Effect of calcium propionate on rats with a high-fat hypercaloric diet

Calcium propionate, as an approved food additive, is widely used as a mold inhibitor in food and feed. It is recognized as safe, but when metabolized in the gastrointestinal tract, it can affect the body's metabolism both directly and indirectly through the intestinal microbiota. The effect of various doses of calcium propionate on the body of model animals, with the study of the quantitative and qualitative composition of their intestinal microbiome, was investigated in this experiment. Four groups of male laboratory rats were formed, which for 20 days consumed: a high-fat diet with the addition of 0.0%, 0.5%, 1.0%, 2.0% calcium propionoate. We determined changes in body weight, the condition and mass indices of the internal organs, biochemical blood parameters, the functional state of the nervous system using the "open field" method, as well as changes in the intestinal microbiota. Adding calcium propionate to a high-fat diet does not affect the rate of animals' weight gain, nor the amount of feed and water consumed. High dose consumption of calcium propionate caused a decrease in the relative weight of the spleen and an increase in the relative weight of the kidneys, without affecting the functional state of the nervous system. With the addition of calcium propionate to a high-fat diet, only minor changes in some biochemical blood parameters were observed (increased De Ritis ratio and Ca/P ratio, moderate dyslipidemia). Calcium propionate had the most significant changes in the quantitative and qualitative composition of the intestinal microbiota in laboratory rats. Among the representatives of the microflora, the most sensitive to this substance against the background of a high-fat diet were obligate microorganisms from the genera Bifidobacterium and Lactobacillus. The antimicrobial action of calcium propionate was also demonstrated by the pathogenic Staphylococcus aureus. Amid a deficiency of obligate microflora, proliferation of transient microflora was found - facultative anaerobic and aerobic microorganisms (bacteria of the genera Klebsiella, Enterococcus, Clostridium, fungi of the genus Candida). Further research will be aimed at studying the effect of calcium propionate in various doses on the biological systems of different age group laboratory animals in a long-term experiment.