Obtaining radioactivated strains of microorganisms and studying their antiradiation efficiency

Abstract

The preparations of microbial origin inactivated by irradiation on the “Researcher” gamma device were used as potential antiradiation drugs: E. coli strain “KV-1”, “PL-6”. The preparations were obtained by growing cultures in mesopatamia broth in a thermostat at 37 °C for 3 days, then centrifuged at 3000 rpm for 40-50 min, the supernatant was decanted, the precipitate was diluted with distilled water according to the L.A. turbidity standard. … Tarasevich up to 1 billion / ml. From the grown cultures, smears were prepared and stained according to Gram to determine the purity and species of the grown culture. The prepared suspension was poured into sterile vials of 10, 50, and 100 ml each, sealed with rubber stoppers and rolled in with aluminium caps, marking with the indication of the strain, radiation dose and date. Irradiation of microbial material was carried out on a gamma device “Researcher”, a source of 60Co, exposure dose rate 3.7 kGy / h, in the range of absorbed doses from 7.5 to 30 kGy with inter-dose intervals of 2.5 and 5 kGy. Studies to determine the radioprotective effectiveness of strains of microorganisms killed by gamma-irradiation were carried out on outbred sexually mature white mice with a live weight of 18-20 g, divided according to the principle of analogues into groups of 5 animals each according to the following scheme: irradiation + E. coli strain “KB- 1”, irradiation + E. coli strain “PL-6”, control of irradiation, biological control. Acute radiation sickness was simulated using the Puma gamma device with a 137Cs radioactive source at a dose of LD80-100 / 30. The test preparations were injected subcutaneously in a volume of 0.2 cm3 three days after radiation exposure. It was found that the introduction of cultures of microorganisms inactivated by gamma-irradiation E. coli strain “KV-1”, E. coli strain “PL-6” 3 days after external radiation exposure contributed to the preservation of 60 to 80% of irradiated white mice.