PHYTOCHEMICAL SCREENING AND IN VITRO ANTIOXIDANT POTENTIAL OF TRIBULUS TERRESTRIS FRUIT AND MESUA FERREA FLOWER EXTRACTS: A COMPARATIVE STUDY

摘要

Objective: This study aimed to investigate the antioxidants and free radicals scavenging properties of ethanolic extracts from Tribulus terrestris fruit (TTF) and Mesua ferrea flower (MFF). Methods: The antioxidant and free radical scavenging activities were measured by using standard protocols against phytoextracts used at 50, 100, 150, 200 and 250 μg/ml concentration. Total phenolic and flavonoid content were estimated using Folin-Ciocalteu and aluminium-chloride reagent assay methods. Results: Among the extracts, MFF showed the highest total antioxidant ability followed by TTF. With regard to various scavenging activities, MFF had the highest radical scavenging activity than TTF extract closely resembled the standards. Also, the reducing capacity on ferrous ion was high in MFF than TTF. The quantified phenolic contents of TTF and MFF ethanolic extracts were 27.0±0.36 and 57.0±0.32 mg gallic acid equivalent per gram extract respectively. A positive correlation (p value<0.001) was observed between phenolic content and free radical scavenging efficiencies. Conclusion: The results confirm that both MFF and TTF are important sources of natural antioxidants and serves as an effective free radical scavengers and/or inhibitors. Hence, both extracts are suitable plant-based pharmaceutical products can be used to handle 'free radical-mediated diseases.