Keyword: «bacteria»

Research and evaluation of biostability of polymeric composite materials to natural factors, such as microorganisms: mold fungi, bacteria, actinomycetes. Study of species diversity of biodegraders and methods of their identification.

The microorganisms that cause biocontamination and bio-damage of experimental samples of polymeric composite materials exposed at the open range of climatic tests in Yakutsk were isolated. The landscape of isolated microorganisms is dominated by spore-forming bacteria p. Bacillus and mold fungi p. Aspergillus, Penicillium, Mucor; occurs: Rhizopus, Chetomium, Scopulariopsis, Fusarium, Trichoderma, etc. It was shown that bacteria (mostly spore-forming) are better adapted to the polymeric substrate and pass from the spore to vegetative stage faster than mold fungi. The microorganisms isolated during the tests can serve as the basis for creating models of microbial consortia, as fungicidal additives to polymeric compositions that can be used to develop polymeric composites adapted to northern conditions.

The article examines the biodegradation of polymer composites (glass, carbon, and basalt plastics) by bacteria, mold fungi, and their consortia at various temperatures, humidity, and exposure time. The biological contamination was assessed using microscopy, and structural changes were revealed: the formation of new functional groups and the cleavage of polymer chains caused by climatic aging and biodegradation.

Using experimental fiberglass laminate specimens as an example, the ability of microorganisms (bacteria and filamentous fungi) to participate in the contamination of polymer composites is demonstrated. Filamentous fungi of the genera Aspergillus, Rhizopus, and Penicillium, as well as three species of spore-forming bacteria of the genus Bacillus capable of causing biodeterioration of composite materials, were isolated from the fiberglass specimens. It is shown that the Bacillus subtilis strain exhibits biocidal properties, which is promising for further study as a biotechnology object.