Changes in lipid composition of different tissues of common octopus (Octopus vulgaris) during short-term starvation

Abstract

In this work, we study the variations in concentration (mg 100 g−1 dry weight) and total content (mg individual−1) of different lipid classes in muscle and the digestive gland of Octopus vulgaris during an 8-day starvation period. In all the samples analysed, polar lipids (PL) predominated in muscle (267.3–337.2 mg 100 g−1) compared with neutral lipids (66.9–104.7 mg 100 g−1). A significant positive tendency was observed in muscle for the content and concentration of monoglycerides as a consequence of starvation (P < 0.05). Furthermore, a higher cholesterol (CHO) content was detected in this tissue after the fourth day of starvation compared with the fed animals (P < 0.05). Neutral lipids predominated in the digestive gland (12 958–14 151 mg 100 g−1) compared with PL (3157–6517 mg 100 g−1), with triglycerides, free fatty acids and monoglycerides being the major lipid classes. The concentration of PL and monoglycerides showed a positive trend with starvation, while the triacylglycerol showed a negative tendency (P < 0.05). The results suggest that triglycerides and CHO are transported simultaneously from the digestive gland to the muscular tissues during starvation and the preferential use of PL and CHO during growth phases. It was estimated that lipids contributed 26% of the energy costs of the animals during starvation, mainly in the form of triglycerides from the digestive gland.