Villaverde Jaime, Láiz Leonila, Lara-Moreno Alba, González-Pimentel J L, Morillo Esmeralda
Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS-CSIC), Seville, Spain.
Front Microbiol. 2019 Nov 14;10:2588. doi: 10.3389/fmicb.2019.02588. eCollection 2019.
A PAHs-contaminated industrial soil was analyzed using PCR amplification of the gene 16S ribosomal RNA for the detection and identification of different isolated bacterial strains potentially capable of degrading PAHs. Novel degrader strains were isolated and identified as 2BC8 and JR62, which were able to degrade PYR in solution, achieving a mineralization rate of about 1% day. was also able to mineralize PYR in slurry systems using three selected soils, and the total extent of mineralization (once a plateau was reached) increased 4.5, 21, and 57.5% for soils LT, TM and CR, respectively, regarding the mineralization observed in the absence of the bacterial degrader. Soil TM contaminated with PYR was aged for 80 days and total extent of mineralization was reduced (from 46 to 35% after 180 days), and the acclimation period increased (from 49 to 79 days). Hydroxypropyl-ß-cyclodextrin (HPBCD) was used as a bioavailability enhancer of PYR in this aged soil, provoking a significant decrease in the acclimation period (from 79 to 54 days) due to an increase in PYR bioavailable fraction just from the beginning of the assay. However, a similar global extension of mineralization was obtained. was then added together with HPBCD to this aged TM soil contaminated with PYR, and the total extent of mineralization decreased to 25% after 180 days, possibly due to the competitive effect of endogenous microbiota and the higher concentration of PYR in the soil solution provoked by the addition of HPBCD, which could have a toxic effect on the strain.
对受多环芳烃污染的工业土壤进行分析，采用16S核糖体RNA基因的聚合酶链反应扩增，以检测和鉴定可能能够降解多环芳烃的不同分离细菌菌株。分离出新型降解菌株并鉴定为2BC8和JR62，它们能够在溶液中降解芘，矿化率约为每天1%。在使用三种选定土壤的泥浆系统中也能够使芘矿化，与在没有细菌降解剂的情况下观察到的矿化相比，对于LT、TM和CR土壤，矿化的总程度（一旦达到平稳期）分别增加了4.5%、21%和57.5%。受芘污染的TM土壤老化80天，矿化总程度降低（180天后从46%降至35%），驯化期延长（从49天增至79天）。羟丙基-β-环糊精（HPBCD）用作该老化土壤中芘的生物利用度增强剂，由于从试验开始芘的生物可利用部分增加，导致驯化期显著缩短（从79天降至54天）。然而，获得了相似的矿化总体程度。然后将JR62与HPBCD一起添加到受芘污染的该老化TM土壤中，180天后矿化总程度降至25%，这可能是由于内源性微生物群的竞争作用以及添加HPBCD引起的土壤溶液中芘浓度升高，这可能对JR62菌株产生毒性作用。
