Synthesis and In Vitro Antimicrobial Evaluation of Photoactive Multi—Block Chalcone Conjugate Phthalimide and 1,8-Naphthalimide Novolacs

Herein we report new multiblock chalcone conjugate phthalimide and naphthalimide functionalized copolymers with a topologically novel architecture synthesis using nucleophilic substitution and polycondensation methodology. The structures of the synthesized novolacs were elucidated on the basis of their spectroscopic analysis including FTIR, 1H NMR, and 13C NMR spectroscopy. Further, the number-average and weight-average molecular weights of the novolac polymers were determined by gel permeation chromatography (GPC). We examined the solubility of the synthesized polymers in various organic solvents including CHCl3, CH3CN, THF, H2O, CH3OH, DMSO, and DMF and found they are insoluble in both methanol and water. The novolac polymers were evaluated for their photophysical properties and microbial activities. The investigation of the antimicrobial activities of these polymers reveals significant antimicrobial activity against the pathogens E. coli, S. aureus, C. albicans, and A. niger.

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SYNTHESIS, CHARACTERIZATION AND IN VITRO ANTIMICROBIAL EVALUATION OF SOME NOVEL BENZIMIDAZOLE DERIVATIVES BEARING HYDRAZONE MOIETY

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10s4.21328 ◽

2017 ◽

Vol 10 (16) ◽

pp. 1

Author(s):

Jayanta Sarma ◽

Gurvinder Singh ◽

Mukta Gupta ◽

Reena Gupta ◽

Bhupinder Kapoor

Keyword(s):

Antibacterial Properties ◽

Antimicrobial Properties ◽

Aromatic Aldehydes ◽

Antibacterial Activities ◽

Antimicrobial Activities ◽

Benzimidazole Derivatives ◽

E Coli ◽

Antimicrobial Evaluation ◽

Antibacterial Potential

Objective: The synthesis of novel benzimidazole-hydrazone derivatives has been carried out based on the previous findings that both these pharmacophores possess potent antimicrobial activities. The antibacterial properties of synthesized derivatives were screened against both Gram-positive and Gram-negative bacteria.Methods: O-phenylenediamine on condensation with substituted aromatic acids in polyphosphoric acid gave benzimidazole nucleus which on reaction with ethyl chloroacetate and hydrazine hydrate in two different steps resulted in the formation of substituted acetohydrazides. The targeted compounds 6a-l were synthesized by reaction of substituted acetohydrazides with aromatic aldehydes and screened for their antibacterial potential by cup-plate method.Results: The synthesized benzimidazole-hydrazones exhibited moderate to strong antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. The compounds 6a-6f were found to be most effective against S. aureus, E. coli, and P. aeruginosa. Among all the synthesized compounds, the zone of inhibition of 6f in highest concentration, i.e., 100 μg/ml were found to be >31 mm against all the stains of bacteria.Conclusion: The antibacterial results revealed that the synthetized derivatives have significant antimicrobial properties and further structure activity relationship studies may develop more potent and less toxic molecules.

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Preventive antimicrobial action and tissue architecture ameliorations of Bacillus subtilis in challenged broilers

Veterinary World ◽

10.14202/vetworld.2021.523-536 ◽

2021 ◽

Vol 14 (2) ◽

pp. 523-536

Author(s):

Essam S. Soliman ◽

Rania T. Hamad ◽

Mona S. Abdallah

Keyword(s):

