Antimicrobial activity of silver-coated hollow poly(methylmethacrylate) microspheres for water decontamination

Abstract Background Growing microbial resistance towards the existing antimicrobial materials appears as the greatest challenge for the scientific community and development of new antimicrobial materials has become an important research objective. Results In this work, antimicrobial activity of silver-coated hollow poly(methylmethacrylate) microspheres (PMB) having a diameter of 20–80 µm was evaluated against two bacterial strains, Gram-positive Bacillus subtilis (MTCC 1305) and Gram-negative Escherichia coli (MTCC 443). The polymeric PMMA microspheres were synthesized by solvent evaporation technique and were further coated with silver (Ag) under microwave irradiation on their outer surface using an electroless plating technique. It was observed that Ag was uniformly coated on the surface of microspheres. Characterization of the coated microspheres was performed using optical microscope (OMS), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), UV–Vis spectroscopy, FTIR spectroscopy and thermogravimetric analysis (TGA) techniques. We have shown that the silver-coated microspheres were potent bactericidal material for water as they are highly active against the tested microorganisms. The results of the antibacterial tests indicated that APMB particles showed enhanced inhibition rate for both Gram-positive and Gram-negative bacteria and also exhibited dose-dependent antibacterial ability. The diameters of zone of inhibition were14.3 ± 0.2 mm against B. subtilis and 15.2 ± 0.9 mm against E. coli at a concentration of 8 mg. At this concentration, total removal of both Bacillus subtilis and Escherichia coli was observed. The results of shake flask technique for a concentration of 8 mg showed no bacterial presence after 24 h in both the cases. In other words, the material acted efficiently in bringing down the bacterial count to zero level for the tested strains. During the experiments, we have also confirmed that use of this material for water disinfection does not cause leaching of silver ion in to the water solution. The material can be successfully regenerated by backwashing with water. Conclusions Considering the cost-effective synthesis, ability to regenerate and very low level of leaching of the material, it can be projected as an advanced material for water disinfection and antimicrobial application.

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Spatial Structure and Antimicrobial Activity of Cyclopropane Derivative of Limonene

Natural Product Communications ◽

10.1177/1934578x1801300401 ◽

2018 ◽

Vol 13 (4) ◽

pp. 1934578X1801300

Author(s):

Daniyar Sadyrbekov ◽

Timur Saliev ◽

Yuri Gatilov ◽

Ivan Kulakov ◽

Roza Seidakhmetova ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antimicrobial Activity ◽

Bacillus Subtilis ◽

Spatial Structure ◽

Bacterial Strains ◽

Gram Negative ◽

X Ray ◽

Cyclopropane Derivative

A cyclopropane derivative of limonene, (1 S, 4 S, 6 R)-7,7-dichloro-4-[(1 S)-2,2-dichloro-1-methylcyclopropyl]-1-methylbicyclo [4.1.0] heptane (compound 2), was synthesized and its structure was determined by NMR and X-ray crystallographic methods. In addition, an antimicrobial activity of the compound against Gram-positive ( Staphylococcus aureus, Bacillus subtilis) and Gram-negative ( Escherichia coli, Pseudomonas aeruginosa) bacterial strains was also scrutinized.

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40 % aq. HF catalyzed three component Synthesis of novel indeno[1,2-b][1,8]naphthyridin-6(11H)-one derivatives and their antimicrobial activity

Letters in Organic Chemistry ◽

10.2174/1570178617666200210112843 ◽

2020 ◽

Vol 17 ◽

Author(s):

Srinu Bhoomandla ◽

Phani Raja Kanuparthy ◽

Rambabu Gundla ◽

Ramana Reddy Bobbala

Keyword(s):

Antimicrobial Activity ◽

Bacillus Subtilis ◽

Candida Albicans ◽

Good Yield ◽

Diffusion Method ◽

Subtilis Strain ◽

Bacterial Strains ◽

Gram Positive ◽

Gram Negative ◽

Aryl Aldehyde

: A Three component Synthesis of novel 5-phenyl-2-(thiophen-2-yl)-4-(trifluoromethyl)-5H-indeno [1,2-b] [1,8] naphthyridin-6(11H)-one derivatives (4a-n) were prepared using 6-phenyl/(thiophen-2-yl)-4-(trifluoromethyl)pyridin-2-amine, 1H-indene-1,3(2H)-dione and aryl aldehyde using 40% aq. HF with good yield. All the synthesized compounds were screened against Gram-positive and Gram-negative bacterial strains and different Candida strains by well diffusion method. Compounds 4c, 4f and 4g showed promising activity on Bacillus subtilis strain and compounds 4c and 4g showed promising activity towards Candida albicans starains.

