Phytochemical constituent and antioxidant activity of extract from the leaves of Ocimum gratissimum

Abstract

Extracts from the leaves of Ocimum gratissimum were investigated for phytochemical constituent and antioxidant activity. Tests for tannins, steroids, terpenoids, flavonoids and cardiac glycosides were positive in both methanolic and aqueous extracts. The methanolic extract of O. gratissimum had a DPPH scavenging activity of 84.6% at 250 µg/ml and a reductive potential of 0.77 at 100 µg/ml. These values were comparable with those of gallic acid, 91.4% at 250 µg/ml and ascorbic acid, 0.79 at 60 µg/ml as standards for DPPH scavenging activity and reductive potential, respectively. These findings suggest that the rich phytochemical content of O. gratissimum and its good antioxidant activity may be responsible for its popular and wide traditional use.   Key words: Ocimum gratissimum, phytochemicals, antioxidant activity and reductive potential.