Antifungal activity of essential oils against azole-resistant and azole-susceptible vaginal Candida glabrata strains

2018 ◽  
Vol 64 (10) ◽  
pp. 647-663 ◽  
Author(s):  
N. Massa ◽  
S. Cantamessa ◽  
G. Novello ◽  
E. Ranzato ◽  
S. Martinotti ◽  
...  
Keyword(s):  
Essential Oils ◽  
Candida Glabrata ◽  
Antimicrobial Agents ◽  
Cell Damage ◽  
Human Keratinocytes ◽  
Opportunistic Pathogen ◽  
Antifungal Drugs ◽  
Vaginal Candidiasis ◽  
Tea Tree ◽  
Different Strains

Candida glabrata is an opportunistic pathogen, associated with endocarditis, meningitis, and disseminated disease, and also with complicated vaginitis. Essential oils derived from aromatic plants are known in traditional medicine as antimicrobial agents and have antifungal properties. The aim of this work was to evaluate whether 12 tested essential oils (tea tree, laurel, anise, basil, bergamot, lavender, mint, oregano, grapefruit, rosemary, winter savory, and ginger) could have a transverse effect on C. glabrata sensitive strains but above all on strains resistant to the three main azole antifungals used (clotrimazole, fluconazole, itraconazole). For this reason, different strains of C. glabrata, vaginal isolated, were characterized (disk diffusion assay, minimal inhibitory concentration) with respect to their response to such antifungals. Electron microscopy analyses were performed to examine cellular damages in depth. Subsequently, we wanted to evaluate the effect of the oils on human cells to estimate their potential cytotoxicity. Oregano and winter savory were the two most effective essential oils, inducing growth inhibition, cell damage of C. glabrata strains (both sensitive and resistant to azole antifungal drugs), and medium–high level of toxicity against human keratinocytes. The results of this work support the research for new alternatives or complementary therapies against vaginal candidiasis.

scholarly journals In Vitro Efficacy of Essential Oils from Melaleuca Alternifolia and Rosmarinus Officinalis, Manuka Honey-based Gel, and Propolis as Antibacterial Agents Against Canine Staphylococcus Pseudintermedius Strains

Antibiotics ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 344
Author(s):  
Gabriele Meroni ◽  
Elena Cardin ◽  
Charlotte Rendina ◽  
Valentina Rafaela Herrera Millar ◽  
Joel Fernando Soares Filipe ◽  
...  
Keyword(s):  
Essential Oils ◽  
Antimicrobial Agents ◽  
Antibacterial Properties ◽  
Rosmarinus Officinalis ◽  
Diffusion Method ◽  
Melaleuca Alternifolia ◽  
Disk Diffusion Method ◽  
Staphylococcus Pseudintermedius ◽  
Tea Tree

Essential oils (EOs) and honeybee products (e.g., honey and propolis) are natural mixtures of different volatile compounds that are frequently used in traditional medicine and for pathogen eradication. The aim of this study was to evaluate the antibacterial properties of tea tree (Melaleuca alternifolia) EO (TTEO), Rosmarinus officinalis EO (ROEO), manuka-based gel, and propolis against 23 strains of Staphylococcus pseudintermedius (SP) isolated from canine pyoderma. Antimicrobial resistance screening was assessed using a panel of nine antimicrobial agents coupled with a PCR approach. An aromatogram was done for both EOs, using the disk diffusion method. The minimum inhibitory concentration (MIC) was determined for all the compounds. Among the 23 SP strains, 14 (60.9%) were multidrug-resistant (MDR), 11 strains (47.8%) were methicillin-resistant (MRSP), and 9 (39.1%) were non-MDR. The mean diameter of the inhibition zone for Melaleuca and Rosmarinus were 24.5 ± 8.8 mm and 15.2 ± 8.9 mm, respectively, resulting as statistically different (p = 0.0006). MIC values of TTEO and ROEO were similar (7.6 ± 3.2% and 8.9 ± 2.1%, respectively) and no statistical significances were found. Honeybee products showed lower MIC compared to those of EOs, 0.22 ± 0.1% for Manuka and 0.8 ± 0.5% for propolis. These findings reveal a significant antibacterial effect for all the tested products.

