Characterization of Glycolipids in the Strain Chlorella pyrenoidosa

Plant-derived polar lipids have been reported to exhibit various beneficial effects on human health. The green alga Chlorella is known to be abundant in nutrients, including lipophilic components, and has varying nutrient content depending on the strain. In this study, to assess the nutritional functions of the strain Chlorella pyrenoidosa, we comprehensively analyzed the composition of fatty acids, polar glycerolipids, and sphingolipids. We found that n-3 polyunsaturated fatty acids (PUFAs) comprised 45.6 mol% of fatty acids in the total lipids and 62.2 mol% of n-3 PUFAs in the total lipids occurred in the glycolipids. Monogalactosyldiacylglycerol was the primary glycolipid class, and n-3 PUFA constituted 73.5 mol% of the fatty acids. Although glucosylceramide was observed in trace amounts, highly polar sphingolipids (HPSs), including glycosyl inositol phosphoryl ceramide, were found in much higher amounts compared to rice bran, which is a common source of sphingolipids. These results suggest that the examined Chlorella strain, which is abundant in glycolipids bearing n-3 PUFAs and HPS, is potentially useful as a dietary supplement for improving human health.