Hypoglycemic Potential of Triterpenes from Alstonia scholaris

Abstract

A dichloromethane extract of air-dry leaves of Alstonia scholaris (L.) R. Br. contains a mixture of cycloeucalenol (1a), cycloartanol (1b) and lupeol (1c); lupeol acetate (2); and betulin (3). The structures of these triterpenes were elucidated by extensive 1D and 2D NMR spectroscopy and confirmed by comparison of their 13 C NMR data to those reported in the literature. A previous study reported that the powdered leaves of Alstonia scholaris produced a highly significant decrease in blood glucose and a mechanism of this action was upon insulin triggering and direct insulin-like effects. Betulin and lupeol acetate were reported to exhibit hypoglycemic activity. Thus, only a mixture of 1a -1c was tested for hypoglycemic potential using the oral glucose tolerance test (OGTT). A possible hypoglycemic activity was observed for a mixture of 1a -1c at a dose of 25 mg/kg BW administered orally to normoglycemic mice.

Triterpenes From Ceriops Decandra (Griff.) W. Theob.

“…The NMR spectra of 1 are in accordance with data reported in the literature for 3β-E-coumaroylbetulinic acid (1) [17]; 2 for lupeol fatty acid esters [18], 3 for betulonic acid [19], 4 for betulin [20], 5 for betulinic acid [21], 6 for lupeol [16], 7 for lupenone [22], 8 for 3β-E-feruloyllupeol [2], 9 for 3β-Zferuloyllupeol [2], and 10 for chlorophyll a [23].…”