Research On The Effect Of Compound White-rot Fungi On The Laccase Production And The Degradation To Phenanthrene

In developing countries, human vigorously develop industries to promote economic development rapid and meet their own needs. There will be a lot of substances which are toxic and hazardous during the production process of industrial, and the substances can not be adequately degradation, because of the technological backwardness, but being discharged into the environment directly. So the environment has suffered serious pollution and damage. Polycyclic aromatic hydrocarbons (PAHs) are persistent toxic organics, and have the characters of carcinogens, teratogens and mutagens. Microbial degradation, one of the methods to degrade PAHs, is high efficiency, low cost, degradation thorough, and becomes a hotspot of research. The factors of microbial species and inoculation amount have a huge impact on the rate of degradation of PAHs, and there is not research on those factors so far.Based on the preliminary studies of the seminar, the relationship of three different kinds of white-rot fungi is studied by experiment. The white-rot fungi are Polyporellus picipes, Pleurotus ostreatus and Pseudotrametes gibbosa, respectively. We compound with any two kinds of white-rot fungi and change the inoculation ratio of the two white-rot fungi. And the optimum inoculation ratio of the two white-rot fungi is confirmed according to the yield of the laccase and biomass. Experimental studies have shown the optimum inoculation ratio of the Polyporellus picipes and Pseudotrametes gibbosa is2:1, then the enzyme activity is47.19U/mL, and the biomass is0.11g. The optimum inoculation ratio of the Pseudotrametes gibbosa and Pleurotus ostreatus is1:1, then the enzyme activity is27.9U/mL, and the biomass is0.0.77g. After analyzing the relationship of output of the laccase between biomass of the two sets of optimal biomass, we find that the growth of the complex bacteria is positive correlation with the yield of the laccase.The degradation rate of the two sets of optimal complex bacteria to the phenanthrene is investigated, and the effects of phenanthrene on the growth of optimal complex bacteria and the yield of laccase are studied. On the25th day, Experimental results show that the degradation rate of optimal complex bacteria of Polyporellus picipes and Pseudotrametes gibbosa to phenanthrene is78.21%; the degradation rate of optimal complex bacteria of the Pseudotrametes gibbosa and Pleurotus ostreatus to phenanthrene is46%. The growth of the two sets of optimal complex bacteria is promoted by the substrates of phenanthrene. And the yield of laccase is increased also by the substrates of phenanthrene.