Structure Modification of an Active Azo-Compound as a Route to New Antimicrobial Compounds

Some novel (phenyl-diazenyl)phenols (3a–g) were designed and synthesized to be evaluated for their antimicrobial activity. A previously synthesized molecule, active against bacteria and fungi, was used as lead for modifications and optimization of the structure, by introduction/removal or displacement of hydroxyl groups on the azobenzene rings. The aim of this work was to evaluate the consequent changes of the antimicrobial activity and to validate the hypothesis that, for these compounds, a plausible mechanism could involve an interaction with protein receptors, rather than an interaction with membrane. All newly synthesized compounds were analyzed by 1H nuclear magnetic resonance (NMR), DSC thermal analysis and UV-Vis spectroscopy. The in vitro minimal inhibitory concentrations (MIC) of each compound was determined against Gram-positive and Gram-negative bacteria and Candida albicans. Compounds 3b and 3g showed the highest activity against S. aureus and C. albicans, with remarkable MIC values of 10 µg/mL and 3 µg/mL, respectively. Structure- activity relationship studies were capable to rationalize the effect of different substitutions on the phenyl ring of the azobenzene on antimicrobial activity.

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Antimicrobial Activity and DNA/BSA Binding Affinity of Polynuclear Silver(I) Complexes with 1,2-Bis(4-pyridyl)ethane/ethene as Bridging Ligands

Bioinorganic Chemistry and Applications ◽

10.1155/2020/3812050 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Sonja Ž. Đurić ◽

Sandra Vojnovic ◽

Tina P. Andrejević ◽

Nevena Lj Stevanović ◽

Nada D. Savić ◽

...

Keyword(s):

Antimicrobial Activity ◽

Therapeutic Potential ◽

Fibroblast Cell ◽

Bacterial Strains ◽

Human Lung Fibroblast ◽

Gram Negative ◽

Minimal Inhibitory Concentrations ◽

Lung Fibroblast Cell Line ◽

Bacteria And Fungi

1,2-Bis(4-pyridyl)ethane (bpa) and 1,2-bis(4-pyridyl)ethene (bpe) were used for the synthesis of polynuclear silver(I) complexes, {[Ag(bpa)]NO3}n (1), {[Ag(bpa)2]CF3SO3.H2O}n (2) and {[Ag(bpe)]CF3SO3}n (3). In complexes 1–3, the corresponding nitrogen-containing heterocycle acts as a bridging ligand between two Ag(I) ions. In vitro antimicrobial activity of these complexes, along with the ligands used for their synthesis, was evaluated against the broad panel of Gram-positive and Gram-negative bacteria and fungi. The silver(I) complexes 1–3 showed selectivity towards Candida spp. and Gram-negative Escherichia coli in comparison to the other investigated bacterial strains, effectively inhibiting the growth of four different Candida species with minimal inhibitory concentrations (MICs) between 2.5 and 25 μg/mL and the growth of E. coli, with MIC value being 12.5 μg/mL. Importantly, complex 2 significantly reduced C. albicans filamentation, an essential process for its pathogenesis. Antiproliferative effect on the normal human lung fibroblast cell line MRC-5 was also evaluated with the aim of determining the therapeutic potential of the complexes 1–3. The interactions of these complexes with calf thymus DNA (ctDNA) and bovine serum albumin (BSA) were studied to evaluate their binding activities towards these biomolecules for possible insights on their mode of action.

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Stereospecific ligands and their complexes, Part VIII: Antimicrobial activity of palladium(II) complexes with 0,0'-dialkyl esters of (S,S)-ethylenediamine-N,N'-di-2-(4-methyl)-pentanoic acid

Hemijska industrija ◽

10.2298/hemind110928096i ◽

2012 ◽

Vol 66 (3) ◽

pp. 349-355 ◽

Cited By ~ 4

Author(s):

Dragoslav Ilic ◽

Jelena Vujic ◽

Ivana Radojevic ◽

Olgica Stefanovic ◽

Ljiljana Comic ◽

...

