Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, San Luis Potosí, SLP, Mexico. ; Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados del IPN, Col. San Pedro Zacatenco, Mexico, D.F., Mexico.
Braz J Microbiol. 2013 Oct 30;44(2):595-605. doi: 10.1590/S1517-83822013000200040. eCollection 2013.
In situ biosurfactant (rhamnolipid) production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus), P. putida addition, and addition of both (P. putida and nutrients). The results were compared against a control treatment that consisted of adding only sterilized water to the soils. In treatment with native microorganisms (non-irradiated soils) supplemented with P. putida, the removal of total petroleum hydrocarbons (TPH) was 40.6%, the rhamnolipid production was 1.54 mg/kg, and a surface tension of 64 mN/m was observed as well as a negative correlation (R = -0.54; p < 0.019) between TPH concentration (mg/kg) and surface tension (mN/m), When both bacteria and nutrients were involved, TPH levels were lowered to 33.7%, and biosurfactant production and surface tension were 2.03 mg/kg and 67.3 mN/m, respectively. In irradiated soil treated with P. putida, TPH removal was 24.5% with rhamnolipid generation of 1.79 mg/kg and 65.6 mN/m of surface tension, and a correlation between bacterial growth and biosurfactant production (R = -0.64; p < 0.009) was observed. When the nutrients and P. putida were added, TPH removal was 61.1%, 1.85 mg/kg of biosurfactants were produced, and the surface tension was 55.6 mN/m. In summary, in irradiated and non-irradiated soils, in situ rhamnolipid production by P. putida enhanced TPH decontamination of the soil.
在对来自油井钻探作业的老化受污染土壤进行生物强化和生物刺激处理以去除烃类时，实现了恶臭假单胞菌 CB-100 的原位生物表面活性剂（鼠李糖脂）生产。对几种辐照和未辐照土壤的处理进行了鼠李糖脂生产和污染物去除的测定：添加营养物（氮和磷）、添加恶臭假单胞菌和同时添加（恶臭假单胞菌和营养物）。将结果与仅向土壤中添加灭菌水的对照处理进行了比较。在添加土著微生物（未辐照土壤）并补充恶臭假单胞菌的处理中，总石油烃（TPH）的去除率为 40.6%，鼠李糖脂的产量为 1.54mg/kg，表面张力为 64mN/m，并且TPH 浓度（mg/kg）与表面张力（mN/m）之间存在负相关（R=-0.54；p<0.019）。当同时存在细菌和营养物时，TPH 水平降低到 33.7%，生物表面活性剂的产量和表面张力分别为 2.03mg/kg 和 67.3mN/m。在经辐照的土壤中添加恶臭假单胞菌，TPH 去除率为 24.5%，鼠李糖脂生成量为 1.79mg/kg，表面张力为 65.6mN/m，观察到细菌生长与生物表面活性剂生成之间的相关性（R=-0.64；p<0.009）。当添加营养物和恶臭假单胞菌时，TPH 去除率为 61.1%，产生了 1.85mg/kg 的生物表面活性剂，表面张力为 55.6mN/m。总之，在辐照和未辐照的土壤中，恶臭假单胞菌的原位鼠李糖脂生产增强了土壤中 TPH 的脱污染。
