Analysis of fatty acids and phytosterols in ethanol extracts of Nelumbo nucifera seeds and rhizomes by GC-MS.

The purpose of this study was to investigate the fatty acid and phytosterol contents in ethanol extracts of lotus seeds and rhizomes. These ethanol extracts were extracted with hexane. The hexane extracts were hydrolyzed in a microwave reactor, and total fatty acids and phytosterols were analyzed. The hexane extracts were also subjected to silica gel column chromatography. Nonpolar components (triglycerides and steryl-fatty acid esters) were hydrolyzed, and then the contents were analyzed. Polar components (diglycerides, monoglycerides, fatty acids, and phytosterols) were analyzed directly. Seeds contained higher concentrations of fatty acids and phytosterols compared to rhizomes. Linoleic acid, palmitic acid, and oleic acid were the main fatty acid components in seeds and rhizomes, and most of them in seeds were in the ester form. In seeds, phytosterols existed mainly in the free form rather than in steryl-fatty acid ester form. β-Sitosterol was the most abundant phytosterol in seeds and rhizomes.