Scientific validation of acute oral toxicity on albino wistar rats and evaluation of phytochemicals and antioxidant in Lobelia nicotianifolia Roth ex. Schult

Lobelia nicotianifolia is commonly known as wild tobacco, exhibits potential antiseptic, antimicrobial, antivenom, analgesic and antiepileptic properties and is traditionally used to treat various respiratory ailments. This study aimed to validate the phytochemicals, antioxidant potential, cytotoxicity and acute oral toxicity of the methanolic leaf extract of L. nicotianifolia (MLELN). Antioxidant potential of MLELN was evaluated by DPPH radical scavenging activity, cytotoxicity was assessed using the MTT assay on the NIH/3T3 cell line and albino Wistar rat was exposed for acute oral toxicity. Preliminary phytochemical screening revealed the presence of secondary metabolites, including alkaloids, phenolics, terpenoids, saponins, and steroids. MLELN has significant antioxidant properties (IC50 = 97.42 µg/mL). Cytotoxicity of MLELN on the NIH/3T3 cell line, yielding an IC50=343.58 µg/mL. Acute oral toxicity testing involved administering a single dose of MLELN at 2000 mg/kg body weight to Wistar albino rats, resulting in no mortalities or observable toxic effects. Hence, the LD50 (Lethal dose) value of MLELN was determined to be greater than 2000mg/kg body weight. Based on the results, it can be concluded that MLELN do not pose any toxic risk when given orally to Wistar albino rats.