Seasonal variation in fatty acid profiles of Holothuria poli (Delle Chiaje, 1823) from Monastir Bay (Tunisia): implications for trophic markers and lipid nutritional quality assessment

ABSTRACT

This study investigated the seasonal variations in the proximate composition, fatty acid profile, lipid nutritional quality, and diet composition of Holothuria poli collected from Monastir Bay. Our findings revealed significant seasonal variations in protein, lipids, and ash contents, with the highest protein levels recorded during the summer and peak lipid levels observed in winter. Total monounsaturated fatty acids peaked in both winter and summer, while total saturated fatty acids reached their maximum in autumn. These variations in biochemical compositions were closely linked to the sea cucumber's dietary preferences. Our results demonstrated that H. poli exhibits a diverse diet, consuming bacteria, detritus, diatoms, zooplankton, and algae, with notable seasonal fluctuations. Moreover, the EPA + DHA content and the atherogenic (AI), thrombogenic (TI), and hypocholesterolemic/hypercholesterolemic (H/H) indexes align with the ranges characteristic of high-quality seafood, though marked variations are evident among seasons. A principal component analysis illuminated the dynamic seasonal shifts in Holothuria poli's dietary habits and lipid nutritional characteristics, offering valuable insights into its ecological adaptations and potential repercussions for marine food webs. These findings underscore the intriguing interplay between fatty acid composition, lipid nutritional quality, dietary preferences, and environmental factors in sea cucumbers.

KEYWORDS:

• Sea cucumber
• fatty acid
• lipid quality indices
• trophic links
• multivariate analysis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethical approval

This study followed the ethical guidelines for the use of laboratory animals established by the Bioethical Commission for Scientific Research at the Higher Institute of Biotechnology in Monastir, located on Tahar Haddad Street, (B.P 74), Monastir, 5000, Tunisia.

Author contributions

M.J., and T.G. designed this study. M.J. carried out the main experiments and analysed the data. H.G. provided the material and equipment facilities. Z.B., and J.J. co-wrote the manuscript. All the authors reviewed and approved the final manuscript.

Additional information

Funding

This work was supported by a fund from the Ministry of Higher Education and Scientific Research, University of Monastir, Tunisia (Research Laboratory of Bioresources: Integrative Biology & Valorization (LR 14ES06), High Institute of Biotechnology of Monastir, Tunisia).