SYNERGISTIC ACTION OF PHYTOCHEMICALS AUGMENTS THEIR ANTIOXIDATIVE EFFICACY: AN IN VITRO COMPARATIVE STUDY

摘要

Objective: The present study was aimed to find out the comparative in vitro antioxidative activity of three commercially available polyherbal formulations (PHFs) and Gymnema sylvestre, the major constituent of all the test formulations. Methods: Different in - vitro free radical scavenging assays such as 1, 1-Diphenyl-2-picrylhydrazyl (DPPH), Nitric oxide (NO), reducing power assay and ferrous sulphate (FeSO 4 ) induced lipid peroxidation (LPO) in liver and kidney homogenates were performed in four parallel sets for each drug. Total polyphenols and flavonoid contents were also estimated. Results: Although all the test drugs exhibited significant free radical scavenging activity, Madhuhari was found to be the most effective one against DPPH, NO and FeSO 4 induced free radical systems. However, their higher concentrations were peroxidative in nature. Conclusion: Poly herbal formulations were more antiperoxidative as compared to mono herb preparation. As all the test drugs showed decreased efficacy and/or peroxidative effects at their higher concentrations, their higher dose should be avoided. Significant amount of polyphenols and flavonoids present in the test drugs supported their antioxidative property. This study appears to be the first one to demonstrate a comparative protective as well as harmful effect(s) at higher concentration of three herbal formulations.