The increasing resistance of pathogenic microorganisms to antimicrobials has driven the search for safe and sustainable alternatives. In this context, microbial biosurfactants have gained prominence due to their antimicrobial activity, low toxicity, and high stability under extreme conditions. This study presents the production and characterization of a biosurfactant with antimicrobial potential, obtained from Bacillus subtilis isolated from soil, for application in the control of resistant strains. Bacterial identification was performed using mass spectrometry (MALDI-TOF), confirming it as Bacillus subtilis. The strain B. subtilis UCP 1533 was cultivated using different carbon sources (glucose, soybean oil, residual frying oil, and molasses) and nitrogen sources (ammonium chloride, sodium nitrate, urea, and peptone), with evaluations at 72, 96, and 120 h. The best condition involved a mineral medium supplemented with 2% soybean oil and 0.12% corn steep liquor, resulting in the production of 16 g·L⁻¹ of biosurfactant, with a critical micelle concentration (CMC) of 0.3 g·L⁻¹ and a reduction in water surface tension to 25 mN·m⁻¹. The biosurfactant showed an emulsification index of 100% for used motor oil and ranged from 50% to 100% for different vegetable oils, maintaining stability across a wide range of pH, salinity, and temperature. FT-IR and NMR analyses confirmed its lipopeptide nature and anionic charge. Toxicity tests with Tenebrio molitor larvae showed 100% survival at all the tested concentrations. In phytotoxicity assays, seed germination rates above 90% were recorded for Solanum lycopersicum and Lactuca sativa. Antimicrobial tests revealed inhibitory activity against resistant strains of Escherichia coli and Pseudomonas aeruginosa, as well as against species of the genus Candida (C. glabrata, C. lipolytica, C. bombicola, and C. guilliermondii), highlighting the biosurfactant as a promising alternative in combating antimicrobial resistance (AMR). These results indicate the potential application of this biosurfactant in the development of antimicrobial agents for pharmaceutical formulations and sustainable strategies for phytopathogen control in agriculture.

Microbial biosurfactants have emerged as natural and sustainable alternatives to synthetic surfactants used in the food industry, due to the growing demand for biodegradable and safe ingredients. Produced by bacteria, fungi, and yeasts, these compounds exhibit important physicochemical properties, such as emulsifying capacity, surface tension reduction, foam stabilization, and favorable interaction with different food matrices. In addition to their technological function, they exhibit relevant biological activities, including antioxidant and antimicrobial action, which contribute to the control of lipid oxidation and microbiological deterioration. These characteristics make biosurfactants attractive for applications in emulsions, fermented beverages, aerated products, probiotic systems, and bioactive packaging. The objective of this work is to provide a narrative literature review that integrates recent advances in the production, functionality, safety, sustainability, and application perspectives of biosurfactants in the food sector. In the field of production, biotechnological advances have made it possible to overcome historical limitations such as high cost and low yield. Strategies such as the use of agro-industrial waste, metabolic engineering, microbial co-cultures, continuous fermentations, and in situ removal techniques have increased efficiency and reduced environmental impacts. Despite the advances, significant challenges remain. Future prospects and advances tend to facilitate industrial adoption and consolidate biosurfactants as strategic ingredients for the development of more sustainable, functional, and technologically advanced foods.

Biosurfactants are a group of environmentally friendly amphiphilic molecules that are applicable in numerous industries as essential biotechnology products, such as food production, cleaning products, pharmacology, cosmetics, pesticides, textiles and oil and gas fields. In this sense, and knowing the potential of these biomolecules, the aim of this work was to produce a biosurfactant, characterize it regarding its chemical and surfactant properties and investigate its potential in the removal of contaminants and in the cleaning of cotton fabrics. The biosurfactant was initially obtained from the cultivation of the microorganism Candida glabrata UCP 1002 in medium containing distilled water with 2.5% residual frying oil, 2.5% molasses and 2.5% corn steep liquor agitated at 200 rpm for 144 h. The biosurfactant reduced the surface tension of water from 72 to 29 mN/m. The toxicity potential of the biosurfactant was evaluated using Tenebrio molitor larvae and demonstrated non-toxicity. The biosurfactant was applied as a degreaser of engine oil on cotton fabric, and showed 83% (2× CMC), 74% (1× CMC) and 78% (1/2× CMC) oil removal. Therefore, the biosurfactant produced in this work has promising surfactant and emulsifying properties with potential for application in various industrial segments.