Assessing the impact of biosurfactants extracted from corn steep liquor at pilot scale on water suspensibility of metallic biocides

Abstract BACKGROUND Corn steep liquor (CSL) is a rich source of bioactive compounds, particularly biosurfactants. In this work, two biosurfactant extracts were produced successfully at a pilot scale using CSL. One was more hydrophobic and was obtained through liquid–liquid extraction with ethyl acetate (BS‐ACT). The other was more hydrophilic, obtained through solid–liquid extraction with phosphate buffer saline (PBS) (BS‐PBS). RESULTS The biosurfactant extracts (BS‐ACT and BS‐PBS) were included in biocide formulations to assess their impact on enhancing the suspensibility and solubility of different metallic active substances. The BS‐PBS extract exhibited superior properties in suspending biocides in comparison with BS‐ACT, despite BS‐ACT demonstrating a higher solubility capacity. Moreover, in comparison with chemical surfactants, BS‐ACT displayed significantly greater ability to solubilize biocides in water, whereas BS‐PBS showed suspensibility results that were comparable with synthetic surfactants. CONCLUSION Biosurfactant extracts derived from CSL act as coadjutants in metallic biocide formulations, enhancing their dissolution or suspension in water and providing a sustainable alternative to chemical surfactants. © 2025 Society of Chemical Industry.