Evaluation of the functional properties of short-chain xylooligosaccharides obtained from the enzymatic hydrolysis of bamboo culm

Abstract

Xylooligosaccharides (XOS) are important oligomers of xylose. XOS have received particular interest in recent years from the food and pharmaceutical industries due to their functional properties associated with fighting diseases and maintaining health. Therefore, the objective of this work was to evaluate the in vitro digestibility, prebiotic, and antioxidant effects, as well as the production of short-chain fatty acids from short-chain XOS obtained from enzymatic hydrolysis of the bamboo culm. The xylan extracted from the bamboo culm was subjected to enzymatic hydrolysis at an endoxylanases concentration of 7.5 mg protein/g xylan at 50 °C and pH 5.0 for 24 h. The extract obtained showed a high concentration of XOS, approximately 5 g/L, composed of xylobiose (2.39 g/L), xylotriose (1.31 g/L), xylotetraose (0.567 g/L), xylopentose (0.223 g/L) and xylohexose (0.18 g/L). The in vitro digestibility tests indicated that the XOS presented a high and desirable resistance to digestion, considering that 97.65% of the XOS remained intact in the simulated intestinal phase. The XOs showed an expressive prebiotic effect, promoting the growth of Lactobacillus acidophilus and Bifidobacterium bifidum, fermenting the XOS and producing short-chain fatty acids, highlighting acetate, propionate, and butyrate. These organic acids play important roles in fighting inflammation, protecting brain functions, and inhibiting the development of cancer cells and pathogens. XOS showed a high total antioxidant capacity, eliminating 73.5% of the DPPH free radicals. Finally, the XOS produced from bamboo culm has great prebiotic potential and excellent antioxidant activity and can be applied to food and pharmaceutical products.