Fatty acids and fat soluble vitamins content of Black Sea round goby (Neogobius melanostomus Pallas, ۱۸۱۴) during fishing seasons

The aim of the present study was to determine and compare the seasonal changes in the proximate composition, fatty acids profile and fat soluble vitamins content in spring and autumn goby (Neogobius melanostomus) caught from the Bulgarian Black Sea waters. The proximate composition (moisture, protein and total lipid) has been determined according to AOAC (۱۹۹۰).  Analysis of fatty acid methyl esters has been performed by GC/MS system. Vitamins A, D۳ and E were analysed using RP-HPLC system. Protein was in the range ۱۸.۱۰ – ۱۸.۷۵ %, fat content was: ۱.۶۰-۲.۶۱g ۱۰۰g-۱ wet weight (w.w.). The fatty acids (FA) and vitamins contents showed significant seasonal changes. The spring goby was characterized with low saturated fatty acids (SFA, ۳۱.۸ %), high mono unsaturated fatty acids (MUFA, ۳۴.۸۶ %) and polyunsaturated fatty acids (PUFA, ۳۳.۳۴ %). In both seasons omega-۳ (n-۳) PUFA levels were higher than omega-۶ (n-۶) PUFAs. Higher amounts of alpha-tocopherol (۶۱۴.۹ μg ۱۰۰g-۱w.w.) and all-trans retinol (۱۴.۸ μg ۱۰۰g-۱ w.w.) were found in autumn samples, whereas cholecalciferol (۴.۹ μg ۱۰۰g-۱ w.w.) - in spring goby. Regardless of the observed seasonal changes of nutritional quality, goby species is an excellent source of analysed components, especially of n-۳ PUFA, and can be recommended for healthy human diet.

Keywords:

Black Sea , Neogobius melanostomus , Omega-۳ fatty acids , Fat soluble vitamins