FREE RADICAL QUENCHING EFFICACY OF VARIOUS EXTRACTS OF C.PICTUS TO COMBAT OXIDATIVE DAMAGE/STRESS: AN IN VITRO STUDY

Abstract

Objectives: The objectives of this research article are to elucidate the antioxidant activity of the sequentially extracted fractions using solvents with a varying range of polarity from the leaves of Costus pictus (Zingiberaceae). The antioxidant efficacy to combat the oxidative stress was evaluated based on their superoxide, hydrogen peroxide, and nitric oxide (NO) scavenging activity of the leaf extract.Methods: Extraction was performed by sequential extraction methods with low to high polar solvents. Using hexane as a low polar, dichloromethane as medium polar, and ethyl acetate and methanol as high polar, based on their individual boiling points extraction was carried out. The extracts were then evaporated using a rotary evaporator under vacuum and stored in the dry container. Then, antioxidant activity of each extract was evaluated for superoxide, hydrogen peroxide, and NO scavenging activity, ascorbic acid was used as a standard drug for the study of antioxidant activity. The output was statistically interpreted, and the most significant concentration of the best extract with good antioxidant activity was evaluated.Results: As the methanolic solvent is highly polar and able to retrieve the active lead components from the plant material, was very well correlated with the higher degree of free radical scavenging efficacy. It also exhibited the most and significant inhibition in superoxide radical scavenging, hydrogen peroxide scavenging, and NO scavenging which was about 86±1.23, 94±0.34, and 86±1.87 at 250 µg/ml of extract, respectively. The results from our experiments were in par with the positive control chosen.Conclusions: The above results help us to substantially conclude that bioactive components are extracted well in high polar solvents such as methanol, which mainly includes flavonoids and related polyphenols. These compounds present in C. pictus may be an active lead for potent antioxidant activities which would need further investigations in molecular level.Keywords: Costus pictus, Hexane, Dichloromethane, Ethyl acetate, Methanol, Ascorbic acid.