Hypoglycaemic effect of Momordica charantia extracts.
The hypoglycaemic effect of orally administered extracts of fruits of cultivated Momordica charantia (karela) was examined in normal and streptozotocin diabetic mice. In normal mice, an aqueous extract (A) lowered the glycaemic response to both oral and intraperitoneal glucose, without altering the insulin response. This aqueous extract (A) and the residue after alkaline chloroform extraction (B) reduced the hyperglycaemia in diabetic mice at 1 hour. Material recovered by acid water wash of the chloroform extract remaining after an alkaline water wash (D) produced a more slowly generated hypoglycaemic effect. The results suggest that orally administered karela extracts lower glucose concentrations independently of intestinal glucose absorption and involve an extrapancreatic effect. Two types of hypoglycaemic substances with different time dependent effects are indicated.