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Author Spotlight: An Antimicrobial Fabric Using Nano-Herbal Encapsulation of Essential Oils
Published on: April 7, 2023
Application of orange essential oil as an antistaphylococcal agent in a dressing model
Arunachalam Muthaiyan1, Debabrata Biswas, Philip G Crandall
1Center for Food Safety and Department of Food Science, University of Arkansas, Fayetteville, AR 72701, USA.
Background:
Staphylococcus aureus is the pathogen most often and prevalently involved in skin and soft tissue infections. In recent decades outbreaks of methicillin-resistant S. aureus (MRSA) have created major problems for skin therapy, and burn and wound care units. Topical antimicrobials are most important component of wound infection therapy. Alternative therapies are being sought for treatment of MRSA and one area of interest is the use of essential oils. With the increasing interest in the use and application of natural products, we screened the potential application of terpeneless cold pressed Valencia orange oil (CPV) for topical therapy against MRSA using an in vitro dressing model and skin keratinocyte cell culture model.
Methods:
The inhibitory effect of CPV was determined by disc diffusion vapor assay for MRSA and vancomycin intermediate-resistant S. aureus (VISA) strains. Antistaphylococcal effect of CPV in an in vitro dressing model was tested on S. aureus inoculated tryptic soya agar plate. Bactericidal effect of CPV on MRSA and VISA infected keratinocyte cells was examined by enumeration of extra- and intra-cellular bacterial cells at different treatment time points. Cytotoxic effects on human skin cells was tested by adding CPV to the keratinocyte (HEK001) cells grown in serum free KSFM media, and observed by phase-contrast microscope.
Results:
CPV vapour effectively inhibited the MRSA and VISA strains in both disc diffusion vapour assay and in vitro dressing model. Compared to untreated control addition of 0.1% CPV to MRSA infected keratinocyte decreased the viable MRSA cells by 2 log CFU/mL in 1 h and in VISA strain 3 log CFU/mL reduction was observed in 1 h. After 3 h viable S. aureus cells were not detected in the 0.2% CPV treatment. Bactericidal concentration of CPV did not show any cytotoxic effect on the human skin keratinocyte cells in vitro.
Conclusions:
At lower concentration addition of CPV to keratinocytes infected with MRSA and VISA rapidly killed the bacterial cells without causing any toxic effect to the keratinocytes. Therefore, the results of this study warrant further in vivo study to evaluate the potential of CPV as a topical antistaphylococcal agent.
Insights
Terpeneless cold pressed Valencia orange oil (CPV) effectively combats methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-intermediate resistant S. aureus (VISA) in vitro. This natural oil shows potential as a safe topical agent for skin infections, warranting further in vivo investigation.
Area of Science:
- Microbiology
- Dermatology
- Natural Products Chemistry
Background:
- Staphylococcus aureus is a primary cause of skin and soft tissue infections.
- Methicillin-resistant S. aureus (MRSA) outbreaks pose significant challenges in wound care.
- Essential oils are being explored as alternative topical antimicrobials against MRSA.
Purpose of the Study:
- To evaluate the topical therapeutic potential of terpeneless cold pressed Valencia orange oil (CPV) against MRSA.
- To assess the efficacy and safety of CPV using in vitro models.
Main Methods:
- Disc diffusion vapor assay and an in vitro dressing model were used to test CPV's inhibitory effect on MRSA and VISA.
- Bactericidal effects on infected keratinocyte cells were quantified.
- Cytotoxicity on human skin keratinocytes was evaluated.
Main Results:
- CPV vapor demonstrated significant inhibition of MRSA and VISA strains.
- Low concentrations of CPV (0.1-0.2%) rapidly reduced viable MRSA and VISA in keratinocytes.
- Effective concentrations of CPV exhibited no cytotoxic effects on human skin keratinocytes.
Conclusions:
- CPV rapidly kills MRSA and VISA in infected keratinocytes at low concentrations without toxicity.
- CPV shows promise as a topical antistaphylococcal agent.
- Further in vivo studies are recommended to validate CPV's therapeutic potential.
