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Antimicrobial resistance constitutes a topical subject and it is one of the major threats to public health. According to statistics, the incidence of multidrug-resistant microorganisms, such as bacteria, fungi and protozoa has increased in the last decades and it continues to spread. Therefore, the development of novel antimicrobial agents to combat drug-resistant infections is very important, among other research directions in this field. Quinoline ring is a very interesting structure for researchers because of its diverse biological properties (antimicrobial, anticancer, anticonvulsant, antiinflamatory and cardiovascular). On the other hand several studies showed good antibacterial activity (including anti-Pseudomonas effects) and antifungal properties of rutin or vegetal species with a high flavonoids (especially rutin) concentration. Based on the above considerations, eight novel rutin derivatives carrying 4- and 8-aminoquinoline moiety were designed, synthesized and characterized by FTIR, 1H NMR and elemental analysis. All compounds were evaluated for their in vitro antimicrobial activities against representative Gram-positive, Gram-negative and fungal pathogens. The results indicated that all rutin derivatives exhibited good antibacterial activities, similar to ciprofloxacin.

The present study focuses on the chemical and biological analysis of the ethanolic 70% v/v extracts obtained from Amorpha fruticosa leaves, branches and fruits. The total phenolic content determined by Folin-Ciocalteu method was the highest in leaves extract (159.5 mg/g). The HPLC-MS analysis indicated the presence of ferulic acid, luteolin and rutoside in all three extracts. The antioxidant activity was tested by the DPPH method and the results indicated a good scavenging activity (EC50 = 18.8 ± 0.2 µg/mL) for the fruit extract, followed by leaf extract (EC50 = 38.03 ± 0.75 µg/mL) and branch extract (EC50 = 221.16 ± 1.7 µg/mL). The antimicrobial activity evaluated by agar disc diffusion method indicated the inhibition of growth for Staphylococcus aureus and Sarcina lutea for all samples.

Natural compounds have been used as wound-healing promoters and are also present in today's clinical proceedings. In this research, different natural active components such as propolis, Manuka honey, insulin, L-arginine, and Calendula officinalis infusion were included into hyaluronic acid/poly(ethylene)oxide-based electrospun nanofiber membranes to design innovative wound-dressing biomaterials. Morphology and average fiber diameter were analyzed by scanning electron microscopy. Chemical composition was proved by Fourier transform infrared spectroscopy, which indicated successful incorporation of the active components. The nanofiber membranes with propolis and Calendula officinalis showed best antioxidant activity, cytocompatibility, and antimicrobial properties against pathogen strains Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa and had an average diameter of 217 ± 19 nm with smooth surface aspect. Water vapor transmission rate was in agreement with the range suitable for preventing infections or wound dehydration (~5000 g/m2 24 h). Therefore, the developed hyaluronic acid/poly(ethylene)oxide nanofibers with additional natural components showed favorable features for clinical use as wound dressings. ispartof: POLYMERS vol:13 issue:8 ispartof: location:Switzerland status: published

Glibenclamide and lipoic acid are two drugs frequently recommended for the management of diabetes mellitus, and so, the development of a new formulation containing both substances has a great benefit in terms of efficiency and compliance, acting also as a multi-target drug system. Accordingly, the aim of this study was the formulation and physicochemicalcharacterization of new polymeric systems based on chitosan (CS) in whose matrix were encapsulated glibenclamide (Gly) and lipoic acid (LA). The polymeric systems were prepared as microparticles (CS&ndash, Gly, CS&ndash, LA, and CS&ndash, Gly&ndash, LA) through ionic gelation method, using pentasodium tripolyphosphate (TPP) as crosslinking agent. The polymeric systems obtained were characterized in terms of particle size and morphology, IR spectroscopy, entrapment efficiency and drug loading, swelling degree, and therelease of the active substances from the chitosan matrix. The polymeric systems obtained were stable systems, the presence of glibenclamide and lipoic acid into the polymer matrix were proved by IR spectroscopy. The entrapment efficiency was 94.66% for Gly and 39.68% for LA. The developed polymeric systems proved a favorable swelling degree and drug release profile, the percentage of release being 88.68% for LA and 75.17% for Gly from CS&ndash, LA systems.

