title: Effects of sources of carbon and nitrogen on production of α-glucosidase inhibitor by a newly isolated strain of Bacillus subtilis B2.
abstract: This study examined production of α-glucosidase inhibitors by Bacillus subtilis B2 in Luria-Bertani (LB) fermentation with okara, soy powder, starch or pectin as additional source of carbon and nitrogen. All the fermentation broths of B. subtilis B2 exhibited gradual increase in α-glucosidase inhibitory activity during the fermentation process with or without supplemented source of carbon or nitrogen. Addition of okara into the LB medium greatly enhanced the strength (nearly twice as much of that without okara supplement) of α-glucosidase inhibitory activity of fermentation broth. The α-glucosidase inhibitory activity of B. subtilis B2 fermentation broth was positively correlated (p<0.05) with the bacterial populations grown in LB medium containing okara. Glucose and sucrose were not detected in LB medium during the entire fermentation process and were both reduced drastically in media containing okara, soy powder, starch or pectin after 6days of fermentation. The fermented LB medium containing okara by B. subtilis B2 possessed very strong α-glucosidase inhibitory activity and contained little glucose and sucrose, suggesting that fermentation of B. subtilis B2 in LB added with okara might be considered as a strategy for preparing functional foods for diabetic patients.
authors.affiliation: College of Food Science and Nutritional Engineering, Post Box 40, China Agricultural University, East Campus, No. 17 Qinghua Dong Lu, Haidian District, Beijing 100083, China.
authors.forename: Yun-Ping
authors.initials: YP
authors.lastname: Zhu
authors.affiliation: College of Food Science and Nutritional Engineering, Post Box 40, China Agricultural University, East Campus, No. 17 Qinghua Dong Lu, Haidian District, Beijing 100083, China.
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Yin
authors.affiliation: College of Food Science and Nutritional Engineering, Post Box 40, China Agricultural University, East Campus, No. 17 Qinghua Dong Lu, Haidian District, Beijing 100083, China.
authors.forename: Yong-Qiang
authors.initials: YQ
authors.lastname: Cheng
authors.affiliation: Food Science and Technology Division, Japan International Research Center for Agricultural Sciences, Ibaraki 305-8686, Japan.
authors.forename: Kohji
authors.initials: K
authors.lastname: Yamaki
authors.affiliation: Food Science and Technology Division, Japan International Research Center for Agricultural Sciences, Ibaraki 305-8686, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Mori
authors.affiliation: Seafood Research and Education Center, Oregon State University, Oregon 97103-3420, USA.
authors.forename: Yi-Cheng
authors.initials: YC
authors.lastname: Su
authors.affiliation: College of Food Science and Nutritional Engineering, Post Box 40, China Agricultural University, East Campus, No. 17 Qinghua Dong Lu, Haidian District, Beijing 100083, China. Electronic address: llt@cau.edu.cn.
authors.forename: Li-Te
authors.initials: LT
authors.lastname: Li
keywords: Bacillus subtilis B2; Fermentation; Okara; α-Glucosidase inhibitor