title: Enhancing vitamin B12 content in soy-yogurt by Lactobacillus reuteri.
abstract: More attention from the aged and vegetarians has been paid to soy-product due to its taste, easy digestibility, as well as the association with health. However, soy-product has a defect of low vitamin content, mainly the water-soluble vitamin B12. This study was to investigate co-fermentation of glycerol and fructose in soy-yogurt to enhance vitamin B12 production by Lactobacillus reuteri. After a serial combination experiments, the co-fermentation was confirmed to enhance the production of vitamin B12 up to 18 μg/100mL. Both supplementations induced the expression of cobT and cbiA and functioned to balance the redox reaction. Meanwhile, high content of fructose supplementation reduced the production of vitamin B12 and suppressed expression of cobT in bacteria. It was proved that the vitamin B12 content of this soy-yogurt is higher than other fermented soybean based food and thus can be served as an alternative food for the aged and vegetarians.
authors.affiliation: Zhejiang Gongshang University, Key Laboratory for Food Microbial Technology of Zhejiang Province, No. 18 Xuezheng Str., Hangzhou, Zhejiang Province 310018, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Gu
authors.affiliation: Zhejiang Gongshang University, Key Laboratory for Food Microbial Technology of Zhejiang Province, No. 18 Xuezheng Str., Hangzhou, Zhejiang Province 310018, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Zhejiang Gongshang University, Key Laboratory for Food Microbial Technology of Zhejiang Province, No. 18 Xuezheng Str., Hangzhou, Zhejiang Province 310018, China.
authors.forename: Dafeng
authors.initials: D
authors.lastname: Song
authors.affiliation: Zhejiang Gongshang University, Key Laboratory for Food Microbial Technology of Zhejiang Province, No. 18 Xuezheng Str., Hangzhou, Zhejiang Province 310018, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.affiliation: Zhejiang Gongshang University, Key Laboratory for Food Microbial Technology of Zhejiang Province, No. 18 Xuezheng Str., Hangzhou, Zhejiang Province 310018, China. Electronic address: zhuxuan@mail.zjgsu.edu.cn.
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhu
mesh_terms: D005285:Fermentation; D005516:Food Microbiology; D005632:Fructose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D007778:Lactobacillus / Q000378:metabolism; D052200:Limosilactobacillus reuteri / Q000378:metabolism*; D013025:Glycine max / Q000382:microbiology*; D013649:Taste; D014805:Vitamin B 12 / Q000032:analysis / Q000096:biosynthesis*
chemical_list: D005632:Fructose; D014805:Vitamin B 12; D005990:Glycerol
keywords: Fructose; Glycerol; Lactobacillus reuteri; Vitamin B(12); cobT