Antibacterial activity and in vitro cytotoxicity evaluation of alginate-AgNP fibers

Biopolymer nanocomposites containing metal nanoparticles have attracted much attention due to their excellent properties and broad applications. In this work, alginate fibers embedded with silver nanoparticles (AgNPs) were prepared. The as-obtained alginate-AgNP fibers exhibited antibacterial activity against both Gram microorganisms of model microbes Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive). A growth kinetic study with S. aureus and E. coli displayed the inhibition of bacterial growth at the logarithmic phase. The cytotoxic effect of the fibers in human cervical cancer (HeLa) cells was assessed by cell counting kit-8 (CCK-8) assay and flow cytometry. The as-prepared alginate-AgNP fibers, particularly with high amount and long treatment time, showed high cell-killing efficiency. These findings emphasize that such alginate-AgNP fibers with multifaceted biological activities are a promising material for applications in the textile or biomedical fields.

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Synthesis and Pharmacological Evaluation of 2-(4-(3 (Substituted Phenyl) Acryloyl) Phenoxy)-N, N Diphenylacetamides

Journal of Drug Delivery and Therapeutics ◽

10.22270/jddt.v10i5.4326 ◽

2020 ◽

Vol 10 (5) ◽

pp. 274-292

Author(s):

Rohit Kumar ◽

Sushil Kumar ◽

Mohammad Asif Khan

Keyword(s):

Antibacterial Activity ◽

Schiff Bases ◽

Biological Activities ◽

Diffusion Method ◽

Gram Positive ◽

Standard Drug ◽

E Coli ◽

Gram Positive Bacteria ◽

Pharmacological Evaluation

Recently a series of Schiff bases of diphenylamine derivatives have been synthesized and evaluated in vitro for their antibacterial activity against pathogenic both Gram-positive bacteria B. subtitles and Gram-negative bacteria E. coli using ciprofloxacin as standard drug at conc. of 50 μg/ml and 100 μg/ml. Literature review revels that chalcones possesses various biological activities like antimicrobial, antiviral, anti-inflammatory, anticancer and sedative etc. Therefore the present study was designed on synthesis and pharmacological evaluation of 2-(4-(3 (Substituted Phenyl) Acryloyl) Phenoxy)-N, N Diphenylacetamides. Target compound was synthesized by reaction of chloroacetylchloride with diphenylamine to afford 2-chloro-N, N-diphenylacetamide which further by reaction with substituted Chalcones and characterized following recrystallization and evaluated for anti-microbial potential through cup-diffusion method. In results, the target compounds were tested for activity against B. Subtilis, E.Coli and C. albicans. The chalcones having the lipophilic 4-chloro group (RKCT2) showed the greatest antimicrobial activity (zone of inhibition 20 & 22 mm against. B. subtilis, E. Coli, C. Albicans respectively. It suggests further researchers to go through anti-microbial evaluations against a more varieties of bacteria and fungi. Keywords: Schiff bases of diphenylamine derivatives, antibacterial activity, Gram-positive bacteria, 2-(4-(3 (Substituted Phenyl) Acryloyl) Phenoxy)-N, N Diphenylacetamides

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Hydrothermal Synthesis of Sr-doped Hydroxyapatite and Its Antibacterial Activity

Periodica Polytechnica Chemical Engineering ◽

10.3311/ppch.14062 ◽

2019 ◽

Vol 64 (1) ◽

pp. 54-60 ◽

Cited By ~ 2

Author(s):

Teodóra Nagyné-Kovács ◽

Boglárka Mészáros ◽

Mónika Molnár ◽

Mária Tolner ◽

István Endre Lukács ◽

...

Keyword(s):

