ORIGINAL RESEARCH
Development of microbial preparation for bioremediation of soils contaminated with rocket fuel components
1 Research Center for Toxicology and Hygienic Regulation of Biopreparations of the Federal Medical Biological Agency, Bolshevik, Moscow region, Russia
2 National Research Center Institute of Immunology of the Federal Medical Biological Agency, Moscow, Russia
Correspondence should be addressed: Gennady A. Zharikov
Lenina, 102А, Bolshevik, Serpukhov city district, Moscow region, 142253, Russia; ur.oibcixot@vokirahZ
Funding: the study was carried out under state orders of the Federal Medical Biological Agency of Russia (№ 26.008.02.0, № 22.009.21.800).
Author contribution: Khaitov MR — general research management; Zharikov GA — planning and management of laboratory and field research, experimental procedure, data analysis; Krainova OA — microbiological testing (isolation and selection of bacterial destructors of rocket fuel, preparation of microbial suspensions for experiments, biodestructor collection maintenance); Marchenko AI — microbiological and biochemical testing (enzyme activity of soil), biotests for assessment of soil toxicity, statistical data processing.
Compliance with ethical standards: animals were treated in accordance with the principles of Good Laboratory Practice. Veterinary protocols № 669 and № 677 for strains 5G и 62М/3 were approved by the Bioethics Commission (protocol № 165/2019 of 19 February 2019, protocol № 169/2019 of 16 April 2019).
Heptyl rocket fuel and aviation kerosene are widely used in the propulsion systems of the Proton and Soyuz spacecraft. The propellant components (RFC) enter the environment, causing strong toxic effects, when the separating first stages of rockets fall away or in case of emergencies. The study was aimed to isolate strains of microorganisms-destructors of RFC, as well as to assess their safety for bioremediation of contaminated soils. Microorganisms capable of decomposing heptyl, formalin, and aviation kerosene were isolated from natural soils. An association of two strains of bacterial destructors Pseudomonas putida 5G and Rhodococcus erythropolis 62М/3 was obtained, and a method of their use in recultivation of soil contaminated with RFC was developed. The results of laboratory and field tests showed high efficiency of the microbial destruction of pollutants, the decrease in integral toxicity and phytotoxicity of the cleaned soil to safe levels, and an increase in the soil biological activity. Thus, dehydrogenase activity increased by 2.4 times, hydrolase activity by 2.1 times, and cellulase activity by 5.1 times. Microbial association can be recommended for recultivation of soil contaminated with RFC.
Keywords: rocket fuel, heptyl, dimethylhydrazine, formaldehyde, aviation kerosene, rocket fuel components, degrading microorganisms, soil bioremediation