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Antibacterial Properties of Propolis

Molecules ◽

10.3390/molecules24112047 ◽

2019 ◽

Vol 24 (11) ◽

pp. 2047 ◽

Cited By ~ 33

Author(s):

Izabela Przybyłek ◽

Tomasz M. Karpiński

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Antibacterial Properties ◽

Bacterial Strains ◽

Complex Composition ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

The World

Researchers are continuing to discover all the properties of propolis due to its complex composition and associated broad spectrum of activities. This review aims to characterize the latest scientific reports in the field of antibacterial activity of this substance. The results of studies on the influence of propolis on more than 600 bacterial strains were analyzed. The greater activity of propolis against Gram-positive bacteria than Gram-negative was confirmed. Moreover, the antimicrobial activity of propolis from different regions of the world was compared. As a result, high activity of propolis from the Middle East was found in relation to both, Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains. Simultaneously, the lowest activity was demonstrated for propolis samples from Germany, Ireland and Korea.

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SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF SILVER NANOPARTICLES STABILIZED BY CITRATE ANIONS

Proceedings of the Shevchenko Scientific Society. Series Сhemical Sciences ◽

10.37827/ntsh.chem.2020.60.127 ◽

2020 ◽

Vol 2020 (60) ◽

pp. 127-135

Author(s):

Liliya BAZYLYAK ◽

◽

Andriy KYTSYA ◽

Ilona KARPENKO ◽

Olena KARPENKO ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Silver Nanoparticles ◽

Cell Walls ◽

Colloidal Silver ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Vis Spectroscopy

Widespread use of synthetic antimicrobial drugs leads to the development of antibiotic resistance of pathogenic strains of microorganisms. Therefore, today researchers are very interested in drugs based on nanoparticles of metals, in particular silver and copper, which have antibacterial, antifungal and antiviral activity. One of the reasons for the high interest of researchers in AgNPs as an antimicrobial agent is the significantly lower toxicity of AgNPs compared to Ag+ ions. High antibacterial efficiency of silver nano¬particles is achieved due to their developed surface, which provides maximum contact with the environment. In addition, such nanoparticles are quite small and are able to penetrate cell membranes, to affect intracellular processes from within. Therefore, the aim of this work was to obtain concentrated colloidal silver solutions stabilized by citrate anions, which simultaneously provide satisfactory stabilization of colloidal silver solutions and are non-toxic, as well as to investigate the antimicrobial action of synthesized AgNPs. The solution of citrate stabilized silver nanoparticles (AgNPs) have been obtained via the reaction of reduction of silver nitrate by hydrazine in alkaline medium in the presence of sodium citrate. AgNPs were investigated using transmission electron microscopy (TEM) and UV-vis spectroscopy and the particles size and particles size distribution (PSD) were determined. It was observed that obtained AgNPs are mainly spherical shape. It was found that the mean diameter and PSD of AgNPs determined using TEM and UV-vis spectroscopy are close and equal to 14 and 5 nm and 15 and 4 nm respectively. Obtained solution was concentrated by evaporation at 70 C under reduced pressure up to achievement of AgNPs concentration equal to 200 mg/L. On the base of comparison of optical properties of initial silver sol and concentrated solution the minority of agglomeration of AgNPs was statement. At the same time AgNO3 test showed no change of UV-vis spectrum of concentrate that points on the absence of reducing agent in the solution; this fact indicate that hydrazine was eliminated from during the evaporation of initial AgNPs solution and obtained concentrate did not consist the toxic impurities. Antimicrobial activity of obtained citrate stabilised AgNPs against Gram-positive Bacillus subtilis and Gram-negative Escherichia coli bacterium was tested using disk diffusion method. It was found that AgNPs shown significant bactericidal effect even at low (25 mg/L) concentration as well as some higher efficiency against Gram-negative bacterium. There was also a slightly higher antimicrobial activity of the drug against gram-negative bacteria Escherichia coli compared with gram-positive bacteria Bacillus subtilis, due to the different structure of cell walls. In particular, the walls of gram-positive bacteria consist mainly of peptidoglycan (murein), and gram-negative bacteria have cell walls with a layer of peptidoglycan and an outer membrane with a lipopolysaccharide component, which is not present in gram-positive bacteria. Based on the studies, it can be concluded that the proposed method of synthesis of AgNPs is suitable for obtaining highly concentrated silver sols. This method of synthesis is simple in hardware design, scalable, and the resulting colloidal solutions are stable and do not contain harmful impurities. Therefore, due to the high antibacterial activity of citrate-anion-stabilized AgNPs against certain types of gram-positive and gram-negative bacteria, it can be recommended for the manufacture of bactericidal drugs for biomedical purposes.

