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Two novel metal complexes, C1 and C2, were synthesized through the reaction of an azo dye ligand, obtained by coupling 4‐chloroaniline with 1,3‐dimethyl barbituric acid. The structure of the ligand was confirmed using Fourier‐transform infrared spectroscopy (FTIR) and Nuclear magnetic resonance (NMR). UV–Vis spectroscopy was employed to assess the ligand's sensing ability toward six different metal ions. Comprehensive characterization of the synthesized metal complexes was conducted using elemental analysis, X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis–difference thermogravimetry (TGA‐DTG), FTIR, UV–Vis spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and single‐crystal X‐ray diffraction (SC‐XRD). X‐ray analysis revealed octahedral coordination geometry with a 2:1 ligand‐to‐metal ratio and dimethylformamide (DMF) coordination with the metal atom in both complexes. Hirshfeld analysis and 2D fingerprint plots were employed to investigate supramolecular and intermolecular interactions within the crystal system. Density functional theory (DFT/B3LYP) calculations were utilized to compute energy gaps and other important theoretical features. Sensing experiments with tetrabutylammonium fluoride (TBAF) were conducted at a concentration of 1 × 10−5 M. Furthermore, the bioactivity of the synthesized metal complexes and ligand L was evaluated through molecular docking studies against Protein Data Bank (PDB IDs) 4XUY (Staphylococcus aureus) and 3BQW (Aspergillus niger). Also, antimicrobial activity was assessed using the agar well diffusion technique, revealing that complexes C1 and C2 exhibited enhanced antimicrobial activities against the tested organisms compared to the parent azo dye ligand. The computational and experimental bioactivity data are in good agreement with each other. [ABSTRACT FROM AUTHOR]

Objective: The tandem Knoevenagel-cyclocondensation reaction of aromatic aldehydes, malonitrile, and phenylhydrazine in water and ethanol at room temperature is described as an effective, one-pot, threecomponent synthesis of many scientifically relevant heterocyclic compounds. Methods: As a part of our efforts, we have synthesized pyrazole-4-carbonitriles and characterized using various spectroscopic methods and subjected for antimicrobial analysis. Results and Discussion: From our analysis, we observed best in vitro candidate as 5-amino-3-(2,5-difluorophenyl)-1-phenyl-1H-pyrazole-4-carbonitrile. The molecular docking analysis on common bacterial target suggested the involvement of 2,2-dialkylglycine decarboxylase (PDB ID: 1D7U) as a target for compound (IVi) (docking score: –9.32 kcal/mol). Furthermore, a molecular dynamic simulation of 100 ns resulted in the stability of best docked candidate, (IVi): 1D7U. Conclusions: We propose that best docked candidate, (IVi) as potential antimicrobial agents. [ABSTRACT FROM AUTHOR]

We successfully produced imidazolium aldehydes from imidazolium alcohols for the first time using copper wire and no oxidizing agents. The findings of IR, UV, ¹H-NMR, and 13CNMR spectral examinations all indicated complete oxidation of the alcohols, which was further demonstrated by those findings. The oxidation technique was used to create the ionic liquids 1-Ethyl-3-methyl-2-(2-oxo-ethyl)-3H-imidazol-1-ium; bromide and 1-Butyl-3-methyl-2-(2-oxo-ethyl)-3H-imidazol-1-ium; chloride. Using elemental and spectral analyses confirmed the structure of the synthesized compounds (I) and (II). FT-IR analysis was used to determine the presence of functional groups in the grown samples (I) and (II), and ¹HNMR and 13C-NMR spectral analysis were performed to confirm the environment of the elements (C, H). A UV-Visible-NIR spectrophotometer was implemented to determine the optical absorption value for samples (I) and (II). Using DSC analysis, the thermal stability and decomposition were seen. Bacillus Cereus, Staphylococcus Aureus, Enterobacter Coacae, and Staphylococcus Haemolytics were used in an antimicrobial study for samples (I) and (II), and the results are compared with control Ciprofloxacin. [ABSTRACT FROM AUTHOR]

