Murta leaves (Ugni molinae turcz) as a source of antioxidant polyphenols

rubilar, M.; Pinelo, M; Ihl M.; Scheuermann E.; Sineiro J.; Nunez, MJ

Abstract

Extracts from Murta leaves are used by Chilean natives for their benefits on health and cosmetic properties, which are mainly due to the presence of polyphenolic compounds. Extraction of such compounds is strongly influenced by several variables, the effects of which are studied in this work; the antioxidant power of the resulting extracts was measured by two different methods [2,2-diphenyl-1-picrylhydrazyl (DPPH) and thiobarbituric acid reactive substances (TBARS)]. On the whole, maximum values of polyphenolic yields and antiradical power (DPPH method) were attained at 50°C (from 25 to 50°C) and a solvent-to-solid ratio (v/w) of 15:1 (15:1-25:1). The solvents assayed were ethanol, methanol, and water. The highest polyphenolic yield values (2.6% expressed as gallic acid) were reached with methanol, whereas maximum EC 50 was attained by the ethanol extract (0.121 mol gallic acid/mol DPPH). Contact time was shown to have only a slight influence in alcoholic extraction, while in water a remarkable effect of increasing contact times (30-90 min)was observed. Just water was the solvent that offered the best result when the antioxidant power was measured by the TBARS method. High-performance liquid chromatography-mass spectrometry analysis revealed the presence of polyphenols, basically flavonols and flavanols, sometimes glycosilated; myricetin and quercetin glycosides were detected in all extracts, whereas epicatechin was present in alcoholic extracts and gallic acid was only present in water. © 2006 American Chemical Society.

Más información

Título según WOS: Murta leaves (Ugni molinae turcz) as a source of antioxidant polyphenols
Título según SCOPUS: Murta leaves (Ugni molinae Turcz) as a source of antioxidant polyphenols
Título de la Revista: JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
Volumen: 54
Número: 1
Editorial: AMER CHEMICAL SOC
Fecha de publicación: 2006
Página de inicio: 59
Página final: 64
Idioma: English
URL: http://pubs.acs.org/doi/abs/10.1021/jf051571j
DOI:

10.1021/jf051571j

Notas: ISI, SCOPUS