Keyword(s):

Antimicrobial Activity ◽

Minimum Inhibitory Concentration ◽

General Formula ◽

Inhibitory Concentration ◽

Pentanoic Acid ◽

In Vitro Antimicrobial Activity ◽

Microdilution Method ◽

Vis Spectroscopy ◽

Bacteria And Fungi

Palladium(II) complexes (1-4) of general formula [PdCl2(R2-S,S-eddp)] with bidentate N,N?-ligands, O,O'-dialkyl esters (R = ethyl, n-propyl, n-butyl and n-pentyl), of (S,S)-ethylenediamine-N,N?-di-2-(4-methyl)pentanoic acid (S,S-eddp) were prepared and characterized by microanalysis, infrared and UV/VIS spectroscopy. The ligands and its complexes were tested for their in vitro antimicrobial activity against 15 species of bacteria and fungi. Testing is performed by the microdilution method, with the minimum inhibitory concentration (MIC) and the minimum microbicidal concentration (MMC) being determined. The MIC values were in range from 4.9 ?g cm-3 to > 5000 ?g cm-3 while MMC values ranged from 78 ?g cm-3 to > 5000 ?g cm-3. Palladium(II) complexes [PdCl2(Ln)] (n = 1-4) have statistically significant higher activity than the corresponding ligands. The complex 4 displayed the strongest activity among all tested compounds.

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Screening of Antimicrobial Activity and Cytotoxic Effects of Two Cladonia Species

Zeitschrift für Naturforschung C ◽

10.1515/znc-2013-5-604 ◽

2013 ◽

Vol 68 (5-6) ◽

pp. 191-197 ◽

Cited By ~ 2

Author(s):

Birkan Açıkgöz ◽

İskender Karaltı ◽

Melike Ersöz ◽

Zeynep M. Coşkun ◽

Gülşah Çobanoğlu ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Activities ◽

Chloroform Extract ◽

Cytotoxic Effects ◽

Minimal Inhibitory Concentrations ◽

E Coli ◽

Methanol Extracts ◽

Gram Positive Bacteria

The present study explores the antimicrobial activity and cytotoxic effects in culture assays of two fruticose soil lichens, Cladonia rangiformis Hoffm. and Cladonia convoluta (Lamkey) Cout., to contribute to possible pharmacological uses of lichens. In vitro antimicrobial activities of methanol and chloroform extracts against two Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), two Gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus), and the yeast Candida albicans were examined using the paper disc method and through determination of minimal inhibitory concentrations (MICs). The data showed the presence of antibiotic substances in the chloroform and the methanol extracts of the lichen species. The chloroform extracts exhibited more signifi cant antimicrobial activity than the methanol extracts. However, a higher antifungal activity was noted in the methanol extract of C. rangiformis. The maximum antimicrobial activity was recorded for the chloroform extract of C. convoluta against E. coli. The cytotoxic effects of the lichen extracts on human breast cancer MCF-7 cells were evaluated by the trypan blue assay yielding IC50 values of ca. 173 and 167 μg/ml for the extracts from C. rangiformis and C. convoluta, respectively.

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Cecropin A–melittin mutant with improved proteolytic stability and enhanced antimicrobial activity against bacteria and fungi associated with gastroenteritis in vitro

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2014.08.044 ◽

2014 ◽

Vol 451 (4) ◽

pp. 650-655 ◽

Cited By ~ 27

Author(s):

Shengyue Ji ◽

Weili Li ◽

Lei Zhang ◽

Yue Zhang ◽

Binyun Cao

Keyword(s):

Antimicrobial Activity ◽

Cecropin A ◽

Proteolytic Stability ◽

Bacteria And Fungi

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Screening of antimicrobial activity of essential oil and methanol extract of Satureja hortensis on foodborne bacteria and fungi

Czech Journal of Food Sciences ◽

10.17221/753-cjfs ◽

2008 ◽

Vol 25 (No. 2) ◽

pp. 81-89 ◽

Cited By ~ 43

Author(s):