Bacillus Subtilis ◽

Broiler Chickens ◽

Trichophyton Mentagrophytes ◽

Antimicrobial Activities ◽

Lymphoid Hyperplasia ◽

Bursa Of Fabricius ◽

Tissue Architecture ◽

E Coli

Background and Aim: Probiotics improve intestinal balance through bacterial antagonism and competitive exclusion. This study aimed to investigate the in vitro antimicrobial activity, as well as the in vivo preventive, immunological, productive, and histopathological modifications produced by probiotic Bacillus subtilis. Materials and Methods: The in vitro antimicrobial activities of B. subtilis (5×106 CFU/g; 0.5, 1.0*, 1.5, and 2.0 g/L) were tested against Escherichia coli O157: H7, Salmonella Typhimurium, Candida albicans, and Trichophyton mentagrophytes after exposure times of 0.25, 0.5, 1, and 2 h using minimal inhibitory concentration procedures. A total of 320 1-day-old female Ross broiler chickens were divided into five groups. Four out of the five groups were supplemented with 0.5, 1.0*, 1.5, and 2.0 g/L probiotic B. subtilis from the age of 1 day old. Supplemented 14-day-old broiler chickens were challenged with only E. coli O157: H7 (4.5×1012 CFU/mL) and S. Typhimurium (1.2×107 CFU/mL). A total of 2461 samples (256 microbial-probiotic mixtures, 315 sera, 315 duodenal swabs, and 1575 organs) were collected. Results: The in vitro results revealed highly significant (p<0.001) killing rates at all-time points in 2.0 g/L B. subtilis: 99.9%, 90.0%, 95.6%, and 98.8% against E. coli, S. Typhimurium, C. albicans, and T. mentagrophytes, respectively. Broilers supplemented with 1.5 and 2.0 g/L B. subtilis revealed highly significant increases (p<0.01) in body weights, weight gains, carcass weights, edible organs' weights, immune organs' weights, biochemical profile, and immunoglobulin concentrations, as well as highly significant declines (p<0.01) in total bacterial, Enterobacteriaceae, and Salmonella counts. Histopathological photomicrographs revealed pronounced improvements and near-normal pictures of the livers and hearts of broilers with lymphoid hyperplasia in the bursa of Fabricius, thymus, and spleen after supplementation with 2.0 g/L B. subtilis. Conclusion: The studies revealed that 1.5-2.0 g of probiotic B. subtilis at a concentration of 5×106 CFU/g/L water was able to improve performance, enhance immunity, and tissue architecture, and produce direct antimicrobial actions.

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Design and Synthesis of Novel Sulfonamide-Derived Triazoles and Bioactivity Exploration

Medicinal Chemistry ◽

10.2174/1573406414666181106124852 ◽

2020 ◽

Vol 16 (1) ◽

pp. 104-118 ◽

Cited By ~ 2

Author(s):

Shi-Chao He ◽

Hui-Zhen Zhang ◽

Hai-Juan Zhang ◽

Qing Sun ◽

Cheng-He Zhou

Keyword(s):

Chlorosulfonic Acid ◽

Antibacterial Activities ◽

Structural Features ◽

The Novel ◽

E Coli ◽

Design And Synthesis ◽

Chemical Studies ◽

Antimicrobial Evaluation ◽

Better Than

Objective: Due to the incidence of resistance, a series of sulfonamide-derived 1,2,4- triazoles were synthesized and evaluated. Method: The novel sulfonamide-derived 1,2,4-triazoles were prepared starting from commercial acetaniline and chlorosulfonic acid by sulfonylation, aminolysis, N-alkylation and so on. The antimicrobial activity of the synthesized compounds were evaluated in vitro by two-fold serial dilution technique. Results: In vitro antimicrobial evaluation found that 2-chlorobenzyl sulfonamide 1,2,4-triazole 7c exhibited excellent antibacterial activities against MRSA, B. subtilis, B. typhi and E. coli with MIC values of 0.02−0.16 μmol/mL, which were comparable or even better than Chloromycin. The preliminary mechanism suggested that compound 7c could effectively bind with DNA, and also it could bind with human microsomal heme through hydrogen bonds in molecular docking. Computational chemical studies were performed on compound 7c to understand the structural features that are essential for activity. Additionally, compound 7c could generate a small amount of reactive oxygen species (ROS). Conclusion: Compound 7c could serve as a potential clinical antimicrobial candidate.

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Biosurfactants Induce Antimicrobial Peptide Production through the Activation of TmSpatzles in Tenebrio molitor

International Journal of Molecular Sciences ◽

10.3390/ijms21176090 ◽

2020 ◽

Vol 21 (17) ◽

pp. 6090

Author(s):

Tariku Tesfaye Edosa ◽

Yong Hun Jo ◽

Maryam Keshavarz ◽

In Seon Kim ◽

Yeon Soo Han

Keyword(s):

Antimicrobial Peptide ◽

Immune Activation ◽

Tenebrio Molitor ◽

Antimicrobial Activities ◽

Iturin A ◽

E Coli ◽

Fat Bodies ◽

Escherichia Coli Bacteria ◽

Bacteria And Fungi

Biosurfactant immunomodulatory activities in mammals, nematodes, and plants have been investigated. However, the immune activation property of biosurfactants in insects has not been reported. Therefore, here, we studied the defense response triggered by lipopeptides (fengycin and iturin A), glycolipids (rhamnolipid), and cyclic polypeptides (bacitracin) in the coleopteran insect, mealworm Tenebrio molitor. The in vitro antimicrobial activities against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria and fungi (Candida albicans) were assessed by mixing these pathogens with the hemolymph of biosurfactant-immune-activated larvae. E. coli growth was remarkably inhibited by this hemolymph. The antimicrobial peptide (AMP) induction results also revealed that all biosurfactants tested induced several AMPs, exclusively in hemocytes. The survivability analysis of T. molitor larvae challenged by E. coli (106 CFU/µL) at 24 h post biosurfactant-immune activation showed that fengycin, iturin A, and rhamnopid significantly increased survivability against E. coli. Biosurfactant-induced TmSpatzles activation was also monitored, and the results showed that TmSpz3 and TmSpz-like were upregulated in the hemocytes of iturin A-injected larvae, while TmSpz4 and TmSpz6 were upregulated in the fat bodies of the fengycin-, iturin A-, and rhamnolipid-injected larvae. Overall, these results suggest that lipopeptide and glycolipid biosurfactants induce the expression of AMPs in T. molitor via the activation of spätzle genes, thereby increasing the survivability of T. molitor against E. coli.

