Effect of Synthesized Ag Nanoparticles by Using the Different Amounts of Polyvinylpyrrolidone for Ag-Natural Rubber Hybrid Sheets and their Antibacterial Properties

2017 ◽  
Vol 751 ◽  
pp. 270-276 ◽  
Author(s):  
Warot Prasanseang ◽  
Chaval Sriwong ◽  
Kittisak Choojun
Keyword(s):  
Natural Rubber ◽  
Low Cost ◽  
Antibacterial Properties ◽  
Rubber Matrix ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Zones Of Inhibition ◽  
Ft Ir ◽  
The Mean

Ag-natural rubber (Ag-NR) hybrid sheets were successfully prepared with a very simple and low cost method. In this method, silver nanoparticles (AgNPs) were firstly synthesized by a rapid and green microwave-assisted using polyvinylpyrroridone (PVP) media. The effect of PVP weight ratios towards the size of AgNPs was also investigated. Then, Ag-NR hybrid sheet samples were prepared by latex mixing-casting method using concentrated natural rubber (NR) latex with the synthesized AgNPs colloids. The characteristic absorption, particles sizes and shapes of the obtained AgNPs were examined through UV-vis, TEM and SAED. Also, the prepared Ag-NR sheet samples were characterized using XRD, FT-IR, SEM and EDS techniques. It was found that the particles sizes of all the synthesized AgNPs had spherical-like shape, and the mean sizes were increased from 29.7 to 90.4 nm upon increasing PVP contents. EDS results showed the AgNPs were well-dispersed and impregnated into the rubber matrix. Moreover, the antibacterial properties of the prepared Ag-NR sheets were tested by agar disk-diffusion method with Gram-positive and Gram-negative bacteria as Staphylococcus aureus(S. aureus) and Escherichia coli(E. coli), respectively. The results showed that the hybrid sheets exhibited excellent antibacterial properties against these bacteria, in which the zones of inhibition were also dependent on the synthesized AgNPs by utilizing the different amounts of PVP.

scholarly journals In vitro Synergistic Antimicrobial Activity of Romanian Propolis and Antibiotics against Escherichia coli Isolated from Bovine Mastitis

2015 ◽  
Vol 43 (2) ◽  
pp. 327-334 ◽  
Author(s):  
Mihaela NICULAE ◽  
Laura STAN ◽  
Emoke PALL ◽  
Anamaria Ioana PAȘTIU ◽  
Iulia Maria BALACI ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Chemical Composition ◽  
Bovine Mastitis ◽  
Antibacterial Properties ◽  
Disk Diffusion ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Ethanolic Extracts

The study was aimed to characterize the chemical composition and the antimicrobial activity of Romanian propolis ethanolic extracts (EEP) against antibiotic-sensitive and antibiotic-resistant E. coli strains isolated from bovine mastitis. The preliminary antimicrobial screening was performed by a disk diffusion method, followed by determination of minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) based on broth microdilution assay; further, the synergistic action of propolis with antimicrobial drugs was assessed by a disk diffusion method on agar containing subinhibitory concentrations of propolis. For the chemical characterisation of EEP, the flavonoids (flavones/flavonols, flavanones/dihydroflavonols) and total phenolics were evaluated by spectrophotometric methods. The phenolic compounds of these extracts were also determined using HPLC. The results indicated for Romanian propolis ethanolic extracts the typical poplar composition profile with flavonoids and phenolic acids as main biological active compounds, with chromatographic analysis data confirmed also spectrophotometrically. In addition, positively correlated with the chemical composition, a strong antimicrobial efficacy was exhibited towards E. coli strains, along with interesting synergistic interaction with antibiotics that can be further investigated to obtain propolis-based formulation with antibacterial properties. Subsequent in vitro and in vivo studies evaluating the safety and efficacy are intended to consider propolis in veterinary therapeutic protocols.

scholarly journals Impact of decalcification on antibacterial properties of eggshell against selected poultry pathogens

2021 ◽  
Vol 22 (2) ◽  
pp. 204-210
Author(s):  
T.V. Balogu ◽  
B.C. Chukwueze ◽  
T.P. Okonkwo
Keyword(s):  
Antibacterial Effect ◽  
Antibacterial Properties ◽  
Fine Powder ◽  
Inhibitory Effect ◽  
Diffusion Method ◽  
Mean Values ◽  
Significance Level ◽  
E Coli ◽  
Zone Diameter ◽  
The Mean

