Antioxidant and Antimicrobial Investigations of dichloromethane (DCM) Extract of Garcinia cowa Bark

Abstract

Many plants of the genus Garcinia (Family Clusiaceae) have been used in traditional medicine in several parts of the world for treatment of the most different illnesses. In Thailand, where twenty-nine species have been observed, G. mangostana, G. speciosa and G. cowa have been widely used in Thai folk medicine. The aim of the present study was to evaluate the antioxidant and antimicrobial activity of DCM extract of Garcinia cowa.The antioxidant activity was measured by DPPH scavenging assay and total phenol content.The IC50 values of DPPH scavenging assay was 69.903 μg/ml for DCM extract of Garcinia cowa bark. The total phenol content was 362.93±18 mg/g equivalent to gallic acid for DCM extract of Garcinia cowa bark. By determining antioxidant property the present result suggest that the tested plant extract have potent antioxidant activity. The anti microbial activity of DCM extract of Garcinia cowa plant were tested against ten microorganism by observing the zone of inhibition. The antimicrobial test was performed by disc diffusion method. The DCM extract of Garcinia cowa plant showed might ( (7mm-8mm) antimicrobial activities against the microorganism. The DCM extract of Garcinia cowa showed highest activity against vibrio parahemolyticus,Salmonella typhi,Bacillus sereus and moderate activity against Bacillus subitilis. No activity against was observed E.coli, Salmonella paratyphi, Staphylococcus aureus, pseudomonas aureus. Further investigations needed to identify the active constituents and the exact mechanism of action responsible for reported antioxidant and antimicrobial properties of Garcinia cowa.