Antimicrobial activities of plant essential oils and their components against antibiotic-susceptible and antibiotic-resistant foodborne pathogens

Essential oils (EO) are promising natural antimicrobial additives to control microbial pathogens. This study aims to investigate the antimicrobial activities of plant essential oils and to study the antimicrobial effect of oregano oil (OrO) in combination with food preservatives. The antimicrobial screening showed that Escherichia coli and Salmonella enterica subsp. enterica serovar Typhimurium (Salmonella ser. Typhimurium) appeared to be less susceptible to EO, whereas Staphylococcus aureus and Candida albicans were more affected. The Minimum Inhibitory Concentration (MIC) and Minimum Lethal Concentration (MLC) for laurel, cumin, oregano and rosemary oils showed values ranging from 0.078% to 1.25% (v/v). Also, synergic and viability effects of OrO combined with acetic acid (AcA) showed an additive effect against E. coli and C. albicans, while combination OrO + ascorbic acid (Asc) exhibited the same effect over Salmonella ser. Typhimurium and C. albicans. Therefore, oregano oil in combination with preservatives could be used to control the growth of pathogenic microorganisms for food preservation.

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Antimicrobial Activity of Nanodispersed Thymol in Tryptic Soy Broth

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-354 ◽

2013 ◽

Vol 76 (3) ◽

pp. 440-447 ◽

Cited By ~ 13

Author(s):

BHAVINI SHAH ◽

P. MICHAEL DAVIDSON ◽

QIXIN ZHONG

Keyword(s):

Antimicrobial Activity ◽

Foodborne Pathogens ◽

Water Solubility ◽

Optimal Growth ◽

Antimicrobial Activities ◽

Protein Isolate ◽

Effect Of Temperature ◽

Plant Essential Oils ◽

E Coli ◽

Hydrophobic Nature

Food safety is a continuing challenge for the food industry due to sporadic illness outbreaks caused by foodborne pathogens. Plant essential oils have been studied extensively as natural antimicrobials to control foodborne pathogens. However, their hydrophobic nature makes application in foods difficult because of their low water solubility, adverse impact on sensory quality, and binding with food components, which can interfere with antimicrobial efficacy. The objective of this study was to characterize antimicrobial activities of transparent nanodispersions of thymol encapsulated in whey protein isolate–maltodextrin conjugates, with comparison to free thymol. Tests were conducted for Escherichia coli O157:H7 strains ATCC 43889 and 43894, Salmonella Typhimurium strain 2576, Listeria monocytogenes strains Scott A and 101, and Staphylococcus aureus strains 27708 and SA113 in tryptic soy broth at various pHs and temperatures. Results indicate that the MIC for nanodispersed and free thymol against all strains of both gram-negative and gram-positive pathogens tested was 500 ppm at pH 6.8 and at the optimal growth temperature, with the exception of E. coli O157:H7 and L. monocytogenes strain Scott A, which were inhibited by 300 ppm of free thymol. Nanodispersed thymol was further tested at 500 ppm for inhibition of E. coli O157:H7 and L. monocytogenes at 35, 32, 25, and 4°C in tryptic soy broth adjusted to pH 5.5 and 3.5. At pH 5.5, L. monocytogenes was completely inhibited after 3 h, and E. coli O157:H7 showed a reduction of 1.0 to 3.0 log CFU/ml after 48 h. At pH 3.5, L. monocytogenes controls did not grow, but E. coli O157:H7 survived. At both pH 5.5 and 3.5, no significant effect of temperature on antimicrobial activity was observed at 500 mg/ml nanodispersed thymol. The present study demonstrated that transparent nanodispersions of thymol have promising antimicrobial activity against a broad spectrum of foodborne pathogens.

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Antimicrobial Activities of Starch-Based Biopolymers and Biocomposites Incorporated with Plant Essential Oils: A Review

Polymers ◽

10.3390/polym12102403 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2403 ◽

Cited By ~ 2

Author(s):

R. Syafiq ◽

S. M. Sapuan ◽

M. Y. M. Zuhri ◽

R. A. Ilyas ◽

A. Nazrin ◽

...