Synthesis of silver nanoparticles (AgNPs) by plants is a simple, non-toxic and eco-friendly method. The purpose of this study was to develop a method for obtaining silver nanoparticles with biological properties. For reducing the silver ions, an extract of Tilia cordata (linden) flowers was used. Some parameters were investigated to optimize the synthesis method. Thus, the conditions of reaction were varied, such as pH, concentration of silver salt, different ratio of plant extract and silver salt, temperature and stirring time. The formation of nanoparticles was demonstrated by Ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectra (FTIR), Transmission electron microscopy (TEM), Energy dispersive X-ray analysis (EDX), Photon correlation spectroscopy (PCS), Electrophoretic light scattering (ELS). In order to determine possible biological applications, we tested the antimicrobial and the antioxidant activities. The results demonstrated that linden flowers could be used to obtain silver nanoparticles with an important potential in the development of some therapeutic agents.

Cationic amphiphilic dextran derivatives with a long alkyl group attached to the reductive end of the polysaccharide chain and quaternary ammonium groups attached as pendent groups to the main dextran backbone were synthesized and tested for their antimicrobial properties against several bacteria and fungi strains. Dependence of antimicrobial activity on both polymer chemical composition (dextran molar mass, length of end alkyl group and chemical structure of ammonium groups) and type of microbes was highlighted by disc-diffusion method (diameter of inhibition zone) and broth microdilution method (minimum inhibitory concentrations). Polymers had antimicrobial activity for all strains studied, except for Pseudomonas aeruginosa ATCC 27853. The best activity against Staphylococcus aureus (Minimun Inhibitory Concentration 60μg/mL) was provided by polymers obtained from dextran with lower molecular mass (Mn=4500), C12H25 or C18H37 end groups, and N,N-dimethyl-N-benzylammonium pendent groups.

New amphiphilic dextran esters were obtained by polysaccharide functionalization with different substituted 1,2,3-triazoles-4-carboxylic acid via in situ activation with N, N′-carbonyldiimidazole. Nitrogen-containing heterocyclic derivatives were achieved by copper(I)-catalyzed cycloaddition reaction between organic azides and ethyl propiolate. Structural characteristics of the compounds were studied by elemental analysis, Fourier transform infrared and nuclear magnetic resonance spectroscopy (1H and 13C‐NMR). Thermogravimetric analysis, differential scanning calorimetry and wide-angle X-ray diffraction were used for esters characterization. Properties of polymeric self-associates, formed in aqueous solution, were studied by dynamic light scattering and transmission electron microscopy. The critical aggregation concentration values for dextran esters, determined by fluorescence spectroscopy, were in the range of 4.1-9.5 mg/dL. Antimicrobial activity, investigated for some of the polymers by disc-diffusion method, pointed out that polysaccharide esters were active.

Despite the advantages presented by synthetic polymers such as strength and durability, the lack of biodegradability associated with the persistence in the environment for a long time turned the attention of researchers to natural polymers. Being biodegradable, biopolymers proved to be extremely beneficial to the environment. At present, they represent an important class of materials with applications in all economic sectors, but also in medicine. They find applications as absorbers, cosmetics, controlled drug delivery, tissue engineering, etc. Chitosan is one of the natural polymers which raised a strong interest for researchers due to some exceptional properties such as biodegradability, biocompatibility, nontoxicity, non-antigenicity, low-cost and numerous pharmacological properties as antimicrobial, antitumor, antioxidant, antidiabetic, immunoenhancing. In addition to this, the free amino and hydroxyl groups make it susceptible to a series of structural modulations, obtaining some derivatives with different biomedical applications. This review approaches the physico-chemical and pharmacological properties of chitosan and its derivatives, focusing on the antimicrobial potential including mechanism of action, factors that influence the antimicrobial activity and the activity against resistant strains, topics of great interest in the context of the concern raised by the available therapeutic options for infections, especially with resistant strains.

Chitosan is a non-toxic, biocompatible, biodegradable natural cationic polymer known for its low imunogenicity, antimicrobial, antioxidant effects and wound-healing activity. To improve its therapeutic potential, new chitosan-sulfonamide derivatives have been designed to develop new wound dressing biomaterials. The structural, morphological and physico-chemical properties of synthesized chitosan derivatives were analyzed by FT-IR, (1)H NMR spectroscopy, scanning electron microscopy, swelling ability and porosity. Antimicrobial, in vivo testing and biodegradation behavior have been also performed. The chitosan derivative membranes showed improved swelling and biodegradation rate, which are important characteristics required for the wound healing process. The antimicrobial assay evidenced that chitosan-based sulfadiazine, sulfadimethoxine and sulfamethoxazole derivatives were the most active. The MTT assay showed that some of chitosan derivatives are nontoxic. Furthermore, the in vivo study on burn wound model induced in Wistar rats demonstrated an improved healing effect and enhanced epithelialization of chitosan-sulfonamide derivatives compared to neat chitosan. The obtained results strongly recommend the use of some of the newly developed chitosan derivatives as antimicrobial wound dressing biomaterials.

