摘要
采用室内培养试验方法,在芘降解试验中引入一株白腐真菌———黄胞原毛平革菌,通过优化培养条件,成功地将白腐真菌和芽孢杆菌进行了混合扩大培养。结果表明,该方法大大提高了降解性能,最终芘的去除率高达99.5%,除去菌体吸附,芘的同化吸收率也高达90%,同时大大降低了芘的残留阈值,从12%降低到0.5%,降低了芘在环境中的生态风险。本文研究了关键中间代谢产物1-羟基-2-萘酸(1H2N)及其等价物的积累与利用情况,混合菌产生的1H2N等价物最大浓度为5.16m g·L-1,为其理论产量的110.9%,这进一步证明了芘的降解途径首先是生成多酚化合物。
Two Bacillus sp. have been tamed and isolated from an aged PAHs contaminated soil at previous research in our lab. It has been proven that they areboth pyrene degrading bacteria. The degradation of PAHs by white rot fungi has been extensively examined in experiments both using liquid culture and in situ. In this study, a white rot fungus-Phanerochaete chrysosporium was added into the pyrene degradation experiments. Through optimizing culture conditions such ascomponent of nutrition, pH, temperature and DO, P. Chrysosporium has successfully cultivated cooperated with above two Bacillus sp.. The individual growth of bacteria and white rot fungus in the consortium was also investigated to find outthe coordinated conditions of them. The consortium of them greatly increased pyrene degradation rate (PDR). The overall PDR by the consortium was up to 99.5%, indicating much greater than the separate microorganism. Except for the adsorption to the cell wall, pyrene assimilation rate (PAR) was also up to 90%. Furthermore, the consortium reduced the threshold of pyrene from 12%to 0.5%in the extreme. Consequently, ecological risk of pyrene to environment was reduced to a minimum level. Intermediate metabolite compounds such as 1-hydroxy-2-naphthoic acid (1H2N) were isolated and identified in the degradation experiment.The accumulation and utilization of 1H2N and its equivalents were measured. Thehigh level accumulation of 1H2N and its equivalents were found in degradation experiments and up to 5.16 mg·L-1, equivalent to 110.9%of its theoretical yield, which further proved that polyphenolic substances are firstly generated in pyrene degradation pathway.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2005年第2期318-321,共4页
Journal of Agro-Environment Science
基金
国家自然科学基金资助(402173036)
南开大学学生创新基金
关键词
白腐真菌
芽孢杆菌
生物降解
芘
white rot fungi
Bacillus sp.
biodegradation
pyrene
