Discrimination of wild and domestic origin of sturgeon ova based on lipids and fatty acid analysis

This study was designed to discriminate different origins of sturgeon eggs (wild or domestic) based on their biochemical composition. Fatty acid profiles of neutral and phospholipid fractions of three populations of white sturgeon, Acipenser transmontanus (two domestic and one wild) and one population of wild lake sturgeon Acipenser fulvescens ova lipids were analyzed. Palmitic acid (16:0) was the dominant saturated fatty acid in both neutral and phospholipid fractions of egg lipids regardless of species or population origin. Levels of palmitoleic (16:1n - 7) and docosahexaenoic (22:6n - 3) acids were species specific irrespective of fish origin. Palmitoleic acid was found at a significantly (P < 0.05) higher level in lake sturgeon egg neutral lipids than in white sturgeon, The opposite was the case for 22:6n - 3. Other fatty acids, such as stearic (18:0) and oleic (18:1n - 9) acids, were origin specific rather than species specific. Stearic acid was found at significantly lower levels in wild fish egg neutral lipids than in domesticated fish ova, whereas 18:1n - 9 showed the opposite trend. Phospholipid fatty acids were much less variable between species and among populations. We demonstrated that sturgeons' environment, thus their diet along with species specific characteristic life history (i.e., freshwater or marine origin) play an important role and markedly influence fatty acid composition of their eggs. Thus, egg fatty acid profile can be a viable tool in discrimination of different sturgeon populations with respect to caviar source and can ultimately be used to protect endangered wild populations of sturgeon. (C) 2000 Elsevier Science B.V. All rights reserved.