scholarly journals Potential of bacteriophages as disinfectants to control of Staphylococcus aureus biofilms

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jun Song ◽  
Hongri Ruan ◽  
Li Chen ◽  
Yuqi Jin ◽  
Jiasan Zheng ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Organic Materials ◽  
Tap Water ◽  
Full Activity ◽  
Narrow Spectrum ◽  
Mammary Gland Tissue ◽  
Nonionic Detergent ◽  
Biofilm Structure ◽  
And Control ◽  
Nonionic Detergents

Abstract Background Staphylococcus aureus is the causative agent of chronic mastitis, and can form a biofilm that is difficult to completely remove once formed. Disinfectants are effective against S. aureus, but their activity is easily affected by environmental factors and they are corrosive to equipment and chemically toxic to livestock and humans. Therefore, we investigated the potential utility of a bacteriophage as a narrow-spectrum disinfectant against biofilms formed by S. aureus. In this study, we isolated and characterized bacteriophage vB_SauM_SDQ (abbreviated to SDQ) to determine its efficacy in removing S. aureus biofilms. Results SDQ belongs to the family Myoviridae and consists of a hexagonal head, long neck, and short tail. This phage can sterilize a 109 CFU/mL culture of S. aureus in 12 h and multiply itself 1000-fold in that time. Biofilms formed on polystyrene, milk, and mammary-gland tissue were significantly reduced after SDQ treatment. Fluorescence microscopy and scanning electron microscopy showed that SDQ destroyed the biofilm structure. Moreover, the titer of SDQ remained relatively high after the lysis of the bacteria and the removal of the biofilm, exerting a continuous bacteriostatic effect. SDQ also retained its full activity under conditions that mimic common environments, i.e., in the presence of nonionic detergents, tap water, or organic materials. A nonionic detergent (Triton X-100) enhanced the removal of biofilm by SDQ. Conclusions Our results suggest that SDQ, a specific lytic S. aureus phage, can be used to control biofilm infections. SDQ maintains its full activity in the presence of nonionic detergents, tap water, metal chelators, and organic materials, and can be used in combination with detergents. We propose this phage as a narrow-spectrum disinfectant against S. aureus, to augment or supplement the use of broad-spectrum disinfectants in the prevention and control of the mastitis and dairy industry contamination caused by S. aureus.

The effect of anionic and nonionic detergents on soil microfungi

1970 ◽  
Vol 48 (3) ◽  
pp. 583-589 ◽  
Author(s):  
Benny K. H. Lee
Keyword(s):  
Growth Rates ◽  
Dominant Species ◽  
Tap Water ◽  
Dry Weight ◽  
Control Soil ◽  
Treated Soil ◽  
Nonionic Detergent ◽  
Soil Microfungi ◽  
Nonionic Detergents

Surveys of the microfungal populations in potting soil watered with tap water, a solution of anionic 15-S-3A detergent (Tergitol, 15-S-3A), and a solution of nonionic 15-S-9 detergent (Tergitol, 15-S-9), revealed a greater reduction in propagule densities in the anionic detergent watered soil than in the nonionic detergent watered soil. In the anionic detergent study, 39 species, including six dominant species which contributed 58% of the isolates, were obtained from the treated soil. In the nonionic detergent study, both sample populations contained 29 species and the four to six dominants contributed 67–68% of the 100 isolates.Twenty-two isolates representing 10 dominant species were tested in vitro for sensitivity to the two detergents. All grew at the lowest concentration (10 p.p.m.) of both detergents. The growth rates of nine isolates increased with the addition of 10 p.p.m. of the anionic detergent; four isolates showed increased growth with 10 p.p.m. of the nonionic detergent. With increasing concentration of detergent from 100 to 1000 p.p.m., the growth rates of 21 of the 22 fungi decreased. Isolates recovered from detergent-treated soil grew better in the medium containing detergent than the same species recovered from the control soil. In concentrations of 1000 p.p.m., complete inhibition was displayed by four species in the anionic series compared to five species in the nonionic series. Both detergents affected pigmentation, exudate formation, and rigidity of the sporangiophore in several of the fungi.Fourteen of the 16 isolates tested used anionic detergent and 12 isolates used nonionic detergent as a carbon source for growth. Dry weight differences indicated that the anionic detergent was more available than the nonionic detergent.

