Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add more filters










Type of study
Publication year range
1.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-823929

ABSTRACT

Objective: To examine the effect of Rumex crispus (R. crispus) and Rumex sanguineus (R. sanguineus) plant extracts against isolates of Acinetobacter baumannii (A. baumannii) from wounds, including multidrug-resistant strains.Methods: Six prepared Rumex extracts were subjected to liquid chromatography-tandem mass spectrometry. Antimicrobial activity of extracts and pure compounds (catechin, quercetin, isoquercitrin, emodin, and gallic acid) was examined by a microtiter plate method, while for determination of compound binary combinations activity a checkerboard method was applied. Active fractions of extracts were detected by agar-overlay high-performance thin-layer chromatography-bioautography assay followed by liquid chromatography - diode array detection - mass spectrometry analysis. Results: A total of 28 compounds were detected in two extracts of R. crispus and 26 compounds in four different R. sanguineus extracts, with catechin as a dominant component. Anti-A. baumannii activity was confirmed for all six R. sanguineus and R. crispus extracts at the concentration range from 1 to 4 mg/mL. Neither examined single compounds nor their binary combinations exhibited an anti-A. baumannii activity (MIC>256 μg/mL). The bioautography showed that fractions with the most prominent anti-A. baumannii activity tended to contain more polar compounds, predominantly flavonol (quercetin and kaempherol) glycosides; but also fractions containing flavanone (eriodictyol) glycosides and anthraquinone (emodin) glycosides; and less polar eriodictyol aglycone. Conclusions: The results justify and elucidate the traditional application of R. sanguineus and R. crispus extracts for wound healing, indicating the necessity for their further examination in combat against multidrug-resistant A. baumannii isolates from wounds.

2.
J Ethnopharmacol ; 178: 125-36, 2016 Feb 03.
Article in English | MEDLINE | ID: mdl-26671210

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional herbal medicine has become an important issue on the global scale during the past decade. Among drugs of natural origin, special place belongs to essential oils, known as strong antimicrobial agents that can be used to combat antibiotic-resistant bacteria. Eucalyptus camaldulensis leaves are traditional herbal remedy used for various purposes, including treatment of infections. The aim of this study was to determine antimicrobial potential of two E. camaldulensis essential oils against multi-drug resistant (MDR) Acinetobacter baumannii wound isolates and to examine possible interactions of essential oils with conventional antimicrobial agents. MATERIALS AND METHODS: Chemical composition of essential oils was determined by gas chromatography-mass spectrometry analysis (GC-MS). MIC values of essential oils against A. baumannii strains were estimated by modified broth microdilution method. The components responsible for antimicrobial activity were detected by bioautographic analysis. The potential synergy between the essential oils and antibiotics (ciprofloxacin, gentamicin and polymyxin B) was examined by checkerboard method and time kill curve. RESULTS: The dominant components of both essential oils were spatulenol, cryptone, p-cimene, 1,8-cineole, terpinen-4-ol and ß-pinene. The detected MICs for the E. camaldulensis essential oils were in range from 0.5 to 2 µl mL(-1). The bioautographic assay confirmed antibacterial activity of polar terpene compounds. In combination with conventional antibiotics (ciprofloxacin, gentamicin and polymyxin B), the examined essential oils showed synergistic antibacterial effect in most of the cases, while in some even re-sensitized MDR A. baumannii strains. The synergistic interaction was confirmed by time-kill curves for E. camaldulensis essential oil and polymyxin B combination which reduced bacterial count under detection limit very fast, i.e. after 6h of incubation. CONCLUSIONS: The detected anti-A. baumannii activity of E. camaldulensis essential oils justifies traditional use of this plant. The proven E. camaldulensis essential oil synergistic interactions with conventional antibiotics could lead to the development of new treatment strategies of infections caused by MDR A. baumannii strains in the term of antibiotic dose reduction.


