Assessment of the physicochemical quality indicators and microbiological effects of Brazilian ozonized vegetable oils

The study of quality indicators in the process of obtaining ozonized vegetable oils is useful for monitoring the ozonation reaction. The Brazilian oils "dendê", soy, corn, rice and sunflower were studied, all of them were ozonated applying different doses of ozone. Ozonized oils were evaluated by determining the physicochemical indexes of peroxide, acidity, iodine and density in addition viscosity, fatty acid composition and microbiological activity were determined. The results showed that of the five ozonized oils evaluated, "dendê" oil exhibited a higher peroxide index, approximately 1746 mmol-equiv kg-1, using an applied ozone dose of 97 mg g^-1, during an hour and a half of the ozonation reaction. This result could be explained by its chemical composition, rich in oleic acid that facilitates the reaction with ozone due to its spatial conformation. It was also demonstrated that "dendê" oil exhibits a greater antibacterial activity with minimum inhibitory concentration (MIC) values ranging from 1.9 to 4.75 mg mL^-1against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. It is suggested that the ozonated "dendê" oil presents greater possibilities to be used in the preparation of pharmaceutical or cosmetic formulations.