Human cerumen was separated by column chromatography into the following groups of compounds: hydrocarbons, squalene, wax esters and cholesterol esters, triacylglycerols, free fatty acids, free fatty alcohols, monoacylglycerols, free cholesterol, free sterols, and free hydroxy acids. The groups of compounds obtained were examined in detail by gas chromatography and gas chromatography-mass spectrometry. In total, about one thousand compounds have been identified.
Unusual fatty acids with 24, 26, and 28 carbon atoms were found in triacylglycerols (TAGs) isolated from fat body tissue of bumblebee Bombus pratorum. The most abundant one was (Z,Z)-9,19-hexacosadienoic acid. Its structure was determined by mass spectrometry after derivatization with dimethyl disulfide and by infrared spectroscopy. ECL (equivalent chain length) values of its methyl ester were determined on both DB-1 and DB-WAX capillary columns. (Z,Z)-9,19-Hexacosadienoic acid is quite rare in nature. So far it has been identified only in marine sponges, and this work is the first evidence of its occurrence in a terrestrial organism. HPLC/MS analysis of the bumblebee TAGs showed that (Z,Z)-9,19-hexacosadienoic acid is present in one third of all TAG molecular species. As it was found in all sn-TAG positions, it is likely that (Z,Z)-9,19-hexacosadienoic acid is transported to tissues. Interestingly, labial gland secretion of B. pratorum was found to contain (Z,Z)-7,17-pentacosadiene, a hydrocarbon with markedly similar double bond positions and geometry. Possible biosynthetic relationships between these two compounds are discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.