Antioxidant and Free Radical Scavenging Activities of Newbouldia laevis Leaf extracts

Objectives: Oxidative stress is implicated in the etiology of life-threatening disease conditions. Newbouldia laevis (NL) have been used in folk medicine for stress related conditions, however, there is paucity of reports suggesting a connection between its efficacy and a possible antioxidant property. The aim of this study was to evaluate the antioxidant properties of NL leaf extracts. Methods: The methanol extract of NL was partitioned to obtain the chloroform fraction (CFNL) and the aqueous fraction (AFNL). Following standard laboratory procedures, the parameters were measured spectrophotometrically. Results: The MFNL recorded the highest activity for DPPH (76.4%), while all extracts only showed slight hydrogen peroxide scavenging capacity. Total antioxidant capacity at uniform concentration revealed an increasing order of activity from AFNL to MENL, correlating with total phenol contents which is in the same order. Furthermore, the extracts inhibited lipid peroxidation in a concentration dependent manner, with MENL recording the highest inhibition of 19.5%. The MENL however had the highest vitamin C concentration of 165.44mg/100ml. Conclusion: The above results not only demonstrate the antioxidant properties of NL, but suggests this as one of its possible mechanism of action and indicates the presence of potent principles with potential for application in stress related ailments.