scholarly journals Essential oils and metal ions as alternative antimicrobial agents: a focus on tea tree oil and silver

2016 ◽  
Vol 14 (2) ◽  
pp. 369-384 ◽  
Author(s):  
Wan-Li Low ◽  
Ken Kenward ◽  
Stephen T Britland ◽  
Mohd CIM Amin ◽  
Claire Martin
Keyword(s):  
Essential Oils ◽  
Metal Ions ◽  
Antimicrobial Agents ◽  
Tea Tree Oil ◽  
Tea Tree

scholarly journals Treatment Strategies for Infected Wounds

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2392 ◽  
Author(s):  
Irina Negut ◽  
Valentina Grumezescu ◽  
Alexandru Grumezescu
Keyword(s):  
Essential Oils ◽  
Antimicrobial Agents ◽  
Bacterial Colonization ◽  
Healing Process ◽  
Treatment Strategies ◽  
Pharmaceutical Formulations ◽  
Multidrug Resistant ◽  
Wound Dressings ◽  
Therapeutic Effects ◽  
Tea Tree

The treatment of skin wounds is a key research domain owing to the important functional and aesthetic role of this tissue. When the skin is impaired, bacteria can soon infiltrate into underlying tissues which can lead to life-threatening infections. Consequently, effective treatments are necessary to deal with such pathological conditions. Recently, wound dressings loaded with antimicrobial agents have emerged as viable options to reduce wound bacterial colonization and infection, in order to improve the healing process. In this paper, we present an overview of the most prominent antibiotic-embedded wound dressings, as well as the limitations of their use. A promising, but still an underrated group of potential antibacterial agents that can be integrated into wound dressings are natural products, especially essential oils. Some of the most commonly used essential oils against multidrug-resistant microorganisms, such as tea tree, St. John’s Wort, lavender and oregano, together with their incorporation into wound dressings are presented. In addition, another natural product that exhibits encouraging antibacterial activity is honey. We highlight recent results of several studies carried out by researchers from different regions of the world on wound dressings impregnated with honey, with a special emphasis on Manuka honey. Finally, we highlight recent advances in using nanoparticles as platforms to increase the effect of pharmaceutical formulations aimed at wound healing. Silver, gold, and zinc nanoparticles alone or functionalized with diverse antimicrobial compounds have been integrated into wound dressings and demonstrated therapeutic effects on wounds.

scholarly journals Microbial glycoside hydrolases as antibiofilm agents with cross-kingdom activity

2017 ◽  
Author(s):  
Brendan D. Snarr ◽  
Perrin Baker ◽  
Natalie C. Bamford ◽  
Yukiko Sato ◽  
Hong Liu ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Mouse Model ◽  
Invasive Aspergillosis ◽  
Aspergillus Fumigatus ◽  
Antimicrobial Agents ◽  
Cell Damage ◽  
Antifungal Drugs ◽  
Glycoside Hydrolases ◽  
Intratracheal Administration

