Diez M Cristina, Llafquen Cesar, Fincheira Paola, Lamilla Claudio, Briceño Gabriela, Schalchli Heidi
Chemical Engineering Department, University of La Frontera, Av. Francisco Salazar 01145, Temuco 4780000, Chile.
Biotechnological Research Center Applied to the Environment (CIBAMA-BIOREN), University of La Frontera, Av. Francisco Salazar 01145, Temuco 4780000, Chile.
Microorganisms. 2022 Sep 23;10(10):1892. doi: 10.3390/microorganisms10101892.
Biosurfactant-producing bacteria can be found in contaminated environments such as biopurification systems (BPS) for pesticide treatments. A total of 18 isolates were screened to determine their ability to produce extracellular biosurfactants, using olive oil as the main carbon source. Out of the eighteen isolates, two strains (C11 and C27) were selected for biosurfactant production. The emulsification activities of the C11 and C27 strains using sunflower oil was 58.4 and 53.7%, respectively, and 46.6 and 48.0% using olive oil. Using molecular techniques and MALDI-TOF, the strains were identified as (C11) and (C27). The submerged cultivation of the two selected strains was carried out in a 1 L stirred-tank bioreactor. The maximum biosurfactant production, indicated by the lowest surface tension measurement, was similar (46 and 45 mN/m) for both strains, independent of the fact that the biomass of the C11 strain was 50% lower than the biomass of the C27 strain. The partially purified biosurfactants produced by C11 and C27 were characterized as a lipopeptide and a glycolipid, respectively. These outcomes highlight the potential of the selected biosurfactant-producing microorganisms for improving pesticides' bioavailability and therefore the degradational efficacy of BPS.
产生物表面活性剂的细菌可在受污染的环境中找到，如用于农药处理的生物净化系统（BPS）。总共筛选了18株菌株，以确定它们利用橄榄油作为主要碳源产生细胞外生物表面活性剂的能力。在这18株菌株中，选择了两株（C11和C27）用于生物表面活性剂的生产。C11和C27菌株对向日葵油的乳化活性分别为58.4%和53.7%，对橄榄油的乳化活性分别为46.6%和48.0%。利用分子技术和基质辅助激光解吸电离飞行时间质谱（MALDI-TOF），将这些菌株鉴定为（C11）和（C27）。在1 L搅拌罐式生物反应器中对所选的两株菌株进行了深层培养。通过最低表面张力测量表明，两株菌株的最大生物表面活性剂产量相似（46和45 mN/m），尽管C11菌株的生物量比C27菌株低50%。C11和C27产生的部分纯化生物表面活性剂分别被表征为脂肽和糖脂。这些结果突出了所选产生物表面活性剂微生物在提高农药生物利用度以及因此提高BPS降解效率方面的潜力。
