Whole plant screenings for flavonoids and tannins contents in castor plant (Ricinus communis L.) and evaluation of their biological activities.

Abstract

Castor plant (Ricinus communis L.) extracts have been used by many natives of the world in treatment of several ailments. However actual phytochemicals that confer these cures are mostly unidentified since crude extracts are employed. This study evaluated the distribution and biological activities of flavonoids and tannins in various parts of Castor plant. Flavonoids and tannins were found quantitatively in leaves, stems, seeds and roots, while capsules only contain flavonoids. High antioxidant and antihemolytic activities were shown by some of flavonoids and tannins extracts such as comparable to ascorbic acid and butylated hydroxyl anisole, which were used as standard antioxidant and antihemolytic agents respectively. Remarkably inhibitory effects on the population proliferation of Streptococcus aureus and Krebsellia halize were observed at increasing concentrations (1 mg/ml, 5 mg/ml and 10 mg/ml) of flavonoids and tannins extracts. It thus implies that Castor plant possesses essential phytochemicals, which could be exploited for medicinal/pharmaceutical applications.