ANTIOXIDANT AND ANTI-INFLAMMATORY ACTIVITIES OF THE LEAF EXTRACT OF BRASSICA NIGRA

Crude ethanolic extract of Brassica nigra was studied to detect the chemical compounds as well as to evaluate the antioxidant and anti-inflammatory activities. The different antioxidants assays including total antioxidant activity, DPPH, nitric oxide (NO) scavenging, reducing power, total phenolic content and flavonoid content were studied. Phytochemical screening showed the presence of alkaloids, flavonoids, glycosides and carbohydrates in the extract. Total phenol content in the plant was 6.67 mg/g of galic acid. Brassica nigra was found to contain 2.04 mg/g of quercetin in flavonoid assay. Total antioxidant capacity of the extractwas found to be 97.08 mg/g of ascorbic acid. Brassica nigra showed IC ₅₀ value of 63.09µg/ml whereas the standard antioxidant showed IC ₅₀ value 14.45 µg/ml in DPPH method. The standard antioxidants ascorbic acid, galic acid and quercetin showed the reducing power 485.75%, 736.30% and 763.01%, respectively whereas Brassica nigra showed the value 263.69%. IC₅₀ value in NO scavenging activity of the extract was found to be 118.21 µg/ml whereas ascorbic acid showed the value 5.47 µg/ml and quercetin had the value 15.24 µg/ml. In vivo and in vitro anti-inflammatory activity of the crude extract was evaluated using carrageenan induced rat paw edema and protease enzyme inhibition assay, respectively. In vivo anti-inflammatory test of the ethanolic extract of Brassica nigra (500 mg/kg) gave 17.9% inhibition whereas standard Phenylbutazone (100mg/kg) gave 39.38%. In vitro anti-inflammatory test of B. nigra by protease inhibition method also gave 42.57% inhibition of trypsin at dose 250 µg/ml.