No abstract

The lipid and fatty acid composition of the hepatopancreas and muscle of the prawn, Penaeus japonicus, were analyzed. The hepatopancreas was the main lipid storage organ, triglycerides and phospholipids being its major lipid components, while muscle contained mainly phospholipids. The fatty acid compositions of total lipids from the hepatopancreas and muscle were similar to those in other marine animals. The major fatty acids were palmitic (16:0), oleic (18:1n-9), eicosapentaenoic (20:5n-3), and docosahexaenoic (22:6n-3) acids. The monoglycerides, diglycerides, triglycerides, and cholesterol esters from the hepatopancreas and muscle exhibited similar fatty acid patterns, but each lipid fraction was characterized by a specific paraffin chain composition. A blue carotenoprotein (lambda max = 640 nm) containing astaxanthin was also extracted and purified from the hypodermis of the prawn. This blue carotenoprotein has a molecular weight of ca. 280,000, which is much lower to those given for other crustaceans. The carotenoid prosthetic group was released from the carotenoprotein by the addition of acetone, and showed a hypsochromic shift to 470 nm and the characteristic shape of free ketocarotenoids. TLC, infrared spectroscopy, chemical reduction, spectrophotometry, and qualitative analysis by HPLC were used to identify the astaxanthin as a unique chromophore group of the blue carotenoprotein. Moreover, HPLC studies suggested all-trans-astaxanthin to be the main component, which was accompanied by an epimer and its cis-isomer.

The present study confirms that N,Nodimethylformamide for the extraction of chloroplast pigments from vegetable tissues shows no differences from the usual acetone or methanol. Therefore, it can be applied to fats, as it allows separation of lipids and pigments by means of phase distribution between light petroleum ether and N,Ndimethylformamide. The ether phase retains the decolored fatty matter, and the pigments dissolved in N,Ndimethylformamide can be recovered totally unaltered.This method has been applied to oleoresins and oils from different products and origins. Satisfactory results have been obtained in terms of the degree of decoloration and the percentage of oil recovered. At the same time, the unaltered pigment concentrate obtained from the hypophase could be used as a color enhancer in the chemico-pharmaceutical industry.