AbstractGalactosaminogalactan and Pel are cationic heteropolysaccharides produced by the opportunistic pathogens, Aspergillus fumigatus and Pseudomonas aeruginosa, respectively. These exopolysaccharides both contain 1,4-linked N-acetyl-D-galactosamine and play an important role in biofilm formation by these organisms. Proteins containing glycoside hydrolase domains have recently been identified within the biosynthetic pathway of each exopolysaccharide. Recombinant hydrolase domains from these proteins (Sph3h from A. fumigatus and PelAh from P. aeruginosa) were found to degrade their respective polysaccharides in vitro. We therefore hypothesized that these glycoside hydrolases could exhibit anti-biofilm activity, and further, given the chemical similarity between galactosaminogalactan and Pel, that they might display cross-species activity. Treatment of A. fumigatus with Sph3h disrupted A. fumigatus biofilms with an EC50 of 0.4 nM. PelAh treatment also disrupted pre-formed A. fumigatus biofilms with EC50 values similar to those obtained for Sph3h. In contrast, Sph3h was unable to disrupt P. aeruginosa Pel-based biofilms, despite being able to bind to the exopolysaccharide. Treatment of A. fumigatus hyphae with either Sph3h or PelAh significantly enhanced the activity of the antifungals posaconazole, amphotericin B and caspofungin, likely through increasing antifungal penetration of hyphae. Both enzymes were non-cytotoxic and protected A549 pulmonary epithelial cells from A. fumigatus-induced cell damage for up to 24 hours. Intratracheal administration of Sph3h was well tolerated, and reduced pulmonary fungal burden in a neutropenic mouse model of invasive aspergillosis. These findings suggest that glycoside hydrolases can exhibit activity against diverse microorganisms and may be useful as therapeutic agents by degrading biofilms and attenuating virulence.SignificanceThe production of biofilms is an important strategy used by both bacteria and fungi to colonize surfaces and to enhance resistance to killing by immune cells and antimicrobial agents. We demonstrate that glycoside hydrolases derived from the opportunistic fungus Aspergillus fumigatus and Gram-negative bacterium Pseudomonas aeruginosa can be exploited to disrupt pre-formed fungal biofilms and reduce virulence. Additionally, these glycoside hydrolases can be utilized to potentiate antifungal drugs by increasing their hyphal penetration, to protect human cells from fungal-induced injury and to attenuate virulence of A. fumigatus in a mouse model of invasive aspergillosis. The findings of this study identify recombinant microbial glycoside hydrolases as promising therapeutics with the potential for anti-biofilm activity against pathogens across different taxonomic kingdoms.

scholarly journals Antimicrobial activity of essential oils and fruits supplement in reduced nitrite salts condition

2017 ◽  
pp. 251-260
Author(s):  
Dragan Vujadinovic ◽  
Bojan Golic ◽  
Vladimir Tomovic ◽  
Vesna Gojkovic ◽  
Milan Vukic ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Natural Products ◽  
Essential Oils ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Model Systems ◽  
Aqueous Emulsion ◽  
Tea Tree ◽  
E Coli ◽  
Fruit Powder

Because of the growing negative perception of consumers related to the use of meat products produced by conventional curing methods, organic and natural products are increasingly accepted by consumers. Such products contain a large number of natural products derived from plants, spices, as well as their derivatives in form of essential oils, extracts, concentrates, and so on. These derivatives contain large number of active substances which are known to inhibit the metabolic processes of bacteria, yeasts and molds. Therefore, the goal of this paper was to investigate the synergistic antimicrobial activity of the models with a reduced presence of nitrite salt in aqueous solution, emulsions of essential oils in varying concentrations in vivo via antibiogram tests on pathogenic microorganisms. The effect of the six model groups was analyzed. Two groups were fruit powder solutions in concentrations of 0.2% to 1.2% (Acerola powder and fruit powder mix), while the other four groups were models of aqueous emulsion of essential oil in concentrations ranging from 0.05% to 1.2% (tea tree, clove, oregano, and cinnamon essential oils). In all models reduced amount of the sodium salt of 1.80%, 0.0075% nitrite salt and the liquid derivative as a natural source of the nitrate salt of 3% were used. Antibiogram tests were performed on five pathogenic bacteria (C. perfringens, E. coli, S. enterica, L. monocytogenes, and S. aureus). All antibiogram tests were performed according to Kirby-Bauer disk diffusion protocol. Results of antibiograms showed that without the presence of additional antimicrobial agents, in model systems with reduced content of salts, inhibition zones were not detected. Additionally, models with essential oils of tea tree oil and oregano had the widest inhibition zone diameters, ranging from 17.76?0.48mm for E. coli up to 42.50?0.13mm for S. aureus.

scholarly journals Antimicrobial testinas and gas chromatoaraphic analvsis of pure oxvaenated monoterpenes 1.8-cineole, α-terpineol, terpinen-4-ol and camphor as well as target comoounds in essential oils of pine (Pinus pinaster), rosemary (Rosmarinus officinalis), tea tree (Melaleuca alternifolia)

2005 ◽  
Vol 73 (1) ◽  
pp. 27-39 ◽  
Author(s):  
Leopold Jirovetz ◽  
Gerhard Buchbauer ◽  
Zapriana Denkova ◽  
Albena Stoyanova ◽  
Ivan Murgov ◽  
...  
Keyword(s):  
Essential Oils ◽  
Antimicrobial Activities ◽  
Aroma Compounds ◽  
Aroma Compound ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Tea Tree ◽  
Wide Range ◽  
Agar Dilution ◽  
Different Strains