A. Adiguzel ◽

H. Ozer ◽

H. Kilic ◽

B. Cetin

Keyword(s):

Antimicrobial Activity ◽

Chemical Composition ◽

Minimum Inhibitory Concentration ◽

Essential Oil ◽

Inhibitory Concentration ◽

Methanol Extract ◽

Antimicrobial Activities ◽

Satureja Hortensis ◽

Bacteria And Fungi

The present work reports the in vitro antimicrobial activities of the essential oil and methanol extract from Satureja hortensis as well as the content of its essential oil. The chemical composition of hydrodistilled essential oil of Satureja hortensis was analysed by means of GC-MS. Thirty constituents were identified. The main constituents of the oil were thymol (40.54%), γ-terpinene (18.56%), carvacrol (13.98%), and p-cymene (8.97). The essential oil of Satureja hortensis exhibited the activity against 25 bacteria, 8 fungi, and a yeast, C. albicans; exerting the Minimum Inhibitory Concentration values (MIC) ranging from 15.62 to 250 µl/ml. Similarly, methanol extract of the plant also showed antimicrobial activity.

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Phytochemical characterization, anti-cancer and antimicrobial activity of isolated fractions of Alysicarpus vaginalis

Bangladesh Journal of Pharmacology ◽

10.3329/bjp.v12i1.29995 ◽

2017 ◽

Vol 12 (1) ◽

pp. 77 ◽

Cited By ~ 1

Author(s):

Ganesh Tapadiya ◽

Mayura A. Kale ◽

Shweta Saboo

Keyword(s):

Antimicrobial Activity ◽

Cell Lines ◽

Methanolic Extract ◽

Hep G2 ◽

Zone Of Inhibition ◽

E Coli ◽

Anti Cancer ◽

Proliferative Assay ◽

Bacteria And Fungi

The methanolic extract of Alysicarpus vaginalis was selected for fractionation due to its known reported biological activity. The four fractions were separated and subjected for in vitro antimitotic and anti-proliferative assays along with anti-cancer activity on two human cancers cell lines (SK-MEL-2 and Hep-G2). The antimicrobial potential of fractions had been evaluated against bacteria and fungi. From all fractions, acetone and n-butanol fractions were effective against the cell lines. They show strong inhibitory action with mitotic index 6.2 and 8.4 mg/mL and IC50 values of anti-proliferative assay in between 19.7 to 14.2 mg/mL respectively, which was found to be comparable to the standard methothrexate 5.9 mg/mL and 13.2 mg/mL respectively. In antimicrobial activity, the zone of inhibition had been observed in the range of 12-27 mm and MIC value was found in the range of 0.2-0.1 mg/mL. The acetone fraction was found to be most active against fungi, and E. coli whereas chloroform and n-butanol fractions were more effective against S. aureus and B. subtilis. The phytochemical characterization by HPLC analysis indicated the presence of important polyphenolic and steroidal compounds.

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In VitroAntimicrobial Activity of Essential Oil ofThymus schimperi,Matricaria chamomilla,Eucalyptus globulus, andRosmarinus officinalis

International Journal of Microbiology ◽

10.1155/2016/9545693 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 30

Author(s):

Awol Mekonnen ◽

Berhanu Yitayew ◽

Alemnesh Tesema ◽

Solomon Taddese

Keyword(s):