The main goal of this investigation is to conduct a thorough analysis of the physical, chemical, and morphological characteristics of chitosan derived from various forest fungi. Additionally, the study aims to determine the effectiveness of this vegetal chitosan as an antimicrobial agent. In this study, Auricularia auricula-judae, Hericium erinaceus, Pleurotus ostreatus, Tremella fuciformis, and Lentinula edodes were examined. The fungi samples were subjected to a series of rigorous chemical extraction procedures, including demineralization, deproteinization, discoloration, and deacetylation. Subsequently, the chitosan samples were subjected to a comprehensive physicochemical characterization analysis, encompassing Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), degree of deacetylation determination, ash content determination, moisture content determination, and solubility determination. To evaluate the antimicrobial efficacy of the vegetal chitosan samples, two different sampling parameters were employed, namely human hand and banana, to assess their effectiveness in inhibiting microbial growth. Notably, the percentage of chitin and chitosan varied significantly among the distinct fungal species examined. Moreover, EDX spectroscopy confirmed the extraction of chitosan from H. erinaceus, L. edodes, P. ostreatus, and T. fuciformis. The FTIR spectra of all samples revealed a similar absorbance pattern, albeit with varying peak intensities. Furthermore, the XRD patterns for each sample were nearly identical, with the exception of the A. auricula-judae sample, which exhibited sharp peaks at ~37° and ~51°, while the crystallinity index of this same sample was approximately 17% lower than the others. The moisture content results indicated that the L. edodes sample was the least stable, while the P. ostreatus sample was the most stable, in terms of degradation rate. Similarly, the solubility of the samples showed substantial variation among each species, with the H. erinaceus sample displaying the highest solubility among the rest. Lastly, the antimicrobial activity of the chitosan solutions exhibited different efficacies in inhibiting microbial growth of skin microflora and microbes found on the peel of Musa acuminata × balbisiana. [ABSTRACT FROM AUTHOR]

Gemechu Ameya,1,2 Aseer Manilal,3 Kuzhunellil Raghavanpillai Sabu,4 Solomon Aragie2 1Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Kotebe Metropolitan University, Addis Ababa, Ethiopia; 2Department of Cellular, Microbial, and Molecular Biology, College of Natural and Computational Sciences, Addis Ababa University, Addis Ababa, Ethiopia; 3Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia; 4Department of Chemistry, College of Natural and Computational Sciences, Arba Minch University, Arba Minch, EthiopiaCorrespondence: Gemechu Ameya, Email gemechuameya@gmail.comBackground: In spite of the great advances in modern medicine in recent decades, medicines of plant origin are still in use for several ailments in different parts of the world. There is always an urge to develop novel, effective and inexpensive antimicrobials. This study was aimed to evaluate the antimicrobial activity and phytochemical composition of the leaf extract of Clematis hirsuta against selected human bacterial and fungal pathogens.Methods: The crude extracts of C. hirsuta leaves were prepared with five different solvents of varying polarity. Agar well diffusion assay on five different species of ATCC organisms, four clinical bacterial isolates, and four clinically isolated fungi were performed. The tube dilution method was used to determine the minimum inhibitory concentrations and the selected extract was subjected to bio-assay-guided fractionation using column chromatography and the active fraction obtained were pooled and GC-MS, FT-IR, and CHN analysis were conducted, and this study is actually bioassay-guided research.Results: A varying patterns of antimicrobial activity against tested microorganism was observed. Acetone extract showed the highest spectrum of activity (17– 32mm) in the well diffusion assay against bacteria and 16– 23mm in the case of fungi. The MIC ranged from 7.5– 60 mg/mL in the case of bacteria and 15– 60 mg/mL against fungi. The bioassay-guided column chromatography of the acetone extract followed by GC-MS showed the presence of three major compounds, specifically O-ethylhydroxylamine (43%), 2-ethyl heptanoic acid (20.6%), and 1-nonyl cycloheptane (19.5%). The finding was confirmed by FT-IR and elemental analysis of TLC-separated fractions.Conclusion: The acetone extract showed better antimicrobial activity and the least minimum inhibition concentrations against bacteria compared to fungi. The observed antibacterial can be assigned to the presence of alkoxy amine, alkyl aliphatic acids, and cycloalkane. The overall findings substantiate the traditional usages of the parts of this plant, especially the leaves, in managing infectious diseases.Keywords: antimicrobial analysis, Clematis hirsuta, pathogenic organisms, phytochemical analysis

