Phenolic compounds in the brown seaweed Ascophyllum nodosum: distribution and radical‐scavenging activities
- 25 August 2010
- journal article
- research article
- Published by Wiley in Phytochemical Analysis
- Vol. 21 (5), 399-405
- https://doi.org/10.1002/pca.1210
Abstract
Introduction – Phenolic compounds are metabolites exhibited at high levels in Phaeophyceae. Although several studies have been conducted on total phenol contents, no one to our knowledge has dealt with the contents of phenolic compounds and antioxidant activities on purified fractions. Objective – The purpose of this study was the extraction and purification of phenolic compounds from the brown seaweed Ascophylllum nodosum, to determine both their distribution and their radical-scavenging activities, and to obtain a sufficiently purified oligophenolic fraction to perform an RP-HPLC analysis on molecules with a molecular weight (MW) < 2 kDa. Methodology – Phenolic compounds were separated and purified by liquid–liquid extraction, tangential ultrafiltration and dialysis. Then, the contents of both phenolic compounds and radical-scavenging activities were measured by the Folin–Ciocalteu reagent, and DPPH and ABTS assays. NMR analysis was performed to validate the process. RP-HPLC with a C18 column was performed on the oligophenolic fraction, using a novel method developed in this study. Results – Seven fractions were obtained as a function of polarity and molecular weight. Among them, the fraction containing phenolic compounds with a MW ≥ 50 kDa appeared to be the most active, correlated with the content of phenolic compounds. Conclusion – This work constitutes a step forward in the separation and purification of bioactive phlorotannins and represents a prerequisite for further investigations into their structural characterisation and distribution in A. nodosum.Keywords
This publication has 20 references indexed in Scilit:
- Intra-thallus phlorotannin content and antioxidant activity in Phaeophyceae of temperate watersBotanica Marina, 2006
- Co-occurrence and antioxidant activities of fucol and fucophlorethol classes of polymeric phenols in Fucus spiralisBotanica Marina, 2006
- Interspecific and temporal variation in phlorotannin levels in an assemblage of brown algaeBotanica Marina, 2004
- Fucols and Phlorethols from the Brown Alga Scytothamnus australis Hook. et Harv. (Chnoosporaceae)Botanica Marina, 2003
- Induction, exudation and the UV protective role of kelp phlorotanninsAquatic Botany, 2002
- Phenols in reproductive and somatic structures of lichens: a case of optimal defence?Oikos, 2000
- Phlorotannins versus other factors affecting epiphyte abundance on the kelp Ecklonia radiataOecologia, 1997
- Phenotypic variation in polyphenolic content of the tropical brown alga Lobophora variegata as a function of nitrogen availabilityMarine Ecology Progress Series, 1995
- Biogeographic comparisons of marine algal polyphenolics: evidence against a latitudinal trendOecologia, 1992
- Polyphenols in brown algaeFucus vesiculosus andAscophyllum nodosum: Chemical defenses against the marine herbivorous snail,Littorina littoreaJournal of Chemical Ecology, 1981