OBTAINING AND CHARACTERISTICS OF CALCIUM ORGANIC FORMS ON THE BASIS OF METABOLITES AND PROCESSING PRODUCTS OF PROBIOTIC BACTERIA

The possibility of obtaining bioavailable mixed ligand chelate complexes of calcium has been considered. As bioligands, it is proposed to use the metabolic products of probiotic bacteria combination and products of enzymatic hydrolysis of peptidoglycans of their cell walls. The culture fluid of probiotic bacteria composition has been investigated for the determination of metabolites in its composition that can participate in the formation of calcium chelate complexes. The qualitative composition and quantitative content of organic acids of a culture fluid have been determined. It has been established that it contains the following acids: oxalic (1.6 mg/dm3), citric (22.1 mg/dm3), acetic (575.8 mg/dm3), lactic (236.3 mg/dm3), benzoic (1.5 mg/dm3). In addition, it has been found that in the composition of the culture liquid, free amino acids and soluble protein are also present in the amount of 1.2 mg/cm3 and 5 mg/cm3, respectively.In order to obtain fragments of peptidoglycans of cell walls of probiotic bacteria as potential bioligands for complex formation, their enzymatic hydrolysis with pancreatin has been performed. It has been established that the highest content of biologically active muropeptides is 5.1 mg/cm3 and it is accumulated during hydrolysis of the substrate for 180 minutes, the ratio of enzyme: substrate 1: 100 and 5.1 mg/cm3.By methods of nephelometry and spectrophotometry, it has been established that the obtained mixed ligand systems are effective chelating agents and, depending on the composition, bind calcium in amounts of 9, 14 and 16 mg/cm3. Identification of the pH stability of the complex has been shown that in the range of pH values 4–7, the chelate system is stable, at pH 2 only 10% of the complex is stored, at pH 9 60% is preserved. By method of differential scanning calorimetry the thermostability of the complex has been investigated. It has been established that the complex is stable in the temperature range of 20–122°С, and therefore can be used in the composition of health foods, the technology of which involves high-temperature processing.