A smectogen liquid crystal based on benzoate units has been synthesized and structurally characterized by FTIR and 1H NMR spectroscopy. Besides, its structure and supramolecular arrangement in the crystalline state was demonstrated by single crystal X-ray diffraction measurements. The thermotropic behaviour, monitored by differential scanning calorimetry and polarized light microscopy, consists in the formation of an enantiotropic smectic mesophase with a direct first order transition from the isotropic to smectic mesophase, and with its thermal stability range superposed on human body temperature. The smectogen liquid crystal has moderate wettability – suitable for biocompatible materials and presents good antipathogenic activity against gram positive and gram negative bacteria and fungus. All these properties recommend the understudied liquid crystal to be used in biochemical and biological applications.

In the past many research studies have focused on the thiazolidine-4-one scaffold, due to the important biological effects associated with its heterocycle. This scaffold is present in the structure of many synthetic compounds, which showed significant biological effects such as antimicrobial, antifungal, antioxidant, anti-inflammatory, analgesic, antidiabetic effects. It was also identified in natural compounds, such as actithiazic acid, isolated from Streptomyces strains. Starting from this scaffold new xanthine derivatives have been synthetized and evaluated for their antibacterial and antifungal effects. The antibacterial action was investigated against Gram positive (Staphyloccoccus aureus ATCC 25923, Sarcina lutea ATCC 9341) and Gram negative (Escherichia coli ATCC 25922) bacterial strains. The antifungal potential was investigated against Candida spp. (Candida albicans ATCC 10231, Candida glabrata ATCC MYA 2950, Candida parapsilosis ATCC 22019). In order to improve the antimicrobial activity, the most active xanthine derivatives with thiazolidine-4-one scaffold (XTDs: 6c, 6e, 6f, 6k) were included in a chitosan based polymeric matrix (CS). The developed polymeric systems (CS-XTDs) were characterized in terms of morphological (aspect, particle size), physic-chemical properties (swelling degree), antibacterial and antifungal activities, toxicity, and biological functions (bioactive compounds loading, entrapment efficiency). The presence of xanthine-thiazolidine-4-one derivatives into the chitosan matrix was confirmed using Fourier transform infrared (FT-IR) analysis. The size of developed polymeric systems, CS-XTDs, ranged between 614 &micro, m and 855 &micro, m, in a dry state. The XTDs were encapsulated into the chitosan matrix with very good loading efficiency, the highest entrapment efficiency being recorded for CS-6k, which ranged between 87.86 &plusmn, 1.25% and 93.91 &plusmn, 1.41%, depending of the concentration of 6k. The CS-XTDs systems showed an improved antimicrobial effect with respect to the corresponding XTDs. Good results were obtained for CS-6f, for which the effects on Staphylococcus aureus ATCC 25923 (21.2 &plusmn, 0.43 mm) and Sarcina lutea ATCC 9341 (25.1 &plusmn, 0.28 mm) were comparable with those of ciprofloxacin (25.1 &plusmn, 0.08 mm/25.0 &plusmn, 0.1 mm), which were used as the control. The CS-6f showed a notable antifungal effect, especially on Candida parapsilosis ATCC 22019 (18.4 &plusmn, 0.42 mm), the effect being comparable to those of nystatin (20.1 &plusmn, 0.09 mm), used as the control. Based on the obtained results these polymeric systems, consisting of thiazolidine-4-one derivatives loaded with chitosan microparticles, could have important applications in the food field as multifunctional (antimicrobial, antifungal, antioxidant) packaging materials.

