Title: Microbiology of biodegradation with selected biodegradable polymers in soil
Abstract:
Plastic leaking into the environment represents one of the major environmental concerns nowadays. Part of the solution is the replacement of conventional plastics with suitable biodegradable polymers. This especially useful in application where the items cannot be easily retrieved from the environment for example in agriculture. Here the biodegradation of the polymer items is expected to take place in soil, and it is of interest what mechanism and what microorganisms take place in the process. Such knowledge can be useful for further rational design of future polymer materials. Microorganisms related to biodegradation of PBAT, PHB and PBS biodegradable polymers were investigated in soil. All mentioned polymers are essentially polyesters but still they differ substantially in their properties which is also translated into differences in the rates of their biodegradation in soil. DNA form the surface of the material was isolated in appropriate time intervals and 16r and 18r RNA genes were amplified and sequenced. Data were further processed to assign abundance and taxonomic categories to individual OTUs. Composition and dynamic of microbial communities for individual materials were observed and compared, especially the participation of bacteria and fungi part of microbial community on the biodegradation process was estimated. Results show that different polymers need slightly different microbial groups for their biodegradation especially in relation to the rate of their biodegradation in soil. Roughly this can be described as a difference between slow and fast degrading polymers. The finding is of interest for certain applications where the polymer product must withstand certain time period in the biotic environment, e.g. in soil, without actual biodeterioration before the biodegradation process is welcomed.
