Published: 2018-07-24

Black Sea fish and shellfish as essential source of vitamin B12

Diana A. Dobreva, Albena V. Merdzhanova, Mona D. Stancheva, Doychin I. Terziyski, Veselina Z. Panayotova


Background: Vitamins are very important for the human body because they are necessary for many biological absorption processes of other nutrients, for cells and tissues growth and repair. Because of this, there are many recommendations on daily vitamins intake, approved by the different country and world food organizations. Usually under the term "vitamin B12" is understood only cyanocobalamin, but actually this name is general and covers all potentially biologically active "cobalamins"- a group of cobalt-containing compounds. Animal foods, as different meat, milk, eggs, fish and shellfish are considered as the main dietary sources of this vitamin. They contain different forms (methylcobalamin and deoxyadenosylcobalamin) of vitamin B12 in different amounts. There is limited information in the scientific literature about the vitamin B12 content in black sea fish and shellfish. The aims of the present work were to determine and compare vitamin B12 contents as well as relative daily intake of vitamins in different fish and shellfish species from Black Sea waters.

Methods: Vitamin B12 was analysed spectrophotometrically. The method for quantitative analysis includes extraction from the edible tissue and enzymatic hydrolysis to release the cobalt ions.  

Results: The quantities of vitamin B12 found in the edible tissue of the analysed samples ranged from 0.63 μg.100 g-1 ww to 21.5 μg.100 g-1 ww.

Conclusions: The observed results confirm that all fish and molluscs samples deliver significant quantities of the water-soluble vitamin B12.



Cyanocobalamin, UV-Vis, Spectrometry, Cobalt-complexes, Mussel

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