Environmental-friendly technologies for the production of antioxidant xylooligosaccharides from wheat chaff.

Ultrasound irradiation and enzymatic hydrolysis were applied for the production of antioxidant xylooligosaccharides from wheat chaff. To facilitate enzyme action, 3% (w/w) suspension of raw material was pretreated by ultrasound at 25Hz, 540W for 10min. Ultrasound treatment released xylooligosaccharides with predominant xylotriose into liquid fraction which expressed 1.03±0.01 (μmolAAE/g) ABTS radicals-scavenging activity. Endo-xylanase action on pretreated wheat chaff released 21.76±1.42 and 32.3±0.75mg reducing sugars equivalents/g after 24h when applied at dosages 0.15 and 0.3U/g. respectively. With increase in reaction time portion of xylotriose and xylotetraose in hydrolysates was increase relatively to xylopentose as well as quantities of xylose and glucose. Extremely significant inverse correlation between monosaccharides/oligosaccharides ratio and ABTS radical-scavenging activity was determined. Results indicated potential of environmental friendly ultrasound and enzymatic technologies for the production of xylooligosaccharides from wheat chaff for potential food application.