THE STABILITY OF DOCOSAHEXAENOIC ACID IN 2 ARTEMIA SPECIES FOLLOWING ENRICHMENT AND SUBSEQUENT STARVATION

Two Artemia species( Artemia franciscana, GSL strain and a population from Artemia sinica, ARC No. 1188) were enriched with two different em ulsions containing high levels of docosahexaenoic acid (DHA) (23 and 4 4% of total fatty acids, respectively) in filtered seawater (30 ppt) a t 28 degrees C. After enrichment nauplii were starved for 72 h at thre e different temperatures (6.1, 12.2 and 22 degrees C). Following enric hment the DHA content and DHA/EPA ratio reached a maximum 41.2 and 42. 8 mg g(-1) dry weight and 1.88 and 2.09 in A. franciscana and A. sinic a, respectively. During starvation at 12.2 degrees C the DHA content i n A. franciscana decreased steadily throughout the starvation period t owards 1.11-2.89 mg g(-1) dry weight (DHA/EPA ratio of 0.4) after 72 h , whereas in A. sinica the DHA content was > 20 mg g(-1) dry weight (D HA/EPA ratio of 1.7-2). A quantitative reduction of DHA in A. sinica w as observed only during the first 24 h of the starvation period. The d egradation rate of DHA in A. franciscana increased with rising tempera ture (22 degrees C) and decreased at the lowest temperature (6.1 degre es C). This was not the case for A. sinica, during starvation at diffe rent temperatures the DHA level in A. sinica remained at a relatively high and constant level. (C) 1997 Elsevier Science B.V.