Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Formaldehyde and dimethylamine in fishery products

Trimethylamine oxide (TMAO) is broken down to formaldehyde and dimethylamine by the enzyme TMAOase during the frozen storage of gadoid fish. The extraction (using detergents) and rapid measurement of the content of this enzyme in fish is, therefore, important and was one component of a major project. Work is also ongoing on the characterization of TMAOase in order to get the information necessary for the purification of the enzyme. In addition, its intracellular localization is being studied as is its activity in the tissues of saithe (Pollachius virens), hake (Merluccius merluccius) and whiting (Merlangus merlangus). Some of the findings are as follows. A fast and reliable test system for TMOase has been established based on the reaction of the generated formaldehyde with NAD (nicotinamide dinucleotide) to produce reduced nicotinamide adenine dinucleotide (NADH) which is measured spectrophotometrically, or by a microplate reader. A simple low cost test system has also been developed where the formaldehyde is determined using a test strip. A very high TMOase activity was found in the kidney, spleen and stomach wall of cod, saithe and whiting. These tissues were also used to determine the intracellular (within cells) localization of TMOase activity. This was highest in the lysosomal and mitochondrial fractions. These data are of significance for the determination of the quality and shelf life of fish and will be of major use to fish processors and distributors.

Reported by

Federal Research Centre for Fisheries
Palmaille 9
22767 Hamburg
Germany
See on map