Keyword(s):

Antimicrobial Activity ◽

Tensile Strength ◽

Essential Oil ◽

Essential Oils ◽

Food Packaging ◽

Barrier Properties ◽

Antimicrobial Activities ◽

Food Storage ◽

Plant Essential Oils ◽

Bacteria And Fungi

Recently, many scientists and polymer engineers have been working on eco-friendly materials for starch-based food packaging purposes, which are based on biopolymers, due to the health and environmental issues caused by the non-biodegradable food packaging. However, to maintain food freshness and quality, it is necessary to choose the correct materials and packaging technologies. On the other hand, the starch-based film’s biggest flaws are high permeability to water vapor transfer and the ease of spoilage by bacteria and fungi. One of the several possibilities that are being extensively studied is the incorporation of essential oils (EOs) into the packaging material. The EOs used in food packaging films actively prevent inhibition of bacteria and fungi and have a positive effect on food storage. This work intended to present their mechanical and barrier properties, as well as the antimicrobial activity of anti-microbacterial agent reinforced starch composites for extending product shelf life. A better inhibition of zone of antimicrobial activity was observed with higher content of essential oil. Besides that, the mechanical properties of starch-based polymer was slightly decreased for tensile strength as the increasing of essential oil while elongation at break was increased. The increasing of essential oil would cause the reduction of the cohesion forces of polymer chain, creating heterogeneous matrix and subsequently lowering the tensile strength and increasing the elongation (E%) of the films. The present review demonstrated that the use of essential oil represents an interesting alternative for the production of active packaging and for the development of eco-friendly technologies.

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Antimicorbial Potency of Major Functional Foods’ Essential Oils in Liquid and Vapor Phases: A Short Review

Applied Sciences ◽

10.3390/app10228103 ◽

2020 ◽

Vol 10 (22) ◽

pp. 8103

Author(s):

Azam Amiri ◽

Javad Mottaghipisheh ◽

Fatemeh Jamshidi-Kia ◽

Karamatollah Saeidi ◽

Sara Vitalini ◽

...

Keyword(s):

Essential Oils ◽

Food Processing ◽

Allyl Isothiocyanate ◽

Short Review ◽

Antimicrobial Activities ◽

Food Preservation ◽

Plant Essential Oils ◽

Increasing Risk ◽

Common Plant ◽

Liquid And Vapor Phases

Due to the increasing risk of chemical contaminations in the application of synthetic fungicides, the use of plant essential oils and extracts has recently been increased. In the present review, the antimicrobial potential of the most active plant-food essential oils in liquid and vapor phases has been reviewed. The volatile isothiocyanates, aldehydes, and phenols, including allyl isothiocyanate, carvacrol, thymol, and eugenol, are considered to be the predominant components of essential oils, possessing significant antimicrobial activities. These components alone or in mixture can be effective. Overall, the antimicrobial activity of aroma compounds depends on the plant species, concentration, and method of application. This review provides useful information about the inhibitory application of the most common plant-foods’ essential oils in liquid and vapor phases against the growth of pathogenic microorganisms. Essential oils (EOs) are promising natural antimicrobial alternatives in food processing facilities. Although the food industry primarily uses spices and herbs to impart flavor, aroma, and pungency to foods, potent EOs represent interesting sources of natural products for food preservation.

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Composition and Antimicrobial Properties of Sardinian Juniperus Essential Oils against Foodborne Pathogens and Spoilage Microorganisms

Journal of Food Protection ◽

10.4315/0362-028x-66.7.1288 ◽

2003 ◽

Vol 66 (7) ◽

pp. 1288-1291 ◽

Cited By ~ 34

Author(s):

SOFIA COSENTINO ◽

ANDREA BARRA ◽

BARBARA PISANO ◽

MADDALENA CABIZZA ◽

FILIPPO MARIA PIRISI ◽

...

Keyword(s):

