Department of Chemical Engineering, Universidade Federal do Ceará, Brazil.
Department of Organic and Inorganic Chemistry, Universidade Federal do Ceará, Brazil.
Colloids Surf B Biointerfaces. 2019 Mar 1;175:256-263. doi: 10.1016/j.colsurfb.2018.11.062. Epub 2018 Nov 27.
The ability of some microorganisms to use clarified cashew apple juice as carbon and energy source for biosurfactant production was assessed under strict controlled conditions. Twelve strains of Bacillus were isolated and evaluated regarding their biosurfactant production capabilities. The biosurfactant obtained with these selected strains showed the capacity of decreasing the surface tension of water from 72.0 to 31.8 mN.m and the interfacial tension of n-hexadecane to 27.2 mN.m, with a critical micelle concentration of 12.5 mg.L. Not only did the biosurfactant present excellent stability to pH, temperature and salinity, it also showed emulsifying properties in different hydrocarbons. The behavior of the phase diagrams showed the potential of the produced biosurfactant to obtain relatively-stable emulsions for up to 96 h, which allows for its application in several areas. The semi-purified biosurfactant did not show toxicity against Lactuca sativa (lettuce) or Artemia salina (microcrustacean), presenting an LC of 612.27 μ mL. The surfactant was characterized as being a cyclic lipopeptide with molecular structure similar to that of surfactin. Furthermore, through the employment of the surfactant produced, the remediation effect in oil-contaminated soil could be significantly improved.
在严格控制的条件下，评估了一些微生物利用澄清的腰果苹果汁作为碳源和能源生产生物表面活性剂的能力。分离出 12 株芽孢杆菌，并评估了它们生产生物表面活性剂的能力。从这些选定的菌株中获得的生物表面活性剂具有将水的表面张力从 72.0 降低到 31.8 mN.m 和十六烷的界面张力降低到 27.2 mN.m 的能力，临界胶束浓度为 12.5 mg.L。生物表面活性剂不仅具有出色的 pH 值、温度和盐度稳定性，还具有在不同碳氢化合物中乳化的特性。相图的行为表明，所产生的生物表面活性剂具有获得相对稳定乳液的潜力，最长可达 96 小时，这使其能够在多个领域得到应用。半纯化的生物表面活性剂对莴苣（生菜）或卤虫（微甲壳类动物）没有显示出毒性，LC 值为 612.27 μ mL。该表面活性剂被鉴定为环状脂肽，其分子结构与表面活性剂相似。此外，通过使用所产生的表面活性剂，可以显著提高受污染土壤的修复效果。
