可异养微藻对海洋溢油的降解机理及其动力学特性研究

Marine oil spill has long-term damage on the marine ecological environment and resources. Therefore, marine oil spill pollution has become a major environmental problem that people face to solve. Bioremediation can deal with residual oil that physical method and chemical method cannot sweep off. It is the best way to restore the ecological environment, which has got the attention of the researchers. Microalgae, as the primary producer of marine environment, get enormous quantity, which plays a very important role in the ecological restoration after the oil spill occurred. The existing literature has reported that microalgae can use petroleum hydrocarbon degradation, but limited to the study on the degradation of petroleum hydrocarbons under autotrophic condition. The marine microalgae that can biodegrade petroleum hydrocarbons under heterotrophic condition have not reported. This study intends to study on a microalga belonging to chlorella sp., which can heterotrophically degrade petroleum hydrocarbons. The main works will be done as follows. To investigation the adsorption of microalgae on petroleum hydrocarbon removal, to evaluate the degradation efficiency of petroleum hydrocarbons in the heterotrophic and mixotrophic cultivation conditions, to optimize the growth conditions in different nutritional conditions and to explore its physico-chemical process and mechanism, especially characteristics of petroleum hydrocarbons utilization dynamics and degradation mechanism under the heterotrophic and mixotrophic conditions, and to uncover remediation effect of oil spill and suitability of the microalgae under heterotrophic - mixotrophic alternate conditions. This can provide theoretical basis and technical support on microalgae getting good performance on the ecological restoration after the oil spill occurrs.

溢油对海洋生态环境和海洋资源都有长期的危害，海洋溢油污染已经成为人们必须面对的重大环境问题。微生物修复技术可以处理物理方法和化学方法无法清除的残余溢油是恢复生态环境的最佳途径，得到研究者的重视。微藻作为海洋环境中主要的初级生产者，数量巨大，对溢油发生后生态修复发挥了十分重要的作用。虽然已有文献报道微藻可降解利用石油烃，但均局限于自养降解石油烃的研究，对具有异养能力的海洋微藻降解石油烃的研究未见报道。本研究拟选择一株可异养海水小球藻作为研究对象，考察微藻吸附作用对石油烃去除的贡献，评价其在异养、混养条件下对石油烃的降解性能，优化其在不同营养条件下的生长条件，研究其生物物理化学过程与机理，尤其是异养和混养条件下小球藻对石油烃利用的动力学特性与石油烃的降解机理；探索混养/异养交替条件下，小球藻对海洋溢油修复的修复效果和适宜性，为海洋溢油发生后微藻发挥其生态修复功能提供理论基础与技术支撑。

溢油对海洋生态环境和海洋资源都有长期的危害，溢油污染已经成为人们必须面对的重大环境问题。微生物修复技术可以处理物理方法和化学方法无法清除的残余溢油是恢复生态环境的最佳途径，得到研究者的重视。微藻作为海洋环境中主要的初级生产者，数量巨大，对溢油发生后的生态修复发挥了十分重要的作用。虽然已有文献报道微藻可降解利用石油烃，但局限于自养降解石油烃的研究，对具有异养能力的海洋微藻降解石油烃的研究未见报道。本研究拟选择一株可异养海水小球藻作为研究对象，考察了微藻吸附作用对石油烃去除的贡献，评价了其在异养、混养条件下对石油烃的降解性能，优化了其在不同营养条件下的生长条件，研究了其生物物理化学过程与机理，尤其是异养和混养条件下小球藻对石油烃的利用的动力学特性与石油烃的降解机理；探索了混养/异养交替条件下，小球藻对海洋溢油修复的修复效果和适宜性。首次明确了海水小球藻对石油烃异养、混养降解的行为及其机制。建立了其吸附降解动力学方程。在异养条件下与混养条件下，温度15-35℃、pH7-8.5、盐度20-35‰时，小球藻对原油均有较强的降解作用，去除效率均可在40%以上，15 d小球藻对原油异养降解效率可达60.6%，混养降解效率可达72.7%。功能酶在小球藻降解石油烃过程起到关键作用，基于转录组和小球藻降解特性分析建立了小球藻异养和混养代谢石油烃的机制模型。进行了异养-混养交替模拟实验，在模拟实验条件下微藻对原油也具有较高的降解效率，15d对0.5 g/L原油降解效率可达52.3%。初步构建了海洋环境中小球藻去除溢油的机制及动力学理论体系。为海洋溢油发生后微藻快速发挥其生态修复功能提供理论基础与技术支撑。