Isolation and prebiotic activity of water-soluble polysaccharides fractions from the bamboo shoots (Phyllostachys praecox).

The water-soluble polysaccharides from bamboo shoots (Phyllostachys praecox) (WBP) were isolated, and the characterizations as well as prebiotic activities were investigated. The yield of WBP was 7.58±0.31% under optimal hot-water extraction conditions. Two fractions, i.e., WBP-1 and WBP-2 with molecular weight of 83.50kDa and 80.08kDa, respectively, were purified by chromatography. Both the polysaccharides fractions were identified as heteropolysaccharides-protein complexes composed of 15 kinds of common amino acids in protein part and rhamnose, arabinose, xylose, mannose, glucose and galactose in different molar ratios in polysaccharide part. The existence of α- and β-glycosidic linkages between the sugar units was confirmed by FTIR and NMR spectra. Compared with the blank control and the reference of FOS, WBP-1 and WBP-2 significantly increased the numbers of Bifidobacterium adolescentis and Bifidobacterium bifidum (P<0.05), which contributed to the production of organic acids, suggesting that the polysaccharides have potential prebiotic properties.