scholarly journals Synthesis, Characterization, and Antimicrobial Activity of a Novel Trisazo Dye from 3-Amino-4H-thieno[3,4-c][1]benzopyran-4-one

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Joseph Tsemeugne ◽  
Emmanuel Sopbué Fondjo ◽  
Jean-de-Dieu Tamokou ◽  
Taoufik Rohand ◽  
Arnaud Djintchui Ngongang ◽  
...  
Keyword(s):  
Spectroscopic Data ◽  
2D Nmr ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Human Pathogens ◽  
Bacterial Strains ◽  
Antibacterial And Antifungal Activities ◽  
Diazonium Ion ◽  
Antibacterial And Antifungal ◽  
Susceptibility Assay

A new trisazo dye has been synthesized by coupling the diazonium ion of 3-amino-4H thieno[3,4-c][1]benzopyran-4-one with 2-tert-butyl-4-methoxyphenol. The newly prepared trisazo dye was characterized by its physical, elemental, and spectroscopic data. 2D-NMR (COSY, HSQC, and HMBC) techniques were used to secure the structural assignments. The new trisazo dye (compound 7) along with precursors 3, 4, and 6 was screened by microdilution susceptibility assay for antibacterial and antifungal activities towards eight bacterial strains and three yeasts selected on the basis of their relevance as human pathogens. The results showed that compound 7 (MIC = 2–128 μg/mL) was the most active as compared with its precursors. The most resistant microorganisms were V. cholerae NB2 and V. cholerae SG24, whereas the most sensitive microorganism was C. neoformans. The overall results of this study indicated that compound 7 had the greatest potential value against both yeasts and multidrug-resistant bacteria, so further investigation is warranted.

scholarly journals In VitroPhytochemical, Antibacterial, and Antifungal Activities of Leaf, Stem, and Root Extracts ofAdiantum capillus veneris

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Muhammad Saqib Ishaq ◽  
Muhammad Medrar Hussain ◽  
Muhammad Siddique Afridi ◽  
Ghadir Ali ◽  
Mahrukh Khattak ◽  
...  
Keyword(s):  
Multidrug Resistant ◽  
Antimicrobial Activities ◽  
Phytochemical Analysis ◽  
Bacterial Strains ◽  
Antifungal Activities ◽  
Fungal Strains ◽  
Antibacterial And Antifungal Activities ◽  
Adiantum Capillus Veneris ◽  
Ethanol Extracts ◽  
Antibacterial And Antifungal

Adiantum capillus venerisis a medicinally essential plant used for the treatment of diverse infectious diseases. The study of phytochemical and antimicrobial activities of the plant extracts against multidrug-resistant (MDR) bacteria and medically important fungi is of immense significance. Extracts from the leaves, stems, and roots ofAdiantum capillus veneriswere extracted with water, methanol, ethanol, ethyl acetate, and hexane and screened for their antimicrobial activity against ten MDR bacterial strains and five fungal strains isolated from clinical and water samples. Ash, moisture, and extractive values were determined according to standard protocols. FTIR (Fourier transform infrared Spectroscopy) studies were performed on different phytochemicals isolated from the extracts ofAdiantum capillus Veneris. Phytochemical analysis showed the presence of flavonoids, alkaloids, tannins, saponins, cardiac glycosides, terpenoids, steroids, and reducing sugars. Water, methanol, and ethanol extracts of leaves, stems, and roots showed significant antibacterial and antifungal activities against most of the MDR bacterial and fungal strains. This study concluded that extracts ofAdiantum capillus venerishave valuable phytochemicals and significant activities against most of the MDR bacterial strains and medically important fungal strains.

scholarly journals Antibacterial and Antifungal Property of Actinomycetes Isolates from Soil and Water of Nepal

2018 ◽  
Vol 16 (2) ◽  
pp. 136-139 ◽  
Author(s):  
Binod Lekhak ◽  
Anjana Singh ◽  
Dwij Raj Bhatta
Keyword(s):  
Pathogenic Bacteria ◽  
Antimicrobial Property ◽  
Salmonella Typhi ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Human Pathogens ◽  
Antifungal Property ◽  
Bioactive Metabolite ◽  
Antibacterial And Antifungal ◽  
Soil And Water

