Alpha-glucosidase Inhibitory Activity of Traditional Malay Medicinal Plants Used for Treating Diabetes
Shaida Fariza Sulaiman, Ooi Kheng Leong
School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia.
Abstract
Many local plants are used in traditional Malay medicine to treat diabetes. The aim of this study was to screen 50 plant extracts used in traditional medicine to treat diabetes using a colorimetric alpha-glucosidase inhibitory microplate-based assay. Plant extracts were extracted using 80%methanol and the percentage of inhibitory activity of each extract at 10 mg/ml was determined. The leaf extract of Strobilanthus crispus exhibited the highest alpha-glucosidase inhibitory activity with 78.6% of inhibition. Seven other leaf extracts, namely, Andrographis paniculata, Cardiospermum halicacabum, Ficus deltoidea, Lagerstroemia speciosa, Orthosipon spicatus, Solanum melongena and Solanum nigrum showed more than 50% of inhibitory activity. To the best of our knowledge, this is the first comparative screening of alpha-glucosidase activity oftraditional Malay medicinal plants.
Keywords: Andrographis paniculata, Cardiospermum halicacabum, Ficus deltoidea, Lagerstroemia speciosa, Orthosipon spicatus, Solanum melongena and Solanum nigrum