DDA (degree of deacetylation) and pH-dependent antibacterial properties of chitin nanofibers against Escherichia coli

Infection is a disease caused by the presence of pathogenic microbes, including Staphylococcus aureus and Escherichia coli. Garlic (Allium sativum L.) has chemical contents such as allicin, alkaloids, flavonoids, saponins, tannins, and steroids, which can function as an antibacterial against Staphylococcus aureus and Escherichia coli. This study aims to determine the antibacterial properties of garlic extract powder against Staphylococcus aureus and Escherichia coli. This research is the initial stage of the development of herbal medicines to treat Staphylococcus aureus and Escherichia coli infections. The antibacterial activity test was carried out by the liquid dilution method. The concentrations used were 30 mg/mL, 40 mg/mL, 50 mg/mL, 60 mg/mL and 70 mg/mL. The results showed that the Minimum Inhibitory Concentration (MIC) against Staphylococcus aureus and Escherichia coli was 40 mg/mL and 50 mg / mL. Minimum Bactericidal Concentration (MBC) results for Staphylococcus aureus and Escherichia coli are 50 mg/mL and 70 mg/mL. Based on the Simple Linear Regression test, the R2 value of Staphylococcus aureus and Escherichia coli is 0.545 and 0.785, so it can be concluded that there is an effect of garlic extract powder on the growth of Staphylococcus aureus and Escherichia coli by 54.5% and 78.5%. Garlic (Allium sativum L.) extract powder has potential as herbal medicine against bacterial infections but requires further research to determine its effect in vivo.

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Improved cytocompatibility and antibacterial properties of zinc-substituted brushite bone cement based on β-tricalcium phosphate

Journal of Materials Science Materials in Medicine ◽

10.1007/s10856-021-06575-x ◽

2021 ◽

Vol 32 (9) ◽

Author(s):

Inna V. Fadeeva ◽

Margarita A. Goldberg ◽

Ilya I. Preobrazhensky ◽

Georgy V. Mamin ◽

Galina A. Davidova ◽

...

Keyword(s):

Escherichia Coli ◽

Tricalcium Phosphate ◽

Bacterial Resistance ◽

Antibacterial Properties ◽

Modern Medicine ◽

Physiological Solution ◽

Final Phase ◽

Bone Replacement ◽

Challenging Tasks ◽

Murine Fibroblast

AbstractFor bone replacement materials, osteoconductive, osteoinductive, and osteogenic properties are desired. The bacterial resistance and the need for new antibacterial strategies stand among the most challenging tasks of the modern medicine. In this work, brushite cements based on powders of Zinc (Zn) (1.4 wt%) substituted tricalcium phosphate (β-TCP) and non-substituted β-TCP were prepared and investigated. Their initial and final phase composition, time of setting, morphology, pH evolution, and compressive strength are reported. After soaking for 60 days in physiological solution, the cements transformed into a mixture of brushite and hydroxyapatite. Antibacterial activity of the cements against Enterococcus faecium, Escherichia coli, and Pseudomonas aeruginosa bacteria strains was attested. The absence of cytotoxicity of cements was proved for murine fibroblast NCTC L929 cells. Moreover, the cell viability on the β-TCP cement containing Zn2+ ions was 10% higher compared to the β-TCP cement without zinc. The developed cements are perspective for applications in orthopedics and traumatology.

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The Effect of TiO2 additives on the antibacterial properties (Escherichia coli and Staphylococcus aureus) of glaze on ceramic tiles

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/980/1/012011 ◽

2021 ◽

Vol 980 ◽

pp. 012011

Author(s):

E Maryani ◽

N S Nurjanah ◽

E P Hadisantoso ◽

R B Wijayanti

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Properties ◽

Ceramic Tiles ◽

And Staphylococcus Aureus

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pH-dependent activation of cytokinesis modulates Escherichia coli cell size

PLoS Genetics ◽

10.1371/journal.pgen.1008685 ◽

2020 ◽

Vol 16 (3) ◽

pp. e1008685 ◽

Cited By ~ 2

Author(s):

Elizabeth A. Mueller ◽

Corey S. Westfall ◽

Petra Anne Levin

Keyword(s):

Escherichia Coli ◽

Cell Size ◽

Coli Cell ◽

Ph Dependent

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pH-Dependent Catabolic Protein Expression during Anaerobic Growth of Escherichia coli K-12

