ABSTRACT
Objective: To evaluate the antidiabetic and the antidiarrhoeal effects of ethanolic extracts of Psidium guajava leave (EEPGL) in Wister rats to support its traditional uses. Methods: Oral glucose tolerance test model and alloxan induced diabetic test model were performed to evaluate antidiabetic activity of EEPGL at doses of 1.00, 0.50 and 0.75 g/kg respectively. For antidiarrhoeal effects of EEPGL, castor oil-induced diarrhoea model and gastrointestinal motility test with barium sulphate milk model were also assessed at doses of 750, 500 and 250 mg/kg, respectively. Results: Administration of EEPGL at doses 1.00 and 0.50 g/kg significantly (P<0.05) decreased blood glucose levels in oral glucose tolerance test model as well as 0.75 g/kg dose in alloxan induced diabetic test model in Wister rats (P<0.001). Application of EEPGL at doses of 750 and 500 mg/kg showed antidiarrhoeal effect in castor oil-induced diarrhoeal model (P<0.001 and P<0.01, respectively), and 750 mg/kg (P<0.01), 500 and 250 mg/kg (P<0.05) doses in barium sulphate milk model in aforesaid animals. Conclusions: These results exhibited the significant antidiabetic and antidiarrhoeal activities of ethanolic extracts of Psidium guajava leave in Wister rats
ABSTRACT
Blighia sapida is a medicinal plant used in Southern Nigeria for the treatment of some eye ailments and headache. The Centre for Scientific Research into Plant Medicine (CSRPM), Ghana, has used this plant for the treatment of diarrhea for over 20 years. Objective: This study was designed to investigate the lethal effect of aqueous, ethanol, and ethyl acetate extracts of the leaf of B. sapida on fourth instar larvae of An. gambiae, Cu. quinquefasciatus and Ae. aegypti. Methods: The lethal effect of aqueous, ethanol and ethyl acetate extracts of the leaves of B. sapida at concentrations of 0.15, 0.30, 0.45, 0.60 and 0.75% w/v each were investigated in static bioassays on 4th 15 instar larvae of An. gambiae, Cu. quinquefasciatus and Ae. aegypti. Results: The 72hLC50 values of the aqueous extract were 0.393, 0.488 and 0.423%w/v for larvae of An. gambiae, Cu. quinquefasciatus and Ae. aegypti respectively, while the values for the ethanol extract were 0.319, 0.407 and 0.384%w/v for An. gambiae, Cu. quinefasciatus and Ae. aegypti larvae respectively. For the ethyl acetate extract tested against larvae of An. gambiae, Cu. quinquefasciatus and Ae. agypti, the 72hLC50 values were 0.135, 0.177 and 0.133% w/v respectively. As judged by the 72hLC50 values ethyl acetate extract was the most potent of the three extracts. Conclusions: Results obtained demonstrate that the leaves of B. sapida have marked larvicidal potential against mosquito larvae used in this study.