Fatty acid and sterol composition of gametophytes and sporophytes of Chondrus crispus (Gigartinaceae, Rhodophyta)

Abstract

Fatty acids and sterols of gametophytes and sporophytes of Chondrus crispus were isolated and identified. Although chemical variation in the proportions of other natural compounds (eg. different carrageenan type) between gametophytes and sporophytes has already been observed, this is the first comparative study of the lipid composition in both generations. The content of fatty acids and sterols in gametophytes (0.710 and 0.190 mg g^-1 dry weight respectively) was higher than in sporophytes (0.622 and 0.113 mg g^-1 dry weight). The main fatty acids were palmitic, palmitoleic, oleic, arachidonic and eicosapentaenoic acids. These five fatty acids represented more than 78% of the all fatty acid composition in both generations. In addition unsaturated fatty acids were present in a much greater quantity (>80%) than saturated fatty acids. However, differences in the distribution of fatty acids between the two generations were observed. Gametophytes demonstrated higher amounts of monounsaturated fatty acids while sporophytes had a relatively higher content of saturated and polyunsaturated fatty acids. The major sterol in both generations was cholesterol (> 94%). Differences were also observed in the sterol distribution between gametophytes and sporophytes, the former containing smaller amounts of 7-dehydrocholesterol and stigmasterol, while the latter had smaller amounts of 22-dehydrocholesterol, campesterol and sitosterol. Gametophytes were lacking 24-methylenecholesterol. Fatty acids and sterol of algal class, families and sometimes even species are characteristic to those particular taxa, and could be useful as chemotaxonomic markers. The results of this study showed that intra-specific variation in algae can be occured.