Abstract:
Garcinia cowa has risen the interest of scientists and researchers since some of the active
constituents and phytochemicals found on this plant are known to exert many beneficial effects.
Garcinia is a rich source of secondary metabolites.
Phytochemical investigations of the plant parts indicated that leaves are the best source of
secondary metabolites, providing glycosides, alkaloids and xanthones respectively. Many of the
isolated compounds have a wide range of pharmacological activities including anticancer, antiinflammatory,
antibacterial, anti-fungal, antidepressant and antioxidant.
The aim of the present study was to evaluate the antioxidant and antimicrobial activity of
petroleum ether ( pet ether ) extract of Garcinia cowa. The antioxidant activity was measured by DPPH and total Phenol test. The IC50 values of DPPH
test was 242.188μg/ml for pet ether extract of Garcinia cowa leaves. The Total Phenol content
was 107.47±30.62 mg/g equivalent to Gallic Acid for pet ether extract of Garcinia cowa leaves. The antimicrobial activities of pet ether extract of Garcinia cowa leaves were tested against ten
microorganisms by observing the zone of inhibition. The antimicrobial test was performed by
disc diffusion method.In case of 300 g/disc, the highest antimicrobial activity was shown
against Pseudomonas aureus. The diameter of the zone of inhibition was 12mm compared to the
30 mm of diameter of the zone of inhibition of the standard zentamycin. It showed the moderate
activity against Bacillus subtilis, Salmonella paratyphi, Salmonella typhi, Shigella dysenteriae,
Vibrio parahemolyticus, Staphylococcus aureus and Escherichia coli. In case of 600 g/disc, the
highest antimicrobial activity was shown against Bacillus megaterium and Sarcina lutea. The
diameter of the zone of inhibition was 12mm compared to the 30 mm of diameter of the zone of
inhibition of the standard Gentamycin. In conclusion, further investigations are needed to identify the active constituents and the exact
mechanism(s) of action responsible for the reported antimicrobial and antioxidant properties of
Garcinia cowa.
Description:
This thesis submitted in partial fulfillment of the requirements for the degree of Bachelor of Pharmacy (B.Pharm) in East West University, Dhaka, Bangladesh.