Phytochemicals and Antioxidant Activity in the Floral Extracts of Bauhinia purpurea L. (Fabaceae)

Abstract

The present investigation deals with the phytochemical and evaluation of antioxidant activity in Bauhinia purpurea L. flower extracts.

The flowers of B. purpurea were collected during the month of October 2019. The collected flower sample was shade dried and powdered. The powdered sample was extracted with methanol, hexane and water according to the standard protocol. The phytochemical screening of extracts with various solvents revealed the presence of tannins, saponins, flavonoids, terpenoids and reducing sugars in it. The antioxidant activity was evaluated by the estimation of total phenolic content and radical scavenging activity. Folin-Ciocalteau (FC) method was used to determine the total phenolic content present in floral extracts of B. purpurea using Gallic acid as standard.

The aqueous extract of flowers recorded the highest total phenolic content of 249.56 µg GAE/g, while low contents were recorded in the methanol (29.02 µg GAE/g) and hexane extracts (8.26 µg GAE/g). DPPH method was employed here to measure the antioxidant activity. High percentage of radical scavenging activity was found in the aqueous extract (81.51%; IC₅₀=49.61 µg/ml) followed by methanol extract (29.10%; IC₅₀=167.5 µg/ml).

The flavonoid and terpenoids present in the flower extract suggests the antioxidant potential and justifies the therapeutic action which could be used as pharmaceutical agents.