STUDY ON LOCALIZATION OF DEGRADATION ENZYME FOR NHEXADECANEAND ENZYMATIC DEGRADABILITY

摘要

Petroleum hydrocarbons cause serious environmental problems. However, the mechanism of degradation byrnmicroorganism was partially unknown. Localization of degradation enzyme in two bacteria for n-Hexadecane, production andrncharacteristics of n-Hexadecane-degrading enzyme were studied in this paper. The cellular extracts of l bacterium were fractionatedrninto extracellular, periplasmic and cytoplasmic fractions after osmotic shock. The results showed that the main enzyme, in the 1rnbacterium, which are cytoplasmic and membrane-associated enzymes, decomposed mainly n-Hexadecane. And most of the enzymernactivities (both 100%) in 2 bacterium were detected in the cytoplasmic and extracellular extracts. Moreover, culture conditions have arnsignificant effect on the enzyme activity produced in hexadecane cultures of 1 bacterium and 2 bacterium, and the optimum of thernconcentrations of hexadecane is 10mg/L.The rhamnolipid(2mM) was the most effective in stimulating producing the main enzyme ofrndegradation for n-Hexadecane. The enzyme is active when the pH value is in the range of 7.0~8.0, and the most suitable pH value isrnnear 7.0. The enzyme is active at temperatures up to 30℃, but it is instable at higher temperatures.