Isolation and characterization of microorganisms from contaminated environments and their potential application in plastic biodegradation

DENARO, MARIA AZUL; LACAVA, JUDITH ELIZABETH; FERNANDEZ M A; BERNABEU, PAMELA ROMINA

lOS cOCOS, cORDOBA

Congreso; XVII Congreso Argentino de Microbiología General; 2022

Asociacion civil de Microbiologia General

Plastic is a synthetic or semi-synthetic organic polymer derived from petroleum. Commonly used methods for the disposal of plastics are inadequate for effective plasticwaste management and, therefore, there is a growing interest in the use of efficient microorganisms for its biodegradation. In the present work, the isolation ofmicroorganisms from environmental samples of water and sediment from the Río de la Plata and the Paraná River Delta was carried out. We were able to isolate 73apparently different microorganisms, a number that after morphological and biochemical analysis has been reduced to 58 isolates. The biofilm-forming capacity of thesemicroorganisms was analyzed using the Crystal Violet staining technique. The 5 best isolates were selected for further testing. With these isolates, polypropylene pelletdegradation assays were performed, initially growing the microorganisms in minimal culture medium and decreasing the glucose concentration until reaching the growthcondition in polypropylene as the only carbon source. These cultures were monitored for 40 days, performing bacterial plate counts every 10 days. 3 isolates were able togrow with plastic as the only carbon source. Degradation was analyzed by measuring the initial and final dry weight of the plastics in the cultures, having observed that therewas only a decrease in the dry weight of plastic in the cultures whose microorganisms were able to grow. Finally, plastics were observed by Scanning Electron Microscopy(SEM), which allowed us to corroborate the previous results.