Antibacterial Activity ◽

In Vitro Cytotoxicity ◽

Unit Cell ◽

Unit Cell Parameters ◽

Reaction Conditions ◽

Cell Parameters ◽

E Coli ◽

Lattice Constants ◽

Sample Characterization

In this study, we prepared hydroxyapatite (HAP) samples using hydrothermal method. We investigated the effect of reaction conditions such as phosphate excess applying 1.49 and 1.67 (as stoichiometric) Ca/P ratio, pH (9/ 10/ 11/ 12) and time (4/ 8/ 12/ 24 h). Sample characterization was carried out by XRD and SEM. The results showed, all samples had HAP structure, however, lower Ca/P ratio, larger reaction time and setting the pH to 10 increased the crystallinity. Then, we synthetized Sr-doped HAP samples, varying the Sr concentration using 2, 4, 6, 8 and 10 % Sr/ (Ca+Sr). The Sr content was revealed by EDX. Sr-incorporation did not change the obtained crystalline HAP phase but the unit cell parameters increased. We calculated lattice constants and found that a, b changed from 9.4310 Å to 9.4700 Å, c from 6.8819 Å to 6.9227 Å and the unit cell volume from 530.0951 Å3 to 537.6556 Å3 due to the larger ionic radius of Sr compared to Ca. The pure and doped samples had uniform, mostly needle-like morphology with 100-300 nm length and 25-100 nm. In vitro cytotoxicity tests revealed evident antibacterial activity in the case of doped samples compared to pure HAP against E. coli.

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In vitro synergistic potentials of novel antibacterial combination therapies against Salmonella Typhimurium, Escherichia coli and Staphylococcus aureus

10.21203/rs.2.9511/v1 ◽

2019 ◽

Author(s):

Md Akil Hossain ◽

Hae-Chul Park ◽

Kwang-jick Lee ◽

Sung-Won Park ◽

Seung-Chun Park ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Phenolic Compounds ◽

Phenolic Compound ◽

Virulence Factors ◽

In Vitro Cytotoxicity ◽

E Coli ◽

And Staphylococcus Aureus

Abstract Background: Bacteria have remarkable abilities to acquire resistance against antibiotics by several mechanisms. New strategies are needed to block the development of resistance and to prolong the life of traditional antibiotics. This study aimed to increase the efficacy of existing antibiotics by combining them with the opportunistic phenolic compound gallic acid (GA) and its derivatives. Fractional inhibitory concentration (FIC) indexes of phenolic compound-antibiotic combinations against Salmonella enterica serovar Typhimurium, Escherichia coli and Staphylococcus aureus were determined. Based on the FIC indexes and clinical importance, 3 combinations were selected to evaluate their effects on the virulence factors of these bacteria. The in vitro cytotoxicity of GA and hamamelitannin in the Rattus norvegicus (IEC-6) cell line were evaluated. Results: Phenolic compounds demonstrated considerable antibacterial effects as the minimum inhibitory concentrations (MICs) of epigallocatechin, GA and hamamelitannin found against different strains were (32–1024), (128–1024) and (512–≥2048) μg/mL, respectively. The FIC indexes of the combined antibacterials against these strains were 0.281–1.016. The ultrastructural morphology and time-kill assays showed that the GA-ceftiofur combination, and hamamelitannin-erythromycin and GA-ampicillin combinations more efficiently inhibited the growth of S. Typhimurium and E. coli, respectively, compared to the individual antibiotics. Biofilm viability and the swimming and swarming motilities of S. Typhimurium in the presence of GA-ceftiofur and E. coli in the presence of the hamamelitannin-erythromycin and GA-ampicillin combinations were more competently inhibited than individual antimicrobials. The 50% inhibitory concentrations (IC50) of GA and hamamelitannin in IEC-6 cells were 564.55 μM and 988.54 μM, respectively. Conclusions: The phenolic compounds increase the efficacy of existing antibiotics might be by disrupting virulence factors. We can conclude that these antibacterial combinations are safe and can be potential medications to treat S. Typhimurium, E. coli and S. aureus infections in animals and humans. Further study to confirm this effect in in vivo system and to determine the precise mechanism of action should be undertaken to establish these combinations as medications.

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Improved Bacteriostatic and Anticorrosion Effects of Polycaprolactone/Chitosan Coated Magnesium via Incorporation of Zinc Oxide

Materials ◽

10.3390/ma14081930 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1930

Author(s):

Hamid Reza Bakhsheshi-Rad ◽

Esah Hamzah ◽

Wong See Ying ◽

Mahmood Razzaghi ◽

Safian Sharif ◽

...

