Membrane Disruption Properties of Essential Oils—A Double-Edged Sword?

The emerging literature has suggested essential oils (EOs) as new possible weapons to fight antimicrobial resistance due to their inherent antimicrobial properties. However, the potential pharmaceutical use of EOs is confronted by several limitations, including being non-specific in terms of drug targeting, possessing a high cytotoxicity as well as posing a high risk for causing skin irritation. Furthermore, some EOs have been demonstrated to adversely affect the cellular lipid profiles and permeability of the cell membrane, which may result in undesirable outcomes for the cells. Nevertheless, owing to their naturally complex compositions, EOs still hold undiscovered potential to mitigate antimicrobial resistance, as an alternative to existing antibiotics. To address the issue of overuse in antibiotics for crops which have led to the growing threat of antimicrobial resistance globally, EOs have also been proposed as potential biopesticides. Since the perceived advantages of antimicrobial attributes in EOs remain largely unexplored, this review aims to provide a discourse into its current practical usefulness in the agricultural setting. Finally, updated bioengineering techniques with emphasis of the biopesticide potential of EOs as a means to alleviate antimicrobial resistance will be included.

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Application of essential oils as natural cosmetic preservatives

Herba Polonica ◽

10.2478/hepo-2013-0030 ◽

2013 ◽

Vol 59 (4) ◽

pp. 142-156 ◽

Cited By ~ 18

Author(s):

Mariola Dreger ◽

Karolina Wielgus

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Contact Allergy ◽

Skin Irritation ◽

Antimicrobial Properties ◽

Antimicrobial Effect ◽

Synergistic Activity ◽

Minimum Concentration ◽

Current State ◽

Risk Benefit Assessment

Abstract Nowadays, safety of chemical preservatives has been questioned by a big number of consumers. Traditionally used preservatives often cause skin irritation and lead to allergenic reactions. Growing demands for more natural and preservative-free cosmetics promoted an idea of the replacement of synthetic preservatives with essential oils (EOs) of antimicrobial properties. The antimicrobial effect of essential oil depends on content, concentration and interactions between the main active compounds. Effective preservatives should be characterized by a broad spectrum of antimicrobial activity at a minimum concentration. Formulations containing both types of preservatives: essential oil and a synthetic one have been tested and proposed as a compromise that allows for reducing concentration of both components due to their synergistic activity. Although most essential oils are regarded as safe, some of them may cause risk of contact allergy or phototoxic reaction. A well balanced risk-benefit assessment of essential oils is one of the great challenges for scientists or health policy authorities. This paper presents current state of knowledge on essential oils focused on their antimicrobial properties, the assessment of their efficacy and safety as cosmetic preservatives.

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Essential Oils: A Novel Approach for Anti-Microbial Therapy

The Natural Products Journal ◽

10.2174/2210315511666210906114009 ◽

2021 ◽

Vol 11 ◽

Author(s):

Ashwini Wani ◽

Hiren Mange ◽

Aishwarya Vasudevan

Keyword(s):

Antimicrobial Resistance ◽

Essential Oils ◽

Bacterial Infections ◽

Bacterial Resistance ◽

Antimicrobial Properties ◽

Rational Approach ◽

Ability To Act ◽

Novel Approach ◽

New Antibiotics ◽

Potential Applications

: Overexploitation of antibiotics has led to significant challenges with antimicrobial resistance. The gravity of this trend has resulted in the rapid emergence of multi-resistant pathogens. Increased frequency to treat infections and the unfeasibility to reverse this resistance have burdened researchers in developing novel mechanisms to counteract and obstruct antimicrobial resistance. An effective medical strategy to control resistance was to develop new and potent antibiotics although, a sobering reality is that the product pipeline towards new antibiotics is inadequate. To ensure continued effective treatment of bacterial infections, there is an urgent need to control as well as conserve existing antibiotics through novel approaches. Utilization of Essential Oils (EO) in a multi-target anti-infective therapy addresses this need by targeting the mechanism of bacterial resistance and discovering synergism between EO’s antimicrobial properties to anti-infectives. When introduced into a pharmaceutical formulation, this novel and rational approach will open the door towards the development of a new generation of antimicrobials. Today, several essential oils have the ability to act as resistant modifying agents and enhance the antimicrobial activity of anti-infectives. This review article intends to focus on the effectiveness of essential oils on drug-resistant pathogens, mechanisms to counteract antimicrobial resistance, approaches to enhance efficacy, and explore potential applications.

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Phytochemistry, Toxicology and Therapeutic Value of Petasites hybridus Subsp. Ochroleucus (Common Butterbur) from the Balkans

Plants ◽

10.3390/plants9060700 ◽

2020 ◽

Vol 9 (6) ◽

pp. 700

Author(s):

Tatjana Mihajilov-Krstev ◽

Boris Jovanović ◽

Bojan Zlatković ◽

Jelena Matejić ◽

Jelena Vitorović ◽

...