Journal of Bacteriology ◽

10.1128/jb.186.1.192-199.2004 ◽

2004 ◽

Vol 186 (1) ◽

pp. 192-199 ◽

Cited By ~ 65

Author(s):

Elizabeth Yohannes ◽

D. Michael Barnhart ◽

Joan L. Slonczewski

Keyword(s):

Escherichia Coli ◽

Ph Regulation ◽

Metabolic Enzymes ◽

Anaerobic Growth ◽

High Ph ◽

E Coli ◽

Catabolic Enzymes ◽

Periplasmic Proteins ◽

Ph Dependent ◽

K 12

ABSTRACT During aerobic growth of Escherichia coli, expression of catabolic enzymes and envelope and periplasmic proteins is regulated by pH. Additional modes of pH regulation were revealed under anaerobiosis. E. coli K-12 strain W3110 was cultured anaerobically in broth medium buffered at pH 5.5 or 8.5 for protein identification on proteomic two-dimensional gels. A total of 32 proteins from anaerobic cultures show pH-dependent expression, and only four of these proteins (DsbA, TnaA, GatY, and HdeA) showed pH regulation in aerated cultures. The levels of 19 proteins were elevated at the high pH; these proteins included metabolic enzymes (DhaKLM, GapA, TnaA, HisC, and HisD), periplasmic proteins (ProX, OppA, DegQ, MalB, and MglB), and stress proteins (DsbA, Tig, and UspA). High-pH induction of the glycolytic enzymes DhaKLM and GapA suggested that there was increased fermentation to acids, which helped neutralize alkalinity. Reporter lac fusion constructs showed base induction of sdaA encoding serine deaminase under anaerobiosis; in addition, the glutamate decarboxylase genes gadA and gadB were induced at the high pH anaerobically but not with aeration. This result is consistent with the hypothesis that there is a connection between the gad system and GabT metabolism of 4-aminobutanoate. On the other hand, 13 other proteins were induced by acid; these proteins included metabolic enzymes (GatY and AckA), periplasmic proteins (TolC, HdeA, and OmpA), and redox enzymes (GuaB, HmpA, and Lpd). The acid induction of NikA (nickel transporter) is of interest because E. coli requires nickel for anaerobic fermentation. The position of the NikA spot coincided with the position of a small unidentified spot whose induction in aerobic cultures was reported previously; thus, NikA appeared to be induced slightly by acid during aeration but showed stronger induction under anaerobic conditions. Overall, anaerobic growth revealed several more pH-regulated proteins; in particular, anaerobiosis enabled induction of several additional catabolic enzymes and sugar transporters at the high pH, at which production of fermentation acids may be advantageous for the cell.

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Synthesis of CoFe 2 O 4 /BiOI Nanocomposite: Effects on Staphylococcus aureus, Escherichia coli, Pseudomonas Aeruginosa and Bacillus Cereus

10.21203/rs.3.rs-842251/v1 ◽

2021 ◽

Author(s):

Davood Gheidari ◽

Morteza Mehrdad ◽

Saloomeh Maleki ◽

Samanesadat Hosseini

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Bacillus Cereus ◽

Antibacterial Properties ◽

Limited Area ◽

X Ray Diffraction ◽

X Ray ◽

Inhibition Concentration ◽

Resolution Mapping

Abstract With the increase of general knowledge and the advancement of science and technology, antibacterial substances were used more than antibiotics. In our current study, the antibacterial virtues of CFO/BiOI nanocomposite were investigated due to its high importance on Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus cereus. MIC, MBC , Disk Diffusion and IC50 tests Cefalotin (CF), Amoxicillin (AMX), Gentamicin (GM), Trimethoprim-sulphamethoxazole (SXT) and Ceftriaxone (CRO) antibiotics in concentration 30W, 10i, 10t , 25h and 30 were used to find the antibacterial properties of the synthesized nanocomposite, respectively. For the synthesis of nanocomposites polyethylene glycol (PEG) and sulfonic acid was used as a solvent. It is noteworthy that the synthesis was performed by heat dissolution method without the presence of surfactant. Also, various techniques such as X-Ray Diffraction(XRD), Scanning Electron Microscope (SEM), High resolution mapping and Energy Dispersive X-ray spectroscopy (EDAX) have been used to determine the properties of produced nanocomposites. SEM test results showed that the formed nanoparticles were globular and their size was limited area of 22 to 34 nm. The results showed CFO / BiOI nanocomposite exhibits strong significant biological activity against Bacillus cereus. The results of MBC (Minimum Bactericidal Concentration) and MIC (Minimum Inhibition Concentration) tests for CFO/BiOI nanocomposites on bacteria were examined in the range of 0.12-0.48 mg/ml and 0.06 to 0.24 mg/ml respectively. According to the results, the minimum IC50 value was determined at a concentration of 0.061 mg/ml. On the other hand, the most resisting and susceptible bacteria in this method were Pseudomonas aeruginosa and Bacillus cereus, respectively. These findings are identical to those of a prior study on CoFe2O4 nanoparticles antibacterial properties. MBC of the nanocomposites, 50 µl from all the tubes that showed no obvious bacterial growth were distributed on BHI agar plates and incubated for 24 h at 37 ◦C. The MBC endpoint is defined as the lowest concentration which killed 98% of the bacterial population.

