Roteins hydrolyzed from melinjo seeds (Gnetum gnemon) at green (GM), yellow (YM) and red (RM) stages of maturity were studied for their effectiveness in antioxidant and antidiabetic activities. The seed protein extract was hydrolyzed using alcalase 2.4L, and the resulting hydrolysates with the highest degree of hydrolysis, protein profile, and the most potent contributors to antioxidant and invitro antidiabetic activities were identified. The degree of hydrolysis value of hydrolysates ranged from 52-84%, and the SDS-PAGE protein profile showed two distinct bands in which the band with molecular weight of 30 kDa degraded more intensively. Antioxidant capacity was measured using different standard methods, including radical cation 2,2-azinobis-(3-ethylbenzothizoline-6-sulphonate) (ABTS•+) assay, hydroxyl radical (OH•), and superoxide anion (O2•-) scavenging. The green hydrolysate (GMH) had significantly higher (p<0.05) free radical scavenging (ABTS•+, OH•, and O2•-) activities than that of the yellow hydrolysate (YMH) and red hydrolysate (RMH). However, invitro antidiabetic testing was performed based on the inhibitory activity of α-amylase and α-glucosidase. GMH was found to be more effective than YMH and RMH. These results showed that the antioxidant and antidiabetic activity in hydrolyzed GM protein has high potential to be utilized as natural nutraceuticals.

This study explores the production of prebiotic xylooligosaccharide (XOS) from cassava pulp waste and its effectiveness for the growth of Lactobacillus acidophilus (L. acidophilus). We successfully produced and characterized XOS from cassava pulp xylan using a Bacillus sp. endo-β-1,4-D-xylanase. The XOS was added to modify the MRS medium (MRSm) in various concentrations (0, 1, 3 and 5%) in which the L. acidophilus was inoculated. The growth of L. acidophilus was observed every 12 h for 2 days, and the fermentation products were analyzed for pH, sugar content, and short-chain fatty acids (SCFA) in terms of types and amount. The study showed that L. acidophilus grew well in MRSm. The optimum XOS concentration in MRSm was 5%, indicated by the highest growth of L. acidophilus (8.61 log CFU mL⁻¹). The profile of SCFA products is 14.42 mM acetic acid, 0.25 mM propionic acid, 0.13 mM isobutyric acid, 0.41 mM n-butyric acid, 0.02 mM n-valeric acid, 0.25 mM isovaleric acid, and 25.08 mM lactic acid.

Coffee is the second most common trade commodity in the world after petroleum. The coffee industry generates large amounts of waste in the form of coffee peels. Coffee peel waste consist of lignocellulose containing hemicellulose and other chemical compounds. The objective of this research was to extract xylan, the main component of hemicellulose from coffee waste, and to utilize the xylan in the production of xylooligosaccharide (XOS). Xylan was extracted from coffee waste using NaOH solution and neutralized by HCl 6 M. Afterward, xylan was precipitated using ethanol. Various NaOH concentrations (4, 8, 12 and 16 % w/v) were used to obtain the xylan. NaOH solution with a concentration of 12 % results 43 % extraction of xylan from coffee waste. Xylan obtained from the extraction was hydrolyzed using endo-β-1,4-xylanase from Bacillus sp. to produce XOS. The incubation time of enzyme-substrate was observed at 40 oC, pH 5 and enzyme dose of 23.6 U. Thin layer chromatography results showed that the hydrolyzed products of xylan are XOS with composition xylobiose (X2), xylotriose (X3), xylotetraose (X4) and xylopentaose (X5). LC-MS studies revealed that X2 is the dominant product with the concentration of 6.00 ppm. This research demonstrates the potential to utilizate coffee peel waste as a source of xylan for the production of XOS.

Red dragon fruit peel can be used as a source of energy (bioethanol) because it contained carbohydrates like cellulose. The process of making bioethanol is carr