The crude extract of Aconitum napellus Linn. (Ranunculaceae) was obtained to evaluate their acute toxicity, pharmacological and biological effects. The pharmacological activities (acute toxicity study, neuropharmacological, analgesic and anti-inflammatory activities) were performed on mice at different doses whereas biological study was carried by immunomodulatory, antimicrobial, antimicrobial, phytotoxcity and antioxidant assays. The results of acute toxicity study revealed nontoxic behavior at 1-10 mg/kg dose while at 300mg/kg toxic symptoms appeared. A. napellus decreased the motor activity and exploratory behaviour and increased traction time at the dose of 10 mg/kg. The results of analgesic and anti-inflammatory activities were significantly reduced the number of writhes and edema at p<0.05 at 10 mg/kg which.  At 15.60 mg/ml, the results of immunomodulatory assay showed maximum phagocytic index. Among antibacterial results the best activity was achieved against Acineto bacterbaumanii (21 mm zone of inhibition). FTIR, HPLC analysis and antioxidant studies were also carried out. The highest anti-oxidant values achieved with A. napellus were 98%, 92% and 78% at the concentrations of 0.5mg/ml, 1mg/ml and 5mg/ml respectively. FTIR and HPLC were also performed to standardize the extract. These findings may help to establish the useful medicinal and therapeutic application of A. napellus.

Keywords: A. napellus,  toxicity study, pharmacological activity, Antioxidant, biological assays