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Traditional Medicine ◽

Pyrrolizidine Alkaloids ◽

Sesquiterpene Lactones ◽

Skin Irritation ◽

Antimicrobial Properties ◽

Bacterial Strains ◽

The Balkans ◽

Anti Inflammatory

Petasites hybridus (Common butterbur) is extensively used in traditional medicine, and is currently gaining interest and popularity as a food supplement and for its medicinal properties. It contains a large number of active compounds of potential therapeutic activity, but also toxic pyrrolizidine alkaloids. Science-based information is needed to support the developing modern use of this plant, and to direct continued safe practice in traditional medicine. The present study focused on the essential oils from leaves and rhizomes of the understudied P. hybridus ssp. ochroleucus from the Balkans, and evaluated its phytochemistry and potential therapeutic activities (antimicrobial, antioxidant, anti-cholinesterase and anti-inflammatory), as well its toxicology potential (acute toxicity in insects and mice). We studied the essential oils, which are not commonly used in traditional practices, but have a potential for safe use since the toxic pyrrolizidine alkaloids, which are non-volatiles, are usually not present in the distilled essential oils. Pyrrolizidine alkaloids were indeed not detected in the essential oils; ingestion of the essential oils did not induce toxicity signs in mice, and topical application did not elicit skin irritation in humans. The essential oils had no antimicrobial properties against 20 pathogenic bacterial strains, but demonstrated good local anti-inflammatory activity in a Carrageenan-induced paw edema test. An insect toxicity test demonstrated that the leaf essential oil is an efficient insect repellent, and the demonstrated anti-cholinesterase activity suggests a potential for the treatment of neurological conditions. Isopetasin, a sesquiterpene found in plants of the genus Petasites, known to have anti-inflammatory effects, was present only in the rhizomes essential oil (3.9%), and sesquiterpene lactones concentrations were high, likely contributing to the antioxidant activity.

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Extraction of Essential Oils from Medicinal Plants and their Utilization as Food Antioxidants

Current Pharmaceutical Design ◽

10.2174/1381612826666200121092018 ◽

2020 ◽

Vol 26 (5) ◽

pp. 519-541 ◽

Cited By ~ 3

Author(s):

Giovanna Ferrentino ◽

Ksenia Morozova ◽

Christine Horn ◽

Matteo Scampicchio

Keyword(s):

Chemical Composition ◽

Medicinal Plants ◽

Beneficial Effect ◽

Essential Oils ◽

Bioactive Compounds ◽

Antimicrobial Properties ◽

Food Products ◽

Human Diseases ◽

Present Review ◽

Green Technologies

Background: The use of essential oils is receiving increasing attention worldwide, as these oils are good sources of several bioactive compounds. Nowadays essential oils are preferred over synthetic preservatives thanks to their antioxidant and antimicrobial properties. Several studies highlight the beneficial effect of essential oils extracted from medicinal plants to cure human diseases such as hypertension, diabetes, or obesity. However, to preserve their bioactivity, the use of appropriate extraction technologies is required. Method: The present review aims to describe the studies published so far on the essential oils focusing on their sources and chemical composition, the technologies used for their recovery and their application as antioxidants in food products. Results: The review has been structured in three parts. In the first part, the main compounds present in essential oils extracted from medicinal plants have been listed and described. In the second part, the most important technologies used for extraction and distillation, have been presented. In detail, conventional methods have been described and compared with innovative and green technologies. Finally, in the last part, the studies related to the application of essential oils as antioxidants in food products have been reviewed and the main findings discussed in detail. Conclusions: In summary, an overview of the aforementioned subjects is presented by discussing the results of the most recent published studies.

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Nanovesicles Loaded with Origanum onites and Satureja thymbra Essential Oils and Their Activity against Food-Borne Pathogens and Spoilage Microorganisms

Molecules ◽

10.3390/molecules26082124 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2124

Author(s):

Giulia Vanti ◽

Ekaterina-Michaela Tomou ◽

Dejan Stojković ◽

Ana Ćirić ◽

Anna Rita Bilia ◽

...

Keyword(s):

Essential Oils ◽

Propylene Glycol ◽

Antimicrobial Properties ◽

Spherical Shape ◽

Food Borne Pathogens ◽

Food Borne ◽

Spoilage Microorganisms ◽

Satureja Thymbra ◽

Origanum Onites

Food poisoning is a common cause of illness and death in developing countries. Essential oils (EOs) could be effective and safe natural preservatives to prevent and control bacterial contamination of foods. However, their high sensitivity and strong flavor limit their application and biological effectiveness. The aim of this study was firstly the chemical analysis and the antimicrobial evaluation of the EOs of Origanum onites L. and Satureja thymbra L. obtained from Symi island (Greece), and, secondly, the formulation of propylene glycol-nanovesicles loaded with these EOs to improve their antimicrobial properties. The EOs were analyzed by GC-MS and their chemical contents are presented herein. Different nanovesicles were formulated with small average sizes, high homogeneity, and optimal ζ-potential. Microscopic observation confirmed their small and spherical shape. Antibacterial and antifungal activities of the formulated EOs were evaluated against food-borne pathogens and spoilage microorganisms compared to pure EOs. Propylene glycol-nanovesicles loaded with O. onites EO were found to be the most active formulation against all tested strains. Additionally, in vitro studies on the HaCaT cell line showed that nanovesicles encapsulated with EOs had no toxic effect. The present study revealed that both EOs can be used as alternative sanitizers and preservatives in the food industry, and that their formulation in nanovesicles can provide a suitable approach as food-grade delivery system.