A novel polyvinylpyrrolidone oxime and titanium dioxide nanocomposite (PVPO-TiO2 NC)-based enzymeless glucose sensing electrode was fabricated and characterized to evaluate its performance. A facile sol–gel approach was adopted to fabricate the NCs as a novel product. PVPO-TiO2 NCs were coated onto the surface of a graphite sheet electrode using a drop-casting method. The NCs and modified electrode were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), ultraviolet–visible (UV–Vis) spectroscopy, scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), tunneling electron microscopy (TEM), and zeta potential measurements for their structural, morphological, and spectral analysis. The electrochemical behavior of the modified PVPO-TiO2/G electrode was studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA). The modified electrode demonstrated high sensitivity of 62.79 µA/mMcm2, a low detection limit of 445.3 µM, and a linear range of 0–16 mM with a regression coefficient R2 = 0.982. Also, this composite electrode delivered good stability, anti-interference ability with species including fructose, ascorbic acid (AA), and uric acid (UA), and effective detection in common beverage samples. In addition, PVPO-TiO2 NCs effectively inhibited harmful pathogenic bacteria including Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Shigella flexneri in antimicrobial analysis. Subsequently, PVPO-TiO2 NCs, due to their dual functionality, proved to be an efficient glucose sensor as well as a good inhibitor against these problematic microbes. In this way, the novel composite obtained through this approach may be recommended to provide better performance, with bifunctional behavior toward both glucose sensing and inhibition of harmful microbes. [ABSTRACT FROM AUTHOR]

The quest for eco-friendly synthetic routes that can be used for the development of multifunctional materials, in particular for water treatment, has reinforced the use of plant extracts as replacement solvents in their use as reducing and capping agents during the synthesis of green derived materials. Amongst the various nanoparticles, Zinc Oxide (ZnO) has emerged as one of the preferred candidates for photocatalysis due to its optical properties. Moreover, ZnO has also been reported to possess antimicrobial properties against various bacterial strains such as E. coli and S. aureus. In this review, various types of pollutants including organic dyes and natural pollutants are discussed. The treatment methods that are used to purify wastewater with their limitations are highlighted. The distinguishing properties of ZnO are clearly outlined and defined, not to mention the performance of ZnO as a green derived photocatalyst and an antimicrobial agent, as well. Lastly, an overview is given of the challenges and possible further perspectives. [ABSTRACT FROM AUTHOR]

The main goal of this investigation is to conduct a thorough analysis of the physical, chemical, and morphological characteristics of chitosan derived from various forest fungi. Additionally, the study aims to determine the effectiveness of this vegetal chitosan as an antimicrobial agent. In this study, Auricularia auricula-judae, Hericium erinaceus, Pleurotus ostreatus, Tremella fuciformis, and Lentinula edodes were examined. The fungi samples were subjected to a series of rigorous chemical extraction procedures, including demineralization, deproteinization, discoloration, and deacetylation. Subsequently, the chitosan samples were subjected to a comprehensive physicochemical characterization analysis, encompassing Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), degree of deacetylation determination, ash content determination, moisture content determination, and solubility determination. To evaluate the antimicrobial efficacy of the vegetal chitosan samples, two different sampling parameters were employed, namely human hand and banana, to assess their effectiveness in inhibiting microbial growth. Notably, the percentage of chitin and chitosan varied significantly among the distinct fungal species examined. Moreover, EDX spectroscopy confirmed the extraction of chitosan from H. erinaceus, L. edodes, P. ostreatus, and T. fuciformis. The FTIR spectra of all samples revealed a similar absorbance pattern, albeit with varying peak intensities. Furthermore, the XRD patterns for each sample were nearly identical, with the exception of the A. auricula-judae sample, which exhibited sharp peaks at ~37° and ~51°, while the crystallinity index of this same sample was approximately 17% lower than the others. The moisture content results indicated that the L. edodes sample was the least stable, while the P. ostreatus sample was the most stable, in terms of degradation rate. Similarly, the solubility of the samples showed substantial variation among each species, with the H. erinaceus sample displaying the highest solubility among the rest. Lastly, the antimicrobial activity of the chitosan solutions exhibited different efficacies in inhibiting microbial growth of skin microflora and microbes found on the peel of Musa acuminata × balbisiana.

