Comparing the antioxidant activities of tomato seed oil extracted from two varieties of tomato fruits

Abstract

Comparing the antioxidant activities of tomato seed oil extracted from two varieties of tomato fruits (Riogrande and Roma VF) demonstrated by five spectrophotometric methods: DPPH, β- carotene linoleic antioxidant, HRSA, ORAC, FRAP. Tomato seed is the major by-product of the tomato paste manufacturing industry in the world today. The tomato seed was extracted from healthy tomato fruits of the two varieties and were washed with water and dried in an oven at 60oC for 3 days, and milled to powder. Ten gram of the powdered samples was placed in a soxhlet extractor, using 300 ml of n- Hexane, and allowed to boil at 40-60°C for 6 hours repeatedly to obtain the oil. The oil was placed in a water bath at 70°C to remove the excess n-Hexane. The results showed that tomato seed oil (TSO) is stable, translucent and highly penetrating oil and the refractive index, Density and the specific gravity of the oil of both varieties are all in line with the FAO/WHO standard. The fatty acid composition results showed that TSO is an excellent source of essential fatty acids. Though Roma VF seed oil at a lower concentration of DPPH (43.270±0.028), β- carotene linoleic antioxidant (15.855±0.035), FRAP (10.765±0.021) and HRSA (31.010±0.014) demonstrated higher oxidation rates of scavenging free radicals, chelating prooxidative metals, quenching singlet oxygen and photosensitizers, and inactivating lipoxygenase compared to the Riogrande seed oil which had the only lower reducing potential of ORAC (1.480±0.014).