Essential Oils ◽

Foodborne Pathogens ◽

Antimicrobial Properties ◽

Antimicrobial Activities ◽

Aflatoxin Contamination ◽

Gas Chromatography Mass Spectrometry ◽

Chemical Compositions ◽

Microdilution Method ◽

Ms Analysis ◽

Broth Microdilution Method

In this work, the chemical compositions and antimicrobial properties of Juniperus essential oils and of their main components were determined. Five berry essential oils obtained from different species of Juniperus growing wild in Sardinia were analyzed. The components of the essential oils were identified by gas chromatography–mass spectrometry (GC-MS) analysis. The antimicrobial activities of the oils and their components against food spoilage and pathogenic microorganisms were determined by a broth microdilution method. The GC-MS analysis showed a certain variability in the concentrations of the main constituents of the oils. α-Pinene was largely predominant in the oils of the species J. phoenicea subsp. turbinata and J. oxycedrus. α-Pinene and myrcene constituted the bulk (67.56%) of the essential oil of J. communis. Significant quantitative differences were observed for myrcene, δ-3-carene, and d-germacrene. The results of the antimicrobial assay show that the oils of J. communis and J. oxycedrus failed to inhibit any of the microorganisms at the highest concentrations tested (MLC ≥ 900 μg/ml), while the oils extracted from J. turbinata specimens were active against fungi, particularly against a strain of Aspergillus flavus (an aflatoxin B1 producer). Of the single compounds tested, δ-3-carene was found to possess the broadest spectrum of activity and appeared to contribute significantly to the antifungal activity observed for J. turbinata oils. This activity may be helpful in the prevention of aflatoxin contamination for many foods.

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Sodium Polyphosphate and Polyethylenimine Enhance the Antimicrobial Activities of Plant Essential Oils

ScienceOpen Research ◽

10.14293/s2199-1006.1.sor-life.z72tp0.v1 ◽

2016 ◽

Author(s):

Heidi Weinkauf ◽

Byron Brehm-Stecher

Keyword(s):

Essential Oils ◽

Antimicrobial Activities ◽

Microbial Pathogens ◽

Human Pathogens ◽

Intrinsic Resistance ◽

Sodium Polyphosphate ◽

Plant Essential Oils ◽

Food Contact Surfaces ◽

Rough Strain ◽

Effective Use

Plant extracts have been used for millennia for treatment of disease, with much recent interest focusing on the antimicrobial activities of plant essential oils (EOs). Although EOs are active against common microbial pathogens, their effective use as topical, environmental or food antimicrobials will require EO-based formulations with enhanced antimicrobial activities. In the present study, two polyionic compounds, sodium polyphosphate (polyP, a polyanion) and polyethylenimine (PEI, a polycation), were evaluated for their abilities to enhance the antimicrobial activities of six EOs against the human pathogens Escherichia coli O157:H7, Salmonella enterica subsp. enterica ser Minnesota, Pseudomonas aeruginosa, Listeria monocytogenes, Staphylococcus aureus and Candida albicans. EOs tested were cinnamon, clove, regular and redistilled oregano and two types of thyme oil. EOs were examined via disk diffusion and broth microdilution, either alone or in the presence of sub-inhibitory levels of polyP or PEI. Both polyP and PEI were found to be effective enhancers of EO activity against all strains examined, and calculation of fractional inhibitory indices for select EO/organism pairings demonstrated that true synergy was possible with this enhancement approach. Experiments with a deep rough strain of S. Minnesota probed the role of the outer membrane in both intrinsic resistance to EOs and enhancement by polyions. The use of polyP and PEI for boosting the antimicrobial activities of EOs may eventually facilitate the development of more effective EO-based antimicrobial treatments for use in applications such as wound treatment, surface disinfection, or as GRAS antimicrobials for use in foods or on food contact surfaces.

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Synergistic Antimicrobial Activities of Thai Household Essential Oils in Chitosan Film

Polymers ◽

10.3390/polym13091519 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1519

Author(s):

Juthamas Tantala ◽

Pornchai Rachtanapun ◽

Chitsiri Rachtanapun

Keyword(s):

Essential Oils ◽

Foodborne Pathogens ◽

Pathogenic Bacteria ◽

Transmission Rate ◽

Antibacterial Properties ◽

Meat Products ◽

Chitosan Film ◽

Antimicrobial Activities ◽

Post Process ◽

Chitosan Films

Foodborne pathogens mostly contaminate ready-to-eat (RTE) meat products by post-process contamination and cause foodborne disease outbreaks. Preventing post-process contamination and controlling microbial growth during storage by packing the RTE meats with active antimicrobial film from chitosan combined with the synergism of Thai household essential oils was investigated. Here, we analyzed antimicrobial activity and mechanical properties of chitosan films incorporated with essential oil of fingerroot (EOF) and holy basil (EOH) based on their fractional inhibitory concentration and isobolograms. We showed that antimicrobial activities of chitosan film and chitosan films formulated with EOF:EOH displayed a dramatical reduction of Listeria monocytogenes Scott A concentration by 7 Log in 12 h. Chitosan film incorporated with EOF:EOH at ratio 0.04:0.04% v/v/w strongly retarded growth of total viable count of L. monocytogenes on vacuum-packed bologna slices during seven days of storage at 4 and 10 °C. Combined EOF and EOH added to chitosan films did not alter thickness, elongation (%) and colors (L*, a* and b*) of the chitosan film, but it increased water vapor transmission rate and decreased film tensile strength. Results suggested that chitosan film had strong antibacterial properties. Its effectiveness in inhibiting foodborne pathogenic bacteria in ready-to-eat meat products was enhanced by adding a combination of EOF:EOH.

