Antioxidant, antibacterial activities and gc-ms analysis of methanol extract of buds of Hypericum hookerianum wight and arnott

Hypericum hookerianum belongs to the family Hypericaceae, is a perennial shrub which has southern and eastern Asia as its native. In India, it is found in higher altitudes of Nilgiris, Khasi and jaintia hills of Himalayas and Palani hills of Western Ghats. The plant is used as folk medicine in various parts of the world and is used to treat an antidepressant and antiviral activity. The study is performed for the antioxidant and antibacterial activities of buds of Hypericum hookerianum. DPPH radical scavenging, ABTS⁺ radical cation scavenging, Fe³⁺ reducing power and phosphomolybdenum reduction assays were carried out for antioxidant activity. GC-MS analysis was carried out for the detection of volatile and semi-volatile compounds. The buds showed DPPH radical inhibition of 86.16% at 120 μg/mL concentration and ABTS⁺ radical cation inhibition of 83.65% at 30 μg/mL concentration. The phosphomolybednum reduction and Fe³⁺ reduction assays were showed 95.94% and 91.78% reduction at 120μg/mL concentration of the extract. Also, this extract exhibited good antibacterial activity against Escherichia coli. GC-MS analysis showed the presence of flavones (2H-1-Benzopyran-4,7-diol, 3,4-dihydro-2-phenyl- and 4H-1-Benzopyran-4-one, 2-(3,4-dimethoxyphenyl)-7-hydroxy-) which are responsible for antioxidant activity of the extract.