The use of antioxidants and antibacterials in food industry has become increasingly necessary to ensure the high quality of food. Grape pomace is the main by-product of winemaking industry that concentrates bioactive metabolites with more studied antioxidant activity and possible antibacterial activity. The grape pomace contains fragmented skin, broken cells, pulp remains, stalks and seeds with high amount of phenolic compounds due to their poor extraction during the winemaking process. Anthocyanins, catechins, flavonol glycosides, phenolic acids, alcohols and stilbenes have been identified among the compounds present in grape pomace. In this study, antibacterial activity against different pathogens (Escherichia coli ATCC 25922, Candida albicansATCC 90028, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923) was evaluated and the relation with polyphenols content and antioxidant activity of grape pomace from selected grapes from Iaşi vineyard was studied. The grape pomace samples were obtained after the fermentation process from the 2017 harvest of Sauvignon Blanc, Traminer, Busuioacă de Bohotin, Cabernet Sauvignon, Merlot, Fetească Neagră and Fetească Regală grape varieties. The antioxidant properties were evaluated using the DPPH method, FRAP assay and Folin Ciocalteu method. The content of resveratrol was quantified using an HPLC method. Samples with antioxidant activity showed the highest phenolics content. This study reveals that grape pomace is a potential source of natural antioxidant agents. The pomace extracts were tested to establish the effects on Gram-positive and Gram-negative bacteria. The analysed samples exhibited insignificant antibacterial activity and the method requires optimization. Grape marc represents an important source of resveratrol and other bioactive compounds that could be a valuable source of antioxidants for further utilization in food and pharmaceutical industry.

The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190% and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-sulfamerazine (CS-S5) which was 8.3 times more active than chitosan related to DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging ability. This compound showed also a good ferric reducing power and improved total antioxidant capacity.

The purpose of this study was to investigate the influence of hydroxypropyl-β-cyclodextrin on diosmin, substance from the flavones category with important pharmacological properties. We carried out solubility studies, calculating the solubility constant of the complex formed between diosmin and hydroxypropyl-cyclodextrin at various temperatures (20, 25 and 37 0 C) and in the presence of increasing cyclodextrin concentrations. AL type curves were obtained which suggest the formation of an inclusion compound on a 1:1 molar ratio and the solubility constants had values between 370 and 453 M -1 . Knowing that between diosmin, hydroxypropyl-cyclodextrin and the used solvent, thermodynamic interactions occur, we investigated the influence of these interactions on several thermodynamic parameters such as Gibbs free energy change, free energy change, enthalpy change and entropy change. The calculated values showed that the reaction is positively influenced by the cyclodextrin’s concentration increment and the temperature, the process being spontaneously. Next, inclusion compounds were obtained by co-evaporation and co-precipitation, and their structures were confirmed by FTIR and MS analysis. The complexes were tested in vitro compared with the parent substances, the results indicating improved antioxidant and antimicrobial activities. Moreover, the dissolution of diosmin increased in mediums similar to physiological conditions (simulated gastric and intestinal).

New biocompatible amphiphilic block copolymers were prepared using two natural compounds as starting materials, a polysaccharide (dextran) and a bile acid (deoxycholic acid). The copolymers were synthesized by dipolar 1,3-cycloaddition reaction between dextran with azide end groups and deoxycholic acid - oligo(ethylene glycol)s polyester with propargyl end groups. Different copolymer composition were obtained by variation of molecular weights of dextran (Mn 4.5, 8, 15 kDa) and polyester (Mn 2–6 kDa), as well as the length of oligo(ethylene glycol) (2–4 ethylenglycol units) used for polyester synthesis. These copolymers can for micelle like aggregates in aqueous medium with nanometric size (50–600 nm) and spherical form, as assessed by light scattering, atomic force microscopy and transmission electron microscopy. Encapsulation of the hydrophobic drug curcumin in micelles could increase 68,181 times its water solubility, and curcumin release from micelles was slow and with reduced burst effect.

This paper presents the synthesis and characterization of gellan gum derivatives containing quaternary ammonium groups, with the purpose of obtaining particulate controlled release systems for ciprofloxacin. Quaternized gellan derivatives were synthesized by grafting N-(3-chloro-2-hydroxypropyl)-trimethyl ammonium chloride onto gellan primary hydroxyl groups by nucleophilic substitution, in the presence of alkali, under specific reaction conditions using various gellan/N-(3-chloro-2-hydroxypropyl)-trimethyl ammonium chloride molar ratios. Degree of quaternization was determined by 1 H NMR spectroscopy and AgNO 3 conductometric titration. Thermal behavior was investigated for all materials by thermogravimetric analysis. A study of the degree of quaternization and effect of the reaction conditions upon activation energy of quaternized gellan derivatives for the main degradation step by applying the Kissinger method at four heating rates is also reported. The novelty that this work brings refers to obtaining quaternized gellan and chitosan based particles with retention of quaternary ammonium moieties' antibacterial activity. In vitro transdermal release tests of ciprofloxacin from loaded particles were carried out on rat skin in isotonic phosphate buffer solution (pH = 7.43). Ciprofloxacin was released up to 24 h, confirming quaternized gellan–chitosan particles' potential as controlled release systems for topical dermal applications.