Keyword(s):

Zinc Oxide ◽

Antibacterial Activity ◽

Corrosion Resistance ◽

Composite Coating ◽

Interaction Mechanism ◽

Cell Interaction ◽

Orthopedic Implant ◽

E Coli ◽

And Staphylococcus Aureus

Magnesium has been recognized as a groundbreaking biodegradable biomaterial for implant applications, but its use is limited because it degrades too quickly in physiological solutions. This paper describes the research on the influence of polycaprolactone (PCL)/chitosan (CS)/zinc oxide (ZnO) composite coating (PCL/CS/ZnO) on the corrosion resistance and antibacterial activity of magnesium. The PCL/CS film presented a porous structure with thickness of about 40–50 μm, while after incorporation of ZnO into the PCL/CS, a homogenous film without pores and defects was attained. The ZnO embedded in PCL/CS enhanced corrosion resistance by preventing corrosive ions diffusion in the magnesium substrate. The corrosion, antibacterial, and cell interaction mechanism of the PCL/CS/ZnO composite coating is discussed in this study. In vitro cell culture revealed that the PCL/CS coating with low loaded ZnO significantly improved cytocompatibility, but coatings with high loaded ZnO were able to induce some cytotoxicity osteoblastic cells. It was also found that enhanced antibacterial activity of the PCL/CS/ZnO coating against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria, while less significant antibacterial activity was detected for uncoated Mg and PCL/CS coating. Based on the results, the PCL/CS coatings loaded with low ZnO content may be recommended as a candidate material for biodegradable Mg-based orthopedic implant applications.

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Synthesis and Cytotoxicity of New Mannich Bases of 6-[3-(3,4,5-Trimetoxyphenyl)-2- propenoyl]-2(3H)-Benzoxazolone

Letters in Drug Design & Discovery ◽

10.2174/1570180816666190730164952 ◽

2020 ◽

Vol 17 (4) ◽

pp. 512-517

Author(s):

Ognyan Ivanov Petrov ◽

Yordanka Borisova Ivanova ◽

Mariana Stefanova Gerova ◽

Georgi Tsvetanov Momekov

Keyword(s):

Tumor Cell ◽

Cell Lines ◽

Biological Activities ◽

Human Tumor ◽

Mannich Bases ◽

In Vitro Cytotoxicity ◽

Tumor Cell Lines ◽

Human Tumor Cell ◽

Human Tumor Cell Lines

Background: Chemotherapy is one of the mainstays of cancer treatment, despite the serious side effects of the clinically available anticancer drugs. In recent years increasing attention has been directed towards novel agents with improved efficacy and selectivity. Compounds with chalcone backbone have been reported to possess various biological activities such as anticancer, antimicrobial, anti-inflammatory, analgesic, antioxidant, etc. It was reported that aminomethylation of hydroxy chalcones to the corresponding Mannich bases increased their cytotoxicity. In this context, our interest has been focused on the design and synthesis of the so-called multi-target molecules, containing two or more pharmacophore fragments. Methods: A series of Mannich bases were synthesized by the reaction between 6-[3-(3,4,5- trimethoxyphenyl)-2-propenoyl]-2(3Н)-benzoxazolone, formaldehyde, and a secondary amine. The structures of the compounds were confirmed by elemental analysis, IR and NMR spectra. The new Mannich bases were evaluated for their in vitro cytotoxicity against a panel of human tumor cell lines, including BV-173, SKW-3, K-562, HL-60, HD-MY-Z and MDA-MB-231. The effects of selected compounds on the cellular levels of glutathione (GSH) were determined. Results: The new compounds 4a-e exhibited concentration-dependent cytotoxic effects at micromolar concentrations in MTT-dye reduction assay against a panel of human tumor cell lines, similar to those of starting chalcone 3. The tested agents led to concentration - dependent depletion of cellular GSH levels, whereby the effects of the chalcone prototype 3 and its Mannich base-derivatives were comparable. Conclusion: The highest chemosensitivity to the tested compounds was observed in BV- 173followed by SKW-3 and HL-60 cell lines.

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In Vitro Antibacterial activity of ethanolic extract of Myrsine africana against laboratory Strains of Pathogenic Organisms

International Journal of Bioassays ◽

10.21746/ijbio.2016.04.0011 ◽

2016 ◽

Vol 5 (04) ◽

pp. 4512

Author(s):

Jackie K. Obey ◽

Anthoney Swamy T* ◽

Lasiti Timothy ◽

Makani Rachel

Keyword(s):

