Isolation and characterization of Arctic microorganisms decomposing bioplastics

Abstract

The increasing amount of plastic waste causes significant environmental pollution. In this study, screening of Arctic microorganisms which are able to degrade bioplastics was performed. In total, 313 microorganisms were isolated from 52 soil samples from the Arctic region (Spitsbergen). Among the isolated microorganisms, 121 (38.66%) showed biodegradation activity. The ability of clear zone formation on emulsified poly(butylene succinate-co-adipate) (PBSA) was observed for 116 microorganisms (95.87%), on poly(butylene succinate) (PBS) for 73 microorganisms (60.33%), and on poly(ɛ-caprolactone) (PCL) for 102 microorganisms (84.3%). Moreover, the growth of microorganisms on poly(lactic acid) (PLA) agar plates was observed for 56 microorganisms (46.28%). Based on the 16S rRNA sequence, 10 bacterial strains which showed the highest ability for biodegradation were identified as species belonging to Pseudomonas sp. and Rhodococcus sp. The isolated fungal strains were tested for polycaprolactone films and commercial corn and potato starch bags degradation under laboratory conditions. Strains 16G (based on the analysis of a partial 18S rRNA sequence, identified as Clonostachys rosea) and 16H (identified as Trichoderma sp.) showed the highest capability for biodegradation. A particularly high capability for biodegradation was observed for the strain Clonostachys rosea, which showed 100% degradation of starch films and 52.91% degradation of PCL films in a 30-day shake flask experiment. The main advantage of the microorganisms isolated from Arctic environment is the ability to grow at low temperature and efficient biodegradation under this condition. The data suggest that C. rosea can be used in natural and laboratory conditions for degradations of bioplastics.

Usage of Potential Micro-organisms for Degradation of Plastics

“…were found to have the highest degradation ability. The study further reported Colonostachys roseas as effi cient degrader causing 100% deterioration of starch fi lms within 16 days and 52.91% degradation of PCL fi lm within 30 days at 28˚C [5].…”

“…This time period allowed polymeric materials to step into every domain of human life [4]. A global estimate suggested plastics production up to three hundred and eleven million tons in 2014 [3,5] and reached up to three hundred and thirty fi ve million tons by 2015 which clearly depicts its enormously rapid production which will become twice in the next two decades whereas will reach nearly four-folds by 2050 [3].…”

“…In addition, the level of plastics has escalated six folds in the oceans compared to plankton which poses a serious threat to aquatic life [6]. It is estimated that about 1 million seabirds and 100 thousand marine mammals perish each year, where 44% of all seabirds, 86% of all sea turtles and 43% of all marine mammals and many fi sh are harmed by swallowing of plastic waste [5].…”

“…From the last 40 years, scientists are struggling hard to discover viable remedies to alter the destruction caused by plastics in the environment. Although the plastics have 300 million tons worldwide production each year [5], only a fraction of it is recycled. Various physicochemical factors and microbial communities in the environment are effi cient in breaking the resistance of polymers [8,15] besides its profound longevity.…”

Transforming Ocean Conservation: Applying the Genetic Rescue Toolkit

“…Recent research has identified Ideonella sakaiensis 201-F6 as an efficient biodegrader of PET plastics [42]. Additionally, a recent screen of microbial communities in the Arctic showed promise for plastic degradative abilities in Rhodococcus bacterial species and several fungal species [43].…”