Background: Eggshell which is primarily composed of more than 98% calcium carbonate crystal, serves as the physical protective and active barrier structure of egg content. Recently, antimicrobial properties of eggshell are fast becoming center of interest among stakeholders of poultry industry. However, few studies have focused on the rigidity factor of calcium components of eggshell as antimicrobial agent. Thus, this study was designed to determine the effect of decalcification on the ability of eggshell to inhibit common poultry and egg bacterial pathogens.Methods: Raw eggshell denoted as calcified eggshell (CES) and decalcified eggshell (DES) were extracted and made into fine powder. Standard protocol was used for preparations of CES and DES at concentrations of 10, 5, 2.5 and 1.25 mg/ml, and their antibacterial assays on selected bacterial pathogens (Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Salmonella Typhi) were performed by agar diffusion method. Gentamicin 80mg solution (CC1) and distilled water (CC2) served as controls. Data were analysed with SPSS version 20.0 and presented as mean±SD for descriptive statistics. Friedman's two-way test ANOVA was used to compare the differences in mean values between CES, DES, CC1 and CC2 at significance level of p<0.05.Results: The mean zone diameter of inhibition produced by DES (range 13–28mm) for the isolates was significantly higher (p<0.05) than that produced by CES (range 10-21mm). However, the mean zone diameter of inhibition produced by CC1 (gentamicin) (range 16-40mm) was higher than that produced by DES or CES (p<0.05). The concentrations of DES and CES have no significant antibacterial effect on B. subtilis and K. pneumoniae (p>0.05), but had inverse effect on P. aeruginosa. Overall, DES had a better inhibitory effect than CES against B. subtilis, K. pneumoniae and P. aeruginosa, but notably, neither DES nor CES had inhibitory effect on E. coli and S. Typhi.Conclusion: Poor antibacterial effect of CES may be attributed to the calcium-protein interactions within bacterial cell membrane, which hinders absorption or mobility mechanism of the antibacterial factor of the eggshell, but decalcification had significant impact on the antibacterial profile of the eggshell for some bacterial isolates. However, S. Typhi and E. coli were totally resistant to both DES and CES. Breed of eggs with minimal calcified eggshell to withstand transportation fragility, may enhance antibacterial index and shelf-life of table eggs. Keywords: Decalcification; Antibacterial; Eggshell; Poultry; Pathogens

scholarly journals Comparative In vitro Antibacterial Properties of Methanol Extracts and Fractions of Myristica fragrans Seed and Thymus vulgaris Leaf

2021 ◽  
pp. 47-58
Author(s):  
Romanus A. Umoh ◽  
Affiong C. Essien ◽  
Imoh I. Johnny ◽  
Nsima A. Andy ◽  
Anwanabasi E. Udoh ◽  
...  
Keyword(s):  
Methanol Extract ◽  
Antibacterial Properties ◽  
Absolute Methanol ◽  
Diffusion Method ◽  
Thymus Vulgaris ◽  
Gram Positive ◽  
E Coli ◽  
Methanol Extracts ◽  
Myristica Fragrans ◽  
Zones Of Inhibition

The aim of this work was to compare the antibacterial properties of methanol extracts and fractions of Myristica fragrans seed and Thymus vulgaris leaf on the gram positive and negative bacteria.  The Myristica fragrans seeds were crushed, defatted and air-dried. The defatted seed and leaf powders were separately macerated in absolute methanol for 72 hours. The methanol extracts and fractions were reconstituted at different concentrations of 100mg/mL, 80mg/mL, 60mg/mL, 40mg/mL and 20mg/mL for the antibacterial assay by agar diffusion method with activated cultured Staphylococcus aureus and Escherichia coli , incubated at 37oC for 24 hours . The results showed that these plants possess antibacterial activity on the basis of their zones of inhibition. Methanol extract of M. fragrans had a higher activity of 8-19mm on S. aureus than E. coli with 5-14mm range respectively. Ethylacetate fraction had the highest activity with 9-25mm on S. aureus, while chloroform fraction had the highest activity on E. coli with 8-18mm.  For T. vulgaris, the methanol extract had a higher activity of 6-18mm on E. coli than S. aureus of 4-17mm and for the fractions, n-hexane fraction had the highest activity of 7-20mm on S. aureus , while aqueous fraction had the highest activity of 5-18mm on E. coli, compared with zones of inhibition of 18mm against S. aureus  and 28mm against E. coli  for gentamycin of 2mg/mL which was the reference drug. Methanol extracts and fractions of M. fragrans seed and T. vulgaris leaf showed excellent activities on the gram positive and gram negative bacteria but the M. fragrans had a better activity than T. vulgaris.

