Functional food applications of dextran from Weissella cibaria RBA12 from pummelo (Citrus maxima)

- Dextran-RBA12 is composed of 97% α-(1 → 6) linkages in the main chain and 3% α-(1 → 3) branched linkages.
- Dextran-RBA12 showed higher prebiotic activity score with probiotic Bifidobacterium spp than Lactobacillus spp.
- Dextran-RBA12 showed lower hydrolysis by artificial gastric juice, α-amylase and intestinal fluid than that of inulin.
- Dextran-RBA12 was efficiently produced in sourdough using wheat bran and rye bran.

Weissella cibaria RBA12 isolated from pummelo from Northeast India produces a dextran composed of 97% α-(1 → 6) linkages in the main chain and 3% α-(1 → 3) branched linkages. The in vitro prebiotic activity of dextran-RBA12 was explored. Dextran-RBA12 displayed enhanced growth of probiotic Bifidobacterium and Lactobacillus spp., and controlled growth of non-probiotic enteric bacteria. Dextran-RBA12 showed superior resistance to physiological barriers with a maximum hydrolysis of 0.51%, 0.31% and 0.24% by artificial gastric juice, α-amylase and intestinal fluid, respectively, whereas compared to maximum hydrolysis of 25.23%, 19.13% and 6%, respectively after 5 h of incubation shown by commercial prebiotic inulin. The production of dextran from Weissella cibaria RBA12 in sourdough prepared from whole wheat flour, wheat bran and rye bran showed the highest dextran of 3.26 ± 0.12% d.w. in rye bran. The overall study summarized that dextran-RBA12 can be used as a prebiotic and also can be easily produced in sourdough.