scholarly journals Antibacterial Activity of Human Neutrophil Defensin HNP-1 Analogs without Cysteines

2005 ◽  
Vol 49 (11) ◽  
pp. 4561-4566 ◽  
Author(s):  
Jobin Varkey ◽  
Ramakrishnan Nagaraj
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Human Neutrophil ◽  
Therapeutic Agents ◽  
Proton Motive Force ◽  
Motive Force ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Carbonyl Cyanide

ABSTRACT The antibacterial activity of human neutrophil defensin HNP-1 analogs without cysteines has been investigated. A peptide corresponding to the HNP-1 sequence without the six cysteines (HNP-1ΔC) exhibited antibacterial activity toward gram-negative and gram-positive bacteria. Truncated analogs wherein the nine N-terminal residues of HNP-1 and the remaining three cysteines were deleted (HNP-1ΔC18) or the G was replaced with A (HNP-1ΔC18A) also exhibited antibacterial activity. Substantial activity was observed for HNP-1ΔC and HNP-1ΔC18 in the presence of 100 mM NaCl, except in the case of Pseudomonas aeruginosa. The linear peptides were active in the presence of carbonyl cyanide m-chlorophenylhydrazone (CCCP), indicating that proton motive force was not essential for killing of bacteria by the peptides. In fact, in the presence of CCCP, the peptides were active against P. aeruginosa even in the presence of 100 mM NaCl. The antibacterial activity of HNP-1ΔC, but not that of the shorter, 18-residue peptides, was attenuated in the presence of serum. The generation of defensins without cysteines would be easier than that of disulfide-linked defensins. Hence, linear defensins could have potential as therapeutic agents.

Antibacterial activity of magnesium oxide nanoparticles prepared by Calcination method

2019 ◽  
Vol 10 (03) ◽  
Author(s):  
Elaf Ayad Kadhem ◽  
Miaad Hamzah Zghair ◽  
Sarah , Hussam H. Tizkam, Shoeb Alahmad Salih Mahdi ◽  
Hussam H. Tizkam ◽  
Shoeb Alahmad
Keyword(s):  
Antibacterial Activity ◽  
Magnesium Oxide ◽  
Diffusion Method ◽  
Oxide Nanoparticles ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Magnesium Oxide Nanoparticles ◽  
Agar Disc

magnesium oxide nanoparticles (MgO NPs) were prepared by simple wet chemical method using different calcination temperatures. The prepared NPs were characterized by Electrostatic Discharge (ESD), Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). It demonstrates sharp intensive peak with the increase of crystallinty and increase of the size with varying morphologies with respect to increase of calcination temperature. Antibacterial studies were done on gram negative bacteria (E.coli) and gram positive bacteria (S.aureus) by agar disc diffusion method. The zones of inhibitions were found larger for gram positive bacteria than gram negative bacteria, this mean, antibacterial MgO NPs activity more active on gram positive bacteria than gram negative bacteria because of the structural differences. It was found that antibacterial activity of MgO NPs was found it has directly proportional with their concentration.

scholarly journals Antibacterial Activity of Macrocyclic Complexes of Cu(II), Ni(II) and VO(II) Derived fromo-Aminobenzaldehyde

2012 ◽  
Vol 9 (1) ◽  
pp. 481-486
Author(s):  
K. Anuradha ◽  
R. Rajavel
Keyword(s):  
Antibacterial Activity ◽  
Elemental Analysis ◽  
Molar Conductance ◽  
Macrocyclic Complexes ◽  
Spectral Studies ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Novel Cu(II),Ni(II) and VO(II) complexes are synthesized with N1,N4-bis(2-aminobenzylidene)benzene-1,4-diamine (L). Complexes were characterized by elemental analysis, molar conductance, IR, UV and EPR. Spectral studies reveals a square planner geomentry for Cu(II), Ni(II) complexes and square pyramidal for VO(II) complex. The ligand and its complexes were also evaluated against the growth of gram positive bacteria and gram negative bacteria.

scholarly journals Chemical Composition and Antibacterial Activity of the Essential Oil of Espeletia nana

2012 ◽  
Vol 7 (5) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Alexis Peña ◽  
Luis Rojas ◽  
Rosa Aparicio ◽  
Libia Alarcón ◽  
José Gregorio Baptista ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative ◽  
Gram Positive Bacteria

The essential oil of the leaves of Espeletia nana Cuatrec, obtained by hydrodistillation, was analyzed by GC-MS, which allowed the identification of 24 components, which made up 99.9% of the oil. The most abundant compounds were α-pinene (38.1%), β-pinene (17.2%), myrcene (15.0%), spathulenol (4.2%), bicyclogermacrene (4.0%), α-zingiberene (4.0%), and γhimachalene (3.7%). Antibacterial activity was tested against Gram-positive and Gram-negative bacteria using the agar disk diffusion method. Activity was observed only against Gram-positive bacteria. MIC values were determined for Staphylococcus aureus ATCC 25923(200 μg/mL) and Enterococcus faecalis ATCC 29212 (600 μg/mL).

