The aim of this paper is to give an overview of the presence of biogenic amines, particularly histamine, in various food products, discuss the most important factors influencing their accumulation, and address potential toxicity and safe limits in food. Biogenic amines are natural components of animal and plant raw materials, where they are present at concentrations appearing non-harmful to human health. Their increased content in foods results from the activity of endogenous enzymes or from the microbial decarboxylation of amino acids during controlled or spontaneous fermentation, processing, storage, and distribution. General knowledge of biogenic amines, factors favouring their formation and their safe limits in food are useful in preventing exposure to their toxic effects on the human body. Based on this information, appropriate prophylaxis can be applied, which will consist primarily of maintenance of good hygiene standards of raw materials and products, employment of appropriate processing procedures and upkeep of sanitary food storage conditions.

Salted fish is a common food type in Egypt that is consumed in certain occasions and celebrations. The manufacture process of the salted fish allows fermentation of different fish species. Therefore, there is a high chance for microbial growth and multiplication on such rich protein substrate, and decomposition of the amino acids to their biogenic amines (BAs) derivatives. This study was undertaken to estimate the formed BAs in three salted fish retailed in Egypt, named feseikh, sahlia, and salted sardine. In addition, microbial counts including total plate counts (TPC), total psychrophilic counts (TPsC), and total Staphylococcus aureus counts (TSC) were enumerated. Dietary intakes and health risks associated with the formed BAs were also calculated and discussed. The obtained results revealed formation of the BAs in all examined salted fish species. Feseikh had the highest BAs contents as well as microbial counts. In conclusion, although the calculated dietary intakes revealed no potential risks associated with the consumption of the salted fish, however this assumption should be handled carefully due to inter-individual differences in their immune-reactions to such BAs, particularly histamine.

In this study, the detection of biogenic amines in fresh and products of fish is focused and biological trials have been used to reduce their levels. 120 random samples of fresh fish (Lates niloticus), sardine salted, herring smoked, and tuna canned (for every thirty samples) were collected from different markets in Shibine, Menoufia, Egypt. The biogenic amine residues have examined in all samples that were collected (histamine, putrescine, cadaverine and tyramine). The average levels of biogenic amines in the samples under investigation of fresh fish, canned tuna, herring smoked, and sardine salted are 10.74 ± 0.54, 15.08 ± 0.76, 17.93 ± 0.81 and 26.12 ± 0.89 mg % for histamine, 7.61 ± 0.49, 11.13 ± 0.57, 14.35 ± 0.64 and 19.59 ± 0.81 mg% for putrescine, 5.96 ± 0.43, 10.22 ± 0.49, 12.41 ± 0.58 and 16.85 ± 0.62 mg% for cadaverine each, accordingly. Finally, the tyramine mean value was 2.05 ± 0.10 mg % in fresh fish, 6.37 ± 0.19 mg % in tuna canned, 7.9 ± 0.24mg % for herring smoked and10.44 ± 0.27 mg % for sardine salted. Fish fillets were experimentally inoculated with B. polymyxa culture (2x107), the effect was ideal, the level of histamine reduced to 31.4 mg/kg after eight hours, 19.5 mg/kg after 12 hrs and 12.8 mg/kg 24 hours later with reduction percentages of 37.2%, 61.0%, and 74.4%, respectively and cadaverine level reduced to 22.1 mg/kg after 8 hours, 15.4 mg/kg after 12 hrs and 9.7 mg/kg 24 hrs later with reductions percentages were 26.3%, 48.7%, and 67.7%, respectively.

In animal feeding technology much attention is given to application of biologically active substances for metabolism stimulation. One of such biologically active substances is carnitine, an anabolic preparation of nonhormonal nature, cofactor in system of oxidation of fat acids. It participates in processes of acetylation at oxidation of fat acids together with acyl-CoA and other enzymes, promotes carrying over of cytoplasmatic Coa-derivatives of fat acids inside mitochondrions. It increases absorption speed from a digestive path of nutrients of forage, raises use of fat acids for the power purposes. Under its influence synthesis of triglycerides decreases and synthesis of phospho-lipids increases. Carnitine also protects cells against toxic accumulation of components of acyl-CoA of endogenic or exogenous origins, such as acylic groups of carnitine ethers which then can pass into liver for dissimilation or in kidneys for allocation in urine. Carnitine synthesis satisfies body requirements, but in the conditions of a hightened stress, high productivity, as well as in the conditions of lowered carnitine content in forage or in the conditions of the increased content of fats it should be applied as additive to diet. As a result of the realized study it was established, that the optimal quantity of carnitine application in diets for stores husbandry and fattening is dose of 50 g/t of mixed fodders. Application of carnitine in an optimum dose renders the positive impact on animal organism, promotes the increasing average daily weight gain on 5,1% (Р less than 0,001). Application of carnitine in diets of swine stores increases a slaughter yield on 2,1%, meat content per carcass - on 2,3%, a loin eye area - on 8,8%. Carnitine application in a dose 50 g/t of mixed fodders makes it possible to receive the additional profit at a rate of 4,57 USD per 1 head