Biotransformed babassu oil: volatile profile and antimicrobial action against foodborne pathogens

The development of multifunctional, natural bioingredients constitutes a promising approach for formulating food-grade alternatives to synthetic additives. In this investigation, babassu oil was subjected to enzymatic biotransformation utilizing Lipozyme^® 435 (7.0% w/v) within a solvent-free biocatalytic system comprising a 51:49 (v/v) mixture of ethanol and babassu oil. The biotransformation reactions were conducted under mild operational conditions (58 °C, 70 rpm, 6 hours), resulting in a complex mixture primarily composed of ethyl ester derivatives. Gas chromatography–mass spectrometry analysis revealed the formation of key ester compounds, including ethyl butanoate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate, which are associated with fruity, creamy, and tropical scent profiles. Sensory assessments corroborated that the biotransformed oil exhibited aroma attributes characteristic of pineapple, coconut, pear, and apple. In addition to its aromatic potential, the biotransformed oil was evaluated for antimicrobial activity against foodborne pathogens, including Salmonella ATCC 13076, Staphylococcus aureus ATCC 19095, Listeria innocua ATCC 33090, Bacillus cereus NCTC 1143, and Escherichia coli ATCC 2346. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays were performed following CLSI guidelines using broth microdilution in 96-well plates. The results demonstrated that the native babassu oil showed no antimicrobial effect. In contrast, the biotransformed oil exhibited bacteriostatic activity against most tested strains, with MIC values as low as 0.39 µL/mL for Salmonella, 0.78 µL/mL for Bacillus cereus, 3.125 µL/mL for Listeria innocua, and 6.25 µL/mL for Staphylococcus aureus. However, bactericidal activity was only observed at high concentrations (5.0–10.0%), limiting its applicability in food preservation due to the strong flavor impact. Escherichia coli proved resistant, with no inhibition detected at the concentrations tested. The antimicrobial properties are attributed to the ethyl esters produced during enzymatic alcoholysis, consistent with prior studies emphasizing the significance of esterified derivatives and essential oil constituents in inhibiting microbial growth. Although the concentrations necessary for bactericidal effects are impractical for direct application in foods, the observed bacteriostatic activity underscores potential utility in specialized contexts where both aroma enhancement and microbial control are advantageous. This study demonstrates that babassu oil, a tropical oil abundant in lauric acid, can be valorized through mild enzymatic processes to produce multifunctional ingredients endowed with both sensory and antimicrobial properties. The findings endorse biocatalysis for sustainable, natural bioingredients aligned with consumer demand for plant-based, clean-label products. Future research should optimize processes and encapsulation to improve efficacy and reduce flavor impact.