Comparative analysis of antibacterial activity of fatty acid from Vietnamese coconut oils produced by hot-extracted and cold-pressing methods

This study investigated the antibacterial activity of fatty acids (FAs) extracted from coconut oil against Staphylococcus aureus and Methicillin-resistant S. aureus (MRSA). The FAs exhibited inhibitory effects at concentrations ≥5%, producing inhibition zones of 4 mm and above. Increasing concentration did not yield a proportional enhancement, indicating a non–dose-dependent effect. MRSA displayed slightly greater susceptibility than S. aureus at equivalent concentrations. Significant differences among concentrations were confirmed (p < 0.01). Although overall activity was comparable between cold-pressed (CCO) and hot-extracted coconut oil (HCO), FAs derived from CCO showed stronger inhibition, with minimum inhibitory concentrations (MICs) of 0.39% for both strains, compared to 0.78% for HCO against S. aureus. The superior efficacy of CCO-derived FAs likely reflects better preservation of medium-chain fatty acids—particularly lauric, capric, and caprylic acids—known for antimicrobial properties. These results highlight the influence of processing methods on the antibacterial efficacy of coconut oil–derived fatty acids.