Integrated Bioprocess Laboratory, Department of Biotechnology, SRM Institute of Science and Technology, Kathankulathur, Tamil Nadu, India.
Laboratorio Fisiología Molecular Microorganismos Extremófilos, Centro de Investigaciones en Dinámica Celular. Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico.
J Environ Manage. 2020 Apr 15;260:110153. doi: 10.1016/j.jenvman.2020.110153. Epub 2020 Jan 27.
Bioremediation of polycyclic aromatic hydrocarbons (PAHs) in soil matrix is often arbitrated by the presence of soil organic matter (SOM). The present study focuses on determining the effect of the soil organic content on the mycoremediation of two model PAHs, phenanthrene (Phe) and benzo(a) pyrene (BaP) through microcosm studies. On comparing various microcosm strategies, a maximum degradation of Phe (99%) and BaP (48.5%) in soil bioaugmented with Pleurotus dryinus IBB 903, followed by, biostimulation with the degradation of Phe (89.9%) and BaP (24.8%) were noted. On relating the degradation pattern with lignolytic enzyme cocktail production, a laccase activity of 108 U/Kg at day 21, aryl alcohol oxidase (411 U/Kg) and manganese peroxidase (52.2 U/Kg) at day 14 along with lignin peroxidase (481 U/Kg) at day 21 were noted in fungal augmented soils, which were comparatively higher than levels observed in the bio-stimulation. Investigating the impact of different concentration of SOM (3-12%), a maximum remediation of Phe by 100% at 9% SOM in days 28 and 58.19% for BaP at 12% SOM, respectively was exhibited. Further, the biosorption effect of PAHs in abiotic condition showed a positive correlation with the increase in SOM, with a maximum adsorption of 3.78% Phe, and 6.93% BaP. The results support that the nominal adsorption ability of SOM, and helps in enhancing the microbial growth, thereby improving their degradation potentials, when less than 6% of SOM was utilized. Overall, this work establishes the critical role of organic matter in the soil with reference by simultaneous stimulation and degradation capability in complete PAHs remediation.
土壤有机质（SOM）的存在常常影响多环芳烃（PAHs）在土壤基质中的生物修复。本研究通过微宇宙研究，重点确定土壤有机含量对两种模式 PAHs（菲（Phe）和苯并（a）芘（BaP））的真菌修复的影响。在比较各种微宇宙策略时，发现被干蘑菇（Pleurotus dryinus）IBB 903 生物增强的土壤中 Phe（99%）和 BaP（48.5%）的最大降解，其次是生物刺激，Phe（89.9%）和 BaP（24.8%）的降解。在将降解模式与木质素酶鸡尾酒的产生相关联时，在真菌增强的土壤中，第 21 天观察到漆酶活性为 108 U/Kg，第 14 天芳基醇氧化酶（411 U/Kg）和锰过氧化物酶（52.2 U/Kg）以及第 21 天木质素过氧化物酶（481 U/Kg），这比生物刺激中观察到的水平要高。研究不同 SOM 浓度（3-12%）的影响时，在第 28 天和第 58 天，SOM 为 9%时 Phe 的最大修复率为 100%，SOM 为 12%时 BaP 的最大修复率为 58.19%。此外，在非生物条件下 PAHs 的生物吸附作用与 SOM 的增加呈正相关，最大吸附量为 3.78%的 Phe 和 6.93%的 BaP。结果表明，当 SOM 小于 6%时，SOM 的名义吸附能力有助于增强微生物的生长，从而提高其降解潜力。总的来说，这项工作确定了有机质在土壤中的关键作用，并参考了同时刺激和降解能力在完全 PAHs 修复中的作用。
