Instituto Politécnico Nacional, Centro de Investigación en Biotecnología Aplicada, Carretera Estatal San Inés Tecuexcomac-Tepetitla Km 1.5, C.P. 90700, Tepetitla de Lardizabal, Tlaxcala, Mexico.
Universidad Politécnica de Pachuca, Laboratorio de Microbiología Molecular, Carretera Pachuca-Cd, Sahagún, Km 20, Ex-Hacienda de Santa Bárbara, Zempoala, Hidalgo, Mexico.
Chemosphere. 2017 Apr;172:120-126. doi: 10.1016/j.chemosphere.2016.12.038. Epub 2016 Dec 21.
Bioremediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soils through the biostimulation and bioaugmentation processes can be a strategy for the clean-up of oil spills and environmental accidents. In this work, an induced microbial selection method using PAH-polluted soils was successfully used to construct two microbial consortia exhibiting high degradation levels of low and high molecular weight PAHs. Six fungal and seven bacterial native strains were used to construct mixed consortia with the ability to tolerate high amounts of phenanthrene (Phe), pyrene (Pyr) and benzo(a)pyrene (BaP) and utilize these compounds as a sole carbon source. In addition, we used two engineered PAH-degrading fungal strains producing heterologous ligninolytic enzymes. After a previous selection using microbial antagonism tests, the selection was performed in microcosm systems and monitored using PCR-DGGE, CO evolution and PAH quantitation. The resulting consortia (i.e., C1 and C2) were able to degrade up to 92% of Phe, 64% of Pyr and 65% of BaP out of 1000 mg kg of a mixture of Phe, Pyr and BaP (1:1:1) after a two-week incubation. The results indicate that constructed microbial consortia have high potential for soil bioremediation by bioaugmentation and biostimulation and may be effective for the treatment of sites polluted with PAHs due to their elevated tolerance to aromatic compounds, their capacity to utilize them as energy source.
通过生物刺激和生物增强过程对多环芳烃（PAHs）污染土壤进行生物修复，可以作为清理溢油和环境事故的一种策略。在这项工作中，成功地使用 PAH 污染土壤的诱导微生物选择方法构建了两个具有高分子量和低分子量 PAHs 高降解水平的微生物群落。使用六种真菌和七种细菌原生菌株构建了混合群落，具有耐受大量菲（Phe）、芘（Pyr）和苯并[a]芘（BaP）的能力，并将这些化合物用作唯一碳源。此外，我们使用了两种产生异源木质素降解酶的工程化 PAH 降解真菌菌株。在使用微生物拮抗试验进行了初步选择之后，在微宇宙系统中进行了选择，并使用 PCR-DGGE、CO 释放和 PAH 定量监测。在两周的孵育后，所得的两个混合群落（即 C1 和 C2）能够降解混合物中高达 92%的 Phe、64%的 Pyr 和 65%的 BaP，混合物中 Phe、Pyr 和 BaP 的浓度为 1000 mg kg-1（1:1:1）。结果表明，构建的微生物群落通过生物增强和生物刺激具有很高的土壤生物修复潜力，并且由于其对芳香族化合物的高耐受性、将其用作能源的能力，可能对 PAHs 污染的场地处理有效。