Antibacterial Activity ◽

Minimum Inhibitory Concentration ◽

Inhibitory Concentration ◽

Ethanolic Extract ◽

Ethanol Extract ◽

E Coli ◽

Zones Of Inhibition ◽

In Vitro Antibacterial Activity ◽

Myrsine Africana

The determination of the antibacterial activity (zone of inhibition) and minimum inhibitory concentration of medicinal plants a crucial step in drug development. In this study, the antibacterial activity and minimum inhibitory concentration of the ethanol extract of Myrsine africana were determined for Escherichia coli, Bacillus cereus, Staphylococcus epidermidis and Streptococcus pneumoniae. The zones of inhibition (mm±S.E) of 500mg/ml of M. africana ethanol extract were 22.00± 0.00 for E. coli,20.33 ±0.33 for B. cereus,25.00± 0.00 for S. epidermidis and 18. 17±0.17 for S. pneumoniae. The minimum inhibitory concentration(MIC) is the minimum dose required to inhibit growth a microorganism. Upon further double dilution of the 500mg/ml of M. africana extract, MIC was obtained for each organism. The MIC for E. coli, B. cereus, S. epidermidis and S. pneumoniae were 7.81mg/ml, 7.81mg/ml, 15.63mg/ml and 15.63mg/ml respectively. Crude extracts are considered active when they inhibit microorganisms with zones of inhibition of 8mm and above. Therefore, this study has shown that the ethanol extract of M. africana can control the growth of the four organisms tested.

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Importance of beta-lactamase inhibitor pharmacokinetics in the pharmacodynamics of inhibitor-drug combinations: studies with piperacillin-tazobactam and piperacillin-sulbactam.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.41.4.721 ◽

1997 ◽

Vol 41 (4) ◽

pp. 721-727 ◽

Cited By ~ 33

Author(s):

P D Lister ◽

A M Prevan ◽

C C Sanders

Keyword(s):

Antibacterial Activity ◽

Critical Concentration ◽

Specific Inhibitor ◽

Logarithmic Phase ◽

Critical Ratio ◽

Beta Lactamase ◽

Beta Lactam ◽

Dosing Regimens ◽

Lactamase Inhibitor

An in vitro pharmacokinetic model was used to study the pharmacodynamics of piperacillin-tazobactam and piperacillin-sulbactam against gram-negative bacilli producing plasmid-encoded beta-lactamases. Logarithmic-phase cultures were exposed to peak antibiotic concentrations observed in human serum after the administration of intravenous doses of 3 g of piperacillin and 0.375 g of tazobactam or 0.5 g of sulbactam. Piperacillin and inhibitor were either dosed simultaneously or piperacillin was dosed sequentially 0.5 h after dosing with the inhibitor. In studies with all four test strains, the pharmacodynamics observed after simultaneous dosing were similar to those observed with the sequential regimen. Since the ratio between piperacillin and tazobactam was in constant fluctuation after sequential dosing, these data suggest that the pharmacodynamics of the piperacillin-inhibitor combinations were not dependent upon maintenance of a critical ratio between the components. Furthermore, when regrowth was observed, the time at which bacterial counts began to increase was similar between the simultaneous and sequential dosing regimens. Since the pharmacokinetics of the inhibitors were the same for all regimens, these data suggest that the length of time that the antibacterial activity was maintained over the dosing interval with these combinations was dictated by the pharmacokinetics of the beta-lactamase inhibitor in the combination. The antibacterial activity of the combination appeared to be lost when the amount of inhibitor available fell below some critical concentration. This critical concentration varied depending upon the type and amount of enzyme produced, as well as the specific inhibitor used. These results indicate that the antibacterial activity of drug-inhibitor combinations, when dosed at their currently recommended ratios, is more dependent on the pharmacokinetics of the inhibitor than on those of the beta-lactam drug.

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The Multifunctional Sactipeptide Ruminococcin C1 Displays Potent Antibacterial Activity In Vivo as Well as Other Beneficial Properties for Human Health

International Journal of Molecular Sciences ◽

10.3390/ijms22063253 ◽

2021 ◽

Vol 22 (6) ◽

pp. 3253

Author(s):

Clarisse Roblin ◽

Steve Chiumento ◽

Cédric Jacqueline ◽

Eric Pinloche ◽

Cendrine Nicoletti ◽

...

