Abstract: A process for separating polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from less saturated long chain fatty acids (LCFAs) in a lipid composition, wherein said PUFAs and LCFAs are present as (i) triglycerides, or (ii) free fatty acids or monoalkyl esters, by exchange of at least a portion of LCFAs with short and/or medium chain fatty acids (MCFAs). The process can suitably be employed on marine derived oil, marine oil 2 derived oil products and other sources of PUFAs, including PUFA-rich singe cell oils (SCOs), and oils from genetically modified organisms with a modified lipid metabolism. The inventive process is based on novel use of lipases and distillation techniques, selectively chemically modifying species in the substrate material such that the desired species and chemically similar species become sufficiently dissimilar to be separable.

Abstract: A process for separating polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapen-taenoic acid (EPA) from less saturated long chain fatty acids (LCFAs) in a lipid composition, wherein said PUFAs and LCFAs are present as (i) triglycerides, or (ii) free fatty acids or monoalkyl esters, by exchange of at least a portion of LCFAs with short and/or medium chain fatty acids (MCFAs). The process can suitably be employed on marine derived oil, marine oil 2 derived oil products and other sources of PUFAs, including PUFA-rich singe cell oils (SCOs), and oils from genetically modified organisms with a modified lipid metabolism. The inventive process is based on novel use of lipases and distillation techniques, selectively chemically modifying species in the substrate material such that the desired species and chemically similar species become sufficiently dissimilar to be separable.

Abstract: Novel acylglycerides are disclosed comprising mono-, di- and triacylglycerides characterized by predominantly containing the conjugated linoleic acids t9,c11- and c10,t12 octadecadienoic acids to the exclusion of 11,13-, 8,10- and trans,trans isomers.

Abstract: Marine oil compositions which contain EPA and DHA as free acids or hexyl esters are esterified with ethanol in the presence of a lipase catalyst under essentially organic solvent-free conditions and separated by distillation.

Abstract: A composition is for feeding aquacultural prey organisms such as Artemia and rotifiers, comprising a lipid component comprising at least 25 wt % of phospholipids and providing a DHA content of at least 30 wt %. The lipid component is preferably derived from marine organisms such as fishmeal, phytoplankton or zoo plankton biomass. The composition is used for providing prey organisms having a high content of highly-unsaturated fatty acids (HUFAs) suitable for aquaculture of fish including halibut, turbot, bass and crustaceans and molluses.

Abstract: A method of rearing aquatic species is provided, comprising feeding the aquatic species during at least part of the larval and/or post-larval state with prey organisms, such as Artemia or rotifers, having in their total lipid content a DHA content of at least 12 wt %. The method is suitable for the rearing of fish species such as halibut, turbot, bass, bream and flounder. The total lipid content of the prey organisms further including highly unsaturated fatty acids comprising 18:3, 18:4, 20:4, 20:5 (EPA) and 22:5 fatty acids. Also the prey organisms include 5 to 35 wt % phospholipids of the total lipid content, wherein the total lipid content is at least 20 wt % on a dry weight basis.

Abstract: A method is provided for producing prey organisms such as Artermia and rotifers, for feeding aquacultural organisms in particular at the larval stage. The method comprises cultivating the prey organisms during at least part of their life cycle in an aqueous medium comprising at least one lipid component having a DHA content of at least 30 wt %. The enriched prey organisms preferably have a DHA content of at least 12 wt % of their total lipid content. The prey organisms are suitable feed for larvae of fish including halibut, turbot, bass, and flounder, and crustaceans and molluscs.

Abstract: Novel acylglycerides are disclosed comprising mono-, di- and triacylglycerides characterized by predominantly containing the conjugated linoleic acids t9,c11- and c10,t12 octadecadienoic acids to the exclusion of 11,13-, 8,10- and trans,trans isomers.

Abstract: A composition is for feeding aquacultural prey organisms such as Artemia and rotifiers, comprising a lipid component comprising at least 25 wt % of phospholipids and providing a DHA content of at least 30 wt %. The lipid component is preferably derived from marine organisms such as fishineal, phytoplankton or zoo plankton biomass. The composition is used for providing prey organisms having a high content of highly-unsaturated fatty acids (HUFAs) suitable for aquaculture of fish including halibut, turbot, bass and crustaceans and molluses.

Abstract: A method is provided for producing prey organisms such as Artermia and rotifers, for feeding aquacultural organisms in particular at the larval stage. The method comprises cultivating the prey organisms during at least part of their life cycle in an aqueous medium comprising at least one lipid component having a DHA content of at least 30 wt %. The enriched prey organisms preferably have a DHA content of at least 12 wt % of their total lipid content. The prey organisms are suitable feed for larvae of fish including halibut, turbot, bass, and flounder, and crustaceans and molluscs.

Abstract: Marine oil compositions which contain EPA and DHA as free acids are esterified with glycerol in the presence of a lipase catalyst under reduced pressure and essentially organic solvent-free conditions to form a free fatty acid fraction enriched in at least one of EPA and DHA.

Abstract: A method of rearing aquatic species is provided, comprising feeding the aquatic species during at least part of the larval and/or post-larval stage with prey organisms, such as Aremia or rotifers, having in their total lipid content a DHA content of at least 12 wt %. The method is suitable for the rearing of fish species such as halibut, turbot, bass, bream and flounder.

Abstract: This invention relates to a process for treating an oil composition containing saturated and unsaturated fatty acids in the form of triglycerides, with at least some of the unsaturated fatty acids being polyunsaturated, in order to obtain a refined product with a higher concentration of the polyunsaturated fatty acids.

Abstract: The present invention relates to a process for preparing a triglyceride, comprising reacting glycerol with a polyunsaturated fatty acid having at least 20 carbon atoms and at least three double bonds or a C.sub.1-4 alkyl ester thereof, for a reaction time in the range of 24-48 hours at a temperature between 40.degree. and 80.degree. C. in the presence of a mixture of lipase A and lipase B obtained from Candida antarctica which is immobilized, to form (i) the triglyceride and (ii) water or a C.sub.1-4 alcohol, while removing the water or the C.sub.1-4 alcohol during the reaction, and recovering the triglyceride.