Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
J Environ Sci (China). 2012;24(5):926-33. doi: 10.1016/s1001-0742(11)60865-6.
The contamination of soils by polycyclic aromatic hydrocarbons (PAHs) is a widespread environmental problem and the remediation of PAHs from these areas has been a major concern. The effectiveness of many in situ bioremediation systems may be constrained by low contaminant bioavailability due to limited aqueous solubility or a large magnitude of sorption. The objective of this research was to evaluate the effect of methyl-beta-cyclodextrin (MCD) on bioaugmentation by Paracoccus sp. strain HPD-2 of an aged PAH-contaminated soil. When 10% (W/W) MCD amendment was combined with bioaugmentation by the PAH-degrading bacterium Paracoccus sp. strain HPD-2, the percentage degradation of total PAHs was significantly enhanced up to 34.8%. Higher counts of culturable PAH-degrading bacteria and higher soil dehydrogenase and soil polyphenol oxidase activities were observed in 10% (W/W) MCD-assisted bioaugmentation soil. This MCD-assisted bioaugmentation strategy showed significant increases (p < 0.05) in the average well color development (AWCD) obtained by the BIOLOG Eco plate assay, Shannon-Weaver index (H) and Simpson index (lambda) compared with the controls, implying that this strategy at least partially restored the microbiological functioning of the PAH-contaminated soil. The results suggest that MCD-aided bioaugmentation by Paracoccus sp. strain HPD-2 may be a promising practical bioremediation strategy for aged PAH-contaminated soils.
土壤中多环芳烃（PAHs）的污染是一个广泛存在的环境问题，这些地区的 PAHs 修复一直是人们关注的主要问题。由于有限的水溶解度或较大的吸附量，许多原位生物修复系统的有效性可能受到污染物生物可利用性低的限制。本研究的目的是评估甲基-β-环糊精（MCD）对老化 PAH 污染土壤中 Paracoccus sp. 菌株 HPD-2 生物强化的影响。当 10%（W/W）MCD 添加剂与 PAH 降解菌 Paracoccus sp. 菌株 HPD-2 的生物强化相结合时，总 PAHs 的降解率显著提高了 34.8%。在 10%（W/W）MCD 辅助生物强化土壤中，可培养的 PAH 降解菌数量更高，土壤脱氢酶和土壤多酚氧化酶活性更高。与对照相比，MCD 辅助生物强化策略使 BIOLOG Eco 板测定法获得的平均好氧颜色发展（AWCD）、香农-威弗指数（H）和辛普森指数（lambda）显著增加（p<0.05），这表明该策略至少部分恢复了 PAH 污染土壤的微生物功能。结果表明，MCD 辅助 Paracoccus sp. 菌株 HPD-2 的生物强化可能是一种很有前途的老化 PAH 污染土壤的实用生物修复策略。
