PHYSICO-CHEMICAL PROPERTIES AND ANTIOXIDANT ACTIVITIES OF OIL FROM PURSLANE (Portulaca oleracea L.) SEED, LEAF AND STEM

Abstract

Portulaca oleracea L. commonly known as Purslane is a herbaceous weed. Purslane is a very good source of alpha Linolenic acid, which is an omega-3- fatty acid. The aim of this study was to determine the Physico chemical properties and antioxidant activities of oil from purslane leaf, stem and seed with respect of major quality parameter. The oil extraction and oil qualities analysis were carried out in animal nutrition and biotechnology laboratory respectively. The major parameter is oil content, specific gravity, acid value, DPPH, ascorbic acid, and peroxide value. Physicochemical properties of oil from seed, leaf and stem of purslane (Portulaca oleracea) indicated that significantly the highest oil content was observed in seed (11.25%) using solvent extraction method. The highest specific gravity was recorded for seed oil (1.10 w/w) followed by leaf oil (0.73 w/w) with nonsignificant difference. The peroxide value was found to be the highest for seed oil but the least for stem oil with nonsignificant difference. Significantly the highest ascorbic acid (vitamin C) content was recorded for purslane seed oil (41.67%) followed by leaf oil (32.29%). Likewise, the highest DPPH activity was obtained for leaf oil (12.55%) followed by seed oil (2.05%). However, the peroxide scavenging indicated to be the highest for stem oil (0.70%) and the least for leaf oil (0.35%) insignificantly. These indicate that leaf and seed oils have shown more quality than stem oil. The plot for PC2 vs. PC1 indicated that oil content, specific gravity, peroxide value, ascorbic acid and DPPH having close PC1 and PC2 scores (with vector angle <900) showing similar/correlated effects while these parameters with HPSC and FFA have vector angle greater than 900 showing opposite effects or more divergence. Furthermore, HPSC, FFA and AV have similar effect since their vector angle <900. That is the lower amount of HPSC, FFA and AV the more the oil quality while the oil content, specific gravity, peroxide value, ascorbic acid and DPPH, the higher the oil quality.