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Anthracnose is a fungal disease caused by Colletotrichum species that is detrimental to numerous fruit, including soursop and avocado. The use of fungicides to maintain the high quality of fruit creates a potential health risk. One alternative to this problem is the biological control, which has been applied successfully during postharvest. The Bacillus species are one of the most studied biological agents against postharvest pathogens because accomplish their biocontrol performance by producing a variety of metabolites. In this study, we evaluated the activity of metabolites contained in the cell free supernatant, obtained from Bacillus strain B5 culture, against micelial growth and spore germination of two virulent strains of C. gloeosporioides isolated from soursop and avocado. On the basis of 16S rDNA gene sequence analysis, this strain was identified as Bacillus atrophaeus. A preventive treatment using cell free supernatant, reduced severity and incidence of anthracnose disease on harvested soursop and avocado fruit. B. atrophaeus strain B5 harbors genes involved in the production of antibiotics such as surfactin, bacillomycin and iturin, which could be contributing to the efficiency of the preventive treatment during postharvest. The antagonistic role of metabolites contained in the cell free supernatant against anthracnose disease, provide a new approach by which to attack this problem and can help reduce the use of chemical pesticides, environmental pollution, leading to the safer fruit preservation.

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Glutelin fraction from cocoa almond was hydrolyzed with alcalase for the production of hydrolysates. These were then fractionated by ultrafiltration to obtain peptides with a molecular weight (M W ) lower than 3000 Da. The antioxidant activity (AOX) of the hydrolysates and peptides was assessed using 1,1diphenyl-2-picrylhydrazyl (DPPH • ), 2,2´-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS •+ ), and oxygen radical absorbance capacity (ORAC) assays. Ultrafiltered peptide fraction with the highest AOX was purified by size exclusion chromatography, by which four main peaks were identified with a M W between 535 and 2959 Da. The peptide fraction P1 (M W = 2959 Da) showed the highest capacity to scavenge DPPH • and ABTS •+ radicals with radical scavenging activity DPPH • and ABTS •+ with EC 50 values of 237.48 and 19.29 µg/mL, respectively, which were similar to those obtained with glutathione. These results show that enzymatic treatment of cocoa glutelin comprises an attractive bioprocess for the production of peptide fractions with AOX, which could be included in the design of functional foods; moreover, they show an alternative use of cocoa.Actividad antioxidante de hidrolizados y fracciones peptídicas de glutelina de la semilla de cacao (Theobroma cacao L.) RESUMENLa fracción de glutelina de la almendra de cacao se hidrolizó con alcalasa para la producción de hidrolizados, los cuales se fraccionaron por ultrafiltración para obtener péptidos con un peso molecular (M W ) menor a 3000 Da. La actividad antioxidante (AOX) de los hidrolizados y péptidos se evaluó mediante los ensayos de 1,1-diphenyl-2-picrylhydrazyl (DPPH • ), 2,2´-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS •+ ) y capacidad de absorción del radical oxígeno (ORAC). La fracción peptídica obtenida por ultrafiltración con la mayor AOX se purificó por cromatografía de exclusión molecular, mediante la cual se identificaron cuatro principales picos con un M W entre 535 y 2959 Da. La fracción peptídica P1 (M W = 2959 Da) mostró la mayor actividad reductora de radicales DPPH • y ABTS •+ con valores EC 50 de 237.48 y 19.29 µg/mL, respectivamente, los cuales fueron similares a los obtenidos con glutatión. Estos resultados muestran que el tratamiento enzimático de glutelina de cacao es un bioproceso atractivo para la producción de fracciones peptídicas con AOX, que podrían incluirse en el diseño de alimentos funcionales. Además, proporcionaría un uso alternativo del cacao.

The interest in extracting kafirins (KAF), the main storage protein from sorghum grain has recently increased due to its gluten-free content and the significant scientific evidence showing the health benefits of the bioactive peptides from cereal grains in human diets. The objectives were to obtain the highest percentage of KAF extraction using amyloglucosidase as pretreatment to increase the extraction yield and predict the bioactive peptides in the KAF. In this study, pretreatments with amyloglucosidase increased the extraction yield of KAF compared with extraction methods using only ethanol and sodium metabisulfite. Two protein fragment sequences were identified from KAF extract and were evaluated for potential bioactive peptide using the BIOPEP-UWM database, which suggest that KAF proteins from white sorghum may be considered as good precursors of dipeptidyl peptidase-inhibitor, angiotensin-converting enzyme inhibitor, antioxidant and hypotensive peptides following chymotrypsin, thermolysin, and subtilisin and their combination. Average scores aligned using PeptideRanker confirmed KAF proteins' potential sources of bioactive peptides with over 5 peptides scored over 0.8. In addition, 31 unexplored peptide sequences that could have biological activity were identified. Our results suggest that KAF can be used in the peptide productions with potential biological activity and beyond.

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