Subject(s)
Acinetobacter baumannii/drug effects , Anti-Infective Agents/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Eucalyptus/chemistry , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Anti-Bacterial Agents/pharmacology , Bicyclic Monoterpenes , Bridged Bicyclo Compounds/pharmacology , Ciprofloxacin/pharmacology , Cyclohexanols/pharmacology , Cymenes , Drug Interactions/physiology , Eucalyptol , Microbial Sensitivity Tests/instrumentation , Monoterpenes/pharmacology , Polymyxin B/pharmacology , Terpenes/pharmacology
3.
Phytother Res ; 30(3): 476-84, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26686190

ABSTRACT

Essential oils possess strong antimicrobial activity, even against multiresistant Helicobacter pylori. Available therapies against H. pylori infection have multiple disadvantages, indicating a great need for a development of new therapeutics. The purpose of this study was to develop a potent natural product based anti-H. pylori formulation. First, anti-H. pylori activity of nine essential oils was determined, after which the most active oils were mixed in various ratios for further testing. Satureja hortensis, Origanum vulgare subsp. vulgare and O. vulgare subsp. hirtum essential oils expressed the highest activity (MIC = 2 µL mL(-1)). Their binary and ternary mixtures exhibited notably higher antimicrobial activity (MIC ≤ 2 µL mL(-1)). The most active was the mixture of S. hortensis and O. vulgare subsp. hirtum oils in volume ratio 2:1, which expressed 4 times higher activity than individual oils (MIC = 0.5 µL mL(-1)). According to GC-MS, both oils in the mixture were characterized by high content of phenols (48-73%), with carvacrol as the main carrier of antimicrobial activity. Presented in vitro study pointed out binary mixture of S. hortensis and O. vulgare subsp. hirtum essential oils in volume ratio 2:1 as promising candidate for further in vivo studies targeting H. pylori infection.


Subject(s)
Anti-Bacterial Agents/pharmacology , Helicobacter pylori/drug effects , Monoterpenes/pharmacology , Oils, Volatile/pharmacology , Origanum/chemistry , Plant Extracts/pharmacology , Satureja/chemistry , Cymenes , Drug Combinations , Drug Synergism , Gas Chromatography-Mass Spectrometry , Helicobacter Infections/drug therapy , Helicobacter Infections/microbiology , Monoterpenes/analysis , Oils, Volatile/chemistry , Phenols/analysis , Phenols/pharmacology , Plant Extracts/chemistry , Plant Oils/chemistry , Plant Oils/pharmacology
4.
Phytomedicine ; 21(12): 1666-74, 2014 Oct 15.
Article in English | MEDLINE | ID: mdl-25442275

ABSTRACT

Acinetobacter baumannii is a rapidly emerging, highly resistant clinical pathogen with increasing prevalence. In recent years, the limited number of antimicrobial agents available for treatment of infections with multi-drug resistant (MDR) strains reinforced tendency for discovery of novel antimicrobial agents or treatment strategies. The aim of the study was to determine antimicrobial effectiveness of three Myrtus communis L. essential oils, both alone and in combination with conventional antibiotics, against MDR A. baumannii wound isolates. The results obtained highlighted the occurrence of good antibacterial effect of myrtle oils when administered alone. Using checkerboard method, the combinations of subinhibitory concentrations of myrtle essential oils and conventional antibiotics, i.e. polymixin B and ciprofloxacine were examined. The results proved synergism among M. communis L. essential oils and both antibiotics against MDR A. baumannii wound isolates, with a FIC index under or equal 0.50. Combination of subinhibitory concentrations of essential oils and ciprofloxacin most frequently reduced bacterial growth in synergistic manner. The similar has been shown for combination with polymyxin B; furthermore, the myrtle essential oil resulted in re-sensitization of the MDR wound isolates, i.e. MICs used in combination were below the cut off for the sensitivity to the antibiotic. Time-kill curve method confirmed efficacy of myrtle essential oil and polymyxin B combination, with complete reduction of bacterial count after 6h. The detected synergy offers an opportunity for future development of treatment strategies for potentially lethal wound infections caused by MDR A. baumannii.


Subject(s)
Acinetobacter baumannii/drug effects , Drug Resistance, Multiple, Bacterial , Myrtus/chemistry , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Anti-Bacterial Agents/pharmacology , Ciprofloxacin/pharmacology , Drug Synergism , Gas Chromatography-Mass Spectrometry , Microbial Sensitivity Tests , Oils, Volatile/chemistry , Plant Leaves/chemistry , Plant Oils/chemistry , Polymyxin B/pharmacology
5.
Microbiol Res ; 169(4): 240-54, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24291016

ABSTRACT

Since synthetic antimicrobial agents and food additives can cause a number of adverse effects, there is a growing interest from consumers in ingredients from natural sources. Medicinal plants, such as Myrtus communis L. are a source of new compounds which can be used in both the food industry and for medical purposes, primarily as antimicrobial agents. In this review, the characteristics of myrtle essential oils and extracts are summarized, with particular attention to their chemical composition, biological activities and potential applications.


