In vitro antimicrobial properties of basil and thyme essential oils against Salmonella Spp.

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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Antifungal Activity of Aromatic Plants of the Lamiaceae Family in Bread

Foods ◽

10.3390/foods9111642 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1642

Author(s):

Adriana Skendi ◽

Dimitrios Ν. Katsantonis ◽

Paschalina Chatzopoulou ◽

Maria Irakli ◽

Maria Papageorgiou

Keyword(s):

Essential Oils ◽

Antimicrobial Properties ◽

Phytopathogenic Fungi ◽

Aromatic Plants ◽

Inhibitory Effects ◽

Antifungal Effect ◽

Aerial Parts ◽

Gas And Liquid Chromatography ◽

Main Components

The antifungal effect of aromatic plants (oregano, thyme, and Satureja) in dry form and as essential oils was evaluated in vitro (in potato dextrose agar (PDA)) and in bread against two phytopathogenic fungi found in food (Aspergillusniger and Penicillium). Gas and liquid chromatography were used to analyze essential oils attained by hydrodistillation of the aerial parts of the aromatic plants and of the dried plant aqueous solutions that were autoclaved for 20 min at 121 °C before analysis. Carvacrol, α-pinene, p-cymene, and γ-terpinene were the main components of the essential oils, whereas carvacrol, rosmarinic and caffeic acids were the main components of the water extracts. In vitro antifungal test results showed that the addition of plants in dry form had great antifungal potential against both fungal strains studied. Penicillium was more sensitive to the presence of aromatic plants than Aspergillus. Among the three plant species tested, thyme was the most potent antifungal against both fungi. For the bread product, all three aromatic plants studied showed inhibitory effects against both fungi. Results presented here suggest that oregano, thyme and Satureja incorporated in a bread recipe possess antimicrobial properties and are a potential source of antimicrobial ingredients for the food industry.

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Standardization of in-vitro methods for determination of antimicrobial properties of essential oils

Reviews in Medical Microbiology ◽

10.1097/mrm.0000000000000296 ◽

2021 ◽

Vol Publish Ahead of Print ◽

Author(s):

Iraj Rasooli ◽

Horieh Saderi ◽

Reza MohammadSalehi ◽

Masoud Dadashi ◽

Parviz Owlia

Keyword(s):

Essential Oils ◽

Antimicrobial Properties ◽

In Vitro Methods

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In-vitro antimicrobial efficacy of certian herbal seeds essential oils against important poultry microbes

Indian Journal of Animal Research ◽

10.18805/ijar.7089 ◽

2015 ◽

Author(s):

Darshana B. Bhaisare ◽

D. Thyagarajan ◽

R. Richard Churchil ◽

N. Punniamurthy

Keyword(s):

Staphylococcus Aureus ◽

Antiviral Activity ◽

Essential Oils ◽

Pasteurella Multocida ◽

Antimicrobial Properties ◽

Inhibition Zone ◽

Salmonella Typhi ◽

Fungal Species ◽

Diffusion Method

Two in-vitro experiments were conducted to evaluate the antibacterial, antifungal and antiviral properties of essential oil of herbal seeds. In-vitro antimicrobial properties of essential oils of phytobiotics was determined by disc diffusion method against Escherichia coli, Staphylococcus aureus, Pasteurella multocida and Salmonella typhi and two fungi namely Aspergillus fumigatus and Candida albicans. Thyme oil had statistically similar or significantly (P<0.05) higher inhibition zone against all the bacterial and fungal species compared to standard antibiotic, chloramphenicol or antifungal drug, nystatin. Fenugreek oil was not found to be active against microbes compared to control. Fennel and cumin oils had statistically similar or significantly (P<0.05) higher inhibition zone against all microbes except Staphylococcus aureus and Salmonella typhi compared to control. Antiviral activity of essential oils was determined by anti-NDV assay against New Castle disease virus (LaSota). The results indicated that essential oils of herbal seeds do not possess antiviral activity against NDV LaSota virus at 1mg/ml concentration.