scholarly journals STUDY OF VARIOUS FIVE EXTRACTS OF TRACHYSPERMUM AMMI SEEDS ON SELECTED FOUR GRAM-NEGATIVE COOKED FOOD SPOILAGE BACTERIAL STRAINS BY DISK DIFFUSION METHOD

2015 ◽  
Vol 3 (9SE) ◽  
pp. 1-3
Author(s):  
Usha Masih
Keyword(s):  
Antimicrobial Activity ◽  
Cold Water ◽  
Bacterial Species ◽  
Antibacterial Properties ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Disk Diffusion Method ◽  
Gram Negative ◽  
E Coli ◽  
Trachyspermum Ammi

Bacterial foodborne diseases are caused by consumption of foods contaminated with bacteria or their toxins. This study evaluated antibacterial properties of Trachyspermum ammi Acetone, ethanol, methanol, cold water and hard water extracts of spice (Ajowan) seeds against four gram negative strains of pathogenic foodborne bacteria, E. coli O157:H7   ATCC 43888, ATCC 25922, ATCC 8739 and ATCC 43895 that cause infection and intoxication. E. coli ATCC 43888 was observed to be highly susceptible to all extracts of ajowan with absolute zones of inhibition in the range of 16mm – 23mm in diameter. This study demonstrated that spice extracts have antimicrobial activity against food-borne bacterial species and should be considered as potential antibacterial agents for addition to ready meals. The spice contain high amount of secondary metabolites due to these metabolites they have high antimicrobial activity and it can be used as good bio- preserver and it can also use for medicinal purpose.

scholarly journals Antibacterial activities of ethanolic extract of four species of Rutaceae family

2020 ◽  
Vol 7 (3) ◽  
pp. 463-468
Author(s):  
Hong Thien Van ◽  
Dang Gia Man Nguyen ◽  
Nguyen Tuong An Quynh ◽  
Van Son Le
Keyword(s):  
Salmonella Enteritidis ◽  
Ethanolic Extract ◽  
Antibacterial Activities ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Ethanolic Extracts ◽  
Zones Of Inhibition ◽  
First Time

In this study, the antibacterial activity of ethanolic extract from the leaves of four Rutaceae species, including Acronychia pedunculata, Clausena excavata, Glycosmis pentaphylla and Luvunga scandens, were performed using the agar disk diffusion method for the first time. The ethanolic extracts from the leaves of A. pedunculata and G. pentaphylla were able to resist against all six bacterial strains with zones of inhibition for Bacillus cereus (17.3±2.1 mm, 20.8±1.0 mm) Staphylococcus aureus (8.5±0.5 mm, 17.6±0.3 mm) Escherichia coli (16.7±2.1 mm, 15.3±1.2 mm), Pseudomonas aeruginosa (11.7±0.6 mm, 14.0±1.7 mm), Salmonella enteritidis (22.3±0.6 mm, 24.6±0.5 mm) and Salmonella typhimurium (9.5±0.9 mm, 8.3±0.6 mm). On the other hand, the ethanolic extract of C. excavata leaf was resistant to B. cereus (12.3±0.6 mm), S. aureus (11.6±0.5 mm), E. coli (11.5±2.1 mm), P. aeruginosa (10.6±0.3 mm) while B. cereus (8.2±0.3 mm), S. aureus (9.3±0.6 mm), E. coli (8.5±0.5 mm) and S. typhimurium (8.3±0.6 mm) were inhibited by the ethanolic extract of L. scandens leaf. This study could provide necessary information for further application of these species in medicine.

Fabrication and Characterization of PANI/Ag Nanocomposites Voltammetric Sensor for Foodborne Bacteria

2020 ◽  
Vol 10 (1) ◽  
pp. 51-56
Author(s):  
V. Chaitra ◽  
V. Uma ◽  
S. Raja
Keyword(s):  
Indium Tin Oxide ◽  
Ag Nanoparticles ◽  
Low Cost ◽  
Detection Methods ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Foodborne Bacteria ◽  
Ito Glass