Subject(s)
Anti-Infective Agents/pharmacology , Antioxidants/pharmacology , Myrtus/chemistry , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Antioxidants/chemistry , Antioxidants/isolation & purification , Oils, Volatile/isolation & purification , Plant Extracts/isolation & purification
6.
Res Microbiol ; 164(1): 55-60, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23000091

ABSTRACT

Pseudomonas aeruginosa is a highly resistant opportunistic pathogen and an important etiological agent of various types of infections. During the last decade, P. aeruginosa phages have been extensively examined as alternative antimicrobial agents. The aim of the study was to determine antimicrobial effectiveness of combining subinhibitory concentrations of gentamicin, ceftriaxone, ciprofloxacin or polymyxin B with P. aeruginosa-specific bacteriophages belonging to families Podoviridae and Siphoviridae. The time-kill curve method showed that a combination of bacteriophages and subinhibitory concentrations of ceftriaxone generally reduced bacterial growth, and synergism was proven for a Siphoviridae phage σ-1 after 300 min of incubation. The detected alteration in morphology after ceftriaxone application, resulting in cell elongation, along with its specific mode of action, seemed to be a necessary but was not a sufficient reason for phage-antibiotic synergism. The phenomenon offers an opportunity for future development of treatment strategies for potentially lethal infections caused by P. aeruginosa.


Subject(s)
Anti-Bacterial Agents/pharmacology , Pseudomonas Phages/physiology , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/virology , Microbial Sensitivity Tests , Pseudomonas aeruginosa/growth & development
7.
Lasers Med Sci ; 25(4): 559-69, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20186556

ABSTRACT

Although the use of high-level Er:YAG laser irradiation has been increasing in periodontal and peri-implant therapy, the effects of low-level Er:YAG laser on surrounding tissues and cells remain unclear. In the present study, the effects of low-level Er:YAG laser irradiation on osteoblast proliferation were investigated. Cells of the osteoblastic cell line MC3T3-E1 were treated with low-level Er:YAG laser irradiation with various combinations of laser settings (fluence 0.7-17.2 J/cm(2)) and in the absence or presence of culture medium during irradiation. On day 1 and/or day 3, cell proliferation and death were determined by cell counting and by measurement of lactate dehydrogenase (LDH) levels. Further, the role of mitogen-activated protein kinase (MAPK) pathways in laser-enhanced cell proliferation was investigated by inhibiting the MAPK pathways and then measuring MAPK phosphorylation by Western blotting. Higher proliferation rates were found with various combinations of irradiation parameters on days 1 and 3. Significantly higher proliferation was also observed in laser-irradiated MC3T3-E1 cells at a fluence of approximately 1.0-15.1 J/cm(2), whereas no increase in LDH activity was observed. Further, low-level Er:YAG irradiation induced the phosphorylation of extracellular signal-regulated protein kinase (MAPK/ERK) 5 to 30 min after irradiation. Although MAPK/ERK 1/2 inhibitor U0126 significantly inhibited laser-enhanced cell proliferation, activation of stress-activated protein kinases/Jun N-terminal kinase (SAPK/JNK) and p38 MAPK was not clearly detected. These results suggest that low-level Er:YAG laser irradiation increases osteoblast proliferation mainly by activation of MAPK/ERK, suggesting that the Er:YAG laser may be able to promote bone healing following periodontal and peri-implant therapy.


Subject(s)
Extracellular Signal-Regulated MAP Kinases/metabolism , Lasers, Solid-State , Low-Level Light Therapy , Mitogen-Activated Protein Kinases/metabolism , Osteoblasts/radiation effects , Animals , Blotting, Western , Cell Death/radiation effects , Cell Line , Cell Proliferation/radiation effects , JNK Mitogen-Activated Protein Kinases/metabolism , L-Lactate Dehydrogenase/metabolism , Mice , Osteoblasts/cytology , Phosphorylation , p38 Mitogen-Activated Protein Kinases/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...