Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
Chemosphere. 2017 Sep;182:316-324. doi: 10.1016/j.chemosphere.2017.05.020. Epub 2017 May 5.
The inoculation of rice straw biochar with PAH-degrading Mycobacterium gilvum (1.27 × 10 ± 1.24 × 10 cell g), and the subsequent amendment of this composite material to PAHs contaminated (677 mg kg) coke plant soil, was conducted in order to investigate if would enhance PAHs biodegradation in soils. The microbe-biochar composite showed superior degradation capacity for phenanthrene, fluoranthene and pyrene. Phenanthrene loss in the microbe-biochar composite, free cell alone and biochar alone treatments was, respectively, 62.6 ± 3.2%, 47.3 ± 4.1% and non-significant (P > 0.05); whereas for fluoranthene loss it was 52.1 ± 2.3%; non-significant (P > 0.05) and non-significant (P > 0.05); and for pyrene loss it was 62.1 ± 0.9%; 19.7 ± 6.5% and 13.5 ± 2.8%. It was hypothesized that the improved remediation was underpinned by i) biochar enhanced mass transfer of PAHs from the soil to the carbonaceous biochar "sink", and ii) the subsequent degradation of the PAHs by the immobilized M. gilvum. To test this mechanism, a surfactant (Brij 30; 20 mg g soil), was added to impede PAHs mass transfer to biochar and sorption. The surfactant increased solution phase PAH concentrations and significantly (P < 0.05) reduced PAH degradation in the biochar immobilized M. gilvum treatments; indicating the enhanced degradation occurred between the immobilized M. gilvum and biochar sorbed PAHs.
将具有多环芳烃降解能力的分枝杆菌（1.27×10±1.24×10细胞g）接种到水稻秸秆生物炭中，然后将该复合材料添加到多环芳烃污染（677 mg kg）的炼焦厂土壤中，以研究其是否能增强土壤中多环芳烃的生物降解能力。该微生物-生物炭复合材料对菲、荧蒽和芘表现出较高的降解能力。在微生物-生物炭复合材料、游离细胞和生物炭单独处理中，菲的损失分别为 62.6±3.2%、47.3±4.1%和无显著差异（P>0.05）；而荧蒽的损失分别为 52.1±2.3%、无显著差异（P>0.05）和无显著差异（P>0.05）；芘的损失分别为 62.1±0.9%、19.7±6.5%和 13.5±2.8%。据推测，这种改良修复的原因是：i）生物炭增强了多环芳烃从土壤向碳素生物炭“汇”的传质；ii）随后被固定的分枝杆菌对多环芳烃的降解。为了验证这一机制，向土壤中添加了一种表面活性剂（Brij 30；20 mg g土壤），以阻碍多环芳烃向生物炭的传质和吸附。表面活性剂增加了溶液相中多环芳烃的浓度，并显著（P<0.05）降低了生物炭固定化分枝杆菌处理中的多环芳烃降解，表明增强的降解发生在固定化分枝杆菌和生物炭吸附的多环芳烃之间。