Background: Human pathogens are rapidly acquiring resistance to antibiotics leading to treatment failure. We carried out this study to isolate and screen actinomycetes strains that have potential to kill bacterial and fungal pathogens.Methods: In this descriptive study 288 soil and water samples were processed by standard microbiological techniques at Central Department of Microbiology, Tribhuvan University from 2013 to 2015. Screened actinomycetes were cultivated for bioactive metabolite production and minimum inhibitory concentration (MIC) of metabolites were determined against bacterial pathogens including multidrug resistant bacteria and fungi.Results: One hundred twenty isolates having antimicrobial property were screened. Out of them, four most potent strains, Nocardiopsis prasina, Streptomyces violarus, Streptomyces krainskii and Streptomyces tsusimaensis were identified all having both antibacterial and anti-fungal property.Highest zone of inhibition (ZOI)was given by N. prasina against Candida albicans(41.33 ±1.15mm) and among bacteria, maximum ZOI was against Acinetobacter baumannii(31.33±3.05mm). MIC value of metabolite of N.prasina was 0.125mg/ml for E.coli and C. albicans. It was 2.5 mg/ml each for methicillin resistant Staphylococcus aureus (MRSA), A. baumannii and Salmonella Typhi and 0.625 mg/ml for Bacillus Subtilis.Conclusions: Bioactive metabolite producing actinomycetes were recovered from soil and tested against human pathogenic bacteria and fungiand found to have antibacterial and antifungal property.

scholarly journals Activity of the Novel Peptide Arminin against Multiresistant Human Pathogens Shows the Considerable Potential of Phylogenetically Ancient Organisms as Drug Sources

2009 ◽  
Vol 53 (12) ◽  
pp. 5245-5250 ◽  
Author(s):  
René Augustin ◽  
Friederike Anton-Erxleben ◽  
Stephanie Jungnickel ◽  
Georg Hemmrich ◽  
Björn Spudy ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Multidrug Resistant ◽  
Proteolytic Processing ◽  
Erythrocyte Membranes ◽  
Resistant Bacteria ◽  
Minimal Bactericidal Concentration ◽  
Human Pathogens ◽  
Bacterial Strains ◽  
Multiresistant Bacteria ◽  
High Level

ABSTRACT The emergence of multidrug-resistant bacteria highlights the need for new antibacterial agents. Arminin 1a is a novel antimicrobial peptide discovered during investigations of the epithelial defense of the ancient metazoan Hydra. Following proteolytic processing, the 31-amino-acid-long positively charged C-terminal part of arminin 1a exhibits potent and broad-spectrum activity against bacteria, including multiresistant human pathogenic strains, such as methicillin-resistant Staphylococcus aureus (MRSA) strains (minimal bactericidal concentration, 0.4 μM to 0.8 μM). Ultrastructural observations indicate that bacteria are killed by disruption of the bacterial cell wall. Remarkably, the antibacterial activity of arminin 1a is not affected under the physiological salt conditions of human blood. In addition, arminin 1a is a selective antibacterial agent that does not affect human erythrocyte membranes. Arminin 1a shows no sequence homology to any known antimicrobial peptide. Because of its high level of activity against multiresistant bacterial strains pathogenic for humans, the peptide arminin 1a is a promising template for a new class of antibiotics. Our data suggest that ancient metazoan organisms such as Hydra hold promise for the detection of novel antimicrobial molecules and the treatment of infections caused by multiresistant bacteria.

scholarly journals Phytochemical investigation and in vitro antimicrobial activity of Richardia scabra

2016 ◽  
Vol 11 (2) ◽  
pp. 248 ◽  
Author(s):  
Kathirvel Poonkodi ◽  
Subban Ravi
Keyword(s):  
Antimicrobial Activity ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Weed Species ◽  
Antibacterial And Antifungal Activities ◽  
Agar Plug ◽  
Phytochemical Investigation ◽  
Antibacterial And Antifungal ◽  
Simple Sugar

<p class="Abstract">The present study was aimed to evaluate the phytochemical screening and antimicrobial activity of the petroleum ether and methanol extracts from the mature leaves of <em>Richardia scabra</em> from India. Disc diffusion method was used to determine the zone inhibition of the tested samples for antibacterial and agar plug method was used to determine the antifungal activity, while the microtube-dilution technique was used to determine the minimum inhibitory concentration. Both extracts showed significant antibacterial and antifungal activities when tested against 10 bacterial and four fungal strains. The minimum inhibitory concentrations of the methanol extract of<em> R. scabra</em> ranged between 12.5–100 μg/mL for bacterial strains. Alkaloids, steroids, flavonoids, fatty acids, terpenoids and simple sugar were detected as phytoconstituents of extracts. To the best of our knowledge, this is the first report against antimicrobial activity of common weed species <em>R. scabra</em> found in India.</p><p> </p>

scholarly journals Advances in Antarctic Research for Antimicrobial Discovery: A Comprehensive Narrative Review of Bacteria from Antarctic Environments as Potential Sources of Novel Antibiotic Compounds Against Human Pathogens and Microorganisms of Industrial Importance