Properties and control of cold-induced small colony variants of Staphylococcus aureus

2020 ◽  
pp. 100874
Author(s):  
Jiaju Qiao ◽  
Mengjiao Zhu ◽  
Yun Fan ◽  
Zhaoxin Lu ◽  
Fengxia Lv ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Small Colony Variants ◽  
Small Colony ◽  
And Control

scholarly journals Real-Time In Vivo Bioluminescent Imaging for Evaluating the Efficacy of Antibiotics in a Rat Staphylococcus aureus Endocarditis Model

2005 ◽  
Vol 49 (1) ◽  
pp. 380-387 ◽  
Author(s):  
Yan Q. Xiong ◽  
Julie Willard ◽  
Jagath L. Kadurugamuwa ◽  
Jun Yu ◽  
Kevin P. Francis ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Real Time ◽  
Imaging System ◽  
Bioluminescent Imaging ◽  
Vancomycin Therapy ◽  
Treatment Groups ◽  
Highly Sensitive ◽  
Relevant Animal Model ◽  
And Control

ABSTRACT Therapeutic options for invasive Staphylococcus aureus infections have become limited due to rising antimicrobial resistance, making relevant animal model testing of new candidate agents more crucial than ever. In the present studies, a rat model of aortic infective endocarditis (IE) caused by a bioluminescently engineered, biofilm-positive S. aureus strain was used to evaluate real-time antibiotic efficacy directly. This strain was vancomycin and cefazolin susceptible but gentamicin resistant. Bioluminescence was detected and quantified daily in antibiotic-treated and control animals with IE, using a highly sensitive in vivo imaging system (IVIS). Persistent and increasing cardiac bioluminescent signals (BLS) were observed in untreated animals. Three days of vancomycin therapy caused significant reductions in both cardiac BLS (>10-fold versus control) and S. aureus densities in cardiac vegetations (P < 0.005 versus control). However, 3 days after discontinuation of vancomycin therapy, a greater than threefold increase in cardiac BLS was observed, indicating relapsing IE (which was confirmed by quantitative culture). Cefazolin resulted in modest decreases in cardiac BLS and bacterial densities. These microbiologic and cardiac BLS differences during therapy correlated with a longer time-above-MIC for vancomycin (>12 h) than for cefazolin (∼4 h). Gentamicin caused neither a reduction in cardiac S. aureus densities nor a reduction in BLS. There were significant correlations between cardiac BLS and S. aureus densities in vegetations in all treatment groups. These data suggest that bioluminescent imaging provides a substantial advance in the real-time monitoring of the efficacy of therapy of invasive S. aureus infections in live animals.

THE UPTAKE OF TRITIATED LYSINE VASOPRESSIN BY RAT AND PIG PITUITARY NEURAL LOBES IN VITRO

1971 ◽  
Vol 50 (4) ◽  
pp. 669-677 ◽  
Author(s):  
B. A. EDWARDS
Keyword(s):  
Tap Water ◽  
Exchange Chromatography ◽  
Control Group ◽  
Breakdown Product ◽  
Nacl Solution ◽  
Water Control ◽  
Neural Lobe ◽  
Lysine Vasopressin ◽  
And Control

SUMMARY Uptake of tritiated lysine vasopressin ([3H]LVP) was studied in halved neural lobes of rats (which had been given either tap water (control group) or 2% (w/v) NaCl solution as drinking water for 4 days) as well as in slices of pig neural lobe. Uptake of radioactivity into the neural lobes was shown but analysis of the extracts of incubated lobes of both species by ion exchange chromatography showed that very little of it remained in the tissue as hormone. In addition, some radioactivity was associated with trichloroacetic acid-insoluble proteins. After 90 min of incubation, and after correction for the breakdown, the uptake of unchanged [3H]LVP, expressed as a tissue: medium ratio, was 0·14 ± 0·04 and 0·09 ± 0·03 (mean ± s.e.m.) for the saline-treated and control rats respectively, while the tissue: medium ratios for the breakdown product(s) were 6·47 ± 0·45 and 5·50 ± 0·36. The results suggest uptake of [3H]LVP into the cell with almost complete intracellular breakdown of the hormone.

Enhancement of iron availability by some organic materials

1979 ◽  
Vol 93 (1) ◽  
pp. 115-120 ◽  
Author(s):  
A. A. Parsa ◽  
A. Wallace ◽  
J. P. Martin
Keyword(s):  
Calcareous Soil ◽  
Dry Matter ◽  
Organic Materials ◽  
Iron Availability ◽  
Lawsonia Inermis ◽  
Plant Materials ◽  
Phenolic Substances ◽  
And Control ◽  
Layer Chromatography ◽  
Positive Effect

