In this paper, Pseudomonas aeruginosa MTCC7815, a biosurfactant producing strain was studied for its ability to utilize waste cooking oil (WCO) as a sole carbon source for the production of biosurfactant. Culture conditions were optimized based on surface tension reduction and biomass concentration. The obtained biosurfactant was characterized using ¹H NMR, FTIR, LC–MS, and MALDI-TOF techniques. The chemical properties of the produced biosurfactant were estimated by assessing the critical micelle concentration (CMC), emulsification index (E₂₄) and oil displacement test. The optimal culture conditions were found to be similar to the natural domestic sewage such as basic pH value of 10, temperature of 25 °C and a very high WCO concentration of 40 gL⁻¹ (C/N ratio of 40/1). The biosurfactant yield was found to be significant as 11 ± 0.2 gL⁻¹ upon utilizing about 90% of WCO within 5 days of incubation. The biosurfactant produced was found to be a mixture of mono- and di-rhamnolipid in nature and comprised excellent surface active properties i.e. an extremely low CMC of 8.8 ± 0.3 mgL⁻¹, E₂₄ of 62.5 ± 0.3% and surface tension reduction up to 26.2 ± 0.5 mNm⁻¹. These results suggest the suitability of Pseudomonas aeruginosa for the biosurfactant production at commercial scale along with waste remediation in an economic way.

中文翻译：

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通过使用铜绿假单胞菌MTCC7815对废食用油进行生物降解来生产新型鼠李糖脂。

在本文中，研究了铜绿假单胞菌MTCC7815（一种生物表面活性剂生产菌株）利用废食用油（WCO）作为生产生物表面活性剂的唯一碳源的能力。根据表面张力降低和生物质浓度优化培养条件。使用¹ H NMR，FTIR，LC-MS和MALDI-TOF技术对获得的生物表面活性剂进行表征。通过评估临界胶束浓度（CMC），乳化指数（E ₂₄）和驱油试验来评估生产的生物表面活性剂的化学性质。发现最佳培养条件与天然生活污水相似，例如基本pH值为10，温度为25°C和非常高的WCO浓度为40 gL^-1（C / N比为40/1）。发现在孵育的5天内利用约90％的WCO时，生物表面活性剂的产量显着为11±0.2gL ^-1。发现生产的生物表面活性剂本质上是单鼠李糖脂和二鼠李糖脂的混合物，并具有出色的表面活性，即极低的CMC为8.8±0.3 mgL ^-1，E ₂₄为62.5±0.3％，表面张力降低至26.2±0.5mNm ^-1。这些结果表明铜绿假单胞菌适用于商业规模的生物表面活性剂生产以及以经济方式进行废物修复。