Department of Pharmacy,
Southeast University, Banani, Dhaka, Bangladesh
Garuga pinnata (family: Burseraceae) has many traditional medicinal uses including as astringent, bronchodilator, stomachic, expectorant, pulmonary infection, antidiabetic etc. The present study is based on this plant to evaluate the antimicrobial, antioxidant and cytotoxic properties of G. pinnata leaves. Antimicrobial activity of chloroform extract was evaluated against four Gram positive bacteria Bacillus megaterium, Bacillus subtilis, Sarcina lutea, Staphylococcus aureus and five Gram negative bacteria Escherichia coli, Pseudomonas aeruginosa, Salmonella paratyphi, Shigella dysentriae, Vibrio mimicus, and two common fungus Aspergillus niger, Candida albicans by applying disc diffusion method where Kanamycin disc (30 µg/disc) was used as reference standard. The chloroform extract of G. pinnata leaves showed very good antimicrobial activity against both gram positive and gram negative bacteria and fungus A. niger. The most susceptible microorganism was S. paratyphi (19 mm zone of inhibition) followed by B. subtilis (15 mm zone of inhibition). The antioxidant activity of chloroform extract of G. pinnata leaves was evaluated spectrophotometrically using 1,1-diphenyl-2-picrylhydrazyl (DPPH) for radical scavenging and ascorbic acid was used as standard. The extract exhibited strong DPPH radical scavenging activity with IC50 value of 57.06 µg/ml as compared to the IC50 value of the reference standard, ascorbic acid (37.21 µg/ml). The cytotoxic activity of G. pinnata was determined by brine shrimp lethality bioassay using vincristine sulfate as standard. The chloroform extract revealed significant cytotoxic activity with LC50 of 6.607 µg/ml whereas LC50 of Vincristine sulphate was 6.026 µg/ml.