Antibiotics ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 90 ◽  
Author(s):  
Kattia Núñez-Montero ◽  
Leticia Barrientos
Keyword(s):  
Public Health Problem ◽  
Narrative Review ◽  
Bioactive Molecules ◽  
Resistant Bacteria ◽  
Natural Environments ◽  
Antimicrobial Compounds ◽  
Human Pathogens ◽  
Bacterial Strains ◽  
Antarctic Bacteria ◽  
Recent Emergence

The recent emergence of antibiotic-resistant bacteria has become a critical public health problem. It is also a concern for industries, since multidrug-resistant microorganisms affect the production of many agricultural and food products of economic importance. Therefore, discovering new antibiotics is crucial for controlling pathogens in both clinical and industrial spheres. Most antibiotics have resulted from bioprospecting in natural environments. Today, however, the chances of making novel discoveries of bioactive molecules from various well-known sources have dramatically diminished. Consequently, unexplored and unique environments have become more likely avenues for discovering novel antimicrobial metabolites from bacteria. Due to their extreme polar environment, Antarctic bacteria in particular have been reported as a potential source for new antimicrobial compounds. We conducted a narrative review of the literature about findings relating to the production of antimicrobial compounds by Antarctic bacteria, showing how bacterial adaptation to extreme Antarctic conditions confers the ability to produce these compounds. We highlighted the diversity of antibiotic-producing Antarctic microorganisms, including the phyla Proteobacteria, Actinobacteria, Cyanobacteria, Firmicutes, and Bacteroidetes, which has led to the identification of new antibiotic molecules and supports the belief that research on Antarctic bacterial strains has important potential for biotechnology applications, while providing a better understanding of polar ecosystems.

scholarly journals Production of a New Thiopeptide Antibiotic, TP-1161, by a Marine Nocardiopsis Species

2010 ◽  
Vol 76 (15) ◽  
pp. 4969-4976 ◽  
Author(s):  
Kerstin Engelhardt ◽  
Kristin F. Degnes ◽  
Michael Kemmler ◽  
Harald Bredholt ◽  
Espen Fj�rvik ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Molecular Taxonomy ◽  
Multidrug Resistant ◽  
Peptide Antibiotic ◽  
Indicator Organisms ◽  
Bacterial Strains ◽  
Pcr Screening ◽  
Vancomycin Resistant ◽  
Antibacterial And Antifungal

ABSTRACT Twenty-seven marine sediment- and sponge-derived actinomycetes with a preference for or dependence on seawater for growth were classified at the genus level using molecular taxonomy. Their potential to produce bioactive secondary metabolites was analyzed by PCR screening for genes involved in polyketide and nonribosomal peptide antibiotic synthesis. Using microwell cultures, conditions for the production of antibacterial and antifungal compounds were identified for 15 of the 27 isolates subjected to this screening. Nine of the 15 active extracts were also active against multiresistant Gram-positive bacterial and/or fungal indicator organisms, including vancomycin-resistant Enterococcus faecium and multidrug-resistant Candida albicans. Activity-guided fractionation of fermentation extracts of isolate TFS65-07, showing strong antibacterial activity and classified as a Nocardiopsis species, allowed the identification and purification of the active compound. Structure elucidation revealed this compound to be a new thiopeptide antibiotic with a rare aminoacetone moiety. The in vitro antibacterial activity of this thiopeptide, designated TP-1161, against a panel of bacterial strains was determined.

scholarly journals Multidrug Resistant and Extensively Drug Resistant Bacteria: A Study

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Silpi Basak ◽  
Priyanka Singh ◽  
Monali Rajurkar
Keyword(s):  
Antimicrobial Resistance ◽  
Antibiotic Susceptibility ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Close Monitoring ◽  
Care Hospital ◽  
Drug Resistant ◽  
Bacterial Isolates ◽  
Bacterial Strains ◽  
Extensively Drug Resistant

Background and Objective. Antimicrobial resistance is now a major challenge to clinicians for treating patients. Hence, this short term study was undertaken to detect the incidence of multidrug-resistant (MDR), extensively drug-resistant (XDR), and pandrug-resistant (PDR) bacterial isolates in a tertiary care hospital.Material and Methods. The clinical samples were cultured and bacterial strains were identified in the department of microbiology. The antibiotic susceptibility profile of different bacterial isolates was studied to detect MDR, XDR, and PDR bacteria.Results. The antibiotic susceptibility profile of 1060 bacterial strains was studied. 393 (37.1%) bacterial strains were MDR, 146 (13.8%) strains were XDR, and no PDR was isolated. All (100%) Gram negative bacterial strains were sensitive to colistin whereas all (100%) Gram positive bacterial strains were sensitive to vancomycin.Conclusion. Close monitoring of MDR, XDR, or even PDR must be done by all clinical microbiology laboratories to implement effective measures to reduce the menace of antimicrobial resistance.

