Volatile Constituents, Antioxidant and Insecticidal Activities of Essential Oil from the Leaves of Thaumatococcus Danielli (Benn.) Benth. From Nigeria

Abstract

The volatile constituents from the leaf oil of Thaumatococcus danielli (Benn.) Benth. growing in Nigeria was studied by GC and GC-MS. Twenty-one constituents were characterized representing 95.8% of the total oil. The major components of the oil were octadecamethyl cyclononasiloxane (48.3%), phytol (12.9%) and 6,10,14-trimethyl-2-pentadecanone (9.3%). The antioxidant activity of the oil (10–50 mg/mL) was evaluated by measurement of 1,1-diphenylpicryl-hydrazyl (DPPH) radical, metal chelating and nitric oxide radical methods. The essential oil showed no metal chelating activity, but, displayed significant antioxidant activity against 1,1- diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide radicals with IC50 values of 16.32 and 24.68 mg/mL, respectively, compared to synthetic antioxidants: butylated hydroxyanisole, butylated hydroxytoluene, ascorbic acid and α-tocopherol with (IC50 ≤ 17.96 mg/ mL). The insecticidal activity was assayed against Sitophilus zeamais and the result showed LC50 value of 345.2 mg/mL after 72 H.