一株异养氨氧化青霉（Penicillium sp.）特性研究

[目的]对分离自鸡粪好氧堆肥的一株氨氧化青霉(Penicillium sp.)M25-22进行异养氨氧化特性的研究,为该菌在鸡粪等固体废弃物好氧堆肥过程中的应用提供依据.[方法]在以铵盐为唯一氮源的培养基中,研究该菌生成亚硝酸盐氮与硝酸盐氮的能力;调整培养基的碳源种类、氮源种类、蔗糖浓度、铵态氮浓度、pH和培养温度等,研究环境条件对该菌氨氧化能力的影响.[结果]该菌在以铵盐为唯一氮源的培养基中,菌体生长量及铵态氮利用率在1-5 d迅速增加;硝酸盐氮浓度3-5 d上升迅速,以后维持在1.1-1.2 μg·mL~(-1);同时有少量亚硝酸盐氮生成.该菌在以葡萄糖、蔗糖、淀粉或纤维素为唯一碳源的培养基中均进行异养氨氧化,能氧化硫酸铵、蛋白胨、乙酰胺、尿素或L-天冬氨酸中的负三价氮,其中可溶性淀粉、纤维素、蛋白胨等缓效碳、氮源更有利.该菌在以蔗糖为唯一碳源、铵盐为唯一氮源的培养基中,异养氨氧化的最适条件为,蔗糖浓度12 g·L~(-1)、铵态氮浓度2.438 mg·mL~(-1)、pH 7.5和培养温度30℃.[结论]M25-22存在细菌的无机氮氧化途径,且能将生成的亚硝酸盐氮迅速氧化为硝酸盐氮,其氨氧化作用属于次级代谢.该菌能以多种有机物为碳源进行异养氨氧化,能氧化多种氮源中的负三价氮素,且在高有机物,高铵态氮浓度下表现出较强的异养氨氧化能力,因而在鸡粪等固体废弃物的好氧堆肥实践中具有应用价值.

Study on the Characteristics of a Strain of Penicillium sp.With the Capacity of Heterotrophic Ammonium Oxidation

Objective The objective of this study was to reveal the characteristics of a strain (M25-22) of Penicillium sp.with the capacity of heterotrophic ammonium oxidation isolated from chicken feces compost,and to provide scientific references for its application in aerobic composting.Method Media with ammonium salt as the sole nitrogen source was used to determine the heterotrophic ammonium oxidation activity of the strain.Some environmental factors,such as compositions of carbon and nitrogen sources,concentrati...