| 摘要 |
FIELD: biotechnology, medicine. SUBSTANCE: Lingud broth is purified by ultrafiltration on diaphragms at retention limit value 20 kDa, not less. Then the obtained permeate is subjected for heat or cold sterilization by microfiltration on diaphragms at pore diameter 0.45 nm, not above (if medium will be used immediately) or 0.22 nm, not above (for medium storage). Sowing material of diphtheric corynebacteria strain is added to the purified broth and cultivation is carried out under aeration and stirring under toxin formation control followed by toxin separation from the cultural fluid. After ultrafiltration heterogeneity of nutrient medium is decreased, high-molecular inhibitors of toxin formation were removed. Change of heat sterilization for microfiltration allows to retain growth factors and vitamins in medium that are destructed partially at heat sterilization. Method provides the preparing diphtheric toxins with high titers. EFFECT: improved method and quality of toxin, nutrient medium preparing. 3 ex |
