Thermoresponsive Poly(N-Isopropylacrylamide-co-Dimethylaminoethyl Methacrylate) Microgel Aqueous Dispersions with Potential Antimicrobial Properties

The work herein describes the preparation of thermoresponsive microgels with potential antimicrobial properties. Most of the work performed so far regarding microgels with antimicrobial activity, deals with the ability of microgels to carry and release antibiotics or antimicrobial agents (antimicrobial peptides). The originality of this work lies in the possibility of developing intrinsic antimicrobial microgels by copolymerization of the well-known thermoresponsive monomer, N-isopropylacrylamide (NIPAM) with dimethylaminoethyl methacrylate (DMAEMA), a water-soluble monomer, to form microgels via precipitation polymerization (radical polymerization). Due to the presence of a tertiary amine in the DMAEMA comonomer, microgels can be modified by N-alkylation reaction with methyl and butyl iodide. This quaternization confers positive charges to the microgel surfaces and thus the potential antimicrobial activity. The effect of DMAEMA content and its quaternization with both, methyl and butyl iodide is evaluated in terms of thermal and surface charge properties, as well as in the microgel size and viscoelastic behavior. Finally, a preliminary study of the antimicrobial activity against different microorganisms is also performed in terms of minimum inhibitory concentration (MIC). From this study we determined that in contrast with butylated microgels, methylated ones show potential antimicrobial activity and good physical properties besides of maintaining microgel thermo-responsiveness.

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An In Vitro Study on the Antimicrobial Properties of Essential Oil Modified Resin Composite against Oral Pathogens

Materials ◽

10.3390/ma13194383 ◽

2020 ◽

Vol 13 (19) ◽

pp. 4383

Author(s):

Barbara Lapinska ◽

Aleksandra Szram ◽

Beata Zarzycka ◽

Janina Grzegorczyk ◽

Louis Hardan ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antibacterial Activity ◽

Antifungal Activity ◽

Antimicrobial Agents ◽

Resin Composite ◽

Antimicrobial Properties ◽

In Vitro Study ◽

Diffusion Method ◽

Oral Pathogens

Modifying the composition of dental restorative materials with antimicrobial agents might induce their antibacterial potential against cariogenic bacteria, e.g., S.mutans and L.acidophilus, as well as antifungal effect on C.albicans that are major oral pathogens. Essential oils (EOs) are widely known for antimicrobial activity and are successfully used in dental industry. The study aimed at evaluating antibacterial and antifungal activity of EOs and composite resin material (CR) modified with EO against oral pathogens. Ten EOs (i.e., anise, cinnamon, citronella, clove, geranium, lavender, limette, mint, rosemary thyme) were tested using agar diffusion method. Cinnamon and thyme EOs showed significantly highest antibacterial activity against S.mutans and L.acidophilus among all tested EOs. Anise and limette EOs showed no antibacterial activity against S.mutans. All tested EOs exhibited antifungal activity against C.albicans, whereas cinnamon EO showed significantly highest and limette EO significantly lowest activity. Next, 1, 2 or 5 µL of cinnamon EO was introduced into 2 g of CR and microbiologically tested. The modified CR showed higher antimicrobial activity in comparison to unmodified one. CR containing 2 µL of EO showed the best antimicrobial properties against S.mutans and C.albicans, while CR modified with 1 µL of EO showed the best antimicrobial properties against L.acidophilus.

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SYNTHESIS AND STRUCTURAL ELUCIDATION OF AMINO ACETYLENIC AND THIOCARBAMATES DERIVATIVES FOR 2-MERCAPTOBENZOTHIAZOLE AS ANTIMICROBIAL AGENTS

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i2.15760 ◽

2017 ◽

Vol 9 (2) ◽

pp. 192

Author(s):

Aseel Alsarahni ◽

Zuhair Muhi Eldeen ◽

Elham Al-kaissi ◽

Ibrahim Al- Adham ◽

Najah Al-muhtaseb

Keyword(s):