The oxygenated monoterpenes 1,8-cineole, α-terpineol, terpinen-4-ol and camphor as well as essential oils of pine, rosemary and tea tree, rich in these volatiles, were tested for their antimicrobial activities against some different strains of yeast, Gram-(-)- and Gram-(+)-bacteria by agar diffusion and agar dilution method, respectively. The same was done using the phenolic aroma compound eugenol as a reference-substance. The monoterpene alcohols a-terpineol and terpinen-4-ol were found to be active against all strains used in a wide range. The same result was obtained for the testings of essential oils of pine, rosemary (2 samples) and tea tree. Nearly all aroma chemicals and essential oils did show a significant high antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. For qualitative and quantitaive investigations of the key aroma compounds and the compositions of the essential oils, gas chromatographic methods (GC-FID and GCMS with columns of different polarities) were used and the results correlated with that of the antimicrobial testings. The obtained data are discussed to get more insight into the influence of pure aroma compounds on antimicrobial activities of essential oils.

Antimicrobial Effects of Zataria multiflora and Ocimum basilicum on Escherichia coli O157:H7 During Ripening of Traditional Lighvan Cheese

2020 ◽  
Vol 16 (3) ◽  
pp. 373-380
Author(s):  
Mohammad B. Zendeh ◽  
Vadood Razavilar ◽  
Hamid Mirzaei ◽  
Khosrow Mohammadi
Keyword(s):  
Escherichia Coli ◽  
Essential Oils ◽  
Dairy Products ◽  
Antimicrobial Agents ◽  
Escherichia Coli O157 ◽  
Zataria Multiflora ◽  
Antimicrobial Effects ◽  
E Coli ◽  
Common Causes ◽  
Lighvan Cheese

Background: Escherichia coli O157:H7 is one of the most common causes of contamination in Lighvan cheese processing. Using from natural antimicrobial essential oils is applied method to decrease the rate of microbial contamination of dairy products. The present investigation was done to study the antimicrobial effects of Z. multiflora and O. basilicum essential oils on survival of E. coli O157:H7 during ripening of traditional Lighvan cheese. Methods: Leaves of the Z. multiflora and O. basilicum plants were subjected to the Clevenger apparatus. Concentrations of 0, 100 and 200 ppm of the Z. multiflora and 0, 50 and 100 ppm of O. basilicum essential oils and also 103 and 105 cfu/ml numbers of E. coli O157:H7 were used. The numbers of the E. coli O157:H7 bacteria were analyzed during the days 0, 30, 60 and 90 of the ripening period. Results: Z. multiflora and O. basilicum essential oils had considerable antimicrobial effects against E. coli O157:H7. Using the essential oils caused decrease in the numbers of E. coli O157:H7 bacteria in 90th days of ripening (P <0.05). Using from Z. multiflora at concentration of 200 ppm can reduce the survival of E. coli O157:H7 in Lighvan cheese. Conclusion: Using Z. multiflora and O. basilicum essential oils as good antimicrobial agents can reduce the risk of foodborne bacteria and especially E. coli O157:H7 in food products.

Aristolochia triangularis Cham. stems and leaves essential oils and their antimicrobial and antimycobacterial effects

2020 ◽  
Vol 10 ◽  
Author(s):  
Ionara I. Dalcol ◽  
Alessandra O. Pereira ◽  
Luisa H. Paz ◽  
Gabriela Benetti ◽  
Fallon S. Siqueira ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Essential Oils ◽  
Candida Glabrata ◽  
Skin Diseases ◽  
Enterobacter Aerogenes ◽  
Gas Chromatography Mass Spectrometry ◽  
Moderate Activity ◽  
Circulatory System Diseases ◽  
Germacrene D ◽  
Stems And Leaves