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Efficacy of Liquid Protein Hydrolysate from Chicken Feather by Pseudomonas sp. on the Growth of Cucumis sativus

Proceedings International ◽

10.33263/proceedings021.016016 ◽

2020 ◽

Vol 2 (1) ◽

pp. 16

Keyword(s):

Escherichia Coli ◽

Enzymatic Activity ◽

Cucumis Sativus ◽

Protein Hydrolysate ◽

Antibacterial Properties ◽

Full Potential ◽

Pseudomonas Sp ◽

Chicken Feather ◽

Chicken Feathers ◽

High Enzymatic Activity

Keratin, which made up the chicken feather, is difficult to be broken down by the proteolytic enzyme. Annually, millions of tons of chicken feathers are disposed of worldwide as waste without realizing the high protein content in the feather. Due to the presence of keratinase from keratinolytic bacteria, chicken feathers are disposed of together with poultry excreta. Therefore, this study is conducted to study the ability of liquid protein hydrolysate produced by bacteria in poultry excreta to utilize into biofertilizing and biocontrol. Keratinolytic bacteria are identified from poultry excreta by screening. The isolated enzyme was optimized in various conditions such as different pH, temperature, and feather concentration as well as nitrogen and carbon sources. Enzymatic activity increased gradually from 1% to 5% in carbon and nitrogen sources. Liquid protein hydrolysate was used to study the biofertilizing ability on the growth of Cucumis sativus and antibacterial effect on Escherichia coli. Pseudomonas sp. has the capability to degrade the feather on 10th day due to the high enzymatic activity. Pseudomonas sp. shows high enzymatic activity at 37⁰C, pH 8, and feather concentration at 0.5%. The chlorophyll estimation shows a p-value<0.05 after being treated with liquid protein hydrolysate. Liquid protein hydrolysate promoted the growth of Cucumis sativus as well as Pseudomonas sp. The antibacterial properties can also be seen against Escherichia coli. In a nutshell, chicken feather produces liquid protein hydrolysate, which has biofertilizing properties. The full potential of liquid hydrolysate can be understood with further analysis of peptide in protein hydrolysate.

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Evaluation of Nanocomposite Made of Polylactic Acid and Nanocellulose from Carrot Pomace Modified with Silver Nanoparticles

Polymers ◽

10.3390/polym12040812 ◽

2020 ◽

Vol 12 (4) ◽

pp. 812 ◽

Cited By ~ 1

Author(s):

Monika Szymańska-Chargot ◽

Monika Chylińska ◽

Piotr M. Pieczywek ◽

Anna Walkiewicz ◽

Giorgia Pertile ◽

...

Keyword(s):