In this present work, the crystals of β and α polymorphs of L-glutamic acid were grown by the slow evaporation method with addion of ammonium chloride. The selective additive ammonium chloride was mixed at proportions 0.01 g, 0.02 g, 0.03 g,..., 0.10 g into the L-glutamic acid aqueous solution to find out the α and β polymorphs of L-glutamic acid. The lower proportion (0.01 g) of ammonium chloride yields β polymorph, whereas higher proportion (0.08 g) of ammonium chloride yields α polymorph of L-glutamic acid that was confirmed by powder XRD studies. UV–Vis–NIR spectral analysis shows a good optical transparency of the grown crystals of α and β polymorphs in visible and infrared regions. The functional groups present in the crystal were identified by Fourier-transform infrared spectroscopy (FTIR) analysis. The antibacterial activities of grown crystals against Gram-negative bacterial strains were carried out using the agar disk diffusion method. The anticancer activity study shows that both polymorphs inhibit the human breast cancer cell line. [ABSTRACT FROM AUTHOR]

Scientists are indeed fascinated by the pharmacologically important chemicals found in medicinal plants. Citrus fruits possess several curing agents for the prevention of diseases. Therefore, experiments were carried out to test the antibacterial activity of methanolic extracts of peels from various locally available citrus fruits such as citron (Citrus medica), satkora (Citrus macroptera) and adajamir (Citrus assamensis) against Bacillus spp. and E. coli using the disc diffusion method. Different physicochemical characteristics of fruit juice were also determined. Methanolic extract of satkora peel had the highest antibacterial activity of 2.2 and 2.6 cm while adajamir had the lowest antibacterial activity of 1.7 and 2.1 cm as ZOI against Bacillus spp. and E. coli, respectively. In the case of pH and total soluble solids (TSS), the three citrus varieties showed a small variation where satkora showed the highest total phenolic content (TPC), vitamin C content, and antioxidant activity than the others. Citrus fruits can be exploited as antibacterial and antioxidant ingredients in food and nutraceuticals, according to the findings of this study.

[Display omitted] • Synthesized two copper coordination compounds, ML1 and ML2, characterized using FTIR, EPR, and SC-XRD. • Nitrate anion crucial for distinct supramolecular clusters in both ML1 and ML2. • The crystal structure of ML1 displays a polymeric 1D chain with π-π stacking and H-bonding interactions, while ML2 exhibits a crystal structure with distorted octahedral coordination geometry, featuring nitrate compensating positive charge. • EPR spectroscopy confirms T 2 g6 and Eg3 electron configurations. • Hirshfeld surface analysis reveals H⋅⋅⋅O, H⋅⋅⋅N, and H⋅⋅⋅S interactions as significant in both complexes. • Quantum calculations show that the optimized geometries align well with experimentally determined bond lengths. • ML1 shows superior binding affinities to ML2 against E. coli and C. albicans receptors, with binding energies (-8.5 kcal mol-1 for E. coli, −9.2 kcal mol-1 for C. albicans) comparable to ofloxacin and itraconazole. • ML1 and ML2 exhibit potent antimicrobial properties against S. aureus, E. coli, P. aeruginosa, A. niger, A. flavus, and C. albicans, highlighting their potential for developing effective antimicrobial compounds. In this work, two copper coordination compounds, ([Cu(phen)(L)(OH)(NO 3)]NO 3 –) (ML1) and ([Cu(L) 4 (H 2 O) 2)](NO 3 –) 2) (ML2) , have been synthesized and characterized (SC-XRD). ML1 is a long polymeric chain with a stable distorted octahedral geometry that is assembled from ligands such as 1,10-phenanthroline (Phen), 2-amino-5-methyl-1,3,4-thiadiazole (L), hydroxide (OH), and nitrate (NO 3 –). In contrast, ML2 is made up of water molecules and L ligands, forming the usual octahedral geometry. Furthermore, in the crystal structures of ML1 and ML2 , the nitrate anion is essential for the formation of distinct supramolecular clusters. To confirm the structural integrity, we applied Hirshfeld surface analysis and Density Functional Theory (DFT) computations. We also evaluated the antibacterial efficacy of these compounds computationally and experimentally, which confirmed their potential to serve as potent inhibitors of drug-resistant microbial infections. [ABSTRACT FROM AUTHOR]

