In vitro antioxidant activity, phytochemical screening, cytotoxicity and total phenolic content in extracts of Caesalpinia pulcherrima (Caesalpiniaceae) pods

Abstract

Caesalpinia pulcherrima L. Swartz (Caesalpiniaceae) is an ornamental plant also used as a common medicinal plant in India, Taiwan and South-East Asian countries. Majority of the diseases/disorders are mainly linked to oxidative stress due to free radicals. The aims of this study were to screen for phytochemical constituents, evaluate cytotoxicity, in vitro antioxidant activity and estimation of total phenolic content of extracts of pods of Caesalpinia pulcherrima. Phytochemical analysis revealed the presence of tannins, flavonoids, steroids and alkaloids. Brine Shrimp Lethality (BSL) bioassay was used to investigate the cytotoxic effects. The LC 50,(μg mL-1) values obtained for extracts as 750 μ mL-1 for petroleum ether extract, 800 μL-1 for chloroform extract and 900 μL-1 for methanol extract. The total phenolic content of the methanolic extract was 38.04% w/w, equivalent to gallic acid. Petroleum ether, chloroform and methanolic extracts of Caesalpinia pulcherrima and standard ascorbic acid were found to be scavenger of DPPH radical with an IC50, of 124.75, 112.08, 54.34 and 13.86 μg mL-1, respectively. Methanolic extract was good scavenger of DPPH radical. Petroleum ether, chloroform, ethyl acetate soluble fraction of methanolic extracts of pods of Caesalpinia pulcherrima and ascorbic acid were found to be scavenger of nitric oxide radical with an IC50 of 93.32, 65.12, 54.83 and 12.59 μL-1, respectively. Ethyl acetate soluble fraction was found to be good scavenger of nitric oxide radical. Our conclusion provides support that the crude extracts of C. pulcherrima is a probable source of natural antioxidants and this justified its uses in folkloric medicines. © 2012 Asian Network for Scientific Information.