scholarly journals Water-dispersible glycosylated poly(2,5′-thienylene)porphyrin-based nanoparticles for antibacterial photodynamic therapy

2019 ◽  
Vol 18 (5) ◽  
pp. 1147-1155 ◽  
Author(s):  
Rehan Khan ◽  
Melis Özkan ◽  
Aisan Khaligh ◽  
Dönüs Tuncel
Keyword(s):  
Antibacterial Activity ◽  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Water Dispersible ◽  
Gram Positive Bacteria ◽  
High Yields

Water-dispersible glycosylated poly(2,5′-thienylene)porphyrin-based nanoparticles have the ability to generate singlet oxygen in high yields and exhibit light-triggered antibacterial activity against Gram negative bacteria, E. coli as well as Gram positive bacteria, B. subtilis.

scholarly journals Synthesis and Antibacterial Activity of Chalcones and Pyrimidine-2-ones

2005 ◽  
Vol 2 (2) ◽  
pp. 109-112
Author(s):  
A. K. Parekh ◽  
K. K. Desai
Keyword(s):  
Antibacterial Activity ◽  
Spectral Data ◽  
Elemental Analysis ◽  
Aromatic Aldehydes ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
H Nmr

Some new chalcones have been prepared by Claisen-schmidt condensation of ketone and different aromatic aldehydes. These chalcones on condensation with urea in presence of acid gave Pyrimidine-2-ones. The synthesized compounds have been characterized by elemental analysis, IR and1H NMR spectral data. They have been screened for their antibacterial activity against Gram positive bacteria B. subtillis & S. aureus and Gram negative bacteria E. coli & S. typhi.

scholarly journals Antibacterial Activities of Xanthium Strumarium L.

2018 ◽  
Vol 29 ◽  
pp. 70-77 ◽  
Author(s):  
Anjana Devkota ◽  
Ritu Kumari Das
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Antibacterial Activities ◽  
Diffusion Method ◽  
Xanthium Strumarium ◽  
Distilled Water ◽  
Leaf Extracts ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Antibacterial activities of Xanthium strumarium L. (Asteraceae) was carried out in laboratory. Distilled water and methanol extracts of the leaves of plant was prepared. The antibacterial activity was studied against six pathogenic bacteria, three gram negative: Klebsiella pneumoniae (ATCC 15380), Proteus mirabilis (ATCC 49132), Escherichia coli (ATCC 25922) and three gram positive: Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 25932) at different concentrations (50 mg/ml, 100 mg/ml, 150 mg/ml, 200 mg/ ml, 250 mg/ml) of leaf extracts of X. strumurium. The phytochemical screening depicted the presence of terpenoids, saponins, flavonoids, tannins and alkaloids. The antibacterial activity of extracts was determined by disc diffusion method and zone of inhibition (ZOI) was measured. Gram negative bacteria was found more resistant than gram positive bacteria. The most susceptible bacterium was S. aureus while the most resistant bacterium was E. coli. Methanolic extract was found more effective than distilled water. These findings suggest that extracts obtained from leaves of X. strumurium possess biobactericidal potential, which can suitably be exploited for making antibacterial drugs.J. Nat. Hist. Mus. Vol. 29, 2015, Page: 70-77

scholarly journals Bacterial Profile and Antibiogram of Hospital-Acquired Pneumonia and Ventilator-Associated Pneumonia Patients in ICU of Raden Mattaher Hospital Jambi

2020 ◽  
Vol 26 (3) ◽  
Author(s):  
Sotianingsih Sotianingsih ◽  
Samsirun H. ◽  
Lipinwati Lipinwati
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Culture Media ◽  
Sensitivity Test ◽  
Sputum Culture ◽  
Klebsiella Pneumonia ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Acinetobacter Baumanii ◽  
Gram Negative ◽  
Gram Positive Bacteria