The quest for eco-friendly synthetic routes that can be used for the development of multifunctional materials, in particular for water treatment, has reinforced the use of plant extracts as replacement solvents in their use as reducing and capping agents during the synthesis of green derived materials. Amongst the various nanoparticles, Zinc Oxide (ZnO) has emerged as one of the preferred candidates for photocatalysis due to its optical properties. Moreover, ZnO has also been reported to possess antimicrobial properties against various bacterial strains such as E. coli and S. aureus. In this review, various types of pollutants including organic dyes and natural pollutants are discussed. The treatment methods that are used to purify wastewater with their limitations are highlighted. The distinguishing properties of ZnO are clearly outlined and defined, not to mention the performance of ZnO as a green derived photocatalyst and an antimicrobial agent, as well. Lastly, an overview is given of the challenges and possible further perspectives.

Recurrent prosthesis fracture and microbial contamination of the tissue bed or prosthetic materials remain the major clinical challenge for successful intraoral/faciomaxillary rehabilitation. Biocompatible and biofilm-resistant silver nanoparticle (AgNPs) based on poly(methyl methacrylate) was successfully developed by a compression-molding technique. The AgNP-loaded PMMA were characterized using TEM, SEM, FT-IR and XRD analysis. The nanocomposites were found to be biocompatible and biofilm-resistant against Streptococcus mutans and Candida albicans. Mechanical performance of the nanocomposite was statistically analysed and modulus of elasticity was theoretically predicted using four models. The biomaterial developed in this study can be effectively used for stomatognathic rehabilitation. [ABSTRACT FROM AUTHOR]

Ceramic-metal (CaO·Al 2 O 3 –Al and CaO·Al 2 O 3 –Ag) compounds were prepared by mechanical milling and consolidated through an in-situ sintering process. The aim of this work is to study the effects of the Al and Ag particles to ceramic-base compound, primarily in the microstructure, and its mechanical and antimicrobial properties. Chemical systems with a 1:1 M ratio between CaCO 3 and Al 2 O 3 powder were formed, with the addition of 10 wt% Al or 10 wt% Ag, respectively. The compound material that consolidated were microstructurally characterized through X-ray diffraction, scanning electron microscopy, optic microscopy, and X-ray computed tomography. In addition, the hardness, the fracture toughness, the transversal elastic modulus, and the antimicrobial property were evaluated. The results of X-ray diffraction identified the formation of the calcium aluminate phases, such as CaO·6Al 2 O 3 (hibonite:CA6), CaO·2Al 2 O 3 (grossite:CA2), and CaO·Al 2 O 3 (krotite:CA); as well as Al and Ag were identified in its respective system. In addition, the mechanical properties show changes compared to the reference material that was synthesized under the same conditions and, finally, these materials also have an antimicrobial effect, against the Staphylococcus bacterium that is common in the oral cavity, when studied in synthetic saliva. • The synthesis of a novel CaCO 3 ·Al 2 O 3 –Al or Ag from a natural source of CaCO 3 is feasible. • Metallic particles have an effect in mechanical properties on the calcium aluminate matrix. • Calcium aluminate-Ag have an antimicrobial property evaluated in saliva synthetic. [ABSTRACT FROM AUTHOR]

Several per-O-acetyl and per-O-benzoyl glycosylthiocarbamides were synthesized by the interaction of glycosylisothiocyanates and o-phenylenediamine. While these thiocarbamideson further reactions with anisaldehyde give respective benzylidene derivatives. The identities of these newly synthesized compounds were established on the basis of usual chemical transformations, IR, ¹H NMR, 13C NMR and Mass spectral studies. All the synthesized compounds have been evaluated for their antibacterial and antifungal activity against different bacteria and fungi by the agar diffusion method. [ABSTRACT FROM AUTHOR]

In the present work antibacterial effect of NCO (Nano-Cerium Oxide) particles on E.Coli (Escherichia Coli) Bacteria was studied. NCO (Nano Cerium Oxide) particles were synthesized via microwave induced combustion method. XRD (X-Ray Diffraction), SEM (Scanning Electron Microscope) and FTIR (Fourier Transform Infrared Spectroscopy) characterized. NCO particles. Using Scherrer equation it was noted that NCO particles of 14-25 nm size were produced. The SEM and XRD results showed that size of NCO particles was decreased with increasing synthesization time. Synthesization time played vital role on the size of NCO particles. It was also noted that antibacterial action of NCO particles is size dependent. Antibacterial study through disc diffusion method revealed that NCO particles enhanced the efficiency of Amikin Grasil, Terivid and spraxin drugs against the E.Coli bacteria appreciably. [ABSTRACT FROM AUTHOR]

pABA (p-aminobenzoic acid or 4-aminobenzoic acid) is a chemical component of the folate molecule produced by plants and bacteria, and found in many foods. It is best known as a UV-blocking sunscreen applied to the skin, and is sometimes taken orally for certain medical conditions. Today it is known that many organic molecules in the human body can react with biometals such as copper, cobalt, manganese, iron and others. This study was performed to investigate the interaction of Cu(II) ions with p-aminobenzoic acid. Spectroscopic methods (FTIR and UV/Vis spectroscopy) were used to characterize the product obtained. The antimicrobial activity of the synthesized complex was tested by diffusion techniques. The results of spectroscopic analysis indicate the interaction of Cu(II) ions with pABA. Interaction is realized through oxygen donor atom of ligand. It was found that the Cu(II) complex has significant antimicrobial activity compared to the pABA ligand. [ABSTRACT FROM AUTHOR]

Nanoparticles of zinc oxide (ZnO) were added to poly( ε -caprolactone) (PCL), and PCL/ZnO casting films were produced, afterwards films were characterized using Fourier Transform Infrared Spectroscopy (FTIR), x-ray Diffraction (XRD), Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Additionally, antimicrobial and cytotoxic parameters were determined using microbial adhesion testing according to JIS Z 2801: 2000 (E) and agar diffusion method according to ISO 10993-5 2009 , respectively. From collected data, the chemical identity of individual components was kept and the surface control could be achieved changing the composition. According to FTIR spectra and using the Lambert-Beer law higher interaction ratios were met for higher ZnO content which is linked to antimicrobial action. As revealed by AFM analysis, at 5% of ZnO, nanoparticles were well dispersed in PCL matrix with uniform surface film. Analyses from antibacterial activity and cytotoxicity suggested pathogenic Staphylococcus aureus growth was hindered in ZnO films; specifically for PCL/ZnO 5% optimal antibacterial activity and toxicity absent were reached. Summing up, PCL/ZnO5% nanocomposites films offer great potential for commercial applications as active food packaging.

Silver nanoparticles (SNPs) were synthesised by using the Arial part extract of Dorema ammoniacum D. and characterised by employing UV–visible spectroscopy, Fourier transform infrared spectroscopy and X‐ray diffraction techniques. Transmission electron microscopy and field emission scanning electron microscopy were applied to investigate the morphological structure of the bio‐synthesised SNPs. The antimicrobial activity of SNPs was studied against Gram positive (Bacillus cereus and Staphylococcus aureus) and Gram‐negative (Escherichia coli and Salmonella typhimurium) bacteria by employing the disk diffusion agar process. An extremely antimicrobial effect was observed for SNPs. Utilising D. ammoniacum D. as a mediator for the synthesis of SNPs helped to save time and cost. [ABSTRACT FROM AUTHOR]

Several per-O-acetyl and per-O-benzoyl glycosyl thiocarbamides were synthesized by the interaction of glycosyl isothiocyanates and o-phenylene diamine. The identities of these newly synthesized compounds were established on the basis of usual chemical transformations, IR, ¹H NMR, 13C NMR and Mass spectral studies. All the synthesized compounds have been evaluated for their antibacterial and antifungal activity against different bacteria and fungi by agar diffusion method. [ABSTRACT FROM AUTHOR]