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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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Methylene-Bridged Tridentate Salicylaldiminato Binuclear Titanium Complexes as Copolymerization Catalysts for the Preparation of LLDPE through [Fe]/[Ti] Tandem Catalysis

Polymers ◽

10.3390/polym11071114 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1114 ◽

Cited By ~ 2

Author(s):

Yani Luo ◽

Jian Li ◽

Derong Luo ◽

Qingliang You ◽

Zifeng Yang ◽

...

Keyword(s):

Molecular Weight ◽

High Temperature ◽

Gel Permeation Chromatography ◽

13C Nmr Spectroscopy ◽

Molar Ratio ◽

Tandem Catalysis ◽

Titanium Complexes ◽

Scanning Calorimetry ◽

Molecular Weights ◽

Branching Degree

A novel tandem catalysis system consisted of salicylaldiminato binuclear/mononuclear titanium and 2,6-bis(imino)pyridyl iron complexes was developed to catalyze ethylene in-situ copolymerization. Linear low-density polyethylene (LLDPE) with varying molecular weight and branching degree was successfully prepared with ethylene as the sole monomer feed. The polymerization conditions, including the reaction temperature, the Fi/Ti molar ratio, and the structures of bi- or mononuclear Ti complexes were found to greatly influence the catalytic performances and the properties of obtained polymers. The polymers were characterized by differential scanning calorimetry (DSC), high temperature gel permeation chromatography (GPC) and high temperature 13C NMR spectroscopy, and found to contain ethyl, butyl, as well as some longer branches. The binuclear titanium complexes demonstrated excellent catalytic activity (up to 8.95 × 106 g/molTi·h·atm) and showed a strong positive comonomer effect when combined with the bisiminopyridyl Fe complex. The branching degree can be tuned from 2.53 to 22.89/1000C by changing the reaction conditions or using different copolymerization pre-catalysts. The melting points, crystallinity and molecular weights of the products can also be modified accordingly. The binuclear complex Ti2L1 with methylthio sidearm showed higher capability for comonomer incorporation and produced polymers with higher branching degree and much higher molecular weight compared with the mononuclear analogue.

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Synthesis and in vitro Biological Activity of New 4,6-Disubstituted 3(2H)-Pyridazinone-acetohydrazide Derivatives

Zeitschrift für Naturforschung C ◽

10.1515/znc-2012-5-604 ◽

2012 ◽

Vol 67 (5-6) ◽

pp. 257-265

Author(s):

Murat Sukuroglu ◽

Tijen Onkol ◽

Fatma Kaynak Onurdağ ◽

Gulsen Akalın ◽

M. Fethi Şahin

Keyword(s):

Biological Activity ◽

Antimicrobial Activities ◽

Cytotoxic Activities ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

Preliminary Results ◽

H Nmr ◽

Pyridazinone Derivatives

New 3(2H)-pyridazinone derivatives containing a N’-benzyliden-acetohydrazide moiety at position 2 were synthesized. The structures of these newly synthesized compounds were confi rmed by IR, 1H NMR, and MS data. These compounds were tested for their antibacterial, antifungal, antimycobacterial, and cytotoxic activities. The compounds 2-[4-(4-chlorophenyl)- 6-(morpholin-4-yl)-3-oxo-(2H)-pyridazin-2-yl]-N’-(4-tert-butylbenzyliden)acetohydrazide and 2-[4-(4-chlorophenyl)-6-(morpholin-4-yl)-3-oxo-(2H)-pyridazin-2-yl]-N’-(4-chlorobenzyliden) acetohydrazide exhibited activity against both Gram-positive and Gram-negative bacteria. Most of the compounds were active against E. coli ATCC 35218. The preliminary results of this study revealed that some target compounds exhibited promising antimicrobial activities

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Selection and Evaluation of Potential Probiotic Lactic Acid Bacteria and Bifidobacteria Isolated from Human Intestinal Tract

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.910.137 ◽

2014 ◽

Vol 910 ◽

pp. 137-140

Author(s):

Chao Hui Xue ◽

Lan Wei Zhang ◽

Hong Bo Li ◽

Shu Mei Wang

Keyword(s):

