Studies on Antioxidant Activity, Total Phenolic and Total Flavonoid Contents of Terminalia Catappa Leaves Using In-vitro Models

Plants produce a diverse range of bioactive molecules, making them a rich source of different types of medicines. A regular and widespread use of herbs throughout the world has increased serious concern over their quality, safety and efficacy. Thus, a proper scientific evidence or assessment has become the criteria for acceptance of herbal health claims. In the present study, we examined the antioxidant effects of Terminalia Catappa plant extract. Dried and powered of T. Catappa was extracted with hexane, chloroform, methanol, ethanol and water. Total phenolic and flavonoid contents of different solvent extracts were determined. Of the different solvent extracts, methanol extract had the highest phenol and flavonoid content of 121.9±3.1mg/g and 59.6±1.5mg/g respectively. Antioxidant assays were carried out by using different in vitro models such as total reducing power, total antioxidant activity, lipid peroxidation inhibitory activity, DPPH radical scavenging activity and superoxide radical scavenging activity. methanol extract showed the highest total antioxidant activity of 41.4±0.45 µM Fe(II)/g. The EC50 values of ethanol extract for lipid peroxidation inhibitory activity and DPPH radical scavenging activity was found to be 0.1 and 0.5 mg/ml respectively. The anti-oxidant activities of other solvent extracts were poor when compared to the ethanol extract. These results suggest that, the active antioxidant compounds are better extracted in ethanol and there is a direct correlation between the total polyphenols extracted and its anti-oxidant activity. The invitro anti-oxidant activity of T. Catappa justifies the ethno medical use of this plant.