Abstract
Context: Enicostema axillare A. Raynal (Gentianaceae) has been used in the traditional Indian system of medicine as a depurative and for the treatment of skin diseases, tumors, intermittent fever, and helminthiasis.
Objective: E. axillare was investigated for antimutagenic and antioxidant effects.
Materials and methods: The antioxidant and antimutagenic activities of E. axillare fractions were determined by 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging assay and Ames test using Salmonella typhimurium tester strains TA98 and TA100 against direct-acting mutagens, such as sodium azide (NaN
3
), 4-nitro-O-phenylene diamine (NPD), and mutagen needing activation, such as 2-aminofluorene (2AF). Toxicity study of these fractions was also performed.
Results and discussion: The ethyl acetate fraction showed maximum antimutagenic effect by 88.25 and 84.46% (preincubation) and 85.13 and 84.47% (coincubation) of inhibition against NaN
3
and NPD-induced mutagenicity, respectively. Inhibition of S9-dependent mutagens such as 2AF was higher than direct-acting mutagens by the ethyl acetate fraction of E. axillare. It showed 90.25 and 92.00% of inhibition in the preincubation and coincubation experiments. The ethyl acetate fraction showed higher total antioxidant capacity (24.79 ± 0.29 µg) and low IC
50
value for DPPH radical scavenging assay (192.27 ± 3.67 µg). The overall effect of E. axillare fractions was found to be in the order: ethyl acetate > methanol > hexane in these assays. In subacute toxicity study, with oral administration of these fractions, no marked biochemical and histopathologic changes were observed.
Conclusion: The significant antimutagenic and antioxidant activities of E. axillare might provide a scientific validation for the traditional use of this plant.