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In Vitro Antimicrobial Activity of Lavender, Mint, and Rosemary Essential Oils and the Effect of Their Vapours on Growth of Penicillium spp. in a Bread Model System

Molecules ◽

10.3390/molecules26133859 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3859

Author(s):

Veronika Valková ◽

Hana Ďúranová ◽

Lucia Galovičová ◽

Nenad L. Vukovic ◽

Milena Vukic ◽

...

Keyword(s):

Essential Oils ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Antimicrobial Properties ◽

Antimicrobial Activities ◽

Minimal Inhibitory Concentrations ◽

Dpph Radical Scavenging ◽

Penicillium Spp

The chemical composition, antioxidant activity, and antimicrobial properties of three commercially available essential oils: rosemary (REO), lavender (LEO), and mint (MEO), were determined in the current study. Our data revealed that the major components of REO, MEO, and LEO were 1,8-cineole (40.4%), menthol (40.1%), and linalool acetate (35.0%), respectively. The highest DPPH radical-scavenging activity was identified in MEO (36.85 ± 0.49%) among the investigated EOs. Regarding antimicrobial activities, we found that LEO had the strongest inhibitory efficiencies against the growth of Pseudomonas aeruginosa and Candida (C.) tropicalis, MEO against Salmonella (S.) enterica, and REO against Staphylococcus (S.) aureus. The strongest antifungal activity was displayed by mint EO, which totally inhibited the growth of Penicillium (P.) expansum and P. crustosum in all concentrations; the growth of P. citrinum was completely suppressed only by the lowest MEO concentration. The lowest minimal inhibitory concentrations (MICs) against S. enterica, S. aureus, and C. krusei were assessed for MEO. In situ analysis on the bread model showed that 125 µL/L of REO exhibited the lowest mycelial growth inhibition (MGI) of P. citrinum, and 500 µL/L of MEO caused the highest MGI of P. crustosum. Our results allow us to make conclusion that the analysed EOs have promising potential for use as innovative agents in the storage of bakery products in order to extend their shelf-life.

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Antimicrobial potential of eucalyptus oil and lemongrass oil alone and in combination against clinical bacteria in planktonic and biofilm mode

World Journal of Biology and Biotechnology ◽

10.33865/wjb.006.02.429 ◽

2021 ◽

Vol 6 (2) ◽

pp. 21

Author(s):

Iram Liaqat ◽

Amna Asgar

Keyword(s):

Essential Oils ◽

Antimicrobial Properties ◽

Klebsiella Pneumonia ◽

Gram Negative Bacteria ◽

High Antimicrobial Activity ◽

Gram Positive Bacteria ◽

Natural Substances ◽

Volatile Products ◽

Different Strains

The use of natural substances has been trending from past few years. In recent years, the synthetic products obtained from plants have gained immense importance. Essential oils and volatile products obtained from plants are the source of food flavoring, aroma products and fragrance industries. Their use is also common to cure different ailments such as cancer, skin problems and nosocomial infections. Vast research has shown the antimicrobial properties of essential oils obtained from plants. Essential oils of lemongrass and eucalyptus have antiviral, antibacterial, antioxidant and insecticidal characteristics. Lemongrass and eucalyptus oils shows their antibacterial activity towards Gram positive bacteria such as Staphylococcus aureus, Bacillus subtilis and Gram-negative bacteria such as Escherichia coli and Klebsiella pneumonia. Combination of these oils also depicts high antimicrobial activity against different strains of bacteria. This review highlights the use of essential oils of lemongrass and eucalyptus for their in vitro antimicrobial properties against different bacteria in planktonic and biofilm mode. Mode of action by which the oil shows its inhibitory activity will be discussed. Susceptibility shown by different bacteria towards these essential oils and their components will be described

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In vitro activity of hybrid lavender essential oils against multidrug resistant strains of Pseudomonas aeruginosa

The Journal of Infection in Developing Countries ◽

10.3855/jidc.9920 ◽

2018 ◽

Vol 12 (01) ◽

pp. 009-014 ◽

Cited By ~ 9

Author(s):

Matthew Donadu ◽

Donatella Usai ◽

Antonio Pinna ◽

Tiziana Porcu ◽

Vittorio Mazzarello ◽

...

