scholarly journals Isolation and Characterization of Bacillus subtilis MP56 with Antimicrobial Activity against MDR (Multi Drug Resistant) Strains

2013 ◽  
Vol 49 (1) ◽  
pp. 90-94 ◽  
Author(s):  
Sungyong Park ◽  
Jincheol Yoo ◽  
Chinam Seong ◽  
Seungsik Cho
Keyword(s):  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Drug Resistant ◽  
Isolation And Characterization ◽  
Resistant Strains ◽  
Drug Resistant Strains

Characterization of biofilms in drug-sensitive and drug-resistant strains ofCandida albicans

2013 ◽  
Vol 25 (2) ◽  
pp. 87-95 ◽  
Author(s):  
Elisabetta Vavala ◽  
Marisa Colone ◽  
Claudio Passariello ◽  
Ignacio Celestino ◽  
Laura Toccacieli ◽  
...  
Keyword(s):  
Drug Resistant ◽  
Ofcandida Albicans ◽  
Resistant Strains ◽  
Drug Resistant Strains

Screening and Characterization of Soil Microbes Producing Antimicrobial Compounds in Makkah Province, Saudi Arabia

2021 ◽  
Vol 18 (4) ◽  
pp. 719-732
Author(s):  
Najwa Menwer Alharbi ◽  
Amjad Khalid Alharthi ◽  
Alsamadani Alsamadani ◽  
Raneem Ahmed Almihmadi ◽  
Bothaina Ali Alaidaroos
Keyword(s):  
Antimicrobial Activity ◽  
Soil Microorganisms ◽  
Likelihood Method ◽  
Diffusion Method ◽  
Group Method ◽  
Drug Resistant ◽  
Antimicrobial Compounds ◽  
Resistant Strains ◽  
Inhibition Zones ◽  
Drug Resistant Strains

This study aimed to investigate a method to manage antimicrobial resistance (AMR) issues by exploring soil microorganisms that are capable of producing bioactive compounds. Eight different types of soil were selected from three locations to screen, isolate, and identify microorganisms that are capable of producing antimicrobial compounds. The multi-drug resistant strains are Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans were selected for primary and secondary screening using the crowded plate method and the agar well diffusion method. Inhibition zones were measured, and data were assessed using statistical tests to check for normality and differences between parametric variables and nonparametric data. This was followed by biochemical characterization, DNA isolation, and polymerase chain reaction (PCR). Molecular identification was performed using 16S rRNA amplification and sequencing. Here, 86 isolates containing bacteria and fungi were successfully extracted from soil samples. Further, 49 of 86 microbes showed possible antimicrobial activity, but only 12 isolates resulted in distinct inhibition zones with the selected multi-drug resistant strains. The following different taxa were identified: Firmicutes (nine strains), Proteobacteria (one strain), Actinobacteria (one strain), and Azotobacter (one strain). Species are represented in a phylogenetic tree, which was constructed using the unweighted pair-group method with arithmetic mean (UPGMA) method. The evolutionary distances were computed using the Maximum Composite Likelihood method. The identified microorganisms showed antimicrobial activity, confirming that soil microorganisms have great potential to address AMR issues.

IBS Therapeutic has Broad Spectrum Antimicrobial Activity

2021 ◽  
Author(s):  
Ashley L. Cunningham ◽  
Orhi Esarte Palomero ◽  
Bradley J. Voss ◽  
M. Stephen Trent ◽  
Bryan W. Davies
Keyword(s):  
Antimicrobial Activity ◽  
Irritable Bowel Syndrome ◽  
Broad Spectrum ◽  
Enteric Pathogens ◽  
Drug Resistant ◽  
Antibacterial And Antifungal Activity ◽  
Resistant Strains ◽  
Irritable Bowel ◽  
Antibacterial And Antifungal ◽  
Drug Resistant Strains

Otilonium bromide is a poorly absorbed oral medication used to control irritable bowel syndrome. It is thought to act as a muscle relaxant in the intestine. Here we show that otilonium bromide has broad-spectrum antibacterial and antifungal activity, including against multi-drug resistant strains. Our results suggest otilonium bromide could act on enteric pathogens and may offer a new scaffold for poorly absorbed intestinal antimicrobial therapy.

scholarly journals Morphologic characterization of Mycobacterium tuberculosis circulating strains in a Lisbon hospital.

2013 ◽  
Vol 19 (S4) ◽  
pp. 11-12
Author(s):  
C. Silva ◽  
E. Alverca ◽  
A.P. Alves de Matos ◽  
P.A. Carvalho ◽  
I. Portugal ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mycobacterium Tuberculosis ◽  
Cell Envelope ◽  
Drug Susceptibility ◽  
Drug Resistant ◽  
Lowenstein Jensen ◽  
Resistant Strains ◽  
Drug Resistant Strains ◽  
Surface Figure

