title: Anti-hyperglycemic activity of an aqueous extract from flower buds of Cleistocalyx operculatus (Roxb.) Merr and Perry.
abstract: A screening of 5 plants used for making drinks in Vietnam revealed a Cleistocalyx operculatus (Roxb.) Merr and Perry flower bud extract to have the highest inhibitory activity against the alpha-glucosidase enzyme. The anti-hyperglycemic effects of an aqueous extract from flower buds of Cleistocalyx operculatus (CO), a commonly used material for drink preparation in Vietnam, were therefore investigated in vitro and in vivo. In vitro, the CO extract inhibited the rat-intestinal maltase and sucrase activities, with IC50 values of 0.70 and 0.47 mg/ml, respectively. These values are lower than those for a guava leaf extract (GE; IC50 0.97 and 1.28 mg/ml, respectively). Postprandial blood glucose testing of normal mice and STZ-induced diabetic rats by maltose loading (2 g/kg body weight (bw)) showed that the blood glucose reduction with CO (500 mg/kg bw) was slightly less than that with acarbose (25 mg/kg bw) but was more potent than that with GE (500 mg/kg bw). In an 8-week experiment, the blood glucose level of STZ diabetic rats treated with 500 mg of CO/kg bw/day was markedly decreased in comparison with that of non-treated diabetic rats. Consequently, CO is considered to be a promising material for preventing and treating diabetes.
authors.affiliation: Department of Food and Nutrition, Japan Women's University, Japan.
authors.forename: Truong Tuyet
authors.initials: TT
authors.lastname: Mai
authors.forename: Nguyen Van
authors.initials: NV
authors.lastname: Chuyen
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D003920:Diabetes Mellitus / Q000097:blood / Q000139:chemically induced / Q000188:drug therapy; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D035264:Flowers / Q000737:chemistry*; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D008320:Maltose / Q000494:pharmacology; D051379:Mice; D010636:Phenols / Q000737:chemistry / Q000494:pharmacology; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D059808:Polyphenols; D052596:Pongamia / Q000737:chemistry*; D051381:Rats; D013393:Sucrase / Q000494:pharmacology; D013997:Time Factors; D000520:alpha-Glucosidases / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D004791:Enzyme Inhibitors; D005419:Flavonoids; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D008320:Maltose; D000520:alpha-Glucosidases; D013393:Sucrase