Evaluation of Antibacterial Activity of Essential Oils and Their Combination against Multidrug-Resistant Bacteria Isolated from Skin Ulcer

Abstract

Background. Emerging of multidrug-resistant bacteria can compromise the effectiveness of antibiotics used to treat skin infections. Those bacteria imposed public health problems and questioning medical care in the 21st century. In this circumstance, essential oils of medicinal plants origin are supreme sources of structural and functionally divergent compounds, which inhibited the growth of common wound colonizing MRSA and ESBL producing P. aeruginosa. The aim of this study was to evaluate the combined antibacterial activity of essential oils extracted from Rumex abyssinicus, Cucumis pustulatus, and Discopodium penninervium against multidrug-resistant (MDR) isolates of skin ulcers. Methods. Essential oils (EOs) were extracted from aerial parts of R. abyssinicus, C. pustulatus, and D. penninervium with steam distillation. A mixture of each oil (1 : 1) was adsorbed to a disc and placed on Mueller Hinton Agar. Then, minimum zone of inhibition and bactericidal concentration of EOs was measured after incubeted for 18–24 hours at 37 °C. Their combined antibacterial effect was determined by the fractional inhibitory concentration index. Results. The antibacterial activity of mixed oil varied in their doses and bacteria species, of which a mixture of essential oil of R. abyssinicus and D. penninervium had inhibition zone (32 mm); its MIC and MBC values range from 1-2 μl/ml against MRSA. It had an inhibition zone (36 mm), MIC value 4 μl/ml, and MBC (8 μl/ml) against ESBL producing P. aeruginosa, whereas combined effects of R. abyssinicus and C. pustulatus had MIC values ranging from 2–8 μl/ml for E. coli and K. pneumoniae and 2 μl/ml for MRSA. There was a strong synergistic effect between R. abyssinicus and D. penninervium and promising antibacterial effect more specifically on MRSA and P. aeruginosa. Conclusion. This in vitro study of the combined effect of EOs has significant antibacterial activity on wound colonizing bacteria and reduces delaying wound healing as that of modern drugs tested in parallel. Hence, further structural elucidation of active compounds helps us to properly design or synthesis of topical antibiotics for wound care.

Evaluations of Antibacterial Properties of Zingiber purpureum Essential Oil Against 13 Different Gram-positive and Gram-negative Bacteria

“…(24,25) Gram-negative organisms are marginally less sensitive to oil-related contamination than Gram-positive bacteria due to the presence of hydrophilic lipopolysaccharides in their outer membrane that functions as a barrier to the hydrophobic compounds found in essential oils. (21)(22)(23) That result is contrary to our study which implies that the hydrophobic components of essential oils enable them to enter the periplasm of Gram-negative bacteria via porin proteins in the outer membrane. Bacterias which reported to have the lowest MIC scores are Gram-negative bacterias except S. aureus (Table 1).…”

“…Additionally, 6-and 12-gingerol showned antibacterial action against periodontal microorganisms. (21)(22)(23) According to previous studies, S. aureus, S. epidermidis, and S. mutans were more reactive to Z. purpureum oil than other bacteria, owing to the fact that Z.== purpureum oil contained 32 vol% terpinene-4-ol as the primary active compound and demonstrated activity against a broad range of Gram-positive bacteria. (24,25) Gram-negative organisms are marginally less sensitive to oil-related contamination than Gram-positive bacteria due to the presence of hydrophilic lipopolysaccharides in their outer membrane that functions as a barrier to the hydrophobic compounds found in essential oils.…”

The Phytochemical Tactics for Battling Antibiotic Resistance in Microbes: Secondary Metabolites and Nano Antibiotics Methods

“…Initially, attempts were made by Gadisa et al [46] to scientifically validate the antimicrobial potentials of plant essential oils, and it was reported that the essential oils of Cucumis pustulatus, Discopodium penninervium, and Rumex abyssinicus possessed promising antibacterial effects against multidrug-resistant pathogens that form colonies and cause wound infections, with methicillin-resistant Staphylococcus aureus being more prone to tested essential oils in either combination or alone. These findings supported previous findings that treatments derived from essential oils can destroy bacteria's cell walls, ultimately killing them.…”

Combination Strategies of Different Antimicrobials: An Efficient and Alternative Tool for Pathogen Inactivation

“…Recently, EO–EO associations showed a synergistic effect against vancomycin-resistant enterococci (VRE), methicillin-resistant S. aureus (MRSA), and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli [ 195 ]. A mixture of R. abyssinicus and D. penninervium EOs showed strong synergistic effects against MRSA and P. aeruginosa [ 206 ].…”