Scientists are indeed fascinated by the pharmacologically important chemicals found in medicinal plants. Citrus fruits possess several curing agents for the prevention of diseases. Therefore, experiments were carried out to test the antibacterial activity of methanolic extracts of peels from various locally available citrus fruits such as citron ( Citrus medica ), satkora ( Citrus macroptera ) and adajamir ( Citrus assamensis ) against Bacillus spp. and E. coli using the disc diffusion method. Different physicochemical characteristics of fruit juice were also determined. Methanolic extract of satkora peel had the highest antibacterial activity of 2.2 and 2.6 cm while adajamir had the lowest antibacterial activity of 1.7 and 2.1 cm as ZOI against Bacillus spp. and E. coli , respectively. In the case of pH and total soluble solids (TSS), the three citrus varieties showed a small variation where satkora showed the highest total phenolic content (TPC), vitamin C content, and antioxidant activity than the others. Citrus fruits can be exploited as antibacterial and antioxidant ingredients in food and nutraceuticals, according to the findings of this study., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s).)

Abstract: Lippia alba (Miller) N.E. Brown is an aromatic herb that occurs in practically all regions of Brazil and has a large importance in Brazilian folk medicine. This species is characterized by a variability in morphology and in the chemical composition of the essential oil. The present work focused on the ethnopharmacological investigation of Lippia alba, locally known as “erva-cidreira” and Lippia alba f. intermedia, known as “carmelitana”. In addition, the chemical composition and antimicrobial activity of their essential oils was investigated in order to correlate to their traditional uses. The ethnopharmacological study showed a good agreement of the major use (MUA) of Lippia alba (MUA=92.0%) and to a lesser extent, for Lippia alba f. intermedia (MUA=66.7%), as sedatives. The analyses of the essential oils allowed the identification of Lippia alba as a myrcene–citral chemotype (15% and 37.1%, respectively) and Lippia alba f. intermedia as a citral chemotype (22.1%). The essential oils of both species were active against all microorganisms assayed (bacteria and fungi) by the drop test, with inhibition halos ranging from 1.1 to 5.0cm, probably due to the high content of oxygenated monoterpenes (51.0% and 40.1%, respectively), specially represented by aldehydes and alcohols. The chemical and pharmacological data of Lippia alba are in agreement with the ethnobotanical survey. [Copyright &y& Elsevier]

• Diazinecarboxylic acids exhibit antimicrobial properties. • The biological properties of diazinecarboxylic acids depend on the distribution of the electron charge in the molecule. • The position of heteroatoms in the aromatic ring affects the thermal stability of chemical compounds. Diazinecarboxylic acids (pyridazine-3-carboxylic, pyridazine-4-carboxylic, pyrimidine-2-carboxylic, pyrimidine-4-carboxylic, pyrimidine-5-carboxylic and pyrazine-2-carboxylic acids) were characterized by means of spectroscopic (FT-Raman, FTIR, UV, 1HNMR, 13CNMR) and thermogravimetric analysis as well as antimicrobial and cytotoxic tests. The structures of diazinecarboxylic acids were calculated by the DFT method (B3LYP/6-311G(d, p). For the most stable conformers, the energy of HOMO and LUMO molecular orbitals, the geometric (HOMA, GEO, EN, I6) and magnetic (NICS) aromaticity indices, NBO electronic charge distribution, sEDA and pEDA indexes, Wiberg Bond Order, Wiberg Index and theoretical IR and NMR spectra have been calculated. The energies of protonating and deprotonating acids were also calculated. The effect of the nitrogen heteroatom position in the aromatic ring in relation to the position of the carboxyl group on the electronic charge distribution, thermal stability, antimicrobial and cytotoxicity activities of the examined acids was determined. Antimicrobial activity of tested acids against of Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Candida albicans was calculated based on MTT colorimetric assay (MCA). The cytotocic effect of diazynecarboxylic acids was examined in A375 melanoma cell line and DLD-1 cell line. A biplot analysis was performed in order to determine the correlations between selected parameters of the tested compounds and relative cell viability of E. coli, B. subtilis, P. aeruginosa, C. albicans , A375 and DLD-1 cell lines. Thermal behaviour of all investigated carboxylic acids was investigated using thermogravimetry (TG) and differential scanning calorimetry (DSC) techniques in flowing air atmosphere. All compounds are stable in room temperature. [ABSTRACT FROM AUTHOR]

