This study evaluated the antioxidant activity as well as bioflavonoid content of the methanol and ethanol-water extracts of the fresh and dried leaves of Tetracarpidium conophorum. Antioxidant activity was determined by spectrophotometric methods using DPPH free radical, nitric oxide radical inhibition and ferric reducing antioxidant power assays. In addition, total phenolics, flavonoids and proanthocyanidin content were also determined. The ethanol: water extract of the dried leaves had the highest antioxidant activity with a 50% inhibition of DPPH at a concentration of 0.017？mg/mL compared to the standards, Vitamin C and Vitamin E with inhibition of 0.019 and 0.011？mg/mL, respectively. This extract also showed nitric oxide radical inhibition activity comparable to that of rutin, 54.45% and 55.03% for extract and rutin, respectively, at 0.1？mg/mL. Ferric reducing power was also comparable to that of ascorbic acid (281 and 287？μM Fe (11)/g, resp.) at a concentration of 1？mg/mL. The methanol extract of both the dried and the fresh leaves had higher phenolic, flavonoids and proanthocyanidin content than the ethanol？:？water extract. The study reveals that T. conophorum can be an interesting source of antioxidants with their potential use in different fields namely food, cosmetics and pharmaceuticals. 1. Introduction Significant scientific evidence has shown that, under situations of oxidative stress, reactive oxygen species (ROS) such as superoxide, hydroxyl and peroxyl radicals are generated, and the balance between antioxidation (reduction) and oxidation is believed to be a critical concept for maintaining a healthy biological system [1]. These ROS play an important role in the etiology and pathophysiology of human aging [2] and diseases such as cancer [3], coronary heart disease [4], Alzheimer’s disease [5] and other neurodegenerative disorders [6], atherosclerosis [7], cataracts [8], and inflammation [9, 10]. Naturally there is a dynamic balance between the amount of free radicals produced in the body and antioxidants to scavenge or quench them to protect the body against deleterious effects. The amount of antioxidant principles present under normal physiological conditions may be insufficient to neutralize free radicals generated under pathological conditions. Therefore, it is important to enrich our diet with antioxidants to protect against harmful diseases. Hence, there has been an increased interest in the food industry and in preventive medicine in the development of “Natural antioxidants” from plant materials. The plant Tetracarpidium conophorum
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