Antimicrobial Activity ◽

Elemental Analysis ◽

Antimicrobial Agents ◽

Diffusion Method ◽

Benzothiazole Derivatives ◽

H Nmr ◽

Ft Ir ◽

Potential Antimicrobial Activity ◽

C Nmr

Objective: To design and synthesize amino acetylenic and thiocarbonate of 2-mercapto-1,3-benthiazoles as potential antimicrobial agents.Methods: A new series of 2-{[4-(t-amino-1-yl) but-2-yn-1-yl] sulfanyl}-1,3-benzothiazole derivatives (AZ1-AZ6), and S-1,3-benzothiazol-2-yl-O-alkyl carbonothioate derivatives were synthesised, with the aim that the target compounds show new and potential antimicrobial activity. The elemental analysis was indicated by the EuroEA elemental analyzer, and biological characterization was via IR, 1H-NMR, [13]C-NMR, DSC were determined with the aid of Bruker FT-IR and Varian 300 MHz spectrometer using DMSO-d6 as a solvent. In vitro antimicrobial activity, evaluation was done for the synthesised compounds, by agar diffusion method and broth dilution test. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined. Results: The IR, 1H-NMR, 13C-NMR, DSC and elemental analysis were consistent with the assigned structures. Compound of 2-{[4-(4-methylpiperazin-1-yl)but-2-yn-1-yl] sulfanyl}-1,3-benzothiazole (AZ1), 2-{[4-(2-methylpiperidin-1-yl)but-2-yn-1-yl]sulfanyl}-1,3-benzothiazole (AZ2), 2-{[4-(piperidin-1-yl) but-2-yn-1-yl]sulfanyl}-1, 3-benzothiazole (AZ6), S-1,3-benzothiazol-2-yl-O-ethyl carbonothioate (AZ7), and S-1,3-benzothiazol-2-yl-O-(2-methylpropyl) carbonothioate (AZ9) showed the highest antimicrobial activity against Pseudomonas aeruginosa (P. aeruginosa), AZ-9 demonstrated the highest antifungal activity against Candida albicans (C. albicans), with MIC of 31.25 µg/ml.Conclusion: These promising results promoted our interest to investigate other structural analogues for their antimicrobial activity further.

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Quaternary Salts of Chitosan: History, Antimicrobial Features, and Prospects

International Journal of Carbohydrate Chemistry ◽

10.1155/2011/312539 ◽

2011 ◽

Vol 2011 ◽

pp. 1-12 ◽

Cited By ~ 25

Author(s):

Douglas de Britto ◽

Rejane Celi Goy ◽

Sergio Paulo Campana Filho ◽

Odilio B. G. Assis

Keyword(s):

Physical Chemistry ◽

Antimicrobial Activity ◽

Drug Delivery Systems ◽

Antimicrobial Properties ◽

Water Soluble ◽

Chemical Characteristics ◽

Packaging Materials ◽

Inhibitory Effects ◽

Quaternary Salts ◽

Derivatives Of

Recently, increasing attention has been paid to water-soluble derivatives of chitosan at its applications. The chemical characteristics and the antimicrobial properties of these salts can play significant role in pharmacological and food areas mainly as carriers for drug delivery systems and as antimicrobial packaging materials. In the current paper, a historical sequence of the main preparative methods, physical chemistry aspects, and antimicrobial activity of chitosan quaternized derivatives are presented and briefly discussed. In general, the results indicated that the quaternary derivatives had better inhibitory effects than the unmodified chitosan.

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Phytochemical Screening of Quaking Aspen (Populus tremuloides) Extracts by UPLC-QTOF-MS and Evaluation of their Antimicrobial Activity

Molecules ◽

10.3390/molecules23071739 ◽

2018 ◽

Vol 23 (7) ◽

pp. 1739 ◽

Cited By ~ 4

Author(s):

Annabelle St-Pierre ◽

Dorian Blondeau ◽

André Lajeunesse ◽

Julien Bley ◽

Nathalie Bourdeau ◽

...

Keyword(s):

