Antioxidant, analgesic and toxic potentiality of stephania japonica (Thunb.) miers. leaf

Abstract

In the present study crude methanolic extract of Stephania japonica leaf was investigated for possible antioxidant, analgesic and toxic activity. The extract showed antioxidant activity in DPPH radical scavenging activity, nitric oxide scavenging activity and reducing power assays. In both DPPH radical and NO scavenging assay, the extract exhibited moderate antioxidant activity and the IC50 values in DPPH radical scavenging and NO scavenging assays were found to be 105.55±1.06 and 129.12±0.15 ug mL-1, respectively while the IC50 values of ascorbic acid were 12.30±0.11 and 18.64±0.22 ug mL-1, respectively. Reducing power activity of the extract increased in a dose dependent manner. Analgesic activity of the crude extract was evaluated using acetic acid-induced writhing model of pain in mice. The crude extract at 200 and 400 mg kg-1 b. wt. doses displayed significant (p<0.001) reduction in acetic acid induced writhing in mice with a maximum effect of 75.89% reduction at 400 mg kg-1 b.wt. which is comparable to the standard, diclofenac sodium (86.52%). The extract was also investigated for toxic potentiality using Brine Shrimp lethality bioassay. In this bioassay the extract showed significant toxicity to Brine Shrimp nauplii with the LC50 value of 25.19±0.98 ug mL-1. The study clearly indicates that the extract possesses good analgesic and cytotoxic activity along with moderate antioxidant potential.