title: Isolation and characterization of an α-glucosidase inhibitor from Musa spp. (Baxijiao) flowers.
abstract: The use of α-glucosidase inhibitors is considered to be an effective strategy in the treatment of diabetes. Using a bioassay-guided fractionation technique, five Bacillus stearothermophilus α-glucosidase inhibitors were isolated from the flowers of Musa spp. (Baxijiao). Using NMR spectroscopy analysis they were identified as vanillic acid (1), ferulic acid (2), β-sitosterol (3), daucosterol (4) and 9-(4'-hydroxyphenyl)-2-methoxyphenalen-1-one (5). The half maximal inhibitory concentration (IC50) values of compounds 1-5 were 2004.58, 1258.35, 283.67, 247.35 and 3.86 mg/L, respectively. Compared to a known α-glucosidase inhibitor (acarbose, IC50=999.31 mg/L), compounds 3, 4 and 5 showed a strong α-glucosidase inhibitory effect. A Lineweaver-Burk plot indicated that compound 5 is a mixed-competitive inhibitor, while compounds 3 and 4 are competitive inhibitors. The inhibition constants (Ki) of compounds 3, 4 and 5 were 20.09, 2.34 and 4.40 mg/L, respectively. Taken together, these data show that the compounds 3, 4 and 5 are potent α-glucosidase inhibitors.
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China. shengzhanwu100@163.com.
authors.forename: Zhanwu
authors.initials: Z
authors.lastname: Sheng
authors.affiliation: Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, China. daihaofu@itbb.org.cn.
authors.forename: Haofu
authors.initials: H
authors.lastname: Dai
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China. pansiyi@mail.hzau.edu.cn.
authors.forename: Siyi
authors.initials: S
authors.lastname: Pan
authors.affiliation: College of Food Science and Technology, Hainan University, Haikou 570228, China. huiwang2013@163.com.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Food Science and Technology, Hainan University, Haikou 570228, China. yingyinghu2014@163.com.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Hainan Key Laboratory of Banana Genetic Improvement, Haikou Experimental Station, Chinese Academy of Tropical Agricultural Sciences, Haikou 570101, China. zjwhma@163.com.
authors.forename: Weihong
authors.initials: W
authors.lastname: Ma
mesh_terms: D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry; D035264:Flowers / Q000737:chemistry*; D001411:Geobacillus stearothermophilus; D065089:Glycoside Hydrolase Inhibitors / Q000737:chemistry / Q000302:isolation & purification; D028521:Musa / Q000737:chemistry*; D000520:alpha-Glucosidases / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D065089:Glycoside Hydrolase Inhibitors; D000520:alpha-Glucosidases