Plastics accumulate in the environment and gradually break into microplastics (MPs, size below 5 mm). It poses a serious threat to the environment and human health. In this study, a strain LC-2 capable of degrading polyethylene (PE) was isolated from plastic films collected from the Licun Estuary of Qingdao. It was identified as Bacillus aquimaris by using a combination of molecular biological technique with morphological, physiological and biochemical characteristics. After the strain was isolated, it was cultured in a liquid medium for 28 days with PE as the sole carbon source. The polyethylene was subsequently separated and examined with a scanning electron microscopy, a contact angle test, a thermogravimetric analysis and a Fourier transform infrared spectrum analysis. The results showed that the weight loss of PE was about 9% after the degradation, with apparent morphologic changes on the surface of PE. It was also showed that the hydrophobicity of PE became smaller, with surface oxidation to produce −C=O functional groups. These evidences are sufficient to prove that the strain LC-2 can degrade PE.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |