Synthesis of a Novel, Biocompatible and Bacteriostatic Borosiloxane Composition with Silver Oxide Nanoparticles

Microbial antibiotic resistance is an important global world health problem. Recently, an interest in nanoparticles (NPs) of silver oxides as compounds with antibacterial potential has significantly increased. From a practical point of view, composites of silver oxide NPs and biocompatible material are of interest. A borosiloxane (BS) can be used as one such material. A composite material combining BS and silver oxide NPs has been synthesized. Composites containing BS have adjustable viscoelastic properties. The silver oxide NPs synthesized by laser ablation have a size of ~65 nm (half-width 60 nm) and an elemental composition of Ag2O. The synthesized material exhibits strong bacteriostatic properties against E. coli at a concentration of nanoparticles of silver oxide more than 0.01%. The bacteriostatic effect depends on the silver oxide NPs concentration in the matrix. The BS/silver oxide NPs have no cytotoxic effect on a eukaryotic cell culture when the concentration of nanoparticles of silver oxide is less than 0.1%. The use of the resulting composite based on BS and silver oxide NPs as a reusable dry disinfectant is due to its low toxicity and bacteriostatic activity and its characteristics are not inferior to the medical alloy nitinol.

Download Full-text

Photocatalytic degradation of caffeine and E. coli inactivation using silver oxide nanoparticles obtained by a facile green co-reduction method

Clean Technologies and Environmental Policy ◽

10.1007/s10098-021-02135-7 ◽

2021 ◽

Author(s):

Harshiny Muthukumar ◽

Santosh Kumar Palanirajan ◽

Manoj Kumar Shanmugam ◽

Pugazhendhi Arivalagan ◽

Sathyanarayana N. Gummadi

Keyword(s):

Photocatalytic Degradation ◽

Reduction Method ◽

Silver Oxide ◽

Oxide Nanoparticles ◽

E Coli ◽

Silver Oxide Nanoparticles ◽

Co Reduction

Download Full-text

New Insights into the Degradation Path of Deltamethrin

Molecules ◽

10.3390/molecules26133811 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3811

Author(s):

Federica Aiello ◽

Marcel G. Simons ◽

Jan W. van Velde ◽

Paulo Dani

Keyword(s):

Degradation Products ◽

World Health ◽

Vector Borne Diseases ◽

Insecticidal Efficacy ◽

The Matrix ◽

Low Toxicity ◽

Vector Borne ◽

Health Organization ◽

By Products ◽

Insecticidal Compounds

Pyrethroids are among the insecticidal compounds indicated by the World Health Organization for mitigation of vector-borne diseases. Active deltamethrin (with chiral configuration α-S,1-R-cis) is one of the most effective pyrethroids characterized by low toxicity to humans, and it is currently tested as active ingredient for insecticidal paints. Nevertheless, several degradation processes can occur and affect the insecticidal efficacy in the complex paint matrix. In the present study, a detailed NMR analysis of deltamethrin stability has been carried out under stress conditions, mimicking a water-based insecticidal paint environment. Two novel by-products, having a diastereomeric relationship, were identified and their structure was elucidated by combining NMR, HPLC, GC-MS, and ESI-MS analyses. These compounds are the result from a nucleophilic addition involving deltamethrin and one of its major degradation products, 3-phenoxybenzaldehyde. Given the known toxicity of the aldehyde, this reaction could represent a way to reduce its concentration into the matrix. On the other hand, the toxicology of these compounds towards humans should be addressed, as their presence may adversely affect the performance of deltamethrin-containing products.

Download Full-text

Photocatalytic degradation of caffeine and E. coli inactivation using silver oxide nanoparticles obtained by a facile green co-reduction method

10.21203/rs.3.rs-245921/v1 ◽

2021 ◽

Author(s):

Harshiny Muthukumar ◽

Santosh Kumar Palanirajan ◽

Manoj Kumar Shanmugam ◽

Arivalagan Pugazhendhi ◽

Sathyanarayana N. Gummadi

Keyword(s):

Photocatalytic Degradation ◽

Silver Oxide ◽

Antioxidant Activities ◽

Average Particle Size ◽

Bactericidal Effect ◽

Oxide Nanoparticles ◽

Average Particle ◽

E Coli ◽

Silver Oxide Nanoparticles ◽

Compact Fluorescent Lamp

Abstract In this study, silver oxide nanoparticles (Ag2O-NPs) were synthesized from silver nitrate using green amaranth leaf extract as reducing agent. The degradation of caffeine and inactivation of Escherichia coli by Ag2O-NPs was studied under compact fluorescent lamp illumination irradiation. Apart from that, the antibacterial and antioxidant activities of Ag2O-NPs were also examined. Synthesized Ag2O-NPs were shaped like monodispersed husk, and cubic structured with surface area and average particle size was detected to be 100.21 (m2/g) and 81 nm respectively. Antioxidant efficacy of the Ag2O-NPs was evaluated using 1, 1-diphenyl-2-picrylhydrazyl and 91% inhibition was achieved with 100 µg Ag2O-NPs. Bacteriocidic propensity of Ag2O-NPs was examined against the S. aureus and P. aeruginosa by disc diffusion, minimum inhibitory concentration (MIC), Live and dead assay. It was observed that the NPs have higher bactericidal effect on Gram-negative as compared to Gram-positive bacteria. Up to 96% photocatalytic inactivation of E. coli was achieved using 30 µg/mL of NPs, Photocatalytic degradation of caffeine (50 ppm initial concentration) was observed to be 99% at pH 9 in 15 h using 50 mg/L of Ag2O NPs. These results indicate that Ag2O NPs can be employed in environmental applications like harmful bacteria inactivation and organic pollutants degradation.

