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

Abstract

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.

Keywords

• technology
• chick embryos
• non-food raw materials
• growth medium
• enzymatic hydrolysate
• enzymatic hydrolysis