Differences between Myrtle Fruit Parts (Myrtus communis var. italica) in Phenolics and Antioxidant Contents

Authors


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Abstract

The present work aimed to study the phenolics and antioxidant activity of the methanol extracts of Myrtus communis var. italica whole fruit, seed and pericarp. The total phenol contents varied between different fruit parts; seed extract had higher total phenol content (23.87 mg GAE/g DW) than whole fruit (13.73 mg GAE/g DW) and pericarp (2.76 mg GAE/g DW) extracts. Significant differences were also found in total tannin contents among different myrtle parts, representing 18.01 mg GAE/g DW in seed, 9.11 mg GAE/g DW in whole fruit and 0.79 mg GAE/g DW in pericarp. Concerning total flavonoid contents, the highest values were observed in pericarp (1.33 mg GAE/g DW) and whole fruit (1.21 mg CE/g DW) extracts. The condensed tannin content was relatively low in all samples tested, the highest value being found in whole fruit extract (0.96 mg CE/g DW). The high-performance liquid chromatography analysis indicated that the main phenolic class was hydrolysable tannins (gallotannins) in seed (80.20%, 8.99 mg/g MS) while the pericarp was characterized by a predominance of anthocyanins (75.40%, 3.74 mg/g DW). The whole fruit contained both hydrolysable tannins 40 (10.31%, 0.69 mg/g DW) originated from seed and anthocyanins (69.36%, 4.64 mg/g DW) originated from pericarp. Antioxidant activities of the methanolic extract from different fruit parts were evaluated by using 1,1-diphenyl-2-picrylhydrazyl radical scavenging, β-carotene-linoleic acid bleaching and reducing power assays. In all tests, the seed was the part with highest antioxidant potential.

Practical Applications

Nowadays, the interest in naturally occurring antioxidants has considerably increased for use in food, cosmetic and pharmaceutical products to replace synthetic antioxidants, which are being restricted because of their carcinogenicity. In this study, total phenolic contents and antioxidant properties of myrtle fruit parts (Myrtus communis var. italica) were researched.

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