Rhamnolipids (RMLs) have more effectiveness for specific uses according to their homologue proportions. Thus, the novelty of this work was to compare mono‐RMLs and di‐RMLs physicochemical properties on microbial enhanced oil recovery (MEOR) applications. For this, RML produced by three strains of Pseudomonas aeruginosa containing different homologues proportion were used: a mainly mono‐RMLs producer (mono‐RMLs); a mainly di‐RMLs producer (di‐RMLs), and the other one that produces relatively balanced amounts of mono‐RML and di‐RML homologues (mono/di‐RML). For mono‐RML, the most abundant molecules were Rha‐C₁₀C₁₀ (m/z 503.3), for di‐RML were RhaRha‐C₁₀C₁₀ (m/z 649.4) and for Mono/di‐RML were Rha‐C₁₀C₁₀ (m/z 503.3) and RhaRha‐C₁₀C₁₀ (m/z 649.4). All RMLs types presented robustness under high temperature and variation of salinity and pH, and high ability for oil displacement, foam stability, wettability reversal and were classified as safe for environment according to the European Union Directive No. 67/548/EEC. For all these properties, it was observed a highlight for mono‐RML. Mono‐RML presented the lowest surface tension (26.40 mN/m), interfacial tension (1.14 mN/m), and critical micellar concentration (CMC 27.04 mg/L), the highest emulsification index (EI₂₄ 100%) and the best wettability reversal (100% with 25 ppm). In addition, mono‐RML showed the best acute toxicity value (454 mg/L), making its application potential even more attractive. Based on the results, it was concluded that all RMLs homologues studied have potential for MEOR applications. However, results showed that mono‐RML stood out and have the best mechanism of oil incorporation in micelles due their most effective surface‐active physicochemical features.

中文翻译：

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单鼠李糖脂和双鼠李糖脂在微生物提高采收率 (MEOR) 应用中的比较。

鼠李糖脂 (RML) 根据其同源比例对特定用途具有更高的有效性。因此，这项工作的新颖之处在于比较了单 RML 和双 RML 在微生物提高采收率 (MEOR) 应用中的理化性质。为此，使用了含有不同同源物比例的三株铜绿假单胞菌产生的 RML ：主要是单 RMLs 生产者（mono-RMLs）；一个主要是 di-RMLs 生产者 (di-RMLs)，另一个产生相对平衡的单 RML 和 di-RML 同系物 (mono/di-RML)。对于mono-RML，最丰富的分子是Rha-C ₁₀ C ₁₀ (m/z 503.3)，对于di -RML，最丰富的分子是RhaRha-C ₁₀ C ₁₀ (m/z 649.4)，对于Mono/di-RML ，最丰富的分子是Rha- C₁₀ C ₁₀ (m/z 503.3) 和 RhaRha-C ₁₀ C ₁₀ (m/z 649.4)。所有 RML 类型在高温和盐度和 pH 值变化下都表现出稳健性，以及高驱油能力、泡沫稳定性、润湿性逆转，并根据欧盟指令 No. 67/548/EEC 被归类为对环境安全。对于所有这些特性，观察到单 RML 的一个亮点。Mono-RML 具有最低的表面张力 (26.40 mN/m)、界面张力 (1.14 mN/m) 和临界胶束浓度 (CMC 27.04 mg/L)，最高的乳化指数 (EI ₂₄100%) 和最佳润湿性逆转（100% 与 25 ppm）。此外，mono-RML 显示出最佳的急性毒性值（454 mg/L），使其应用​​潜力更具吸引力。基于结果，得出的结论是所有研究的 RML 同系物都具有 MEOR 应用的潜力。然而，结果表明，mono-RML 因其最有效的表面活性物理化学特征而脱颖而出，并具有将油掺入胶束的最佳机制。