Background: Aristolochia triangularis Cham., popularly known as the "cipó-mil-homens", "angelicó" and "ypê-mi", is applied for the treatment of wounds, skin diseases (6,7), digestive and circulatory system diseases as an antipyretic and for malaria fever. Objective: In this work we investigated the chemical composition, the antimicrobial and antimycobacterial activities of the essential oils (EOs) extracted from A. triangularis fresh stems and leaves collected in Southern Brazil. Methods: Fresh stems and fresh leaves of Aristolochia triangularis Cham. were separately subjected to hydrodistillation using a Clevenger-type apparatus. The chemical composition of the essential oils (EOs) were analyzed by gas chromatography/mass spectrometry (GC/MS). The oil samples were evaluated for their antimycobacterial, antibacterial and antifungal activities against twenty-four microorganisms. Results: Hydrodistillation of fresh stems and leaves of A. triangularis resulted in 0.16% (w/w) and 0.37% (w/w) respectively of light-yellow oils. Germacrene D is found in 13.2 - 13.5% in both EOs. The constituent most abundant in the stems EO (19.18%) was the oxygenated diterpene ent-Kaur-16-en-19-al (10), along with E-nerolidol (17.89%). The main constituents of the leaves EO were bicyclogermacrene (24.79%), β-elemene (11.30%), E-caryophyllene (10.40%) and germacrene A (9.42%), in addition to the previously mentioned germacrene D. The stems and leaves EOs showed capacity to inhibit the Gram-negative Enterobacter aerogenes and the stems EO capacity to inhibit Staphylococcus aureus, with MIC values of 31.2 µg/mL. S. aureus was moderately sensitive to leaves EO, while stems EO displayed moderate activity against Enterococcus faecalis and Salmonella typhimurium (MIC values of 62.5 µg/mL). Candida glabrata was highly susceptible to both EOs (MIC values < 3.9 µg/mL). The EOs showed moderate potential to inhibit the growth of Cryptococcus gatti and Cryptococcus neoformans (MICs of 62.5 μg/mL). Conclusion: The A. triangularis essential oils from stems and leaves displayed capacity to inhibit Enterobacter aerogenes (MIC values of 31.2 µg/mL) and high antifungal effect against Candida glabrata (MIC values of <3.9 µg/mL). Mycobacterium massiliense and M. abscessus were susceptible to the leaves EO, with MICs of 39.06 μg/mL. These results showed the A. triangularis essential oils potential as antifungal and antimycobacterial to be used in the development of new antibiotic.

scholarly journals Chemical Compositions, Mosquito Larvicidal and Antimicrobial Activities of Essential Oils from Five Species of Cinnamomum Growing Wild in North Central Vietnam

Molecules ◽  
2020 ◽  
Vol 25 (6) ◽  
pp. 1303 ◽  
Author(s):  
Do N. Dai ◽  
Nguyen T. Chung ◽  
Le T. Huong ◽  
Nguyen H. Hung ◽  
Dao T.M. Chau ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Essential Oil ◽  
Essential Oils ◽  
Larvicidal Activity ◽  
Antimicrobial Agents ◽  
Chemical Compositions ◽  
North Central ◽  
Mosquito Larvicidal Activity ◽  
Central Vietnam ◽  
Leaf Essential Oil

Members of the genus Cinnamomum (Lauraceae) have aromatic volatiles in their leaves and bark and some species are commercially important herbs and spices. In this work, the essential oils from five species of Cinnamomum (C. damhaensis, C. longipetiolatum, C. ovatum, C. polyadelphum and C. tonkinense) growing wild in north central Vietnam were obtained by hydrodistillation, analyzed by gas chromatography and screened for antimicrobial and mosquito larvicidal activity. The leaf essential oil of C. tonkinense, rich in β-phellandrene (23.1%) and linalool (32.2%), showed excellent antimicrobial activity (MIC of 32 μg/mL against Enterococcus faecalis and Candida albicans) and larvicidal activity (24 h LC50 of 17.4 μg/mL on Aedes aegypti and 14.1 μg/mL against Culex quinquefasciatus). Cinnamomum polyadelphum leaf essential oil also showed notable antimicrobial activity against Gram-positive bacteria and mosquito larvicidal activity, attributable to relatively high concentrations of neral (11.7%) and geranial (16.6%). Thus, members of the genus Cinnamomum from Vietnam have shown promise as antimicrobial agents and as potential vector control agents for mosquitoes.

Sign in / Sign up

Export Citation Format

Share Document