Fatty acid composition of Bulgarian Black Sea fish species

Abstract

The fatty acid compositions of three Black Sea fish species turbot (Pseta maxima), red mullet (Mullus barbatus ponticus) and garfish (Belone belone) were investigated. This species are considered as preferred for consumption in Bulgaria. Lipid extraction was done according to the Bligh and Dyer method. The fatty acid composition was determined by GC/MS. The saturated fatty acids amounts were 38.32 % for turbot, 35.44 % red mullet and 42.90% for garfish. Monounsaturated fatty acids were found in lowest level in comparison with other groups for garfish (23.65%) and turbot (24.85%) while for red mullet they have a highest value -37.56%. Omega 3 polyunsaturated fatty acids as eicosapentaenoic (C 20:5 omega 3, EPA) and docosahexaenoic (C 22:6 omega 3, DHA) acids were found in highest levels in turbot (22.26%) and garfish (21.80%) and in lowest values of red mullet (9.35%). The results showed that the fish examined are good source of omega 3 polyunsaturated fatty acids, resulting in a very favourable omega 3 / omega 6 ratios, especially in turbot and garfish.

Fish Lipids as a Valuable Source of Polyunsaturated Fatty Acids

“…The n-6 PUFA deficiency symptoms are dermatitis, growth retardation and infertility in relation to its biological function: LA is a structural component of the skin ceramides, acting as a water barrier; ARA is a precursor of eicosanoids. N-3 deficiency is responsible for insulin resistance and metabolic syndrome, brain metabolic abnormalities, liver steatosis and non-alcoholic fatty liver disease [23]. Furthermore, deficiency of n-3 PUFA leads to a loss of DHA in the brain and retina-rod outer segment phospholipids with a compensatory replacement by 22:5 n-6.…”

“…Several studies report that cold-water fish contains higher amounts of n-3 PUFA. Water temperature seems to be an important abiotic factor influencing such amounts [23,24]. A comparison between the n-3 and n-6 PUFA content and the n-6/n-3 FA ratio in commercially important Bulgarian fish species and internationally published data for the same species is shown in Table 1.…”

“…Some of the proven beneficial biological functions of dietary n-3 PUFAs in the organism are related to the provision of energy and carbon atoms; the capability to reduce the amount of serum lipids, EPA as a precursor for "n-3 eicosanoids" which directly influences the vascular physiology and the vascular system; the specific role of DHA in the membrane function, especially in the retina and the neuronal tissues. The quantitative ratio between both series must be taken into consideration for an appropriate physiological balance [23]. This FA ratio is important because n-3 cannot be converted to an n-6 PUFA in humans, the n-3 content influences the n-6 concentration and vice-versa.…”

“…Therefore, the human capacity to synthesize the DHA can be inhibited by a high intake of n-6 LA. The balance between n-6 and n-3 PUFA in a diet is essential for the homeostasis, the normal growth and the development, because the eicosanoid metabolic products from n-6 and n-3 FAs exhibit opposing biological properties [6,20,23]. Most scientific studies on n-3 PUFAs in recent years aim at determining their immunological and anti-inflammatory effects, especially in cases of asthma, rheumatic arthritis and autoimmune diseases [20,23,24].…”

Evaluation of toxic metal levels in edible tissues of three wild captured freshwater fishes

“…Fishes are well known to be excellent dietary sources of essential fatty acids such as omega 3 polyunsaturated fatty acids (n-3 PUFA) [7].Fish respond sensitively to an increase of concentration of contaminants (metals, organic pollutants) in water. The accumulation level of metals in organs and tissues of fish depends upon taxonomic belonging of the fish species, age patterns, their physical-biochemical characteristics and chemical status of the environment they live [8].…”