Experimental Substantiation of Feasibility of Using Enzymatic Fibrin Hydrolyzate-Based Medium to Obtain Components of Chemical Cholera Vaccine

Abstract

The aim of the study was to experimentally substantiate the possibility of using a nutrient medium based on enzymatic fibrin hydrolyzate in order to obtain specific components of chemical cholera vaccine: cholerogen-anatoxin and O-antigen. Materials and methods. We used production strains of Vibrio cholerae 569B and V. cholerae M-41. Submerged low-volume cultivation was carried out in a laboratory fermenter for 8 hours, with automatic maintenance of cultivation parameters and feeding with glucose on the nutrient medium based on enzymatic fibrin hydrolyzate, containing (1.0±0.1) g/l of amine nitrogen, pH being (8.0±0.1). Cholerogen-anatoxin and O-antigens were obtained from detoxified formalin-treated centrifugates of culture liquids. The specific activity of V. cholerae antigens at the stages of cultivation and isolation was determined applying immunochemical methods. The preparation of the finished dosage form of the cholera vaccine and the coating of the tablets with an enteric coating was carried out in accordance with the regulatory documentation. Results and discussion. It has been shown that cultivation on the medium based on enzymatic fibrin hydrolyzate provides a stable growth of the biomass of V. cholerae production strains with a high level of specific activity of antigens. Comparative analysis of the main properties of the finished dosage form of laboratory batches with a commercial batch of chemical cholera vaccine has demonstrated compliance with the requirements of regulatory documentation. The results obtained has led us to conclusion that it is feasible to use the nutrient medium based on enzymatic fibrin hydrolyzate for cultivating production strains and obtaining specific components of the cholera vaccine.