Microbial Degradation of Polyethylene Glycol

Polyethylene Glycol의 미생물학적 분해

The bacteria capable of utilizing polyethylene glycol(PEG) 6,000 as a sole carbon source were isolated from soil and sewage water connected to factory area. The isolate designated as EL-033 had high biodegradability on PEG 6,000, and was identified as Micrococcus sp. Micrococcus sp. EL-033 could grow on and degrade di-, tri-, tetraethylene glycols and PEGs with molecular weight up to 6,000 and very slowly stilize PEG 20,000 as sole carbon source, but not degrade ethylene glycol. The growth rate of isolate was increased in the higher molecular weight PEGs. The optical culture medium was established to be as follow: PEG 6,000, 0.2%(w/v); $K_2HPO_4$, 0.1%; $NaH_2PO_4{\cdot}12H_2O,\;0.1%\;:\;MgSO_4{\cdot}7H_2O$, 0.05%; polypeptone, 0.1% in distilled water, pH7.5. About 90% of PEG 6,000 was degraded in exponential phase of 48h culture and PEG 6,000 was completely degraded during 72h.

PEG 6,000을 유일한 탄소원으로 이용할 수 있는 세균을 하천수와 하천부끔의 토양으로부터 분리하였으며 이증 분해능이 우수한 EL-033 isolate-를 Micrococcus sp. 로 동정하였다, Micrococcus sp. EL-033은 mono-ethylene g glycol플 세외한 di-, tri-, tetra-ethylene glycol파 분자량 6,000까지의 PEG닫을 분해하였으며 그 중합도가 높윤 수복 생 앙상태까 좋은 분해특성을 가AI고 있였으며. PEG 20, 000에 대해서도 약간의 분해능음 가지고 있었다. 최적 배지 조성은 PEG 6,000 0.2% $K_2HPO_4$, 0.1% $NaH_2PO_4{\cdot}12H_2O0.1%MgSO_4{\cdot}7H_2O$0,1 %, polypeptone 0,1 %, $MgSO_4$, 0,05 % (pH7,5) 이었다. 생장 최적조건에서 PEG 6,000의 분해는 대수증식기인 48시간 배양하였을때 90%이상의 분 해융플 나타내있으며,72시간 후에 거의 완전히 분해되었다.