Abstract

ANTIDIABETIC EFFECTS OF AQUEOUS AND 80% METHANOL EXTRACTS, AND SOLUBLE FROM CYMBOPOGON CITRATUS (DC.) STAPF (POACEAE) AND LIPPIA MULTIIFOLIA MOLDENKE (VERBENACEAE) LEAVES ON STREPTOZOCIN-INDUCED DIABETIC RATS

Musimbele N., Mpona M. M., Mondo M., Kikweta M. C. and Cimanga K. R.*

ABSTRACT

The present study was conducted to evaluate the hypoglycemic and antidiabetic activities of aqueous and methanol 80% extracts, soluble fractions chloroform, ethyacetate, n-butanol and residual aqueous, and crude polysaccharides from Cymbopogon citratus and Lippia multifolia leaves as well as the combined aqueous extracts and soluble fractions of the two plant parts, against diabetogenic product strepotozocin-induced diabetic rats. In hypoglycemic test, at the highest oral dose of 400 mg/kg body weight, aqueous and methanol 80% extracts and soluble fractions from both plants displayed significant reduction of glucose levels of treated rats from 80.0±0.3 to 84.3 ±0.5 mg/dl for C. citratus samples and from 80.0±0.3 to 84.0±0.3 mg/dl for L. multifolia samples after 5 h of all crude polysaccharide extracts PCc and PLm administered at highest oral dose of 200 mg/kg bw, reduced significantly glucose level of hypoglycemic treated rats In antidiabetic test for 5h, at the highest oral dose of 400 mg/kg body weight, aqueous and methanol 80%, soluble fractions and polysaccharides from C. citratus and L. multifolia caused significant decrease of glycemia levels of treated diabetic rats from 154.8±0.2 to 177.3±0.5 mg/dl for C. citratus samples and from 151.8±02 to 177.6±02 mg/dl for L. mulifolia samples after 5 h of observation. In antidiabetic test for 21 days of treatment, at the same oral dose, all samples from both medicinal plants caused significant reduction of gylcemia of treated rats to values from 87.3±0.2 to 93.6±0.1 mg/dl for C. citratus samples and from 85.2±0.2 to 113.2±0.1 mg/dl for L multifolia after 21 days of treatment. Both aqueous extracts showed also significant reduction of glucose of treated hyperglycemic rats in oral glucose tolerance test Moreover, a synergistic antidiabetic effects was observed with the combined aqueous extract of C. citratus and L. multifolia on antidiabetic activity of treated diabetic, at the highest dose of 400 mg/kg body weight producing glycemia decrease of treated diabetic rats to 110.6±0.4 mg/dg against 162.2±0.4 and 165.6 mg/dl produced by aqueous extract of C. citratus and L. multifolia tested alone in 5h, and this mixture showed 83.6±0.3 mg/dl against 86.5±0.1 and 86.8±0.5 mg/dl produced by aqueous extracts tested alone respectively for 21 days of treatment showing thus a synergistic effect.

Keywords: Cybompogon citratus, Poaceae, Lippia multifolia, Verbenaceae, leaves, aqueous and methanol 80% extracts, soluble fractions, hypoglycemic, antihyperglycemic and antidiabetic activity, synergistic effect.