Comparative studies of phytochemical contents and antioxidant potentials of selected nuts consumed in eastern part of Nigeria

Abstract

The study investigated and compared the phytochemical contents and antioxidant potentials of tiger nut, groundnut, cashew nut and walnut. Phytochemical contents and the antioxidant studies of the nut extracts were done following standard methods. The result of this study showed that the nut extracts had varied concentration of the phytochemical contents. The nut extracts scavenged DPPH with EC50 of (2.00 ± 0.00, 3.51 ± 0.01, 3.00 ± 0.01 and 2.00 ± 0.0 µg/ml) for tiger nut, groundnut, cashew nut and walnut respectively compared to ascorbic acid standard (1.25 ± 0.02 µg/ml). The extracts also reduced hydroxyl radical (OH-), EC50 (1.74 ± 001, 2.60 ± 0.01, 1.92 ± 0.01 and 1.48 ± 0.00 µg/ml) compared to ascorbic acid standard EC50 (1.14 µg/ml). Reduction of ferric ion to the ferrous form and the total antioxidant capacity which measures the water-soluble and fat-soluble in an extract shows a concentration dependency indicating antioxidant potentials of the nut extracts.