Polyphenolic content and antioxidant activity of Eugenia pollicina leaf extract in vitro and in model emulsion systems

• Published in: Food research international Vol. 44; no. 5; pp. 1190 - 1196
• Main Authors: Ramful, D., Aumjaud, B., Neergheen, V.S., Soobrattee, M.A., Googoolye, K., Aruoma, O.I., Bahorun, T.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-06-2011; Elsevier
• Subjects: Antioxidant efficacy; Antioxidants; Biological and medical sciences; Cosmetics; Emulsions; Eugenia pollicina; Fat industries; Flavonoids; Food industries; Foods; Fundamental and applied biological sciences. Psychology; Gallates; Lipids; Olive oil; Polyphenolics; Procyanidins; Soybean oil; Polyphenolics; Emulsions; Eugenia pollicina; Olive oil; Antioxidant efficacy; Soybean oil; Eugenia; Vegetable oil; Extract; Plant leaf; Edible oil; Antioxidant; In vitro; Emulsion; Plant part; Dicotyledones; Angiospermae; Myrtaceae; Spermatophyta; Models
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2010.09.024

The polyphenolic profile of a leaf extract of the Mauritian endemic plant, Eugenia pollicina, was assessed as a source of natural antioxidants. The amounts of flavan-3-ol derivatives determined by HPLC, were in the order of (−)-epicatechin (EC)>(−)-epigallocatechin gallate (EGCG)>(+)-catechin (C)>(−)-epicatechin gallate (ECG) with the levels of Procyanidin B2 and B1 dimers ranging from 1 to 3mg g−1 FW. The trolox equivalent antioxidant capacity and ferric reducing antioxidant power values were 796μmol g−1 FW and 302μmol g−1 FW respectively. E. pollicina extracts also strongly inhibited the FeCl3 and ascorbate-dependent microsome lipid peroxidation, a function that is linked to their flavonoid contents. The extent of DNA damage induced by the extract under study in the copper-phenanthroline assay was lower than the effect of a reference of 240μM ascorbate. E. pollicina extracts also inhibited lipid autoxidation in the 30% (v/v) olive oil and soybean oil oil-in-water (O/W) emulsions and was effective in slowing down the formation of hydroperoxides in the emulsions during 13days storage at 40°C as determined by the peroxide, conjugated diene and para-anisidine values. The high levels of total phenolics, flavonoids and procyanidins measured indicate that E. pollicina is a potential source of antioxidants relevant to the maintenance of oxidative stability of the food matrix, cosmetics and/or pharmaceutical preparations.