Isolation and Identification of Inhibitory Compounds from Morus alba cv. Chengmoknosang α-amylase and α-glucosidase

Jung-Woo Chae1, Hye-Jin Park2, Sun-Ae Kang2, Ju-Yeong Lee2, Bong-Jeun An3, Myung-Uk Kim4 and Yong-Je Cho5*

1Gyeonggi-Do Forest Environment Research Institute, Osan 447-290, Korea, 2School of Applied Bioscience, Kyungpook National University, Daegu 702-701, Korea 3Department of Cosmeceutical, Daegu Hanny University, Gyeongsan, 712-715, Korea 4Gyeongbuk Institute for Marine Bio-Industry, Uljin 767-813, Korea 5School of Food science & Biotechnology / Food & Bio-Industry Research Institute, Kyungpook National University, Daegu 702-701, Korea.

The objective of this research was to evaluate the inhibitory activities of phenolic compounds isolated from Morusalbacv.Kuksangagainstα-amylase and α-glucosidase. The total phenolics content of extracts from Morusalbacv.Kuksangwas 9.7±0.2 mg/g soluble in water and 14.3±0.2 mg/g soluble in ethanol. The inhibitory activity of the water extracts (200 μg/mL phenolics) against α-amylase and α-glucosidase was determined as 93.8% and 48.7% respectively. The purification of inhibitory compounds was carried out by Sephadex LH-20 and MCI-gel CHP-20 column chromatography using a gradient elution procedure of increasing ethanol in H2O. The quercetin was confirmed to be the chemical structure of the inhibitory compound agains α-amylase and α-glucosidase by spectroscopic analysis of FAB-MS, NMR and IR spectrum.