Comparative analysis of the antibacterial activity of oils from ungurahui fruit, kukui nut, and black cumin seeds

The research was carried out to analyze the antimicrobial activity of oils from ungurahui fruit, kukui nut, and black cumin seeds. The antimicrobial activity of the oils was evaluated using standard laboratory test strains of Pseudomonas aeruginosa, Bacillus cereus, Escherichia coli, Staphylococcus aureus. The experimental method was based on a standard seeding algorithm in accordance with a modification involving the replacement of discs with hollow cylinders with a volume of 0.2 ml and an inner diameter of 5 mm when testing liquid antimicrobials (OFS.1.2.4.0010.18 "Determination of antimicrobial activity of antibiotics by diffusion into agar"). It has been established that oils from ungurahui fruit, black cumin seeds and kukui nut have an antibacterial effect on Pseudomonas aeruginosa, the diameters of the growth suppression zones of microorganisms are 11.4±0.14; 14.1±0.11 and 13.2±0.07 mm, respectively. For the remaining test strains, ungurahui and kukui nut oils had a bactericidal effect, suppressing the growth of Bacillus cereus and Escherichia coli locally only under the cylinder. The growth of Staphylococcus aureus was slightly suppressed by kukui nut oil (under the cylinder). Thus, kukui nut oil exhibits varying degrees of pronounced antimicrobial activity against all four test strains. At the same time, the inhibition of the reproduction of Pseudomonas aeruginosa is provided to the greatest extent by black cumin seed oil. The bactericidal properties of black cumin oil are due to the high concentration of biologically active substances (thymol, carvacrol, p-cymene, α-thuyene, α-pinene, β-pinene, t-anethole and other aromatic hydrocarbons). In general, the studied oils can be used as natural biologically active additives in medicine, veterinary, and forage production.