Isolation of fucoxanthin and fatty acids analysis of Padina australis and cytotoxic effect of fucoxanthin on human lung cancer (H1299) cell lines

Abstract

Fucoxanthin has been successfully isolated from species of Malaysian brown seaweed, namely Padina australis. The purity of the fucoxanthin is >98% as indicated by high performance liquid chromatography analysis. This seaweed also contains a considerable amount of unsaturated fatty acids. Thirteen fatty acids were detected with gas chromatography. However, fatty acid methyl ester (FAMEs) of eicosapentanoic acid (C20:5n-3), arachidonic acid (C20:4n-6), linoleic acid (C18:2n-6) and alpha-linolenic acid (C18:3n-3) contents of P. australis were found to be 2.06, 9.50, 6.37, and 2.83%, respectively. For saturated fatty acids, palmitic acid (C16:0) was found to be the major fatty acid with about 23.97%. Furthermore, data obtained from the methyl thiazolyl tetrazolium (MTT) assay indicated that fucoxanthin reduced the viability of H1299 cell lines, showing an IC₅₀ value of 2.45 mM.

Key words: Brown seaweed, Padina australis, fucoxanthin, fatty acid methyl ester, H1299 cell lines, human lung cancer, MTT assay.