Pneumonia is defined as an inflammation of the lungs caused by microorganisms (bacteria, viruses, fungi, parasites). This research aimed to determine the pneumonia-causing bacteria along with the sensitivity and the antibiotic resistance test. This research was a descriptive study with samples of ICU pneumonia patients at Raden Mattaher Regional Hospital during the study period. All samples were consecutively selected. Samples for blood culture were incubated in the BactAlert device, whereas the sensitivity test was then performed using Vitex instruments. Sputum was previously enriched with BHI media and then cultured on culture media, and sensitivity test with the Vitex instruments was carried out. Of the 354 ICU patients during the study period, 30 patients (11.8%) had pneumonia, but only 19 patients could undergo sputum culture. Five of 19 patients were infected with Gram-positive bacteria, and 14 patients were infected with Gram-negative bacteria. The most commonly found bacteria were Klebsiella pneumonia (36.84%), followed by Acinetobacter baumanii (21.05%) and Pseudomonas aeruginosa (10.53%). Gram-negative bacteria obtained from sputum culture in this study were resistant to almost all antibiotic groups, especially penicillin, cephalosporin, quinolone, and tetracycline groups. Gram-positive bacteria obtained from sputum culture in this study were resistant to the penicillin antibiotic. The most commonly found bacteria were Klebsiella pneumonia (36.84%), followed by Acinetobacter baumanii (21.05%) and Pseudomonas aeruginosa (10.53%). The bacteria cultured from the sputum showed multidrug resistance mainly to the penicillin and cephalosporin antibiotic. This research data can be used to consider the treatment of pneumonia patients to decide more appropriate therapy.

scholarly journals Identification of the microflora from the oral cavity of exotic snakes kepth as pets

2020 ◽  
Vol 12 (2) ◽  
pp. 56-63
Author(s):  
Marko Naumovski ◽  
Ivamaria Jovanovska ◽  
Kakja Popovska ◽  
Vesna Velikj Stefanovska ◽  
Gordana Mirchevska
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Oral Cavity ◽  
Gram Negative Bacteria ◽  
Proteus Vulgaris ◽  
Gram Positive ◽  
Providencia Rettgeri ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Venomous Snakes ◽  
The Republic

In recent years, snakes have become suitable pets for people with little spare time. By buying these animals people ignore the fact that they carry many microorganisms that are pathogenic for humans. The idea of ​​this study was to identify the microorganisms from the oral cavity of exotic snakes kept as pets in the Republic of North Macedonia, which can help in the treatment of bite infections if they occur. The study comprised 30 snakes of 9 species, from 3 families of non-venomous snakes: Pythonidae, Boidae and Colubridae. Snakes are part of the 5 largest collections of exotic snakes in the Republic of North Macedonia. Only one swab from the oral cavity was taken from each snake. The brushes were cultured and microscopically analyzed at the Institute of Microbiology and Parasitology at the Faculty of Medicine in Skopje. From 59 isolated microorganisms from the oral cavity of 30 exotic snakes, 37.3% were Gram-positive bacteria, 61.01% were Gram-negative bacteria and 1.69% were fungi. Of the total number of microorganisms, Pseudomonas aeruginosa was predominant with 27.11%, Providencia rettgeri / Proteus vulgaris with 18.64% and KONS / Micrococcus luteus with 16.94%. Pseudomonas aeruginosa was present in all three snake families, with 62.5% of the snake in the fam. Pythonidae; 50% in the fam. Boidae and 50% in the fam. Colubridae. The isolate Providencia rettgeri / Proteus vulgaris was most frequently found in the fam. Colubridae with 71.43%, followed by fam. Pythonidae with 12.5%, but was not isolated in any specimen of the fam. Boidae. The microbiome of the non-venomous snakes is composed of Gram-positive bacteria in healthy snakes, but also in snakes kept in inadequate hygienic conditions. Gram-negative bacteria were predominant, of which the most significant was the presence of multiple drug resistance Pseudomonas aeruginosa. Snakes as pets require proper knowledge of terms and conditions.

scholarly journals Antibacterial activity of Beta vulgaris L. pomace extract

2011 ◽  
pp. 263-269 ◽  
Author(s):  
Aleksandra Velicanski ◽  
Dragoljub Cvetkovic ◽  
Sinisa Markov ◽  
Jelena Vulic ◽  
Sonja Djilas
Keyword(s):  
Antibacterial Activity ◽  
Beta Vulgaris ◽  
Staphylococcus Epidermidis ◽  
Control Sample ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Natural Isolates

Antibacterial activity of Beta vulgaris L. (beetroot) pomace extract (concentration 100 mg/ml) was tested against five Gram positive and seven Gram negative bacterial strains (reference cultures and natural isolates). Disc diffusion method with 15 ?l of extract and agar-well diffusion method with 50 and 100 ?l were used. Antibiotic (cefotaxime/clavulanic acid) was used as a control sample. The tested extract showed the highest activity against Staphylococcus aureus and Bacillus cereus, where clear zones (without growth) appeared. There was no any activity against other tested Gram-positive bacteria, except for Staphylococcus epidermidis, with a small zone of reduced growth. Growth of all tested Gram-negative bacteria was inhibited usually with 100 ?l of extract. The most susceptible were Citrobacter freundii and Salmonella typhymurium. The tested antibiotic gave clear, usually large zones for all tested strains except for Staphylococcus cohni spp. cohni, where only a zone of reduced growth appeared.

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