SUMMARYIn a preliminary laboratory experiment in Iran, not reported here, 5 out of 30 plant materials incorporated into a highly calcareous soil had a positive effect on increasing the DTPA- (diethylenetriaminepentaacetic acid)-extractable Fe and all except one significantly increased the vegetative growth of sorghum. The plant materials included Lawsonia inermis L., Malva silvestris L., Zyzyphus nummularia Wak. and Lavandula carnopifolia L. A glasshouse study was repeated with two California soils pretreated with 0·5% Fe2O3 to determine if these organic materials have practical value in making Fe available to plants. A calcareous, Fe-deficient Hacienda (fine-loamy, mixed, thermic aquic natrargid) and a non-calcareous Yolo (fine-silty, mixed, non-acid, thermic typic xerothents). The previously mentioned organic materials and Laminaria saccharina L. (Lamour) were incorporated into the soils at two rates, 15000 and 20000μg/g, as air dry and in ash form. An adequate supply of major and micronutrients other than Fe was ensured. Other treatments included 5 μg Fe/g as FeSO4, Fe-138 chelate and control. All of the plant materials with the exception of L. carnopifolia significantly increased dry-matter yield and Fe, Zn, Cu and Mn uptake by sorghum in the Hacienda soil. In the Yolo soil the above were not significant. Thin-layer chromatography of the extracts of the plant materials revealed the presence of significant quantities of phenolic substances.

scholarly journals Antimicrobial Effect of Plasma-Activated Tap Water on Staphylococcus aureus, Escherichia coli, and Candida albicans

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1480
Author(s):  
William Chiappim ◽  
Aline da Graça Sampaio ◽  
Felipe Miranda ◽  
Mariana Fraga ◽  
Gilberto Petraconi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Tap Water ◽  
Antimicrobial Effect ◽  
Gliding Arc ◽  
Oxidation Reduction ◽  
Treatment Conditions ◽  
Oxidation Reduction Potential

In this study, the potential antimicrobial activity of plasma-activated tap water (PAW) was evaluated against Staphylococcus aureus, Escherichia coli, and Candida albicans. For this, PAW was prepared in a gliding arc plasma system using two treatment conditions: stagnant water and water stirring by a magnetic stirrer, called moving water. Subsequently, their oxidation-reduction potential (ORP), pH, electrical conductivity (σ), and total dissolved solids (TDS) were monitored in different areas of the sample divided according to the depth of the beaker. It was observed that PAW obtained in dynamic conditions showed a more uniform acidity among the evaluated areas with pH 3.53 and ORP of 215 mV. Finally, standardized suspensions of Staphylococcus aureus (ATCC 6538), Escherichia coli (ATCC 10799), and Candida albicans (SC 5314) were treated with PAW, and the reduction of viable cells determined the antimicrobial effect. Our results indicate that the tap water, activated by plasma treatment using gliding arc, is an excellent inactivation agent in the case of Staphylococcus aureus and Escherichia coli. On the other hand, no significant antimicrobial activity was achieved for Candida albicans.

scholarly journals Perfil Epidemiológico dos Isolamentos dos Microrganismos ‘Problema’

2019 ◽  
Vol 32 (9) ◽  
pp. 600
Author(s):  
Pedro Atilano Carvalho ◽  
Ana Monteiro ◽  
Bruno Almeida ◽  
Filomena Horta Correia ◽  
Vera Resende ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Beta Lactamase ◽  
Drug Resistant ◽  
Streptococcus Pneumonia ◽  
Extended Spectrum Beta Lactamase ◽  
The North ◽  
Male Patients ◽  
Epidemiological Profile ◽  
Healthcare Associated ◽  
And Control

Introduction: Infections are a major problem and the presence of drug-resistant microorganisms has significant clinical and economic impact. The present study aims to evaluate the epidemiological profile of “problem” microorganisms isolated in a hospital in the north of Portugal.Material and Methods: All isolated microorganisms were analyzed, between January 2014 and June 2015. Data obtained was then processed using statistical software.Results: We analyzed 8146 microbiological isolations and found a prevalence of 23% of ‘problem’ microorganisms (in descending order of frequency: Enterococcus, Pseudomonas, Staphylococcus aureus e Streptococcus pneumonia), 57.55% of which isolated in male patients. The most frequent mechanism of drug resistance for the overall sample was the production of extended-spectrum beta-lactamase, and resistance to oxacillin for ‘problem’ microorganisms.Discussion: In this sample, we observed a much higher prevalence of ‘problem’ microorganisms than that reported in other countries, which shows the need of improvement of surveillance mechanisms and treatment of these cases. Microorganisms that showed higher resistance were Staphylococcus aureus (resistant to oxacillin) and Enterococcus (resistant to vancomycin). Those were isolated in patients with a higher mean age compared to non-resistant microorganisms. Most of these microorganisms were isolated in hospitalized patients or intermediate and intensive care units, what relates them with healthcare associated infections.Conclusion: The prevalence of infection by ‘problem’ microorganisms during the studied period was 23%. The detection and control of the spread of these microorganisms are paramount due to its impact on health costs, morbidity and survival of patients.

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