Escherichia Coli ◽

Mechanical Properties ◽

Carbon Dioxide ◽

Silver Nanoparticles ◽

Polylactic Acid ◽

Cellulose Nanofibrils ◽

Antibacterial Properties ◽

Young Modulus ◽

Transmission Rates ◽

Degradation Temperature

In this research, it was proposed to use carrot cellulose nanofibrils (CCNF) isolated from carrot pomace modified with silver nanoparticles (AgNPs) as a filler of polylactic acid (PLA) composites matrix. The new procedure was based on two steps: first, the preparation of nanocellulose modified with metal nanoparticles, and then the combination with PLA. Two concentrations—0.25 mM and 2 mM—of AgNO3 were used to modify CCNF. Then, PLA was mixed with the filler (CCNF/AgNPs) in two proportions 99:1 and 96:4. The influence of CCNF/AgNPs on mechanical, hydrophilic, thermal, and antibacterial properties of obtained nanocomposites was evaluated. The greatest improvement of mechanical properties was observed for composite containing CCNF with 2 mM of AgNPs, which obtained the lowest Young modulus and highest strain at break. The degradation temperature was lower for PLA with CCNF/AgNPs, but crystallization temperature wasn’t influenced. The addition of CCNF/AgNPs also increased hydrophilicity. The transmission rates of oxygen, nitrogen, and carbon dioxide also increased after the addition of CCNF/AgNPs to PLA. The antibacterial function against Escherichia coli and Bacillus cereus was obtained after the addition of AgNPs but only at the contact surface with the material made, suggesting the lack of migration of nanoparticles from the composite.

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Ex vivo antibacterial properties of rufloxacin compared with those of norfloxacin in a study with healthy volunteers.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.40.1.17 ◽

1996 ◽

Vol 40 (1) ◽

pp. 17-21 ◽

Cited By ~ 5

Author(s):

L Aguilar ◽

I P Balcabao ◽

P Salvá ◽

M Martín ◽

J Costa ◽

...

Keyword(s):

Escherichia Coli ◽

Clinical Trial ◽

Ex Vivo ◽

Antibacterial Properties ◽

Adult Males ◽

E Coli ◽

Crossover Phase ◽

Uncomplicated Cystitis ◽

And Staphylococcus Aureus ◽

Early Sample

Twelve adult males participated in a randomized crossover phase I clinical trial comparing serum bactericidal titers (SBTs), urine bactericidal titers (UBTs), and urine killing rates (UKRs) against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213, after the administration of single 400-mg doses of rufloxacin and norfloxacin at different times up to 72 h postdose. SBTs were significantly higher (P < 0.05) against E. coli from 8 to 48 h and against S. aureus from 4 to 24 h with rufloxacin. UBTs for E. coli were higher (P < 0.05) for norfloxacin at early sample times (0 to 8 h) but higher for rufloxacin (P < 0.05) at sample times from 16 h on for both E. coli and S. aureus. Similar UKRs were obtained for both quinolones for 0 to 2 h and 8 to 12 h, but the UKR was maintained for 72 h with rufloxacin. The high and sustained mean levels of rufloxacin in urine (> 35 micrograms/ml), median UBTs (> 32 for E. coli and 16 for S. aureus) and UKRs for E. coli suggest prolonged urine antibacterial activity (for at least 72 h) and its use as a single 400-mg dose in the treatment of uncomplicated cystitis.

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An Investigation on the Electrochemical Behavior and Antibacterial and Cytotoxic Activity of Nickel Trithiocyanurate Complexes

Materials ◽

10.3390/ma13071782 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1782

Author(s):

Amir M. Ashrafi ◽

Pavel Kopel ◽

Lukas Richtera

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Cyclic Voltammetry ◽

Antibacterial Activity ◽

Cytotoxic Activity ◽

Cell Lines ◽

Electrochemical Behavior ◽

Antibacterial Properties ◽

Redox Behavior ◽

Electrochemical Redox

The electrochemical redox behavior of three trinuclear Ni(II) complexes [Ni3(abb)3(H2O)3(µ-ttc)](ClO4)3 (1), [Ni3(tebb)3(H2O)3(µ-ttc)](ClO4)3·H2O (2), and [Ni3(pmdien)3(µ-ttc)](ClO4)3 (3), where abb = 1-(1H-benzimidazol-2-yl)-N-(1H-benzimidazol-2-ylmethyl)methan-amine, ttcH3 = trithiocyanuric acid, tebb = 2-[2-[2-(1H-benzimidazol-2-yl)ethylsulfanyl]ethyl]-1H-benzimidazole, and pmdien = N,N,N′,N″,N″-pentamethyldiethylenetriamine is reported. Cyclic voltammetry (CV) was applied for the study of the electrochemical behavior of these compounds. The results confirmed the presence of ttc and nickel in oxidation state +2 in the synthesized complexes. Moreover, the antibacterial properties and cytotoxic activity of complex 3 was investigated. All the complexes show antibacterial activity against Staphylococcus aureus and Escherichia coli to different extents. The cytotoxic activity of complex 3 and ttcNa3 were studied on G-361, HOS, K-562, and MCF7 cancer cell lines. It was found out that complex 3 possesses the cytotoxic activity against the tested cell lines, whereas ttcNa3 did not show any cytotoxic activity.

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