%0 Journal Article %T Oleanolic acid - an &alpha -Glucosidase inhibitory and antihyperglycemic active compound from the fruits of Sonneratia caseolaris %A Ashok Kumar Tiwari %A V. Viswanadh %A Ponnapalli Mangala Gowri %A Amtul Zehra Ali %J Open Access Journal of Medicinal and Aromatic Plants %D 2010 %I Medicinal and Aromatic Plants Association of India %X Fruits of Sonneratia caseolaris Linn. have many therapeutic applications in folklore medicine. However, chemical examination and biological activity of its fruit are less studied. During the work on identification of antidiabetic principles from Indian mangrove flora, we noticed moderate intestinal ? -glucosidase inhibitory activity of the methanolic extract of its fruits. Three compounds namely oleanolic acid, ? -sistosterol- ? -D-glucopyranoside and luteolin were isolated and identified from the bioactive methanolic extract. In vitro pre-incubation of crude rat intestinal ? -glucosidase with oleanolic acid showed potent ? -glucosidase inhibitory (IC50 = 15 ? M) activity, however, its inhibitory potential decreased drastically when oleanolic acid was pre-incubated with substrate. In in vivo studies also, pretreatment of rats with oleanolic acid displayed significant (p<0.05) antihyperglycemic activity in starch tolerance test however, administration of starch fortified with oleanolic acid to the rats could not exhibit antihyperglycemic activity. This is the first report identifying oleanolic acid in S. caseolaris fruits in substantial yield and assigning its intestinal ?-glucosidase inhibitory and antihyperglycemic activities. This study also highlights the fact that the mode of incubation in in vitro experiments and administration of active principles isolated from natural medicinal plants in in vivo studies play important role in revealing various facets of their biological activities and therapeutic implications. %K Antidiabetic activity %K crabapple %K mangroves %K oleanolic acid %U http://epubs.icar.org.in/ejournal/index.php/JMAP/article/view/4376