Antioxidant properties and polyphenol contents of different parts of coriander (Coriandrum sativum L.) fruit

This study is designed to examine the phenolic content and composition and antioxidant activity of the methanol extracts of Coriandrum sativum L. seed, whole fruit and pericarp. Seed presented the higher antioxidant capacities with 77.46 mg GAE/g followed by whole fruit (65.58 mg GAE/g) and pericarp (61.41 mg GAE/g). Total phenol contents were 15.55 mg GAE/g in seed, 12.10 mg GAE/g in whole fruit and 2.92 mg GAE/g in pericarp. Concerning total flavonoid contents, they were 13.20 mg CE/g in whole fruit, 19.98 mg CE/g in seed and 1.01 mg CE/g in pericarp. Condensed tannins were present in whole fruit and seed with 0.70 and 0.62 mg CE/g, respectively. Pericarp showed the lower tannin content (0.24 mg CE/g). Among the polyphenols studied, 18 were identified in whole fruit, 15 in seed and 10 in pericarp. The main phenolic compound was dihydroxyphenolic acid with 85.01 mg/100 g in whole fruit, 101.5 mg/100 g in seed and 10.52 mg/100 g in pericarp. Antioxidant activities of the methanolic extract from coriander fruit different parts were evaluated by using DPPH radical scavenging, beta-carotene-linoleic acid bleaching and the reducing power tests. All fruit parts extracts showed remarkable DPPH radical scavenging activity with IC50 values of 42 and 32 mu g/mL in seed and whole fruit, respectively. However, in pericarp extract DPPH scavenging ability was higher than that of BHT (IC50 = 25 mu g/mL). The extracts had lower beta-carotene bleaching activity than BHA and BHT. Coriander fruit extracts presented a very low reducing power ability (EC50 approximate to 700 mu g/mL) compared to ascorbic acid (EC50 = 40 mu g/mL).