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Evaluation of Antimicrobial Activity of Cedrela toona Roxb. Fruit Extracts

Journal of Drug Delivery and Therapeutics ◽

10.22270/jddt.v11i1.4540 ◽

2021 ◽

Vol 11 (1) ◽

pp. 108-109

Author(s):

Kinjal H Shah ◽

Piyush M. Patel

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Bacillus Subtilis ◽

Bacterial Species ◽

Plate Method ◽

Gram Positive ◽

Gram Negative ◽

Negative Bacillus ◽

Gram Negative Bacillus

Evaluation of antimicrobial activity was performed by cup-plate method. The test microorganisms used for the antimicrobial activity were four bacterial species (two Gram positive and two Gram negative) – Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeuroginosa,Escherichia coli. The test microorganisms used for the antimicrobial activity were four bacterial species (two Gram +ve and two Gram -ve) Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeuroginosa,Escherichia coli.

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Tetracycline Water Soluble Formulations with Enhanced Antimicrobial Activity

Antibiotics ◽

10.3390/antibiotics9120845 ◽

2020 ◽

Vol 9 (12) ◽

pp. 845

Author(s):

A. Meretoudi ◽

C. N. Banti ◽

P. Siafarika ◽

A. G. Kalampounias ◽

S. K. Hadjikakou

Keyword(s):

Antimicrobial Activity ◽

Water Solubility ◽

Attenuated Total Reflection ◽

Water Soluble ◽

Bacterial Strains ◽

Scanning Calorimetry ◽

Gram Positive ◽

Gram Negative ◽

Vis Spectroscopy

The negligible water solubility of tetracycline (TC), a well-known antibiotic of clinical use, is the major disadvantage for its oral administration. With the aim to improve the water solubility of TC, the micelles of formulae SLS@TC and CTAB@TC (SLS = sodium lauryl sulphate and CTAB = cetrimonium bromide) were synthesized. The micelles SLS@TC and CTAB@TC were characterized by melting point (m.p.), thermogravimetric differential thermal analysis (TG-DTA), differential scanning calorimetry (DTG/DSC), attenuated total reflection spectroscopy (FT-IR-ATR), ultra-violet visible (UV/vis) spectroscopy, proton nucleus magnetic resonance (1H-NMR) spectroscopy, and the ultrasonically-induced biregringence technique. The antimicrobial activity of SLS@TC and CTAB@TC was evaluated, by means of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and inhibition zone (IZ), against the Gram negative bacterial strains Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli) and the Gram positive ones of the genus of Staphylococcus epidermidis (S. epidermidis) and Staphylococcus aureus (S. aureus). Generally, both micelles show better activity than that of TC against the microbial strains tested. Thus, the MIC value of CTAB@TC is 550-fold higher than that of free TC against S. epidermidis. Despite the stronger activity of CTAB@TC than SLS@TC against both Gram negative and Gram positive microbes, SLS@TC is classified as a bactericidal agent (in that it eliminates 99.9% of the microbes), in contrast to CTAB@TC, which is bacteriostatic one (inhibits, but does not kill the organisms). The toxicity of SLS@TC and CTAB@TC was evaluated against human corneal eukaryotic cells (HCECs). Moreover, SLS@TC and CTAB@TC exhibit low in vivo toxicity against Artemia salina, even at concentrations up to threefold higher than those of their MICmax. Therefore, SLS@TC and CTAB@TC can be candidates for the development of new antibiotics.

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Synthesis, Characterization and Antimicrobial Activity of Bis-Acetylferrocene Schiff Base

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.1875 ◽

2011 ◽

Vol 396-398 ◽

pp. 1875-1878 ◽

Cited By ~ 1

Author(s):

Yu Ting Liu ◽

Hai Long Guo ◽

Da Wei Yin

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antimicrobial Activity ◽

Bacillus Subtilis ◽

Salmonella Typhi ◽

Bacterial Strains ◽

Gram Negative ◽

And Staphylococcus Aureus

Three bis-acetylferrocene schiff bases have been synthesized and characterized by IR, 1H NMR, and elemental analysis, the results conformed well with expected structures. The synthesized compounds were screened in vitro for their antimicrobial activity against three Gram-negative (Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi) and two Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacterial strains. The results showed that these compounds are show excellent antimicrobia activities against Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi ,Bacillus subtilis,Staphylococcus aureus.