scholarly journals Susceptibility Assessment of Multidrug Resistant Bacteria to Natural Products

Dose-Response ◽  
2020 ◽  
Vol 18 (3) ◽  
pp. 155932582093618
Author(s):  
Essam Hassan Mohamed ◽  
Youssef Saeed Alghamdi ◽  
Salama Mostafa Abdel-Hafez ◽  
Mohamed Mohamed Soliman ◽  
Saad H. Alotaibi ◽  
...  
Keyword(s):  
Inhibitory Concentration ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Syzygium Aromaticum ◽  
Bacterial Strains ◽  
Multidrug Resistant Bacteria ◽  
Scanning Electron Microscope Analysis ◽  
Electron Microscope Analysis ◽  
Holothuria Atra ◽  
Scanning Electron

Objective: The aim of this study was to examine the effect of some natural compounds against multidrug-resistant bacteria. Methods: Forty-three bacterial strains were collected. Disc diffusion and minimum inhibitory concentration (MIC) tests were carried out for natural compounds including quercetin, Acacia nilotica, Syzygium aromaticum, and Holothuria atra. Scanning electron microscope analysis and bacterial DNA apoptosis assays were performed. Results: Staphylococcus aureus strains were resistant to imipenim, ampicillin, and penicillin. Most Escherichia coli strains were resistant to amoxicillin, clavulanat, and ampicillin. Finally, tigecycline was effective with Klebsiella pneumoniae and was resistant to all antibiotics. Only S aromaticum had an antibacterial effect on K pneumoniae. Most S aureus strains were sensitive to S aromaticum, A nilotica, and quercetin. All examined natural extracts had no effect on E coli. Holothuria atra had no effect on any of the strains tested. Minimum inhibitory concentration and minimum bactericidal concentration values for examined plants against S aureus were 6.25 to 12, 1.6 to 3.2, and 9.12 to 18.24 mg/mL, respectively. Syzygium aromaticum was active against K pneumoniae with an MIC of 12.5 mg/mL. Scanning electron microscope analysis performed after 24 and 48 hours of incubation showed bacterial strains with distorted shapes and severe cell wall damage. Syzygium aromaticum, quercetin, and A nilotica showed clear fragmentations of S aureus DNA. Conclusions: Current findings confirmed the beneficial effect of using natural products such as clove (S aromaticum), quercetin, and A nilotica as a promising therapy to overcome multidrug resistant bacteria.

scholarly journals Emergence of plasmid-mediated mcr genes from Gram-negative bacteria at the human-animal interface

Gut Pathogens ◽  
2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Humera Javed ◽  
Sidrah Saleem ◽  
Aizza Zafar ◽  
Aamir Ghafoor ◽  
Ahmad Bin Shahzad ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Multidrug Resistant ◽  
Detection Methods ◽  
Human Pathogens ◽  
Bacterial Strains ◽  
Gram Negative ◽  
Polymerase Chain ◽  
Animal Isolates ◽  
Animal Strains ◽  
Microbiological Procedures

Abstract Background The global emergence of plasmid-mediated colistin resistance (Col-R) conferred by mcr genes in gram-negative rods (GNRs) has jeopardized the last treatment option for multidrug-resistant bacterial infections in humans. This study aimed to assess the emergence of mcr gene-mediated Col-R in GNRs isolated from humans and animals in Pakistan. Methods Animal and clinical specimens collected from various sources were prospectively analysed using standard microbiological procedures. Pathogens were identified using the API 20E and API 20NE systems (bioMerieux). Minimum inhibitory concentration (MIC) against colistin was determined using the MIC detection methods, and multiplex polymerase chain reaction (PCR) was used to amplify the mcr-1 to mcr-5 genes. Results We isolated 126 (88.1%) animal and 17 (11.9%) human Col-R phenotypes, among which there was a significant association (P < 0.01) of Escherichia coli and Proteus mirabilis with animals and of Acinetobacter baumannii with humans. Animal strains exhibited statistically significant (P < 0.05) resistance to co-trimoxazole, chloramphenicol, and moxifloxacin, and the human pathogens exhibited statistically significant (P < 0.05) antibiotic resistance to cephalosporins, carbapenems, and piperacillin-tazobactam. For Col-R strains, MIC50 values were > 6 µg/mL and > 12 µg/mL for human and animal isolates, respectively. mcr genes were detected in 110 (76.9%) bacterial strains, of which 108 (98.2%) were mcr-1 and 2 (1.8%) were mcr-2. Conclusions The detection of a considerable number of mcr-1 and mcr-2 genes in animals is worrisome, as they are now being detected in clinical pathogens. The acquisition of mcr genes by colistin-susceptible bacteria could leave us in a post-antibiotic era.

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