Adaptogenic and safety evaluation of seabuckthorn (Hippophae rhamnoides) leaf extract:: A dose dependent study

The effects of seabuckthorn (Hippophae rhamnoides L., Elaeagnaceae), leaf aqueous extract were examined in rats for its adaptogenic activity and toxicity. Dose dependent adaptogenic study of extract was carried out at different doses administered orally, 30 min prior to cold (5 degrees C)-hypoxia (428 mmHg)-restraint (C-H-R) exposure. After sub-acute toxicity studies on 10 and 20 times doses of maximal effective dose administered for 14 days (single oral dose of 1 g/kg and 2 g/kg once daily) and maximal effective dose administered for 30 days (single oral dose of 100 mg/kg once daily), biochemical and hematological parameters were studied in the serum and blood. The maximal effective adaptogenic dose of the extract was 100 mg/kg body weight. No significant changes were observed in organ weight/body weight ratios, of any vital organ studied (except liver and kidney in 1 g/kg and 2 g/kg body weight doses, respectively), and biochemical and hematological parameters of the sub-acute drug treated animals in comparison to control rats. In acute toxicity study LD50 of the extract was observed to be >10 g/kg when given orally. These results indicate that seabuckthorn leaf aqueous extract possess potent adaptogenic activity with no toxicity even after sub-acute (30 days) maximal effective dose administration. Crown Copyright (c) 2006 Published by Elsevier Ltd. All rights reserved.