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Chemical composition and antimicrobial activity of essential oils from selected herbs cultivated in the South of Brazil against food spoilage and foodborne pathogens

Ciência Rural ◽

10.1590/s0103-84782012000700026 ◽

2012 ◽

Vol 42 (7) ◽

pp. 1300-1306 ◽

Cited By ~ 33

Author(s):

Sheila Mello da Silveira ◽

Anildo Cunha Júnior ◽

Gerson Neudí Scheuermann ◽

Fábio Luiz Secchi ◽

Cleide Rosana Werneck Vieira

Keyword(s):

Antimicrobial Activity ◽

Chemical Composition ◽

Essential Oils ◽

Foodborne Pathogens ◽

Disc Diffusion ◽

Bacterial Strains ◽

Plant Essential Oils ◽

Agar Disc ◽

Cymbopogon Flexuosus ◽

South Of Brazil

The chemical composition of 10 selected plant essential oils obtained by steam distillation was determined by GC and GC/MS. The antimicrobial activity of the essential oils was screened against 12 important food-related bacterial strains by agar disc-diffusion assay. MIC and MBC were determined for the essential oils that presented the highest activity in the agar disc-diffusion test. The most active essential oils against the tested bacteria were, in descending order, lemongrass (Cymbopogon flexuosus), basil (Ocimum basilicum), oregano (Origanum vulgare), cinnamon leaf (Cinnamomum zeylanicum), and laurel (Laurus nobilis). Except for S. Typhimurium, the tested bateria were inhibited at MIC values lower or equal to 0.62mg mL-1 by lemongrass (Cymbopogon flexuosus) essential oil. Yersinia enterocolitica presented the highest sensitivity to all essential oils tested (CMI≤0.62mg mL-1). There was a significant correlation (P<0.05) between oxygenated monoterpenes levels in the essential oils and MIC and MBC values against Escherichia coli. Results showed that the evaluated essential oils present high potential as natural preservatives.

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Plant Phytochemicals in Food Preservation: Antifungal Bioactivity: A Review

Journal of Food Protection ◽

10.4315/0362-028x.jfp-19-163 ◽

2019 ◽

Vol 83 (1) ◽

pp. 163-171 ◽

Cited By ~ 6

Author(s):

SAÚL REDONDO-BLANCO ◽

JAVIER FERNÁNDEZ ◽

SARA LÓPEZ-IBÁÑEZ ◽

ELISA M. MIGUÉLEZ ◽

CLAUDIO J. VILLAR ◽

...

Keyword(s):

Essential Oils ◽

Fruits And Vegetables ◽

Food Additives ◽

Pathogenic Fungi ◽

Antimicrobial Activities ◽

Food Preservation ◽

Food Spoilage ◽

Aromatic Plants ◽

Plant Essential Oils ◽

Broad Array

ABSTRACT Synthetic food additives generate a negative perception in consumers. This fact generates an important pressure on food manufacturers, searching for safer natural alternatives. Phytochemicals (such as polyphenols and thiols) and plant essential oils (terpenoids) possess antimicrobial activities that are able to prevent food spoilage due to fungi (e.g., Aspergillus, Penicillium) and intoxications (due to mycotoxins), both of which are important economic and health problems worldwide. This review summarizes industrially interesting antifungal bioactivities from the three main types of plant nutraceuticals: terpenoids (as thymol), polyphenols (as resveratrol) and thiols (as allicin) as well as some of the mechanisms of action. These phytochemicals are widely distributed in fruits and vegetables and are very useful in food preservation as they inhibit growth of important spoilage and pathogenic fungi, affecting especially mycelial growth and germination. Terpenoids and essential oils are the most abundant group of secondary metabolites found in plant extracts, especially in common aromatic plants, but polyphenols are a more remarkable group of bioactive compounds as they show a broad array of bioactivities. HIGHLIGHTS

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