Orthosiphon stamineus, Benth, also known as Misai Kucing in Malaysia and Java tea in Indonesia, is traditionally used in Southeastern Asia to treat kidney dysfunctions, diabetes, gout and several other illnesses. Recent studies of Orthosiphon stamineus pharmacological profile have revealed antioxidant properties and other potentially useful biological activities thereby lending some scientific support to its use in folk medicine. So far the genotoxicity of Orthosiphon stamineus extracts has not been evaluated. In this study the genotoxic potential of Orthosiphon stamineus aqueous extract was investigated by the Salmonella/microsome mutation assay and the mouse bone marrow micronucleus test.
The present investigation was carried out to evaluate the safety of standardised 50% ethanol extract of Orthosiphon stamineus plant by determining its potential toxicity after acute and subchronic administration in rats.
The acute toxicity of standardized extract of Orthosiphon stamineus was studied in Sprague Dawley rats. The rats were administered a single dose of 5000 mg/kg body weight (BW) orally on Day 0 and observed for 14 days. There were no deaths recorded and the animals did not show signs of toxicity during the experimental period. The effect of the extract on general behavior, BW, food and water intake, relative organ weight per 100 g BW, hematology and clinical biochemistry were measured. All the parameters measured were unaffected as compared to the control. The acute toxicity LD(50) was estimated to be > 5000 mg/kg BW.
Orthosiphon stamineus Benth (Family: Lamiaceae) or locally known as Misai Kucing has been widely used in Malaysia for treating kidney problems, gout, and diabetes. This study aims to evaluate the possible toxic effect after following fourteen days oral administration of methanol extract of O. stamineus in female Sprague Dawley (SD) rats. Control groups were treated orally with distilled water (vehicle) while the four test groups were treated up to fourteen days with 0.5 g/kg, 1 g/kg, 3 g/kg and 5 g/kg body weight of methanol extract of O. stamineus respectively. Toxicity of the methanol extract of O. stamineus was evaluated by the incident of lethality, side-cage observation and blood serum biochemical parameters. No lethality or adverse toxic signs were seen during the experimental period. A significant decrease in several serum biochemical parameters i.e. AST and ALT and increase in liver weight was observed in young female SD rat after being fed fourteen days with methanol extract of O. stamineus. No delayed toxic effect and lethality was observed in all rats during fourteen days of recovery period. In conclusion, methanol extract of O. stamineus within these range and treatment duration would not cause any severe toxic effects and organ damages in rats.