Introduction: Foodborne diseases are caused by consuming contaminated foods and/or beverages. Methods: Traditional detection methods for foodborne bacteria are sluggish and laborious. In this study, room temperature voltammetric sensors with low cost, specific, rapid and easy detection were fabricated using Polyaniline (PANI) and silver (Ag) nanoparticles. PANI films were coated on to the Indium Tin Oxide (ITO) glass substrate using electrochemical deposition technique. PANI surface was modified using Ag nanoparticles prepared by reduction method as Ag is one of the most powerful disinfectants against microbes. Both surface electron microscopy (SEM), X-ray diffraction (XRD) technique revealed the presence of Ag nanoparticles in the composites. The peaks observed in Fourier Transform Infrared Spectroscopy (FTIR) and optical absorption spectra are characteristics to PANI/Ag nanocomposites. Results: The antibacterial activities of the PANI/Ag nanocomposites were evaluated against Escherichia coli (E. Coli) (NCIM 2065), Staphylococcus aureus (S. aureus) (NCIM 2079) and Bacillus cereus (B. cereus) (NCIM 2106) using disk diffusion method. The composites showed better antibacterial activity due to the presence of Ag in comparison to pure PANI films. Conclusion: The sensor current for composites was found to increase with the presence of all the microbes. The sensitivity of the sensor was higher for E. coli bacteria among the other bacterial strains.

scholarly journals Synthesis, study of structure activity relationship and evaluation of biological activities of substituted (E)-2-Benzylidene-N-Methylhyrazinecarbothioamides

2017 ◽  
Vol 12 (4) ◽  
Author(s):  
Ganesamoorthy Thirunarayanan ◽  
R. Senbagam ◽  
M. Rajarajan ◽  
V. Manikandan ◽  
S. Balaji ◽  
...  
Keyword(s):  
Spectral Data ◽  
Biological Activities ◽  
Substituent Effects ◽  
Fungal Species ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Disk Diffusion Method ◽  
E Coli ◽  
Ft Ir ◽  
Good Agreement

A series of ten substituted (E)-2-benzylidene-N-methylhydrazinecarbothioamides were synthesized from 4-methyl-3-thiosemicarbazide with substituted benzaldehydes. All the synthesized compounds were in good agreement with elemental and spectral data (UV, FT-IR, 1H NMR and 13C NMR). The assigned UV λmax (nm), IR νC=N (cm-1), NMR δ1H (ppm) CH=N and δ13C (ppm) C=N spectral data of (E)-2-benzylidene-N-methylhydrazinecarbothioamides correlated with Hammett constants using single and multi-regression analysis. From the results of correlation analysis substituent effects on the spectral data have been discussed. The antibacterial activity of (E)-2-benzylidene-N-methylhydrazinecarbothioamides have been studied with three Gram-positive pathogenic bacterial strains namely (B. subtilis, S. aureus and S. pyogens) and two Gram-negative strains (E. coli and P. aeruginosa). The antifungal activity of (E)-2-benzylidene-N-methyl hydrazones studied with three fungal species (A. flavus, A. niger, T. viride) using disk diffusion method. 

scholarly journals Antibiotic Resistance of Uropathogens Isolated from Patients Hospitalized in District Hospital in Central Poland in 2020

Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 447
Author(s):  
Barbara Kot ◽  
Agata Grużewska ◽  
Piotr Szweda ◽  
Jolanta Wicha ◽  
Urszula Parulska
Keyword(s):  
Antibiotic Resistance ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Beta Lactamases ◽  
E Coli ◽  
Central Poland ◽  
Resistance Patterns ◽  
Extended Spectrum Beta Lactamases ◽  
Tract Infections

The aim of this study was to determine antibiotic resistance patterns and the prevalence of uropathogenes causing urinary tract infections (UTIs) in patients hospitalized in January–June 2020 in central Poland. Antimicrobial susceptibility testing was performed using the disk-diffusion method. Escherichia coli (52.2%), Klebsiella pneumoniae (13.7%), Enterococcus faecalis (9.3%), E. faecium (6.2%), and Proteus mirabilis (4,3%) were most commonly isolated from urine samples. E. coli was significantly more frequent in women (58.6%) (p = 0.0089) and in the age group 0–18, while K. pneumoniae was more frequent in men (24.4%) (p = 0.0119) and in individuals aged 40–60 and >60. Gram-negative species showed resistance to ampicillin. K. pneumoniae were resistant to amoxicillin plus clavulanic acid (75.0%), piperacillin plus tazobactam (76.2%), cefotaxime (76.2%), cefuroxime (81.0%), ciprofloxacin (81.0%), and trimethoprim plus sulphamethoxazole (81.0%). Carbapenems were effective against all E. coli and P. mirabilis. Some K. pneumoniae (13.6%) produced metallo-β-lactamases (MBLs). E. coli (22.6%), K. pneumoniae (81.8%), and all E. faecium were multidrug-resistant (MDR). Some E. coli (26.2%), K. pneumoniae (63.6%), and P. mirabilis (14.3%) isolates produced extended-spectrum beta-lactamases (ESBL). Vancomycin-resistant E. faecium was also found. This study showed that the possibilities of UTIs therapy using available antibiotics become limited due to the increasing number of antibiotic-resistant uropathogens.