Lactobacillus Rhamnosus ◽

Antimicrobial Activities ◽

E Coli ◽

Probiotic Potential ◽

Probiotic Lactic Acid Bacteria ◽

Probiotic Strains ◽

Health Promoting ◽

Culture Supernatants ◽

Ht 29

Three Lactobacillus strains were screened on the basis of probiotic characteristics (i.e., resistance to low pH and bile salts, adhesion to the human gastrointestinal tract, inhibition of pathogenic strains). They further exhibited producing antimicrobial activities of non-acid molecule (s). In addition, antibacterial peptides were isolated and purified from the cell-free culture supernatants of these three probiotic strains. Based on TricineSDSPAGE, the antimicrobial peptide was approximately 10 kDa in size. After analyzing the sequence of the 16SrDNA regions of these three strains, they were identified asLactobacillus crispatus Lactobacillus rhamnosus and Lactobacillus rhamnosua GG.Using an in vitro system simulating gastric transit, our findings indicated that the three probiotic strains had the ability to tolerate gastroenteric environment and the adhesive capacity to HT-29 cells. It was demonstrated that the probiotic strains inhibited subsequent adhesion of E. coli to the HT-29 cell. Among the selected strains,L. rhamnosusF1333 showed a high probiotic potential and could be used in health-promoting food products.

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Synthesis, Characterization, and Thermal and Antimicrobial Activities of Some Novel Organotin(IV): Purine Base Complexes

Journal of Chemistry ◽

10.1155/2013/568195 ◽

2013 ◽

Vol 2013 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Reena Jain ◽

Rajeev Singh ◽

N. K. Kaushik

Keyword(s):

Antimicrobial Agents ◽

Rhizopus Oryzae ◽

Antimicrobial Activities ◽

Spectral Studies ◽

Purine Base ◽

Mass Spectral ◽

E Coli ◽

Kinetic And Thermodynamic Parameters ◽

C Nmr

A new series of organotin(IV) complexes with purine bases theophylline (HL1) and theobromine (L2) of the types R3Sn(L1), R2Sn(L1)Cl, R3Sn(L2)Cl, and R2Sn(L2)Cl2(R = C6H5CH2–;p-ClC6H4CH2–) have been synthesized in anhydrous THF. The complexes were characterized by elemental analysis, conductance measurements, molecular weight determinations, UV-vis, IR,1H,13C NMR, and mass spectral studies. Various kinetic and thermodynamic parameters of these complexes have also been determined using TG/DTA technique. The thermal decomposition techniques indicate the formation of SnO2as a residue. The results show that the ligands act as bidentate, forming a five-member chelate ring. All the complexes are 1 : 1 metal-ligand complexes. In order to assess their antimicrobial activity, the ligands and their corresponding complexes have also been testedin vitroagainst bacteria (E. coli, S. aureus, andP. pyocyanea) and fungi (Rhizopus oryzaeandAspergillus flavus). All the complexes exhibit remarkable activity, and the results provide evidence that the studied complexes might indeed be a potential source of antimicrobial agents.

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Synthesis of sulfonamides bearing 1,3,5-triarylpyrazoline and 4-thiazolidinone moieties as novel antimicrobial agents

Journal of the Serbian Chemical Society ◽

10.2298/jsc180621057t ◽

2020 ◽

Vol 85 (2) ◽

pp. 155-162

Author(s):

Thi-Dan Thach ◽

Thi Le ◽

Thien-Annguyen Nguyen ◽

Chi-Hien Dang ◽

Van-Su Dang ◽

...

Keyword(s):

Antimicrobial Agents ◽

Antimicrobial Activities ◽

Significant Inhibition ◽

Mercaptoacetic Acid ◽

Bacterial Strains ◽

Reference Drug ◽

E Coli ◽

Yeast Strains ◽

Microbial Strains

Two series of sulfonamides were synthesized from 4-hydrazinylbenzenesulfonamide as the key starting material. 1,3,5-Triarylpyrazoline sulfonamides (2a?i) were obtained by cyclocondensation of various chalcones in 53? ?64 % yields, while 4-thiazolidinone derivatives (4a?e) were synthesized by cyclocondensation between mercaptoacetic acid and different phenylhydrazones in 43?62 % yields. The synthesized compounds were characterized based on FTIR, 1H-NMR, 13C-NMR and HRMS data. The sulfonamides were evaluated for their in vitro antimicrobial activities against four bacterial strains (E. coli, P. aeruginosa, B. subtillis and S aureus), two filamentous fungal strains (A. niger and F. oxysporum) and two yeast strains (C. albicans and S. cerevisiae). Seven pyrazolines, 2a?c and 2e?h, exhibited significant inhibition of different microbial strains. Among them, compound 2b displayed good antifungal activity against A. niger (MIC value at 12.5 ?g mL-1) over the reference drug.

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