Pharmacognostic, Phytochemical Evaluation and Antioxidant Activity of Onosma Bracteatum

Abstract

The aim of study is to isolate and quantify compound and evaluation of Phytochemical & antioxidant potential of extract and fractions of leaves of O. bracteatum. The information obtained from preliminary phytochemical screening will be useful in finding out the genuine of the drug. The result of phytochemical screening of powder drug, alcohol, aqueous extract of Onosma bracteatum leaf are presented in the phytochemical screening indicated varying quality of alkaloids, carbohydrate, glycoside, sterol, saponins, protein, mucilage, terpenoid, flavonoid, phenol, protein and amino acids in the leaf extract. The phytochemical profile revealed that the methanolic and ethanolic extract contained aldehydes, carbohydrate, glycoside, sterol, saponins, protein, mucilage, tannins, terpenoids and phenols. The antioxidant activities of different extracts were indexed by the DPPH radical scavenging activity.Different extracts possessed varying free radical scavenging activities. Among the extracts tested, methanolic extract was the most potent extract with an IC50 value of 21.76 µg/mL with percentage inhibition of 85.46. Compared to methanolic extract, although ethyl acetate and ethanolic extract exhibited a lower radical scavenging activity with respective IC50 values of 28.31 µg/mL and 33.49 µg/mL with percentage inhibition of 76.37 and 64.75 respectively. IC50 value of methanolic extracts had significantly the same radical scavenging activity as that of ascorbic acid (IC50¬18.21 µg/mL).