Antimicrobial Properties of Water-Soluble Polysaccharides and Alcoholic Extracts of Laetiporus Sulphureus (Bull.) Murrill Mycelium and Development of Biotechnology for Its Production in Immobilized Culture on Bacterial Cellulose

The article discusses the development of a new method of producing Laetiporus sulphureus (Bull.) Murrill basidiomycete mycelium immobilized on a bacterial cellulose matrix. Mycelium contains biologically active compounds with antimicrobial activity against Gram-positive bacteria, including resistant staphylococcus. The aim of the work was to obtain immobilized mycelium by co-cultivation of L.sulphureus with the producer of bacterial cellulose Gluconacetobacter hansenii. The authors found that when co-culturing the basidial L.sulphureus strain with the bacterial cellulose producing G.hansenii strain, productivity increases by 3.2 times on H5/1 synthetic medium and by 1.9 times on natural Maltax-10 medium (concentration 5%). The resulting immobilized L.sulphureus mycelium has antibacterial properties; its aqueous extracts contain glucans.

Immobilization of Rhodococcus wratislaviensis Strain KT112-7 Сells in Order to Increase Efficiency of Biodegradation of Modified Polychlorinated Biphenyls

The degradation of a mixture of hydroxy- and methoxy-PCB obtained as a result of a chemical modification of a commercial mixture of PCB «Sovol» by the Rhodococcus wratislaviensis strain KT112-7 in plankton culture or immobilized on carbon carriers has been investigated. It was established that the KT112-7 strain in plankton culture degraded 73.2% of a mixture of modified PCBs for 96 h; the strain immobilized on BAU-A activated carbon and on Carbopon-B-active carbon fiber provided the 59.5% and 95.3% degradation for the same time, respectively (with the starting concentration of PBS of 0.5 g/L). The application of the R. wratislaviensis KT112-7 strain immobilized on the BAU-A carrier decreased the number of the PCB derivatives by 1.5 times at the end of the experiment; the corresponding result for the Carbopon-B-active-immobilized culture was 3 times; the set of PCBs after the treatment with the suspension culture remained unchanged. In practice, the immobilization of R. wratislaviensis КТ112-7 strain on carbon carriers can be used in the development of the techniques for the degradation of chemically modified PCB mixtures. polychlorinated biphenyls, immobilization, destruction, utilization, PCB, Rhodococcus. Funding-This work was supported by the Integrated Program of the Ural Branch of the Russian Academy of Sciences No. 18-3-8-19. The work was performed using the equipment of the Center for collective use «Spectroscopy and analysis of organic compounds».