Antimicrobial Activity ◽

Minimum Inhibitory Concentration ◽

Essential Oil ◽

Essential Oils ◽

Inhibitory Concentration ◽

Antimicrobial Activities ◽

Diffusion Method ◽

Drug Preparation ◽

Bacteria And Fungi

In this study, thein vitroantimicrobial activities of four plant essential oils (T. schimperi,E. globulus,R. officinalis, andM. Chamomilla) were evaluated against bacteria and fungi. The studies were carried out using agar diffusion method for screening the most effective essential oils and agar dilution to determine minimum inhibitory concentration of the essential oils. Results of this study revealed that essential oils ofT. schimperi,E. globulus, andR. officinaliswere active against bacteria and some fungi. The antimicrobial effect ofM. chamomillawas found to be weaker and did not show any antimicrobial activity. The minimum inhibitory concentration values ofT. schimperiwere<15.75 mg/mL for most of the bacteria and fungi used in this study. The minimum inhibitory concentration values of the other essential oils were in the range of 15.75–36.33 mg/mL against tested bacteria. This study highlighted the antimicrobial activity of the essential oil ofE. globulus,M. chamomilla,T. Schimperi, andR. officinalis. The results indicated thatT. schimperihave shown strong antimicrobial activity which could be potential candidates for preparation of antimicrobial drug preparation.

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Biosynthesis of Organic Nanocomposite Using Pistacia vera L. Hull: An Efficient Antimicrobial Agent

Bioinorganic Chemistry and Applications ◽

10.1155/2021/4105853 ◽

2021 ◽

Vol 2021 ◽

pp. 1-18

Author(s):

Omolbanin Bakhshi ◽

Ghodsieh Bagherzade ◽

Pouya Ghamari kargar

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Phenolic Compounds ◽

Aspergillus Niger ◽

Essential Oil ◽

Pistacia Vera ◽

X Ray ◽

Vis Spectroscopy ◽

Escherichia Coli Bacteria ◽

Bacteria And Fungi

Here presented a quick and easy synthesis of copper nanoparticles (CuNPs). Pistachio hull extract has been used as a reducing and stabilizing agent in the preparation of CuNPs. This biosynthesis is a kind of supporter of the environment because chemical agents were not used to making nanoparticles, and on the other hand, it prevents the release of pistachio waste in nature and its adverse effects on nature. The biosynthesized CuNPs and CuNPs/silver Schiff base nanocomposite (CSS NC) were characterized by UV-VIS spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS). CuNP and CSS NC antimicrobial activity was examined by both well diffusion and determination MIC methods against four bacteria Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa and two fungi Aspergillus Niger and Candida albicans. CuNPs and CSS NC showed significant antimicrobial activity on the samples, preventing the growth of bacteria and fungi at very low concentrations. CuNPs and CSS NC had the greatest effect on Escherichia coli bacteria and Aspergillus niger fungi. Phenolic compounds are one of the most important antioxidants that are involved in various fields, including pharmacy. Pistacia vera hull is a rich source of phenolic compounds. In this study, the most phenolic compound in Pistacia vera hull is gallic acid and rutin, which has been identified by HPLC analysis. In this study, Pistacia vera hull essential oil analysis was performed by the GC-MS method, in which α-pinene, D-limonene, and isobornyl acetate compounds constitute the highest percentage of Pistacia vera hull essential oil.

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Synthesis, antioxidant and antimicrobial activity of carbohydrazones

Journal of the Serbian Chemical Society ◽

10.2298/jsc161220045b ◽

2017 ◽

Vol 82 (5) ◽

pp. 495-508 ◽

Cited By ~ 9

Author(s):

Aleksandra Bozic ◽

Nenad Filipovic ◽

Irena Novakovic ◽

Snezana Bjelogrlic ◽

Jasmina Nikolic ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antioxidant Activity ◽

Dimethyl Sulphoxide ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Antioxidant Compound ◽

Antioxidant And Antimicrobial Activity ◽

Bacteria And Fungi

Fourteen mono- and bis-carbohydrazone ligands have been synthesized and characterized. Antioxidant activity of the substances was investigated together with possible (E)/(Z) isomerization, and explained on the most active antioxidant compound 4 in various dimethyl sulphoxide?water mixtures. The addition of water to the system was involved in the formation of hydrated molecules which was confirmed in NMR after the addition of D2O. The ligands were tested in vitro against Gram-positive and Gram-negative bacteria and fungi, and their activity was discussed in relation to the structure of investigated carbohydrazone.

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