Antimicrobial Activity ◽

Populus Tremuloides ◽

Antimicrobial Agents ◽

Methanol Extract ◽

Antimicrobial Properties ◽

Water Extract ◽

Pathogen Resistance ◽

Quaking Aspen ◽

Antimicrobial Compounds ◽

Minimal Inhibition Concentration

The continual emergence of pathogen resistance is a recurring challenge and pushes for the development of antimicrobial compounds. Here, we investigated compounds from quaking aspen trees (Populus tremuloides) as potential antimicrobial agents. Several extractions using different solvents were realized, and corresponding antimicrobial activity was tested against eight microorganisms. Results revealed that polar extraction solvents including water, ethanol and methanol gave the best extraction yields (>15.07%). Minimal inhibition concentration (MIC) and minimal bactericidal/fungicidal concentration (MBC/MFC) demonstrated that water extracts had the best antimicrobial activity by a weak to moderate inhibition of growth of all eight tested microorganisms in addition to having a bactericidal effect on three of them. The quaking aspen methanol extract also displayed antimicrobial activity but to a lower level than the water extract. Ultra-performance liquid chromatography quadrupole time-of flight mass spectrometry (UPLC-QTOF-MS) analysis led to the identification of 92 compounds, mainly polyphenols in both extracts, with 22 molecules previously known for their antimicrobial properties. According to the relative abundance, 4-hydroxybenzaldehyde (5.44% in methanol extract) and kaempferol (5.03% in water extract) were the most abundant antimicrobial compounds. Among antimicrobial molecules identified, nine were from the flavonoid family. The results of our study demonstrate the interest of using quaking aspen as source of antimicrobial compounds.

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Biosynthesis and application of silver nano-biotics for enhancing the antimicrobial activity of glass-ionomer cement against studied microorganisms and its effect on compressive strength

10.21203/rs.3.rs-35758/v2 ◽

2020 ◽

Author(s):

Enas Tawfik Enan ◽

Amal A. Ashour ◽

Sakeenabi Basha ◽

Nayef H. Felemban ◽

sanaa M. F. gad El-Rab

Keyword(s):

Antimicrobial Activity ◽

Compressive Strength ◽

Antimicrobial Agents ◽

Glass Ionomer Cement ◽

Antimicrobial Properties ◽

Visible Spectrum ◽

Test System ◽

Glass Ionomer ◽

Group D ◽

Ionomer Cement

Abstract Background. The development of dental caries is associated with various microorganisms and secondary caries formation is the main cause of restorations failure. The advise for restorative dental materials that have antimicrobial properties has stimulated the introduction of materials containing different antibacterial agents.Objectives: Present study has been designed to synthesize silver nanoparticles (AgNPs) and incorporate AgNPs and amoxicillin into glass ionomer cement (GIC) to synergize its effect on oral microbes. The effect of the added antimicrobial agents on compressive strength (CS) of GIC was also evaluated.Material and methods: Biosynthesis of AgNPs were done using Cupressus macrocarpa extract and AgNPs were charectatrized. A total of 120 disc-shaped specimens were prepared and classified into 4 main groups where Group A include conventional GIC, Groups B and C include GIC with AgNPs or Amoxicillin, respectively, while Group D included GIC with both AgNPs and Amoxicillin. Each group was tested for the antimicrobial activity against both Streptococcus mutans (S. mutans) and Staphylococcus aureus (S. aureus). The distribution of biofilm was examined via scanning electron microscope. The CS of the tested material was measured using a Material Test System(MTS).Results: UV-Visible spectrum showed a peak of 429 nm. TEM, XRD pattern and FTIR analysis confirmed the formation of AgNPs with spherical to oblong polydispersed particles of diameter in the range of 13.5-25.8 nm. The maximum inhibitory zone was recorded for group D against both tested bacteria with a mean of 29 mm at first 24-hour period to 15 mm at three weeks and showed antimicrobial rate 92.2% and 92.56%, against both strains, respectively. Additionally, group D disintegrated the structure of S. aureus biofilm and even kill bacteria in the biofilms. Addition of AgNPs and Amoxicillin caused an insignificant effect on CS of GIC.Conclusion: TheAgNPs showed a synergistic effect in combination with amoxicillin and GIC dental restorative material against studied microorganisms. The agents can be safely added with minimal effect on mechanical properties of the original cement.

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Evaluation of antimicrobial activity of three important medicinal plants of South India

Annals of Plant Sciences ◽

10.21746/aps.2018.8.1.1 ◽

2019 ◽

Vol 8 (1) ◽

pp. 3484

Author(s):

Gopalakrishnaiah B. ◽

Aniel Kumar O.

Keyword(s):

