Despite their potential, the performance of biosurfactants in soil systems is often limited by adsorption to clay minerals, silt particles, and organic matter, influenced by ion exchange and alterations in solubility equilibria. Surfactin’s effectiveness was evaluated across engineered soil textures by formulating standardized mixtures by diluting silty clay loam with artificial sand to address these limitations. The approach enabled the isolation of texture effects while maintaining consistent quality of physicochemical properties.
The results revealed that soils approximating sandy loam textures responded most favorably, with a 25% reduction in water-surface contact angle and a twofold increase in water retention. These findings highlight the critical role of soil texture in mediating biosurfactant efficacy and support the development of site-specific application strategies. This work advances our understanding of surfactant–soil interactions and underscores the potential for scalable, bio-based soil amendments in sustainable agriculture.