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Synthesis, characterization and antibacterial evaluation of novel benzothiazole clubbed acetamide derivatives

Research Journal of Chemistry and Environment ◽

10.25303/257rjce15721 ◽

2021 ◽

Vol 25 (7) ◽

pp. 157-160

Author(s):

Vikaskumar Shukla ◽

Jayesh Jadhav ◽

Maharshi Shukla ◽

Jigar Patel ◽

Jyotindra Mahyavanshi ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Bacillus Subtilis ◽

Bacterial Strains ◽

Gram Positive ◽

Gram Negative ◽

Benzothiazole Derivatives ◽

Antibacterial Evaluation ◽

Antibacterial Potential

A novel series of mercapto benzothiazole derivatives clubbed through acetamide linkage was designed and synthesized which was subjected to antibacterial evaluation using gram positive bacterial strains Staphylococcus aureus and Bacillus subtilis and Pseudomonas aeruginosa and Escherichia coli as gram negative strains. Some of the synthesized compounds showed their excellent antibacterial potential.

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Antimicrobial Activity of Iron-Halide Complexes Against Gram-Positive and Gram-Negative Bacteria

10.26434/chemrxiv.11864934.v1 ◽

2020 ◽

Author(s):

Nusrat Abedin ◽

Abdullah Hamed A Alshehri ◽

Ali M A Almughrbi ◽

Olivia Moore ◽

Sheikh Alyza ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Resistance ◽

Extracellular Dna ◽

Antibiofilm Activity ◽

Gram Negative Bacteria ◽

Bacterial Strains ◽

Gram Positive ◽

Gram Negative ◽

Antimicrobial Substances ◽

Mammalian Cell Lines

Antimicrobial resistance (AMR) has become one of the more serious threats to the global health. The emergence of bacteria resistant to antimicrobial substances decreases the potencies of current antibiotics. Consequently, there is an urgent and growing need for the developing of new classes of antibiotics. Three prepared novel iron complexes have a broad-spectrum antimicrobial activity with minimum bactericidal concentration (MBC) values ranging from 3.5 to 10 mM and 3.5 to 40 mM against Gram-positive and Gram-negative bacteria with antimicrobial resistance phenotype, respectively. Time-kill studies and quantification of the extracellular DNA confirmed the bacteriolytic mode of action of the iron-halide compounds. Additionally, the novel complexes showed significant antibiofilm activity against the tested pathogenic bacterial strains at concentrations lower than the MBC. The cytotoxic effect of the complexes on different mammalian cell lines show sub-cytotoxic values at concentrations lower than the minimum bactericidal concentrations.

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Ultrasonic Irradiation: Synthesis, Characterization, and Preliminary Antimicrobial Activity of Novel Series of 4,6-Disubstituted-1,3,5-triazine Containing Hydrazone Derivatives

Journal of Chemistry ◽

10.1155/2016/3464758 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Hessa H. Al-Rasheed ◽

Monirah Al Alshaikh ◽

Jamal M. Khaled ◽

Naiyf S. Alharbi ◽

Ayman El-Faham

Keyword(s):

Antimicrobial Activity ◽

Ultrasonic Irradiation ◽

New Products ◽

Conventional Heating ◽

Pyridine Derivative ◽

Gram Negative Bacteria ◽

Bacterial Strains ◽

Gram Positive ◽

Gram Negative ◽

Antimicrobial And Antifungal Activities

Novel series of 4,6-disubstituted-1,3,5-triazines containing hydrazone derivatives were synthesized employing ultrasonic irradiation and conventional heating. The ultrasonication gave the target products in higher yields and purity in shorter reaction time compared with the conventional method. IR, NMR (H 1 and C 13), elemental analysis, and LC-MS confirmed the structures of the new products. The antimicrobial and antifungal activities were evaluated for all the prepared compounds against some selected Gram-positive and Gram-negative bacterial strains. The results showed that only two compounds 7i (pyridine derivative) and 7k (4-chlorobenzaldehyde derivative) displayed biological activity against some Gram-positive and Gram-negative bacteria, while the rest of the tested compounds did not display any antifungal activity.

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