Antimicrobial Activity ◽

Medicinal Plants ◽

Pathogenic Bacteria ◽

Antimicrobial Agents ◽

Antimicrobial Properties ◽

Development Program ◽

Antimicrobial Effect ◽

Trichophyton Mentagrophytes ◽

Crude Extracts ◽

The World

India is found to be a country with rich biodiversity and enormous treasure of herbal plants and consequently called as medicinal garden of the world. Plants are the richest source of natural antimicrobial agents. In recent years drug resistance to human pathogenic bacteria has been commonly reported from all over the world. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infectious diseases; one approach is to screen local medicinal plants for possible antimicrobial properties. The present study was designed to evaluate the antimicrobial efficacy of hexane, chloroform and methanol crude extracts of the leaves of three important medicinal plants viz., Biophytum sensitivum (L.) DC, Bougainvillea spectabilis L. and Caesalpinia bonducella (L.) Fleming, collected from in and around Visakhapatnam District. The antimicrobial activity of the crude extracts was tested against three Gram Positive bacteria (Bacillus subtilis MTCC 441, Enterococcus faecalis MTCC 439, Staphylococcus aureus MTCC 737), Three Gram Negative bacteria (Escherichia coli MTCC 443, Proteus vulgaris MTCC 426 and Pseudomonas aeruginosa MTCC 1688) and three Fungal strains (Candida albicans MTCC 227, Epidermophyton floccosum MTCC 613 and Trichophyton mentagrophytes MTCC 7687) using agar well diffusion assay. Our results demonstrated that methanol extracts of these plants leaves have concentration dependent antibacterial activity against some of the tested organisms. Further studies should be undertaken to elucidate the exact mechanism of action of antimicrobial effect to identify the active ingredients which can be used for drug development program.

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Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.11.129 ◽

2020 ◽

Vol 11 ◽

pp. 1450-1469

Author(s):

Matías Guerrero Correa ◽

Fernanda B Martínez ◽

Cristian Patiño Vidal ◽

Camilo Streitt ◽

Juan Escrig ◽

...

Keyword(s):

Antimicrobial Activity ◽

Food Packaging ◽

Antimicrobial Agents ◽

Cell Damage ◽

Metal Oxide Nanoparticles ◽

High Surface ◽

Antimicrobial Properties ◽

Antimicrobial Action ◽

Oxide Nanoparticles ◽

Synthesis Methods

The investigation of novel nanoparticles with antimicrobial activity has grown in recent years due to the increased incidence of nosocomial infections occurring during hospitalization and food poisoning derived from foodborne pathogens. Antimicrobial agents are necessary in various fields in which biological contamination occurs. For example, in food packaging they are used to control food contamination by microbes, in the medical field the microbial agents are important for reducing the risk of contamination in invasive and routine interventions, and in the textile industry, they can limit the growth of microorganisms due to sweat. The combination of nanotechnology with materials that have an intrinsic antimicrobial activity can result in the development of novel antimicrobial substances. Specifically, metal-based nanoparticles have attracted much interest due to their broad effectiveness against pathogenic microorganisms due to their high surface area and high reactivity. The aim of this review was to explore the state-of-the-art in metal-based nanoparticles, focusing on their synthesis methods, types, and their antimicrobial action. Different techniques used to synthesize metal-based nanoparticles were discussed, including chemical and physical methods and “green synthesis” methods that are free of chemical agents. Although the most studied nanoparticles with antimicrobial properties are metallic or metal-oxide nanoparticles, other types of nanoparticles, such as superparamagnetic iron-oxide nanoparticles and silica-releasing systems also exhibit antimicrobial properties. Finally, since the quantification and understanding of the antimicrobial action of metal-based nanoparticles are key topics, several methods for evaluating in vitro antimicrobial activity and the most common antimicrobial mechanisms (e.g., cell damage and changes in the expression of metabolic genes) were discussed in this review.

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The Antimicrobial Activity of Cannabinoids

Antibiotics ◽

10.3390/antibiotics9070406 ◽

2020 ◽

Vol 9 (7) ◽

pp. 406

Author(s):

John A. Karas ◽

Labell J. M. Wong ◽

Olivia K. A. Paulin ◽

Amna C. Mazeh ◽

Maytham H. Hussein ◽

...

Keyword(s):

Antimicrobial Activity ◽

Natural Products ◽

Antimicrobial Agents ◽

Cannabis Sativa ◽

Antimicrobial Properties ◽

Herbaceous Plant ◽

Structure Activity Relationships ◽

Modes Of Action ◽

Structure Activity ◽

Rapid Emergence

A post-antibiotic world is fast becoming a reality, given the rapid emergence of pathogens that are resistant to current drugs. Therefore, there is an urgent need to discover new classes of potent antimicrobial agents with novel modes of action. Cannabis sativa is an herbaceous plant that has been used for millennia for medicinal and recreational purposes. Its bioactivity is largely due to a class of compounds known as cannabinoids. Recently, these natural products and their analogs have been screened for their antimicrobial properties, in the quest to discover new anti-infective agents. This paper seeks to review the research to date on cannabinoids in this context, including an analysis of structure–activity relationships. It is hoped that it will stimulate further interest in this important issue.

