Antioxidant and antimutagenic activity of Curcuma caesia Roxb. rhizome extracts

The rhizomes of Curcuma caesia Roxb. (zingiberacea) are traditionally used in treatment of various ailments and metabolic disorders like leukoderma, asthma, tumours, piles, bronchitis, etc. in Indian system of medicine. Considering the importance of natural products in modern phytomedicine, the antioxidant and antimutagenic activities of C. caesia Roxb. rhizome extract and its fractions were evaluated. The ethanolic fraction showed highest antioxidant activity by DPPH assay (86.91%) comparable to ascorbic acid (94.77%) with IC50 value of 418 μg/ml for EECC followed by MECC (441.90 μg/ml) > EAECC(561 μg/ml) > AECC(591 μg/ml). Based on the antioxidant activity, three of the rhizome extracts were evaluated for their antimutagenic properties against indirect acting mutagen cyclophosphamide (CP) using Salmonella typhimurium strains TA98 and TA100. The antimutagenic activity of the extracts against indirect acting mutagen cyclophosphamide in the presence of mammalian metabolic activation system was found to be significant (p < 0.01, p < 0.05). All the extracts showed similar antimutagenicity in dose dependent manner. The total phenolic content as well as reducing ability of the extracts was also determined.