Degradation Of Polyethylene By Microbacterium Sp.4-7

Polyethylene(PE) is one of the main source of ‘white pollution’. So, it’s of great significance that PE is degraded in a green and economic way.Bacterium 4-7 was screened from landfills, which can use PE as the sole carbon source. This strain was identified and named as Microbacterium sp. 4-7. by comparing the 16 S r RNA in Ez TAxon database. Microbacterium sp. 4-7 was growing slowly. The stationary phase was after 60 hours. The surface of PE degraded with Microbacterium sp. 4-7 became uneven by scanning electron microscopy(SEM). The amount of Microbacterium sp. 4-7 in CDM medium containing PE became twice bigger than that in CDM medium without PE after nine months. It showed that PE can promote Microbacterium sp. 4-7 growing.The IR spectrum of PE embedded in the sandy soil containing Microbacterium sp. 4-7 appeared a new functional groups at 1818 cm-1, while it did not appear in the soil without Microbacterium sp. 4-7. It suggested that Microbacterium sp. 4-7 could degrade PE. After UV irradiated, PE would generate a carbonyl peak at 1750 cm-1. Microbacterium sp. 4-7 and soil microbes could degrade the UV-PE. There was a 4.35% reduction of the UV-PE in soil with Microbacterium sp. 4-7 in it. And it created a new peak at 1818 cm–1. Carbonyl had already been used by microbes. The amount of PE degradation was less than UV-PE. It means that it was easier to bio-degrade PE after UV treatment.This study has screened a unreported PE bio-degradation strains. It has opened up a new way for PE green degradation.