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Anthocyanins as Antimicrobial Agents of Natural Plant Origin

Natural Product Communications ◽

10.1177/1934578x1100600136 ◽

2011 ◽

Vol 6 (1) ◽

pp. 1934578X1100600 ◽

Cited By ~ 27

Author(s):

Agnieszka Cisowska ◽

Dorota Wojnicz ◽

Andrzej B. Hendrich

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Agents ◽

Biological Effects ◽

Antimicrobial Properties ◽

Antimicrobial Effect ◽

Pharmaceutical Products ◽

Fresh Fruit ◽

Anthocyanin Content ◽

Human Pathogens ◽

Food Ingredients

Anthocyanins are particularly abundant in different fruits, especially in berries. The beneficial effects of these compounds for human health have been known from at least the 16th century. Despite the great number of papers devoted to the different biological effects exerted by anthocyanins only a limited number of studies is focused on the antimicrobial activity of these compounds. Anthocyanin content of berry fruits varies from 7.5 mg/100 mg fresh fruit in redcurrant ( Ribes rubum) up to 460 mg/100 g fresh fruit in chokeberry ( Aronia melanocarpa). After consumption, anthocyanins are intensively metabolized, mainly in the intestines and liver. Glucorination, methylation and sulfation are the most typical metabolic reactions. Antimicrobial activity of crude extracts of plant phenolic compounds against human pathogens has been intensively studied to characterize and develop new healthy food ingredients as well as medical and pharmaceutical products. However, there is very little information available about the antimicrobial activity of the pure anthocyanins. In the last part of this review we present the collection of papers describing the anthocyanin profiles of different fruits (mainly berries) and the antimicrobial properties of the identified compounds. Generally, anthocyanins are active against different microbes, however Gram-positive bacteria usually are more susceptible to the anthocyanin action than Gram-negative ones. Mechanisms underlying anthocyanin activity include both membrane and intracellular interactions of these compounds. Antimicrobial activity of berries and other anthocyanin-containing fruits is likely to be caused by multiple mechanisms and synergies because they contain various compounds including anthocyanins, weak organic acids, phenolic acids, and their mixtures of different chemical forms. Therefore, the antimicrobial effect of chemically complex compounds has to be critically analyzed.

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Antimicrobial Activity of Human Fetal Membranes: From Biological Function to Clinical Use

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.691522 ◽

2021 ◽

Vol 9 ◽

Author(s):

Taja Železnik Ramuta ◽

Tina Šket ◽

Marjanca Starčič Erjavec ◽

Mateja Erdani Kreft

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Agents ◽

Antimicrobial Properties ◽

Basic Knowledge ◽

Fetal Membranes ◽

Human Amniotic Membrane ◽

Future Studies ◽

Microbial Infections ◽

Chorionic Membrane

The fetal membranes provide a supportive environment for the growing embryo and later fetus. Due to their versatile properties, the use of fetal membranes in tissue engineering and regenerative medicine is increasing in recent years. Moreover, as microbial infections present a crucial complication in various treatments, their antimicrobial properties are gaining more attention. The antimicrobial peptides (AMPs) are secreted by cells from various perinatal derivatives, including human amnio-chorionic membrane (hACM), human amniotic membrane (hAM), and human chorionic membrane (hCM). By exhibiting antibacterial, antifungal, antiviral, and antiprotozoal activities and immunomodulatory activities, they contribute to ensuring a healthy pregnancy and preventing complications. Several research groups investigated the antimicrobial properties of hACM, hAM, and hCM and their derivatives. These studies advanced basic knowledge of antimicrobial properties of perinatal derivatives and also provided an important insight into the potential of utilizing their antimicrobial properties in a clinical setting. After surveying the studies presenting assays on antimicrobial activity of hACM, hAM, and hCM, we identified several considerations to be taken into account when planning future studies and eventual translation of fetal membranes and their derivatives as antimicrobial agents from bench to bedside. Namely, (1) the standardization of hACM, hAM, and hCM preparation to guarantee rigorous antimicrobial activity, (2) standardization of the antimicrobial susceptibility testing methods to enable comparison of results between various studies, (3) investigation of the antimicrobial properties of fetal membranes and their derivatives in the in vivo setting, and (4) designation of donor criteria that enable the optimal donor selection. By taking these considerations into account, future studies will provide crucial information that will enable reaching the optimal treatment outcomes using the fetal membranes and their derivatives as antimicrobial agents.

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