Keyword(s):

Antimicrobial Activity ◽

Essential Oils ◽

Cell Model ◽

Antimicrobial Properties ◽

The United States ◽

Multidrug Resistant ◽

New Antibiotics ◽

Mediterranean Regions ◽

A Cell

Introduction: Lavender is an evergreen shrub native to Northern Africa and other mountainous Mediterranean regions. It grows throughout Southern Europe, the United States, and Australia. Lavender essential oil has been used since ancient times and is known for its anti-inflammatory, antidepressant, antiseptic, antifungal and antimicrobial properties. Methodology: in this study, the antimicrobial activity of two Lavender essential oils (Lavanda sumian and Lavanda grosso) against 16 multidrug-resistant P. aeruginosa strains from clinical ocular samples taken from migrant patients has been investigated. The in vitro cytotoxic activity on human Wong-Kilbourne derivative (WKD) conjunctiva cells from healthy patients and nitric oxide synthase (NOS) activity on murine macrophage (J774.1A) were also evaluated. Results: L. sumian showed lower antimicrobial activity when compared to L. grosso. Both lavender oils tested had no cytotoxic effect at very low concentrations, mostly L. grosso. The essential oils extracted from L. sumian and L. grosso significantly reduced NOS in a cell model. Conclusion: Increase in drug resistance and lack of new antibiotics may encourage the development of natural antimicrobial treatments.

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Effects of essential oils of Rosmarinus officinalis Linn. and Origanum vulgare Linn. from different origins on Sporothrix brasiliensis and Sporothrix schenckii complex

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-4162-8962 ◽

2016 ◽

Vol 68 (4) ◽

pp. 991-999 ◽

Cited By ~ 2

Author(s):

S.B. Waller ◽

I.M. Madrid ◽

M.B. Cleff ◽

R. Santin ◽

R.A. Freitag ◽

...

Keyword(s):

Essential Oils ◽

Chemical Constituents ◽

Sporothrix Schenckii ◽

Antimicrobial Properties ◽

Rosmarinus Officinalis ◽

Origanum Vulgare ◽

Sporothrix Brasiliensis ◽

Commercial Oil

ABSTRACT Rosmarinus officinalis L. (rosemary) and Origanum vulgare L. (oregano) are known to have antimicrobial properties, but studies on sporotrichosis are scarce. This study aimed to evaluate the anti-Sporothrix spp. activity of essential oils from commercial products and oils extracted from aerial parts of these plants and analyze their chemical constituents. S. schenckii complex and S. brasiliensis (n: 25) isolated from humans, cats, dogs, and environmental soil were tested through M27-A3 guidelines of CLSI with modification for phytotherapics. The essential oils of R. officinalis L. were similar for MIC50 and MFC50 ≤2.25mg/mL for extracted oil; and 4.5mg/mL and 9mg/mL, respectively, for commercial oil. Both products showed MIC90 of 18mg/mL and MFC90 of 36mg/mL. In O. vulgare L., the extracted oil had better activity with MIC50 and MFC50 ≤2.25mg/mL, and MIC90 and MFC90 of 4.5mg/mL, whereas the commercial oil showed MIC50 and MFC50 of 9mg/mL and MIC90 18mg/mL, respectively, and MFC90 of 36mg/mL. Through gas chromatography (CG/FID), thymol and α-terpinene were majority for extracted oil of O. vulgare L., and carvacrol and γ-terpinene made up the majority of the commercial oil. Both essential oils of R. officinalis L. showed 1,8-cineole and α-pinene as major. The fungal isolates were susceptible to all tested essential oils, including in itraconazole-resistant S. brasiliensis isolates. The extracted and commercial oils of the plants presented in vitro anti-Sporothrix spp. activity, and they are promising for treatment of sporotrichosis, including in cases refractory to itraconazole. More studies should be performed about toxicity and in vivo efficacy for its safe use.

