Antioxidant, Anti-Inflammatory and Antibacterial Activities of Leaves of Garcinia Zeylanica

Plants are being used to treat many diseases despite the development of synthetic drugs due to their low side effects. This study involves the determination of the antioxidant, anti-inflammatory, and antibacterial activity of Garcinia zeylanica leaves. Aqueous leaf extract of Sri Lankan variety of Garcinia zeylanica (Kaha goraka/Ela goraka), prepared according to the method of “Kasaya” (ALEGZ) in Ayurvedic medicine was used for this study. ALEGZ gave a Total Phenolic Content of 696.1 mg (PGE) g-1 in Folin-Ciocalteu assay and Total Flavonoid Content of 214.9 mg (QE) g-1 in AlCl3 colorimetric assay. The 2, 2- diphenyl-1-picrylhydrazyl radical scavenging activity of ALEGZ (0.10-4.00 mg/ml) ranged between 28.4%-80.7% whereas for ascorbic acid the percentage was 40.5%-87.1% at the same concentration range. The ALEGZ also showed a considerable amount of ferric ion reducing ability at the concentration range of 0.25-5.00 mg/ml. Hydroxyl radical scavenging activity of the ALEGZ (0.5-5.0 mg/ml) was 21.3%-59.4% and ascorbic acid showed 69.7%- 84.3% activity. In the anti-inflammatory assay, ALEGZ (20-70 µg/ml) gave nitric oxide scavenging activity of 9.7%-63.6% whereas for ascorbic acid it was 28.0%-72.7%. Human red blood cell membrane assay showed a protection of 18.7%-60.8% for the ALEGZ (100-1000 µg/ml) and aspirin showed its protection between 19.1%-65.4%. The ALEGZ also showed antibacterial activity against Staphylococcus aureus and Bacillus subtilis. According to these results, the ALEGZ has proved that it has the ability to combat diseases in which radicals are implicated as well as inflammation and bacterial infestation by Bacillus subtilis and Staphylococcus aureus.