Caraway Nanoemulsion Gel: A Potential Antibacterial Treatment against Escherichia coli and Staphylococcus aureus

Abstract

Novel antibiotics are needed due to the rise of antibiotic-resistant pathogens. Traditional antibiotics are ineffective due to antibiotic-resistant microorganisms, and finding alternative therapies is expensive. Hence, plant-derived caraway (Carum carvi) essential oils and antibacterial compounds have been selected as alternatives. In this, caraway essential oil as an antibacterial treatment was investigated using a nanoemulsion gel. Using the emulsification technique, a nanoemulsion gel was developed and characterized in terms of particle size, polydispersity index, pH, and viscosity. The results showed that the nanoemulsion had a mean particle size of 137 nm and an encapsulation efficiency of 92%. Afterward, the nanoemulsion gel was incorporated into the carbopol gel and was found to be transparent and uniform. The gel had in vitro cell viability and antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The gel safely delivered a transdermal drug with a cell survival rate of over 90%. With a minimal inhibitor concentration (MIC) of 0.78 mg/mL and 0.78 mg/mL, respectively, the gel demonstrated substantial inhibition for E. coli and S. aureus. Lastly, the study demonstrated that caraway essential oil nanoemulsion gels can be efficient in treating E. coli and S. aureus, laying the groundwork for the use of caraway essential oil as an alternative to synthetic antibiotics in the treatment of bacterial infections.

Keywords: Escherichia coli; Staphylococcus aureus; antibacterial; caraway essential oil; nanoemulsion gel.

Figure 1

Evaluation of caraway essential oil’s nanoemulsion (a) Particle size; (b) Zeta potential; (c) morphololy analysis of caraway nanoemulsion by TEM.

Figure 2

% Cumulative in vitro drug released study of bare caraway essential oil and caraway nanogel in pH 6.8 PBS.

Figure 3

Percent cell-viability of bare caraway essential oil and caraway nanogel in HaCaT cells.

Figure 4

Time-kill assays of E. coli and S. aureus against caraway oil and caraway oil gel, where (a,b) are showing the effects of caraway oil and caraway oil-gel against E-coli respectively while, (c,d) are showing the assays of caraway oil and caraway oil-gel against S. aureus respectively.