Açaí seed extracts are reported for containing polyphenols with pharmacological properties against inflammation, hypertension, and metabolic syndrome. However, presently, those seeds accumulate as waste, causing environmental problems. Therefore, we aimed to characterize the polyphenol profile of açaí seed extracts to investigate its composition and biological effects. Multiple techniques were used for the identification of the extract's metabolites, such as HPLC, mass spectrometry, and mass spectrometry imaging (MALDI-IMS). The extract was majorly composed of B-type and A-type oligomeric procyanidins with a mean degree of polymerization of 11.4 (>3000 Da), formed by catechin and epicatechin as starter and extension subunits, respectively. MALDI-IMS confirmed, for the first time, the presence of A-type procyanidins in the seed's tegument. The extract was not cytotoxic to THP1 (macrophage cell line) and LLC-MK2 (epithelial cell) and, moreover, it efficiently protected macrophages from oxidative stress, which correlated to its high antioxidant capacity, confirmed by DPPH, TEAC and ORAC methods. Additionally, the extract presented antimicrobial activity against gram-positive bacterial strains and Candida albicans. These data indicate the potential use of seed extracts for cosmetic and pharmaceutical formulations. Image 1 • The extract is composed of B- and A-types oligomeric procyanidins (>3000 Da). • MALDI-IMS was used to identify procyanidins in situ for the first time. • Procyanidins were active against gram-positive bacteria and C. albicans. • The extract was not cytotoxic for mammalian cells. • Açaí seed extract has a high antioxidant activity that prevents oxidative stress. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles were prepared by a sol-gel method and characterized by XRD, SEM, TEM and EDX. A series of chitosan and polyvinyl alcohol (Cs/PVA) blend films doped with various concentrations of Zinc oxide nanoparticles (ZnO NPs) were prepared by solution casting method. These samples were characterized by various analytical techniques. XRD patterns of the prepared samples showed increasing in amorphousity of the polymer blend with increasing the content of ZnO NPs in Cs/PVA blend. The FT-IR analysis confirmed the complexation between Cs/PVA blend and ZnO NPs. From the UV–vis results, the optical energy gap was calculated. The TGA analysis displayed that the thermal stability of all the samples improved after the addition of the ZnO NPs. By the tensile universal testing machine, the mechanical properties of the prepared films were determined. The antimicrobial analysis showed that all nanocomposite films exhibited enhanced antimicrobial efficacy as compared to pure Cs/PVA film and it is linearly related to the amount of ZnO nanoparticles in the matrix. The sample containing 10 and 15 wt.% ZnO NPs exhibited the highest thermal stability, mechanical strength, and antibacterial activity. This nanocomposite with excellent thermal stability, tensile and antibacterial properties can be potentially utilized for antimicrobial packaging purposes and can be widely used in medical applications. [ABSTRACT FROM AUTHOR]

Ceramic-metal (CaO·Al 2 O 3 -Al and CaO·Al 2 O 3 -Ag) compounds were prepared by mechanical milling and consolidated through an in-situ sintering process. The aim of this work is to study the effects of the Al and Ag particles to ceramic-base compound, primarily in the microstructure, and its mechanical and antimicrobial properties. Chemical systems with a 1:1 M ratio between CaCO 3 and Al 2 O 3 powder were formed, with the addition of 10 wt% Al or 10 wt% Ag, respectively. The compound material that consolidated were microstructurally characterized through X-ray diffraction, scanning electron microscopy, optic microscopy, and X-ray computed tomography. In addition, the hardness, the fracture toughness, the transversal elastic modulus, and the antimicrobial property were evaluated. The results of X-ray diffraction identified the formation of the calcium aluminate phases, such as CaO·6Al 2 O 3 (hibonite:CA6), CaO·2Al 2 O 3 (grossite:CA2), and CaO·Al 2 O 3 (krotite:CA); as well as Al and Ag were identified in its respective system. In addition, the mechanical properties show changes compared to the reference material that was synthesized under the same conditions and, finally, these materials also have an antimicrobial effect, against the Staphylococcus bacterium that is common in the oral cavity, when studied in synthetic saliva., (Copyright © 2019 Elsevier Ltd. All rights reserved.)