秸秆水解液对厌氧降解多环芳烃的共代谢效应

Co-Metabolic Effect of Reed Straw Acidolysis Solution on Anaerobic Degradation of PAHs

多环芳烃为有毒、致突变、致癌且难降解的有机污染物。海洋溢油频发使多环芳烃易在海洋沉积物中富集而危害海洋生态系统和人类健康,但目前尚缺乏高效快速的生物修复方法。本研究尝试利用芦苇秸秆水解液作为共代谢碳源,建立高效的多环芳烃厌氧降解系统。采用经石油驯化的海底污泥作为接种物,秸秆水解液作为共代谢碳源,对海水介质中的四种高浓度多环芳烃进行批式厌氧降解研究。本研究连续进行100 d,对苯并[a]芘、苯并[b]荧蒽、芘和菲的去除率分别达到了71.08%、86.64%、77.86%和83.11%;其去除速率分别高达1.78 mg·L^(-1)·d^(-1)、0.21 mg·L^(-1)·d^(-1)、3.88 mg·L^(-1)·d^(-1)和4.16 mg·L^(-1)·d^(-1),实现了对高浓度多环芳烃在海水介质中的高效厌氧降解。微生物群落分析显示硫酸盐还原菌菌群为多环芳烃的厌氧降解的优势菌群,表明硫酸盐在海水厌氧降解高浓度多环芳烃体系中可能起到氧化多环芳烃和作为主要电子受体的关键作用。

Polycyclic aromatic hydrocarbons(PAHs)are organic pollutants with toxic,mutagenic and carcinogenic properties.The high frequency of marine oil spills leads to the deposition of PAHs on the seabed,which considerably harms the environment and human health.However,there is still a lack of efficient and rapid bioremediation methods.Herein,we established an efficient anaerobic degradation system for high concentration PAHs by adding reed straw acidolysis solution as co-metabolic substrate.We investigated a batch anaerobic degradation system for four high-concentration PAHs in seawater condition by using petroleum-acclimated seabed sediments as an inoculum and reed straw acidolysis solution was used as co-metabolic carbon source.After 100 d of cultivation,the removal rate of Benzo[a]pyrene,Benzo[b]fluoranthene,Pyrene and Phenanthrene were 71.08%,86.64%,77.86%and 83.11%,and the degradation efficiency were 1.78 mg·L^(-1)·d^(-1),0.21 mg·L^(-1)·d^(-1),3.88 mg·L^(-1)·d^(-1)and 4.16 mg·L^(-1)·d^(-1),respectively.It achieves efficient anaerobic degradation of high-concentration PAHs in seawater medium.Microbial community analysis showed that the sulfate-reducing bacteria is the dominant flora for anaerobic degradation of PAHs,suggested sulfate may play a key role in oxidizing PAHs and acting as the main electron acceptor in the anaerobic degradation of high concentration PAHs in seawater.