Antimicrobial Activity of Formulated Origanum and Thyme Essential Oil Nanoemulsions-A Comparative Study
Issued Date
2024-01-01
Resource Type
ISSN
15734013
eISSN
22123881
Scopus ID
2-s2.0-85190417736
Journal Title
Current Nutrition and Food Science
Volume
20
Issue
6
Start Page
757
End Page
766
Rights Holder(s)
SCOPUS
Bibliographic Citation
Current Nutrition and Food Science Vol.20 No.6 (2024) , 757-766
Suggested Citation
Al-Asmari F., Koirala P., Rathod N.B., Alnemr T.M., Asiri S.A., Babeker M.Y., Li L., Nirmal N.P. Antimicrobial Activity of Formulated Origanum and Thyme Essential Oil Nanoemulsions-A Comparative Study. Current Nutrition and Food Science Vol.20 No.6 (2024) , 757-766. 766. doi:10.2174/1573401319666230914140953 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/98079
Title
Antimicrobial Activity of Formulated Origanum and Thyme Essential Oil Nanoemulsions-A Comparative Study
Corresponding Author(s)
Other Contributor(s)
Abstract
Introduction: This study focused on the formulation processing and antimicrobial activities of Origanum and Thyme essential oils (OEO) (TEO) and their nanoemulsions (OEON) (TEON) on gram-positive and gram-negative bacteria and yeast. Optimal nanoemulsion formulation and stability were achieved through balancing between requisite hydrophilic-lipophilic balance (rHLB) and surfactant concentration (Smix) of nanoemulsions. Methods: The smallest droplet sizes of OEON: (z-185.1 nm ± 0.85) and TEON (z-130.1 nm ± 0.60), were achieved by using 10 g/100 mL of OEO and TEO with 15 g/100 mL Smix at ultrasonication for 2 min with no phase separation. The size of nanoemulsion droplet and PDI was found to be influenced by HLB value, treatment time, and Smix concentration. Antimicrobial analyses, including a zone of inhibition, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill kinetics assay, were performed against Escherichia coli, Staphylococcus aureus, and Saccharomyces cerevisiae. Results: The antimicrobial findings demonstrated that OEO exhibited higher antimicrobial activity compared to TEO (P<0.05). Meanwhile, the OEON and TEON substantially reduced the MIC and MBC values, compared to OEO and TEO against all tested microorganisms (P<0.05). Throughout the time-kill assay, E. coli was reduced by 5 log CFU/ml within 120 minutes, while S. cerevisiae and S. aureus were eradicated after 60 and 120 minutes of incubation with OEON, respectively. Conclusion: In turn, TEON reduced E. coli by 5 log CFU/ml and S. cerevisiae by 4 log CFU/ml within 120 minutes, while S. aureus was inhibited within the same time of incubation with TEON. The nanoemulsion formulations of OEO and TEO considerably enhanced the antimicrobial properties, which provides a promising alternative plant-derived antimicrobial for pharmaceuticals and food applications.