Phenolic Content, Reducing Power and Membrane Protective Activities of Solanum xanthocarpum Root Extracts

Present study reports the reducing and lipo-protective activities of phytoconstituents present in S. xanthocarpum root. The phytochemicals were sequentially extracted with the solvents with increasing polarity. Differential amount of total phenolic contents was present in various root extracts. Polar fractions accounted for higher phenolics contents. Ethyl alcohol (ET) extract exhibited maximum phenolics content (101.78 +/-0.41 mg catechol equivalent/g) followed by ethyl acetate (EA) and aqueous (AQ) extracts (59.55 +/-0.25 and 45.32 +/-0.33 mg CE/g, respectively). Reducing power and lipo-protective activities were assessed for the determination of antioxidant capacity. Lipo-protective activity was determined by lipid peroxidation inhibition (LPOI) assays in tissue (rat kidney) homogenate. ET, AQ and HX (hexane) fractions demonstrated considerable reducing power at different test concentrations exhibiting dose dependent response in the range 250-1000 mu g/ml. Some of the polar extracts produced about 50% protection against lipid peroxidation. Analysis of the data showed positive correlation of reducing power with total phenolic content (r(2)=0.322) and % LPOI (r(2)=0.317). The relationship between total phenolics content and % LPOI was also found to be positive (r(2)=0.539)..