Oil Extracted from Two Discarded Species of the Mediterranean Sea as Raw Material for the Production of Structured Lipids: Seasonal Characterization of their Fatty Acids Regiodistribution.
Morales-Medina, R.; Garcia-Moreno, P.J.; Perez-Galvez, R.; Muñio M.; Guadix A.M. and Guadix E.M.
Department of Chemical Engineering. University of Granada, Spain
Tel:+34958240532; Fax: +34958248992; E-mail: rocio_morales@ugr.es

The aim of this work was to seasonally study the nutraceutical properties  and the fatty acids regiodistribution of the oil extracted from two discarded fish species in the Alboran Sea namely:  small-spotted catshark (Scyliorhinus canicula) and bogue (Boops boops). 
The lipidic profile was employed to calculate the atherogenity and thrombogenicity indexes and the hypocholesterolaemic/ hypercholesterolaemic ratio. 
Both species presented PUFA as the majoritarian fraction in both, the global and the sn-2 profile, and healthy values for the nutritional indexes along the year. The average PUFA content located in sn2 was 62.7±7.1% and 59.1±6.3% (molar basis) for small-spotted catshark and bogue, respectively. This high percentage is mainly due to the sn2 regiospecificity that DHA presented: 51.3±10.0% (small-spotted catshark) and 45.4±7.5% (bogue). On the contrary, EPA presented specificity towards positions sn1(3) an average percentage of 3.65±0.65mol% was located in the central bond of glycerol.

Due to their high content of DHA, these oils might be employed for infant nutrition. Hence, they can be considered as source for the synthesis of structured lipids by processes which preserve the central position of the fatty acids as two-step enzymatic treatments (alcoholysis and esterification) or selective hydrolysis.