Methyl caffeate as an alpha-glucosidase inhibitor from Solanum torvum fruits and the activity of related compounds

• Published in: Bioscience, biotechnology, and biochemistry biotechnology, and biochemistry, 2010, Vol.74 (4), p.741-745
• Main Authors: Takahashi, K., Hokkaido Univ., Sapporo (Japan), Yoshioka, Y, Kato, E, Katsuki, S, Iida, O, Hosokawa, K, Kawabata, J
• Format: Article
• Language: English
• Subjects: ALFA GLUCOSIDASA; ALIMENT SANTE POUR HOMME; ALIMENTOS SANOS; ALPHA GLUCOSIDASE; Animals; Biological and medical sciences; Caffeic Acids; CHROMATOGRAPHIE EN COLONNE; COLUMN CHROMATOGRAPHY; CROMATOGRAFIA DE COLUMNA; DIABETE; DIABETES; Enzyme Assays; Enzyme Inhibitors - chemistry; Enzyme Inhibitors - pharmacology; ESPECTROSCOPIA RMN; Fruit - enzymology; Fundamental and applied biological sciences. Psychology; Glycoside Hydrolase Inhibitors; HEALTH FOODS; HIPERGLUCEMIA; http://www.fao.org/aos/agrovoc#c_10361; http://www.fao.org/aos/agrovoc#c_24395; http://www.fao.org/aos/agrovoc#c_24405; http://www.fao.org/aos/agrovoc#c_25396; http://www.fao.org/aos/agrovoc#c_29489; http://www.fao.org/aos/agrovoc#c_3760; http://www.fao.org/aos/agrovoc#c_7216; HYPERGLYCAEMIA; HYPERGLYCEMIE; Hypoglycemic Agents - antagonists & inhibitors; Hypoglycemic Agents - pharmacology; Intestines - drug effects; Japan; methyl caffeate; NMR SPECTROSCOPY; Rats; SOLANUM; Solanum - enzymology; Solanum torvum; SPECTROSCOPIE RMN; Sucrase - antagonists & inhibitors; Tanegashima; α-glucosidase inhibitor
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.90789

In screening experiments for rat intestinal α-glucosidase (sucrase and maltase) inhibitors in 325 plants cultivated in Japan's southern island, of Tanegashima, marked inhibition against both sucrase and maltase was found in the extract of the fruit of Solanum torvum. Enzyme-assay guided fractionation of the extract led to the isolation of methyl caffeate (1) as a rat intestinal sucrase and maltase inhibitor. We examined 13 caffeoyl derivatives for sucrase- and maltase-inhibitory activities. The results showed that methyl caffeate (1) had a most favorable structure for both sucrase and maltase inhibition, except for a higher activity of methyl 3,4,5-trihydroxycinnamate (14) against sucrase. Its moderate inhibitory action against α-glucosidase provides a prospect for antidiabetic usage of S. torvum fruit.