Assessment of the in vitro antimicrobial activity and fatty acid composition of crocodile oil from Crocodylus siamensis.

Crocodile oil has been traditionally used for its medicinal properties, including wound healing and antimicrobial effects. However, scientific validation of its antimicrobial activity remains limited. Although its potential to induce microbial resistance and its safety profile have been proposed in previous literature, these aspects were not addressed experimentally in the current study. This study aimed solely to evaluate the in vitro antimicrobial activity of crocodile oil using dip solution and standard microbiological approaches. Standard bacterial and fungal strains, including Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans, were tested using disk diffusion and minimum inhibitory concentration (MIC) methods. Fatty acid composition was analyzed using GC-FID. The results demonstrated significant antimicrobial activity against Staphylococcus aureus ATCC 29213, Staphylococcus aureus ATCC 43300 (methicillin-resistant), Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. No inhibition was observed against Staphylococcus epidermidis ATCC 12228 and Klebsiella pneumoniae ATCC 4352, as confirmed by both disk diffusion and MIC methods. MIC values ranged from 187.5 to 500 µL/Ml. The lowest MIC was observed for Escherichia coli (187.5 µL/mL), while MICs of 375 µL/mL were recorded for Staphylococcus aureus ATCC 43300, Enterococcus faecalis, Pseudomonas aeruginosa, and Candida albicans. The highest MIC (500 µL/mL) was observed for Staphylococcus aureus ATCC 29213. While the results are promising, further studies are necessary to evaluate safety, resistance development potential, and in vivo efficacy.