Lipid composition of the red alga Tichocarpus crinitus exposed to different levels of photon irradiance
- 作者：Khotimchenko ; Svetlana V. ; Yakovleva ; Irina M.
- 关键词：Tichocarpus crinitus ; Rhodophyta ; Algae ; Light ; Solar irradiance ; Fatty acids ; Glycolipids ; Lipids ; Eicosapentaenoic acid
- 刊名：Phytochemistry
- 出版年：2005
- 期刊代码：85_00319422
- 类别：ch
- 出版时间：January, 2005
- 卷：66
- 期：1
- 页码：73-79
- 文件大小：288 K
摘要
We examined variations in the lipid composition of the marine red alga Tichocarpus crinitus exposed to different levels of photon irradiance: 70芒芒芒80%and 8芒芒芒10%of the incident photosynthetically active radiation (PAR). The content of storage and structural lipids was significantly affected by the light intensity. Exposure of T. crinitus to low light conditions induced an increase in the abundance of structural components of the cell membranes, especially sulfoquinovosyldiacylglycerol, phosphatidylglycerol (PG) and phosphatidylcholine, while growth of algae at high light intensity resulted in a 1.5-folder increase in the level of storage lipids, i.e. triacylglycerols. There were no significant differences in the fatty acid composition of the total lipid pool in algae grown under different light conditions. However, the content of the most unsaturated acid, 20:5n芒芒芒3, was slightly higher in T. crinitus under 8芒芒芒10%PAR compared to those at 70芒芒芒80%PAR. Each lipid class was found to have a characteristic fatty acid composition. The relative proportions of fatty acids esterifying monogalactosyldiacylglycerol (MGDG) and PG were significantly affected by irradiance conditions. Exposure of algae to low light resulted in increase in the content of 20:5n芒芒芒3 in MGDG and in decrease in the level of this acid in PG. The concentration of trans-16:1 acid in PG increased in algae grown under high light intensity. Light conditions influenced on total lipid content, which made up 4.2芒芒0.5 and 3.4芒芒0.3mgg芒芒芒1 fresh weight in algae exposed to 8芒芒芒10%PAR and 70芒芒芒80%PAR, respectively. We suggest that variations in the lipid composition of T. crinitus exposed to different levels of light intensity may be a response of alga to light conditions and it can be considered as one of the mechanisms of adaptation of T. crinitus to varying incident light intensity.