Download Full-text

Flouride and Nitrate Status of Some Ground Waters in Chittor District of Rajasthan State (India)

International Journal of Emerging Research in Management and Technology ◽

10.23956/ijermt.v6i9.95 ◽

2018 ◽

Vol 6 (9) ◽

pp. 119

Author(s):

Trapti Sharma ◽

R. P. Nagar ◽

R. C. Gaur ◽

Pooja Gupta ◽

Charanjit Kaur

Keyword(s):

Point Of View ◽

World Health ◽

Indian Council ◽

Standard Methods ◽

Ground Waters ◽

Drinking Waters ◽

Health Organization ◽

Research World ◽

Drinking Purpose

In Rajasthan state the ground waters of some areas like Ramganj-mandi, Morak, Barmer, Jaisalmer, Chittor and Udaipur etc. are susceptible from drinking point of view.To test the quality of groundwater in Chittor district 14, ground water samples were collected from various places and analyzed for pH, E.C., Fluoride and Nitrate parameters by standard methods (A.P.H. A., Washington, USA, 1995). The study revealed that none of the ground waters was found suitable completely from drinking point of view. Some are having electrical conductivity > 1.4 dS/m, some are having pH >8.5, some area having fluoride >1.5 ppm and some are having nitrate>45 ppm. These are the limits of various parameters permitted by various International authorities like Bureau of Indian Standard, Indian Council of Medical Research,world health Organization etc. for drinking waters. So, it is recommended to the residents of above areas to use water for drinking purpose only after reverse osmosis or adopting suitable method of removing excess of Fluoride and Nitrate for drinking water to avoid unwanted pathogenic diseases harmful for human health.

Download Full-text

Comparison of the ColiPlate™ Kit with Two Common E. coli Enumeration Methods for Water

Water ◽

10.3390/w13131804 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1804

Author(s):

Cassi J. Gibson ◽

Abraham K. Maritim ◽

Jason W. Marion

Keyword(s):

High Risk ◽

Natural Water ◽

Membrane Filtration ◽

Fecal Contamination ◽

Reference Method ◽

World Health ◽

Risk Levels ◽

E Coli ◽

Field Samples ◽

Very High

Quantitatively assessing fecal indicator bacteria in drinking water from limited resource settings (e.g., disasters, remote areas) can inform public health strategies for reducing waterborne illnesses. This study aimed to compare two common approaches for quantifying Escherichia coli (E. coli) density in natural water versus the ColiPlate™ kit approach. For comparing methods, 41 field samples from natural water sources in Kentucky (USA) were collected. E. coli densities were then determined by (1) membrane filtration in conjunction with modified membrane-thermotolerant E. coli (mTEC) agar, (2) Idexx Quanti-Tray® 2000 with the Colilert® substrate, and (3) the Bluewater Biosciences ColiPlate kit. Significant correlations were observed between E. coli density data for all three methods (p < 0.001). Paired t-test results showed no difference in E. coli densities determined by all the methods (p > 0.05). Upon assigning modified mTEC as the reference method for determining the World Health Organization-assigned “very high-risk” levels of fecal contamination (> 100 E. coli CFU/100 mL), both ColiPlate and Colilert exhibited excellent discrimination for screening very high-risk levels according to the area under the receiver operating characteristic curve (~89%). These data suggest ColiPlate continues to be an effective monitoring tool for quantifying E. coli density and characterizing fecal contamination risks from water.

Download Full-text

A novel bis(pyrazolyl)methane compound as a potential agent against Gram-positive bacteria

Scientific Reports ◽

10.1038/s41598-021-95609-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Pedro Seguí ◽

John J. Aguilera-Correa ◽

Elena Domínguez-Jurado ◽

Christian M. Sánchez-López ◽

Ramón Pérez-Tanoira ◽

...