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Development of Advanced Textile Finishes Using Nano-Emulsions from Herbal Extracts for Organic Cotton Fabrics

Coatings ◽

10.3390/coatings11080939 ◽

2021 ◽

Vol 11 (8) ◽

pp. 939

Author(s):

Prabhuraj D. Venkatraman ◽

Usha Sayed ◽

Sneha Parte ◽

Swati Korgaonkar

Keyword(s):

Antimicrobial Resistance ◽

Antimicrobial Properties ◽

Coconut Oil ◽

Cotton Fabrics ◽

Batch Processes ◽

Herbal Extracts ◽

Organic Cotton ◽

Global Pandemic ◽

Nano Emulsion ◽

Sufficient Strength

The development of textile finishing with improved functional properties has been a growing interest among industry and scientists worldwide. The recent global pandemic also enhanced the awareness amongst many toward improved hygiene and the use of antimicrobial textiles. Generally, natural herbal components are known to possess antimicrobial properties which are green and eco-friendly. This research reports a novel and innovative method of developing and optimising nano-emulsions using two combinations of herbal extracts produced from Moringa oleifera, curry leaf, coconut oil (nano-emulsion 1) and other using Aegle marmelos with curry leaf and coconut oil (nano-emulsion 2). Nano-emulsions were optimised for their pH, thermal stability, and particle size, and percentage add-on. Organic cotton fabrics (20 and 60 gsm) were finished with nano-emulsions using continuous and batch processes and characterised for their surface morphology using scanning electron microscopy, energy dispersive X-ray (EDX) analysis and Fourier transform infrared spectroscopy (FTIR) analysis. The finished fabrics were evaluated for their Whiteness Index, assessed for antimicrobial resistance against Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) using AATCC 100 and 147 methods. In addition, fabrics were assessed for their antifungal efficacy (AATCC 30), tensile strength and air permeability. Results suggested that finished organic fabrics with nano-emulsions had antimicrobial resistance, antifungal, wash fastness after 20 washing cycles, and sufficient strength. This novel finishing method suggests that organic cotton fabrics treated with nano-emulsions can be used as a durable antimicrobial textile for healthcare and hygiene textiles.

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All-natural composite wound dressing films of essential oils encapsulated in sodium alginate with antimicrobial properties

International Journal of Pharmaceutics ◽

10.1016/j.ijpharm.2013.10.046 ◽

2014 ◽

Vol 463 (2) ◽

pp. 137-145 ◽

Cited By ~ 156

Author(s):

Ioannis Liakos ◽

Loris Rizzello ◽

David J. Scurr ◽

Pier Paolo Pompa ◽

Ilker S. Bayer ◽

...

Keyword(s):

Essential Oils ◽

Sodium Alginate ◽

Wound Dressing ◽

Antimicrobial Properties ◽

Natural Composite

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Essential Oils in Combination and Their Antimicrobial Properties

Molecules ◽

10.3390/molecules17043989 ◽

2012 ◽

Vol 17 (4) ◽

pp. 3989-4006 ◽

Cited By ~ 400

Author(s):

Imaël Henri Nestor Bassolé ◽

H. Rodolfo Juliani

Keyword(s):

Essential Oils ◽

Antimicrobial Properties

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Antimicrobial Activities in Pistacia atlantica—Aphids Make a Difference!

Proceedings ◽

10.3390/proceedings2020066009 ◽

2020 ◽

Vol 66 (1) ◽

pp. 9

Author(s):

Yoram Gerchman

Keyword(s):

Secondary Metabolites ◽

Essential Oils ◽

Organic Solvents ◽

Antimicrobial Properties ◽

Antimicrobial Activities ◽

Disk Diffusion ◽

Pistacia Atlantica ◽

Disk Diffusion Assay ◽

Bacteria And Fungi ◽

Diffusion Assay

Plants have been explored and used as sources for antimicrobial extract and compounds for many years, but galls—specialized structures forms on such by diversity of organisms—have been explored much less. Aphid galls host many insects in closed, humid and sugar rich environments for long periods. We have tested the antimicrobial properties of Slavum wertheimae aphid galls on Pistacia atlantica. Secondary metabolites were extracted from leaves and galls with organic solvents, and essential oils with Clevenger, and tested by disk diffusion assay and volatile effect on bacteria and fungi, respectively. The results demonstrated that gall extracts/essential oils had much stronger activity against the diversity of bacteria and fungi. The large diversity of galls suggest they could be explored as source for novel compounds.

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