Antioxidant Activity in Piper Betel and Nicotiania Tabaum

The aqueous extract of Piper betel L. and Nicotiania tabaum were studied for antioxidant activity on different in vitro models namely 1, 1-diphenyl, 2-picryl hydrazyl (DPPH) assay, nitric oxide assay and trichloroacetic acid based reducing power method. Ascorbic acid was also evaluated for comparison. The extracts showed free radical scavenging property in the tested models. Piper betel L. showed 98.06% inhibition of DPPH at 1000 μg and its activity at 500 μg (i.e. 94.35%)was comparable to that of ascorbic acid at 30μg (93.58%). While the maximum percentage inhibition by Piper betel L. and Nicotiania tabaum in the nitric oxide model was found to be only 62.14% and 33.36%, respectively, the activity of 1024 μg of Nicotiania tabaum and 128μg of Piper betel L. of compares favorably with that of 30 μg ascorbic acid. Piper betel L. showed high reductive ability. This study demonstrates the higher anti oxidant activity is present in the leaves of Piper betel L. when compared to Nicotiania tabaum.