Development of the technology for preparation of enzymatic hydrolysate of waste chick embryos

The development of technologies for preparation of protein nutritional bases for microbiological nutrient media, from production waste of mainly readily available or non-food products, is a promising area in biotechnology. Researchers of Vyatka State Agrotechnological University assume that non-food secondary raw materials, such as waste chick embryos (WCEs) used in the production of anti-influenza products, could be used for these purposes, after removal of the virus-containing allantoic fluid. The aim of the study was to develop a technology for preparation of WCE enzymatic hydrolysate (WCEEH), and to evaluate growth properties of the hydrolysate-based solid nutrient medium, using Escherichia coli M-17 and Pseudomonas alcaligenes IP-1 test strains. Materials and methods: the authors offer methodological approaches to obtaining WCEEH and substantiate hydrolysis parameters. The obtained WCEEH was characterised in terms of physico-chemical properties: pH, amine nitrogen, total nitrogen, sodium chloride, degree of protein cleavage. The growth properties of the hydrolysate-based nutrient medium were studied using E. coli M-17 and Ps. alcaligenes IP-1 test strains. Results: the experiments demonstrated the feasibility of performing enzymatic hydrolysis of WCEs, and assessed physico-chemical properties of the prepared WCEEH batches. The study demonstrated the possibility of using the prepared hydrolysate as a component of solid nutrient media for growing the selected test strains. Conclusions: the study substantiated the optimal technological parameters for WCE enzymatic hydrolysis: pH (7.6 ± 0.3), duration (48 ± 2 h), temperature (49 ± 1) °C. The loading of hydrolysis components was optimised: mass fraction of the substrate—500 g/L, mass fraction of the hydrolysing agent—100 g/L. The physico-chemical properties of WCEEH make it suitable for preparation of microbiological media; the hydrolysate-based solid nutrient medium consistently ensures the growth of E. coli M-17 and Ps. alcaligenes IP-1 test strains with standard properties. The growth properties of the experimental medium are comparable to those of the meat-peptone broth-based nutrient medium.

Evaluation of the effect of enzymatic hydrolyzate of the bursa of broiler chickens on cytotoxic activity and nonspecific immunity

The use of biologically active substances of tissue origin for the creation of biologically active additives and immunomodulatory drugs is an important area of scientific research in the field of nutrition and pharmacology. The aim of the work is to evaluate the effect of enzymatic hydrolysate from the fabricium bag of broiler chickens on the cytotoxicity and nonspecific immunity of mice against the background of experimental salmonella infection using biotechnological methods. For the experiment, three equal experimental groups of white mongrel mice were formed. All laboratory animals were fed daily for seven days with enzymatic hydrolysate at a dose of 750 mg/kg (therapeutic dose), 150 mg/kg (0.2 therapeutic dose) and 3,750 mg/kg (five therapeutic doses). At the same time, the control group of animals received intragastric water in the same volume. 24 hours after the last intake of the enzymatic hydrolysate, the animals were intraperitoneally infected with a culture of Salmonella enteritidis 92. The study reveals the absence of cytotoxic properties and impaired cell viability in cultures L929, J774.1A, HeLa S3, K562, and HST116 against the background of exposure to various concentrations of enzymatic hydrolysate from 0.02 to 10 mg/ml. It should be noted that there is a pronounced cytotoxic effect on MCF-7 tumor cells of the concentration of enzymatic hydrolysate in culture of 5 and 10 mg/ml, which suggests the possibility of using enzymatic hydrolysate for the prevention of tumor diseases. As a result of the experiment, it has been proved that the administration of enzymatic hydrolysate to mice increased the LD50 index and the survival rate of mice infected with the culture of the causative agent of salmonellosis by 1.5 times. Based on the conducted studies, it has been shown that the enzymatic hydrolysate of the lymphoid tissue of broiler chickens does not violate the viability of mammalian cells and does not exhibit cytotoxic properties on the metabolism of healthy mammalian cells, which indicates its safety. In an experiment on mice, the effect of enzymatic hydrolysate of the fabricium bag of broiler chickens on the activation of nonspecific immunity against salmonella infection has been revealed.