scholarly journals Phenotypic Antimicrobial Susceptibility of Escherichia coli from Raw Meats, Ready-to-Eat Meats, and Their Related Samples in One Health Context

2021 ◽  
Vol 9 (2) ◽  
pp. 326
Author(s):  
Frederick Adzitey ◽  
Nurul Huda ◽  
Amir Husni Mohd Shariff
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Antimicrobial Susceptibility ◽  
Resistance Index ◽  
Diffusion Method ◽  
Resistant Bacteria ◽  
Disk Diffusion Method ◽  
E Coli ◽  
The Usa ◽  
Raw Meats

Meat is an important food source that can provide a significant amount of protein for human development. The occurrence of bacteria that are resistant to antimicrobials in meat poses a public health risk. This study evaluated the occurrence and antimicrobial resistance of E. coli (Escherichia coli) isolated from raw meats, ready-to-eat (RTE) meats and their related samples in Ghana. E. coli was isolated using the USA-FDA Bacteriological Analytical Manual and phenotypic antimicrobial susceptibility test was performed by the disk diffusion method. Of the 200 examined meats and their related samples, 38% were positive for E. coli. Notably, E. coli was highest in raw beef (80%) and lowest in RTE pork (0%). The 45 E. coli isolates were resistant ≥ 50% to amoxicillin, trimethoprim and tetracycline. They were susceptible to azithromycin (87.1%), chloramphenicol (81.3%), imipenem (74.8%), gentamicin (72.0%) and ciprofloxacin (69.5%). A relatively high intermediate resistance of 33.0% was observed for ceftriaxone. E. coli from raw meats, RTE meats, hands of meat sellers and working tools showed some differences and similarities in their phenotypic antimicrobial resistance patterns. Half (51.1%) of the E. coli isolates exhibited multidrug resistance. The E. coli isolates showed twenty-two different resistant patterns, with a multiple antibiotic resistance index of 0.0 to 0.7. The resistant pattern amoxicillin (A, n = 6 isolates) and amoxicillin-trimethoprim (A-TM, n = 6 isolates) were the most common. This study documents that raw meats, RTE meats and their related samples in Ghana are potential sources of antimicrobial-resistant E. coli and pose a risk for the transfer of resistant bacteria to the food chain, environment and humans.

scholarly journals Evaluation of extended spectrum beta lactamase enzymes prevalence in clinical isolates of Escherichia coli

2011 ◽  
Vol 2 (1) ◽  
pp. 8
Author(s):  
Ronak Bakhtiari ◽  
Jalil Fallah Mehrabadi ◽  
Hedroosha Molla Agamirzaei ◽  
Ailar Sabbaghi ◽  
Mohammad Mehdi Soltan Dallal
Keyword(s):  
Escherichia Coli ◽  
Disk Diffusion ◽  
Confirmatory Test ◽  
Diffusion Method ◽  
Multi Drug Resistance ◽  
Beta Lactamase ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Extended Spectrum

Resistance to b-lactam antibiotics by gramnegative bacteria, especially <em>Escherichia coli (E. coli)</em>, is a major public health issue worldwide. The predominant resistance mechanism in gram negative bacteria particularly <em>E. coli </em>is via the production of extended spectrum beta lactamase (ESBLs) enzymes. In recent years, the prevalence of b-lactamase producing organisms is increased and identification of these isolates by using disk diffusion method and no-one else is not satisfactory. So, this investigation focused on evaluating the prevalence of ESBL enzymes by disk diffusion method and confirmatory test (Combined Disk). Five hundred clinical samples were collected and 200 <em>E. coli </em>isolates were detected by standard biochemical tests. To performing initial screening of ESBLs was used from Disk diffusion method on <em>E. coli </em>isolates. A confirmation test (Combined Disk method) was performed on isolates of resistant to cephalosporin's indicators. Up to 70% isolates exhibited the Multi Drug Resistance phenotype. In Disk diffusion method, 128(64%) <em>E. coli </em>isolates which resistant to ceftazidime and cefotaxime while in Combined Disk, among 128 screened isolates, 115 (89.8%) isolates were detected as ESBLs producers. This survey indicate beta lactamase enzymes are playing a significant role in antibiotic resistance and correct detection of them in phenotypic test by using disk diffusion and combined Disk is essential for accurate recognition of ESBLs.

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