Total Phenol and Antioxidant from Seed and Peel of Ripe and Unripe of Indonesian Sugar Apple ( Annona squamosa L . ) Extracted with Various Solvents Deva
Study on total phenol and antioxidantactivity ofsugar apple fruits of various solvent, part of fruits, and level of ripening. Solvent extraction used were 80% (v/v) methanol, 50% (v/v) acetone, boiling water, and 50% (v/v) ethanol. Part of fruits thatbeen used for samples were seed and peel which are normally by products of sugar apple processing, level of ripening were unripe, and ripe sugar apple fruits. Total phenol was determined by Folin-ciocalteau method. Total antioxidant was quantified by 1,1-diphenyl-2picrylhydrazyl(DPPH) method.Therewas a difference in type of solvent, part of fruits, and level of ripeningon total phenol and antioxidant concentration of sugar apple fruits. Seeds have higher total phenol concentration than peels of this fruits. Unripe sugar apple fruits have higher total phenol and antioxidant than ripe fruit. The best solvent for phenol extraction was ethanol 50%butthe best solvent for antioxidant extraction was acetone 50%.
Evolution of Antibacterial Activity of Various Solvents Extracts of Annona Squamosa Fruit
This research project was designed to evaluate the antibacterial activity of three different portions (pulp, peel, seeds) of Annona squamosa fruit using three different extraction solvents (water, ethanol, and acetone). The experiment performed by using agar well diffusion method against Gram-positive human pathogenic bacteria, Staphylococcus aureus and Gram-negative bacteria, Klebsiella pneumoniae, and Escherichia coli and each organism showed different patterns of inhibition zones. Antibacterial activity of various solvent extracts of the pulp showed noticeable inhibitory activity against almost all the tested pathogens except K. pneumoniae who was resistant to water extract of pulp.  Although, different solvents extracts of peel were found to be efficient in inhibiting the test pathogens, ethanolic extract of peel exhibited the best antibacterial activity against all the test pathogens in this study. Maximum inhibition activity was found with the peel ethanolic extract against E.coli and K. pneumonia, followed by S. aureus at crud extract concentration of 50 mg ml -1 , which is comparable to the inhibition zones of the standard antibiotic ( Tetracycline and Ceftriaxone 100mg ml -1 ) used in this study. The water extract of peel also exhibited fairly good antibacterial activity against E. coli approximately similar to the ethanolic extract. Conversely, S. aureus and K. pneumoniae showed complete resistance against water extract of peel. Regarding seeds bactericidal abilities, the water and acetone extracts of seeds showed remarkable inhibitory action against K. pneumonia followed by the water extract against E.coli. None of the test pathogens showed inhibition of growth response to seed ethanolic extract. In conclusion, antibacterial ability of different portions of A .squamosa fruit extracts against different types of bacteria used in this experiment signified their remarkable potential for exploration and using effective antibacterial agents from natural resources to inhibit the growth of different types of pathogenic bacteria.
Investigation of plant extracts for the protection of processed foods against lipid oxidation. Comparison of antioxidant assays based on radical scavenging, lipid oxidation and analysis of the principal antioxidant compounds
Abstract Antioxidant activities of plant extracts from spices, coffee, tea, grape skin, and tomato peel slurry were evaluated using a number of analytical methods including the quantification of principal compounds. Similar rankings in the activities of these extracts were obtained by evaluating their efficiencies as scavengers of stable free radicals: Fremy's salt, galvinoxyl or α,α-diphenyl-β-picrylhydrazyl (DPPH). Similar results were obtained with the lipid oxidation assays based on thermal acceleration (formation of conjugated dienes in methyl linoleate at 40  °C or the Rancimat test at 100  °C with lard). Rankings of the extract activity obtained by scavenging of hydroxyl radicals generated in the Fenton reaction were similar to those obtained by an oxygen consumption assay with linoleic acid as substrate and metmyoglobin as catalyst. However, the results of the latter two assays differed from those of the other assays. In the overall ranking, coffee and rosemary extracts were amongst the most potent extracts whereas the tomato peel slurry showed no activity.