Keyword(s):

Antibacterial Activity ◽

Inhibitory Effect ◽

Eukaryotic Cell ◽

Liver Carcinoma ◽

Gram Positive ◽

Minimal Inhibitory Concentrations ◽

E Coli ◽

Gram Positive Bacteria ◽

Therapeutic Compounds ◽

Toxic Concentrations

AbstractThis study was designed to propose alternative therapeutic compounds to fight against bacterial pathogens. Thus, a library of nitrogen-based compounds bis(triazolyl)methane (1T–7T) and bis(pyrazolyl)methane (1P–11P) was synthesised following previously reported methodologies and their antibacterial activity was tested using the collection strains of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa. Moreover, the novel compound 2P was fully characterized by IR, UV–Vis and NMR spectroscopy. To evaluate antibacterial activity, minimal inhibitory concentrations (MICs), minimal bactericidal concentrations (MBCs), minimum biofilm inhibitory concentrations (MBICs), and minimum biofilm eradication concentrations (MBECs) assays were carried out at different concentrations (2–2000 µg/mL). The MTT assay and Resazurin viability assays were performed in both human liver carcinoma HepG2 and human colorectal adenocarcinoma Caco-2 cell lines at 48 h. Of all the synthesised compounds, 2P had an inhibitory effect on Gram-positive strains, especially against S. aureus. The MIC and MBC of 2P were 62.5 and 2000 µg/mL against S. aureus, and 250 and 2000 µg/mL against E. faecalis, respectively. However, these values were > 2000 µg/mL against E. coli and P. aeruginosa. In addition, the MBICs and MBECs of 2P against S. aureus were 125 and > 2000 µg/mL, respectively, whereas these values were > 2000 µg/mL against E. faecalis, E. coli, and P. aeruginosa. On the other hand, concentrations up to 250 µg/mL of 2P were non-toxic doses for eukaryotic cell cultures. Thus, according to the obtained results, the 2P nitrogen-based compound showed a promising anti-Gram-positive effect (especially against S. aureus) both on planktonic state and biofilm, at non-toxic concentrations.

Download Full-text

Ovalbumin mediated eco-friendly synthesis of silver oxide nanoparticles and their antibacterial and antifungal studies

Materials Today Proceedings ◽

10.1016/j.matpr.2021.04.403 ◽

2021 ◽

Author(s):

Indresh Kumar ◽

Bushra Yaseen ◽

Chinky Gangwar ◽

Rupal Yadav ◽

Sheo K. Mishra ◽

...

Keyword(s):

Silver Oxide ◽

Oxide Nanoparticles ◽

Silver Oxide Nanoparticles ◽

Antibacterial And Antifungal

Download Full-text

Secretion of Anti-Plasmodium Effector Proteins from a Natural Pantoea agglomerans Isolate by Using PelB and HlyA Secretion Signals

Applied and Environmental Microbiology ◽

10.1128/aem.00514-11 ◽

2011 ◽

Vol 77 (13) ◽

pp. 4669-4675 ◽

Cited By ~ 43

Author(s):

Dawn C. Bisi ◽

David J. Lampe

Keyword(s):

Control Strategies ◽

Pectate Lyase ◽

Erwinia Carotovora ◽

Individual Characteristics ◽

Pantoea Agglomerans ◽

Effector Proteins ◽

World Health ◽

Content Type ◽

E Coli ◽

The Individual

ABSTRACTThe insect-vectored disease malaria is a major world health problem. New control strategies are needed to supplement the current use of insecticides and medications. A genetic approach can be used to inhibit development of malaria parasites (Plasmodiumspp.) in the mosquito host. We hypothesized thatPantoea agglomerans, a bacterial symbiont ofAnophelesmosquitoes, could be engineered to express and secrete anti-Plasmodiumeffector proteins, a strategy termed paratransgenesis. To this end, plasmids that include thepelBorhlyAsecretion signals from the genes of related species (pectate lyase fromErwinia carotovoraand hemolysin A fromEscherichia coli, respectively) were created and tested for their efficacy in secreting known anti-Plasmodiumeffector proteins (SM1, anti-Pbs21, and PLA2) inP. agglomeransandE. coli.P. agglomeranssuccessfully secreted HlyA fusions of anti-Pbs21 and PLA2, and these strains are under evaluation for anti-Plasmodiumactivity in infected mosquitoes. Varied expression and/or secretion of the effector proteins was observed, suggesting that the individual characteristics of a particular effector may require empirical testing of several secretion signals. Importantly, those strains that secreted efficiently grew as well as wild-type strains under laboratory conditions and, thus, may be expected to be competitive with the native microbiota in the environment of the mosquito midgut.

Download Full-text

Cloning of Salmonella enterica Serovar Enteritidis Fimbrial Protein SefA as a Surface Protein in Escherichia coli Confers the Ability To Attach to Eukaryotic Cell Lines

Applied and Environmental Microbiology ◽

10.1128/aem.00639-09 ◽

2009 ◽

Vol 75 (20) ◽

pp. 6622-6625 ◽

Cited By ~ 6

Author(s):

Douglas L. Rank ◽

Mahdi A. Saeed ◽

Peter M. Muriana

Keyword(s):

Escherichia Coli ◽

Salmonella Enterica ◽

Expression Vector ◽

Surface Protein ◽

Surface Expression ◽

Eukaryotic Cell ◽

Salmonella Enterica Serovar Enteritidis ◽

Western Blot Assay ◽

E Coli ◽

Fimbrial Protein

ABSTRACT The gene for the Salmonella enterica serovar Enteritidis fimbrial protein SefA was cloned into an Escherichia coli surface expression vector and confirmed by Western blot assay. E. coli clones expressing SefA attached to avian ovary granulosa cells and HEp-2 cells, providing evidence for the involvement of SefA in the ability of Salmonella to attach to eukaryotic cells.

Download Full-text