Keyword(s):

Antibacterial Activity ◽

Human Health ◽

Biological Activities ◽

Resistant Bacteria ◽

Modified Peptides ◽

The 1960S ◽

Conventional Antibiotics ◽

Clinical Potential

The world is on the verge of a major antibiotic crisis as the emergence of resistant bacteria is increasing, and very few novel molecules have been discovered since the 1960s. In this context, scientists have been exploring alternatives to conventional antibiotics, such as ribosomally synthesized and post-translationally modified peptides (RiPPs). Interestingly, the highly potent in vitro antibacterial activity and safety of ruminococcin C1, a recently discovered RiPP belonging to the sactipeptide subclass, has been demonstrated. The present results show that ruminococcin C1 is efficient at curing infection and at protecting challenged mice from Clostridium perfringens with a lower dose than the conventional antibiotic vancomycin. Moreover, antimicrobial peptide (AMP) is also effective against this pathogen in the complex microbial community of the gut environment, with a selective impact on a few bacterial genera, while maintaining a global homeostasis of the microbiome. In addition, ruminococcin C1 exhibits other biological activities that could be beneficial for human health, as well as other fields of applications. Overall, this study, by using an in vivo infection approach, confirms the antimicrobial clinical potential and highlights the multiple functional properties of ruminococcin C1, thus extending its therapeutic interest.

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Chemical Composition and Antibacterial and Antioxidant Activity of a Citrus Essential Oil and Its Fractions

Molecules ◽

10.3390/molecules26102888 ◽

2021 ◽

Vol 26 (10) ◽

pp. 2888

Author(s):

Carmen M. S. Ambrosio ◽

Gloria L. Diaz-Arenas ◽

Leidy P. A. Agudelo ◽

Elena Stashenko ◽

Carmen J. Contreras-Castillo ◽

...

Keyword(s):

Antioxidant Activity ◽

Antibacterial Activity ◽

Chemical Composition ◽

Essential Oil ◽

Biological Activities ◽

E Coli ◽

Beneficial Bacterium ◽

Minor Compounds ◽

Antibacterial And Antioxidant Activity ◽

High Relative Amount

Essential oils (EOs) from Citrus are the main by-product of Citrus-processing industries. In addition to food/beverage and cosmetic applications, citrus EOs could also potentially be used as an alternative to antibiotics in food-producing animals. A commercial citrus EO—Brazilian Orange Terpenes (BOT)—was fractionated by vacuum fractional distillation to separate BOT into various fractions: F1, F2, F3, and F4. Next, the chemical composition and biological activities of BOT and its fractions were characterized. Results showed the three first fractions had a high relative amount of limonene (≥10.86), even higher than the whole BOT. Conversely, F4 presented a larger relative amount of BOT’s minor compounds (carvone, cis-carveol, trans-carveol, cis-p-Mentha-2,8-dien-1-ol, and trans-p-Mentha-2,8-dien-1-ol) and a very low relative amount of limonene (0.08–0.13). Antibacterial activity results showed F4 was the only fraction exhibiting this activity, which was selective and higher activity on a pathogenic bacterium (E. coli) than on a beneficial bacterium (Lactobacillus sp.). However, F4 activity was lower than BOT. Similarly, F4 displayed the highest antioxidant activity among fractions (equivalent to BOT). These results indicated that probably those minor compounds that detected in F4 would be more involved in conferring the biological activities for this fraction and consequently for the whole BOT, instead of the major compound, limonene, playing this role exclusively.

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In vitro cytotoxicity of Aspilia pluriseta Schweinf. extract fractions

BMC Research Notes ◽

10.1186/s13104-021-05472-4 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Sospeter N. Njeru ◽

Jackson M. Muema

Keyword(s):

Biological Activities ◽

Vero Cells ◽

In Vitro Cytotoxicity ◽

Root Extract ◽

Lack Of Information ◽

Information Gap ◽

Diphenyltetrazolium Bromide ◽

Potential Use

Abstract Objectives We and others have shown that Aspilia pluriseta is associated with various biological activities. However, there is a lack of information on its cytotoxicity. This has created an information gap about the safety of A. pluriseta extracts. As an extension to our recent publication on the antimicrobial activity and the phytochemical characterization of A. pluriseta root extracts, here we report on cytotoxicity of tested solvent fractions. We evaluated the potential cytotoxicity of these root extract fractions on Vero cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results We show that all solvent extract fractions (except methanolic solvent fractions) had cytotoxic concentration values that killed 50% of the Vero cells (CC50) greater than 20 µg/mL and selectivity index (SI) greater than 1.0. Taken together, we demonstrate that, A. pluriseta extract fractions’ earlier reported bioactivities are within the acceptable cytotoxicity and selective index limits. This finding scientifically validates the potential use of A. pluriseta in the discovery of safe therapeutics agents.

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