In vitro Antioxidant, Antimicrobial and in vivo Peripheral Analgesic Activities of Methanol and Petroleum Ether Extracts of Whole Plant of Uraria lagopoides DC

Aims: To study and evaluate in vitro antioxidant, antimicrobial and in vivo peripheral analgesic activities of both methanol and petroleum ether extracts of whole plant of Uraria lagopoides DC (Family-Fabaceae).

Study Design: Preliminary phytochemical screening, evaluation of antioxidant, antimicrobial and peripheral analgesic activities.

Place and Duration of Study: Department of Pharmacy, Jahangirnagar University, Savar, Dhaka-1342 and Department of Pharmacy, Primeasia University, Dhaka-1213. The studies were carried out during February- September 2013.

Methodology: Phytochemical constituents were identified by qualitative analysis. In vitro antioxidant activity of the extracts were studied using DPPH radical scavenging assay, total phenol, total flavonoid content and total antioxidant capacity determination assays. Antimicrobial activity was investigated by disc diffusion technique and acetic acid induced writhing test was used for the evaluation of in vivo peripheral analgesic activity of the whole plant extracts.

Results: Phytochemical screening for both extracts showed positive results for carbohydrates, flavonoids and glycosides while only methanol extract showed positive results for alkaloids, saponins, steroids and tannins. Methanol extract of the plant showed higher total phenolic content and as well as higher DPPH free radical scavenging activity than petroleum ether extract. On the other hand, petroleum ether extract showed higher total flavonoid content and total antioxidant capacity than methanol extract. In disc diffusion technique among six bacterial species, methanol extract showed concentration dependent activity against one Gram positive (Staphylococcus aureus) and three Gram negative bacteria (Escherichia coli, Salmonella typhi and Klebsiella pneumoniae) while petroleum ether extract showed concentration dependent activity against only one Gram negative bacteria (Salmonella typhi). In acetic acid induced writhing test both methanol and petroleum ether extracts of 250 mg/kg and 500 mg/kg (per oral) both doses showed significant (P < 0.001) analgesic activity.