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Comparative in vitro efficacy of eight essential oils as antibacterial agents against pathogenic bacteria isolated from pet-turtles

Veterinární Medicína ◽

10.17221/142/2017-vetmed ◽

2018 ◽

Vol 63 (No. 7) ◽

pp. 335-343 ◽

Cited By ~ 1

Author(s):

BCJ De Silva ◽

S. Hossain ◽

SHMP Wimalasena ◽

HNKS Pathirana ◽

PS Dahanayake ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Essential Oils ◽

Pathogenic Bacteria ◽

Antibacterial Agents ◽

Bacterial Species ◽

Antimicrobial Properties ◽

Resistant Bacteria ◽

Antibiotic Resistant ◽

Drug Resistant Bacteria

Essential oils are plant extracts that have been used for their antimicrobial properties for centuries. The keeping of turtles as pets exhibits a growing trend worldwide but these animals are known to harbour a range of pathogenic bacteria. In the current study, we assessed eight essential oils as alternative antibacterial agents against nine species of pet turtle-borne Gram-negative bacteria, namely Aeromonas caviae, A. dhakensis, A. hydrophila, Citrobacter freundii, Morganella morganii, Proteus mirabilis, P. vulgaris, Pseudomonas aeruginosa and Salmonella enterica. Except for Pseudomonas aeruginosa, all other bacterial species showed high susceptibility to six essential oils, namely oregano, cinnamon, clove, lemongrass, lavender and eucalyptus oils in descending order of efficacy. Minimum inhibitory concentrations and minimum bactericidal concentrations values of the essential oils against all tested species except for P. aeruginosa showed low heterogeneity, showing that these essential oils can effectively control the growth of nearly all the tested. However, most of the tested bacteria were multiple-antibiotic-resistant as determined in the antibiotic disc diffusion test, with multiple-antibiotic-resistant index values of ≥ 0.2 for most of the strains. Therefore, with regards to their in vitro activity in controlling growth of multi-drug resistant bacteria, we can classify oregano, cinnamon, clove, lemongrass, lavender and eucalyptus essential oils as effective antibacterial agents. Thus, prospective application of these essential oils in controlling and treating these bacteria should be considered.

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Effects of phytogenics and organic acids alone and in combination on growth performance of weaned piglets

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200021037 ◽

2007 ◽

Vol 2007 ◽

pp. 200-200

Author(s):

T. Steiner ◽

C. Lückstädt

Keyword(s):

Organic Acids ◽

Essential Oils ◽

Growth Performance ◽

Antimicrobial Properties ◽

Nutrient Digestibility ◽

Growth Promoters ◽

Commercial Diet ◽

Beneficial Effects

Intensive research has been directed to the potential of Natural Growth Promoters (NGPs) to replace antibiotics. Phytogenics and organic acids (OA) have been shown to be effective in reducing the incidence of gastrointestinal disorders, thereby improving growth performance in pigs (Steiner, 2006). The addition of OA to nonruminant diets is supposed to have beneficial effects on feed safety since OA have a detrimental impact on moulds and other feed contaminants. Moreover, due to a decrease in gastric pH, acidification of the diets creates favourable conditions for nutrient digestibility, especially in young piglets (Radcliffe et al., 1998). Dietary supplementation with essential oils originating from aromatic plants may directly affect the intestinal microflora, both in quantitative and qualitative terms. As shown under in vitro (Helander et al., 1998) and in vivo conditions (Kroismayr et al., 2005), oregano essential oils have strong antimicrobial properties. Finally, it has been confirmed that addition of fructooligosaccharides (FOS) to diets for nonruminants may stabilize the gut microflora by selectively supporting the growth of beneficial bacteria (Macfarlane et al., 2006). Depending on individual farm conditions, a well-adjusted combination of different strategies is supposed to maximize the efficacy of NGPs in antibiotic-free feeding systems. The aim of the trial was to investigate the effects of phytogenics and OA alone and in combination in comparison with a commercial diet containing no additives.

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