The current research study has been carried out to explore the antioxidant activity and brine shrimp lethality bioassay of different fractions from the flower extract of Spilanthes acmella. Besides, this experiment was also assessed to find out the proximate analysis and phytochemical screening by following the perfect protocol. To fractionate by soxhletion using sequential extraction techniques powdered flower of the plant were treated with different solvents including n-hexane, chloroform, ethanol and water. For the evaluation of antioxidant activity, total antioxidant capacity determination, determination of total phenolic content and total Flvonoids contents by aluminium tricholoride method were used. In addition, ascorbic acid and gallic acid was used as a standard antioxidant compound in these studies. Concerning the proximate analysis, moisture content, total ash value, acid insoluble ash and water soluble ash value were found 8.6%, 3.76%, 3.30%, 3.20% respectively. To evaluate cytotoxicity, the brine shrimp lethality bioassay was used. For phytochemical screening different extract of those solvents were utilized that disclosed the presence of alkaloids, flavonoids, phenolic compounds, Tannins, amino acids on different fractions but the absence of reducing sugar and saponins. The results of all assay showed that all the extracts of Spilanthes acmella flower possess significant antioxidant activity. In brine shrimp lethality bioassay, ethanol extract of flower effect to brine shrimp nauplii and exhibiting highest toxicity having LC50 value 1.20 μg/ml as compared to standard dimethyl sulfoxide (LC50 1.31 µg/ml). These evaluations suggest that Spilanthes acmella flowers might be a better source of antioxidants and possess important cytotoxic effect.
