrane . ParticuSome recent studies reported on the promising cytotoxic effects of β-elemene, which can inhibit cell proliferation, arrest cell cycle, and induce cell apoptosis or autophagy . Β-elemeBeauveria bassiana  were isolated from different rhizospheric soil samples of Actinidia spp. and identified based on their morphological features and molecular basis. For molecular identification, the total gDNA was extracted, and a partial part of β-tubulin and ribosomal DNA genes were amplified using the universal primers Bt2a (5′-GGTAACCAAATCGGTGCTGCTTTC-3′)/Bt2b (5′-ACCCTCAGTGTAGTGACCCTTGGC-3′) [Five strains of TGGC-3′) , and ITSTGGC-3′) . The obtTGGC-3′) . B. bassiana was evaluated against some pathogenic bacteria. All tested isolates were obtained from the pure cultures conserved in the collection of SAFE and identified using morphological and molecular methods. The tested bacteria strains are listed in The antagonistic activity of the five studied isolates of B. bassiana was deposited in the center of the King B nutrient media (KB) Petri dish and incubated for 16 h at 22 ± 2 °C. Successively, a suspension of soft-agar (0.7%) of each tested bacteria at 108 CFU/mL was sprayed over the plates using Eco-Spray Ecological Aerosol . All plates were incubated at 30 °C for 24 h. Two KB plates inoculated only with each tested bacteria were used as a negative control. The experiment was run in triplicate, and the diameter of the inhibition zone was measured with a caliber and recorded as the mean  ±  SD (n  =  3). The antagonistic bacterial activity percentage (ABP%) was calculated using Equation (1): An antibacterial assay was carried out as described by Elshafie et al. . A fungaB. bassiana was selected for successive studies. For this purpose, 2 mL of the fungal suspension (106 spores/mL) of the above isolate was used to inoculate 500 mL SDY broth nutrient media and then incubated for 7 days at 25 °C in agitation (180 rpm). Both Exo-ME and Endo-ME were extracted from the broth culture after the incubation period. On the basis of the preliminary antagonistic assay, the most efficient isolate (UniB2439-3) of Endo-ME, the incubated broth culture was centrifuged at 40,000× g for 15 min, and the pellet (2 g) was collected, resuspended in 50 mL of Limonene  and shaken for 2 h; after this, the solvent was evaporated using the rotary-evaporator . The residue was resuspended in 2 mL of sterile distilled water (SDW), following the Solid Phase Extraction (SPE) method using a C-18 column , and recovered using 1 mL methanol to reach the final original concentration of (20 mg/mL) [For 0 mg/mL) . Exo-ME, the supernatant (250 mL) obtained from the above centrifugation step was filtered using 0.22 µm  and extracted using a separator funnel containing 250 mL ethyl acetate/ethanol  and shacked for 15 min. The organic phase was filtered through a filter paper  and evaporated using the rotary-evaporator. The dry residue (50 mg) was resuspended in 2 mL SDW, extracted through SPE using a C-18 column, and recovered using 1 mL methanol to reach the final original concentration of (16 mg/mL) [For 6 mg/mL) .The antibacterial activity of both metabolite extracts, compared with the same bacteria strains used for the initial antagonistic assay, is listed in 6 CFU/mL (OD ≈ 0.2 nm) using UV-Spectrophotometer . A total of 4 mL of bacterial suspension mixed with soft agar 0.7%  was poured over each KB plate (Ø 9 cm). Blank discs of 6 mm  were then placed over the plates and 15 µL from each tested metabolite extract (Exo-ME 16 mg/mL and Endo-ME 20 mg/mL) were carefully applied to the discs. Tetracycline (1600 µg/mL) was used as a positive control. The experiment was performed in triplicate, and the antibacterial activity was estimated by measuring the diameter of the inhibition zone in mm ± SDs compared to the positive control. Disc diffusion assay. An antibacterial test of both metabolite extracts produced by the most bioactive isolate UniB2439-3 was carried out following the disc-diffusion method, as described by Elshafie et al.  and SofoB. bassiana (UniB2439-3) was cultured on PDA media (14 mL Petri dishes) and incubated at 22 °C for 96 h. The test was performed according to Wan et al. [B. bassiana in one downward dish of KB (Ø 90 mm), and the tested bacterial strains were singularly inoculated on the upward dish, either by direct colony inoculation or the spread of 50 μL of an aqueous suspension (107 CFU/mL). In brief, the direct inoculation of colonies was carried out using a sterile swab to homogenize the colonies over the KB surface. The concentration of the aqueous bacterial suspension was adjusted using turbidimetry. The chamber was sealed with Parafilm™ and incubated at 37 °C in darkness for 48 h. The antibacterial activity of the eventually produced volatile metabolites was evaluated by measuring the inhibition percentages of GVC and AQS of each tested bacterial strain. The experiment was carried out twice with three replicates. The tested bacterial strains were initially subcultured on 14 mL KB medium in Petri dishes and incubated at 37 °C for 24 h. The most efficient isolate of n et al.  using a Beauveria isolate was inoculated in a glass tube of 10 mL PDA nutrient media and incubated at 22 °C for 5 days in darkness to collect the volatile organic compounds (VOCs) [The fresh culture (96 h) of the selected s (VOCs) . The eveThe SPME fiber coated with 100 μm of non-grafted poly (dimethylsiloxane) phase , was conditioned for 1 h at 250 °C in a stream of helium. A blank run was performed after each analysis to confirm that no residual compounds were polluting the fiber or the column. The fiber was later introduced to the injection port of an HP6890 plus gas chromatograph equipped with a Phenomenex Zebron ZB-5 MS capillary column (30 m × 0.25 mm ID × 0.25 μm film thickness). An HP 5973 mass-selective  was used as a detector, whereas helium at 0.8 mL/min was used as a carrier gas. The injection port, equipped with a glass insert , was split at 250 °C. A desorption time of 1.0 min was used. The detector was maintained at 230 °C. Oven was maintained at 80 °C for 3 min, then the temperature was increased to 250 °C (20 °C/min) for 10 min. All the analyses were performed in triplicate. The chromatograms obtained from the total ion current were integrated without any correction for coelutions, and the results were expressed as a percent of the total area of peaks . All peaTukey B Post-Hoc multiple comparison test was used to evaluate the significance level with a probability of p < 0.05.The obtained results for the biological assays were statistically analyzed, applying one-way ANOVA using the Package for the Social Sciences (SPSS) version 13.0 . B. bassiana, apart from being a notable entomopathogenic fungi or biocontrol agent against some phytopathogens, by itself or through its bioactive metabolites. In particular, B. bassiana or its bioactive metabolites could also be used efficiently to control several bacteria in the agronomic field, where the use of antibiotics is forbidden, especially in organic farming. In addition, B. bassiana could also be a useful biocontrol agent against MDR microorganisms to different antibiotics, which are considered a dominant medical problem worldwide. The obtained results from the current research concluded that B. bassiana UniB2439-3 was able to produce some interesting VOCs, such as β-elemene, which has been reported previously to have a strong antimicrobial effect against several pathogenic microorganisms. The ability of B. bassiana to produce the above-mentioned metabolites can underline its antagonistic activity against several phytopathogens, as reported previously in the bibliographic research. Future studies remain necessary to evaluate the in vivo antimicrobial activity of each identified bioactive VOC from B. bassiana against serious phytopathogens, considering that the use of antibiotics is forbidden in agriculture in many countries. Therefore, the search for possible natural alternatives as efficient antimicrobial agents remains necessary.