Tuberculosis (TB) is one of the major causes of mortality and morbidity worldwide accounting for 3.1 million deaths per year. This disease, caused by Mycobacterium tuberculosis (M. tuberculosis) made a deadly comeback, during the 1990’s, triggered mainly by the emergence of acquired immunodeficiency syndrome (AIDS). More recently, the emergence of multidrug resistant (MDR) and extensively drug resistant (XDR) M. tuberculosis strains, uncovered the most freighting face of this disease an incurable infection with the currently available therapeutic tools. Although Portugal is considered a medium incidence setting, annually are reported MDR and even XDR TB cases. The majority of these cases occur in the Lisbon area and the strains involved are genetically related being known as Lisboa family.In the present work a group of 283 M. tuberculosis isolates collected in a Lisbon hospital during a two years period (2008-2009) were studied. The morphology of colonies grown on Lowenstein-Jensen slants was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) using previously described procedures. The aim of the study was the establishment of a link between mycobacteria drug susceptibility and structure. In the first part of the study approximately 20 isolates, with different drug susceptibility profiles ranging from pan-susceptible to XDR, were grown on Lowenstein-Jensen slants and their morphology was compared. Although all mycobacteria originated rough colonies their size differ with the drug susceptibility profile. The pan-susceptible strains generated larger colonies than drug resistant strains as shown in figure 1.These colonies were then processed for SEM analysis. The results obtained show that mycobacteria surface are distinct in susceptible and drug resistant strains as shown in figure 2.A and B. While drug susceptible mycobacteria have a homogenous surface (Figure 1A), drug resistant bacteria present a heterogeneous surface (Figure 2B) with small protrusions (Fig. 2B inset). In order to evaluate the existence of differences in the ultrastructure of circulating M. tuberculosis strains the colonies were processed and analysed by TEM. For this approach were selected only two isolates: the pan-susceptible R188/09 and the XDR HPV108/09.The results obtained by the analysis of at least 300 bacteria present in non consecutive sections show that mycobacteria cell width (0 350 nm) is similar for both bacteria (Table 1). Nevertheless, their cell length and cell envelope width are significantly different. The XDR strain is shorter (p=0.009) and has a ticker cell envelope (p=0.004) than the pan-susceptible strain. These results are in agreement with those published in the literature.Altogether our data clearly shows the existence of a link between mycobacteria ultrastructure and drug susceptibility. In order to better evaluate these differences a larger number of isolates must be studied. The use of other electron microscopy techniques, such as CEMOVIS, will avoid the formation of undesirable artefacts (e.g. mesosome) produced by dehydration and room temperature sectioning allowing a better characterization of mycobacteria ultrastructure.The authors acknowledge the funding by Fundação para a Ciência e Tecnologia (SFRH/BD/73579/2010, C2008-C2008_P2 and PEst-OE/CTM-UI0084/2011 grants.)

scholarly journals Potentiation of antimicrobial activity of colistin with antibiotics of different groups against multidrug- and extensively drug-resistant strains of Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa

2020 ◽  
Vol 22 (2) ◽  
pp. 128-136
Author(s):  
Dmitry V. Tapalskiy ◽  
T.A. Petrovskaya ◽  
A.I. Kozlova ◽  
Mikhail V. Edelstein
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Klebsiella Pneumoniae ◽  
Acinetobacter Baumannii ◽  
Bactericidal Activity ◽  
Drug Resistant ◽  
Extensively Drug Resistant ◽  
Potentiation Effect ◽  
Resistant Strains ◽  
Drug Resistant Strains

Objective. To reveal antibiotics being capable of potentiating the antimicrobial activity of colistin against multidrug- and extensively drug-resistant strains of Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa. Materials and Methods. The minimum inhibitory concentrations (MIC) of colistin alone and in combination with fixed concentrations of antibiotics of different groups were determined for 272 multidrug- and extensively drug-resistant strains of K. pneumoniae, A. baumannii and P. aeruginosa. Bactericidal activity of colistin, carbapenems, clarithromycin and their combinations were also determined at fixed PK/PD breakpoint concentrations of antibiotics. Results. Potentiation of colistin antibacterial activity in the presence of fixed concentration of rifampicin (0.5 mg/L) was observed as a 4–16-fold MIC decrease for K. pneumoniae and A. baumannii. In the presence of fixed concentrations of azithromycin (2 mg/L) or clarithromycin (1 mg/L), the colistin MICs decreased 64–512 times for K. pneumoniae, 4–32 times for A. baumannii, 16–64 times for P. aeruginosa. Two- or more-fold reduction of MIC of colistin in the presence of 1 mg/L clarithromycin was observed for 85.2% of K. pneumoniae, 86.3% of A. baumannii and 60.2% of P. aeruginosa strains. In the presence of 1 mg/L clarithromycin and 8 mg/L meropenem, the potentiation effect was enhanced and was observed for an even larger percent of isolates: 96.1% K. pneumoniae, 98.0% A. baumannii and 61.3% P. aeruginosa. Colistin-based combinations with clarithromycin-meropenem and clarithromycin-doripenem were bactericidal against most isolates of A. baumannii and P. aeruginosa (91.4–100%), and against colistin-sensitive K. pneumoniae (95.3%) and colistin-resistant K. pneumoniae (79.1%). Conclusions. The ability of macrolides to significantly potentiate the colistin antimicrobial activity against both colistin-sensitive and colistin-resistant strains of K. pneumoniae, A. baumannii and P. aeruginosa was shown. This potentiation effect was enhanced in the presence of carbapenems. The most potent bactericidal activity was revealed with dual and triple combinations of colistin-clarithromycin and colistinclarithromycin-carbapenems.

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