Preparation and application of natural polysaccharide from by-product of wheat processing

Wang Lili, Zhong Kui, Tong Litao, Liu Liya, Zhou Xianrong, Zhou Sumei*

Agro-Products Processing Science & Technology (IAPPST), Chinese

Academy of Agricultural Sciences (CAAS) , China

Arabinoxylan (AX) is a kind of natural non-starch, non-cellulose polysaccharide of cereal crops, such as wheat, corn, sorghum, rye et al, which is especially rich in wheat (4.5%-8.5%). As the structure polysaccharide of cell wall, AX mainly exists in wheat bran, the abundant and cheap by-product of wheat processing, and it is very difficult to be extracted by water in mild conditions. So the preparation methods of the AX from wheat bran were studied in the research. Firstly, wheat bran from flour mill was pre-treated by washing, acid leaching and drying to remove starch, protein and phytic acid. The cleaned wheat bran was treated by alkali solution and xylanase-contained solution respectively to prepare two kinds of AXs-AX_A and AX_X, which were different not only in the contents of protein and ferulic acid, but also in their molecular weights (Mw). According to previous reports, wheat bran AXs may have the both activities of dietary fibre and bioactive polysaccharide, then the prebiotic and antitumor activities of the obtained AXs were evaluated and compared. The results showed that both AXs significantly inhibited the growth of mouse transplantable sarcoma S180 (P <0.05, P < 0.01), and stimulated the growth of bifidobacterium and lactobacillus compared with the control. The higher activities were from the AX_X group. According to the results, it was concluded that AXs from wheat bran could be developed as new kind of functional ingredients with prebiotic and antitumor activities.