Herein we report a feasible study concerning the design, synthesis, and in vitro antimicrobial activity of some novel homodrimane sesquiterpenoids with diazine skeleton. The reaction pathway is efficient and straight, involving the direct N-acylation of diazine with homodrimane sesquiterpenoids bearing acyl chlorides or organic acids functionality. A reliable explication and a feasible reaction mechanism for the obtained compounds are presented. The in vitro antimicrobial activity of the homodrimane sesquiterpenoids with and without diazine skeleton has been evaluated. All the tested compounds have an excellent antibacterial activity against Gram-positive strains S. aureus and B. cereus. SAR correlations concerning antimicrobial activity are reported. The design, synthesis, and in vitro antimicrobial activity of some novel homodrimane sesquiterpenoids with diazine skeleton are described. Antimicrobial tests prove that some homodrimane sesquiterpenoids have an excellent biological activity.

A comprehensive study concerning synthesis, structure and biological activity of new pyridazine–fluorine ( PYF ) derivatives is presented. The first synthesis of PYF derivatives in phase-transfer catalysis (PTC) under microwave (MW) and conventional thermal heating (TH) is reported. Under MW irradiation the consumed energy decreases considerably, the amount of used solvent in liquid phase is at least five-fold less comparative with conventional TH, while PTC did not use solvents. Consequently these reactions could be considered environmentally friendly. Also, the reaction time decrease substantially and, in some cases, the yields are higher. A feasible explanation for MW efficiency is presented. Regiochemistry and chorochemistry involved in these reactions are also discussed; the reactions are regioselective and chorospecific or choroselective, respectively. Ten new pyridazine–fluorine cycloadducts are obtained. The in vitro antibacterial and antifungal activities of the PYF compounds were tested. Introduction of a trifluoromethyl moiety on the pyridazine skeleton is leading to an increasing of the antimicrobial activity. Structure–activity correlationships have been done.

This study was carried out to investigate the chemical composition, the antioxidant and antimicrobial effects of the essential oils of Pinus cembra L. needles and twigs. The chemical composition was analyzed using both GC and GC-MS techniques. ?-Pinene (69.14%) was the major constituent of the needle essential oil while the twig essential oil was characterized by a high content of limonene+ ?-phellandrene (40.97%) and ?-pinene (24.94%). The needle and twig essential oils showed weak DPPH radical scavenging effects (EC50=19.93?0.75 and EC50=18.66?0.70 mg ml-1, respectively). In antimicrobial assays, both essential oils showed high activity against Sarcina lutea and Staphylococcus aureus and no activity against Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The needle and twig essential oils had similar antimicrobial effects against Sarcina lutea with MIC and MBC values of 0.12 and 0.24 mg ml-1, respectively. The twig essential oil (MIC=1.95 mg ml-1, MBC=3.9 mg ml-1) was more active against Staphylococcus aureus than the needle essential oil (MIC=3.9 mg ml-1, MBC=15.62 mg ml-1) and also exhibited a moderate activity against Candida albicans (MIC=7.81 mg ml-1, MFC=15.62 mg ml-1).

Acute poisonings represent a common cause of morbidity and mortality worldwide. The prognostic utility of the transthoracic echocardiography (TTE) parameters combined with brain natriuretic peptide (BNP) in acute poisoning with different xenobiotics, upon admission in the hospital was not evaluated. This prospective observational cohort study included 229 acutely poisoned non-diabetic adults, with a median age of 44 years (range 18-90 years), 50.7% women, with an in-hospital mortality rate of 8.7%. Univariate logistic regression analysis showed that age, the left ventricle kinetic abnormalities, the E wave deceleration time (EDT) and BNP correlated significantly with mortality in acutely poisoned patients. Multivariate logistic regression showed that only EDT [odds ratio (OR) 3.44, 95% confidence interval (CI) 1.54-7.69, p 0.003], BNP (OR 1.61, 95% CI 1.02-2.55, p 0.04), and age (OR 2.66, 95%CI 1.23-5.76, p 0.013) are predictive for mortality. The receiver operating characteristic (ROC) analysis proved EDT [area under the ROC curve (AUC), 0.85; CI, 0.76-0.94; p 0.001], BNP (AUC, 0.83; CI, 0.75-0.91; p 0.001) and age (AUC, 0.82; CI, 0.74-0.90; p 0.001) as indicators for fatalities. In hospitalized patients acutely intoxicated with undifferentiated poisons, EDT as a parameter of left ventricle diastolic function and BNP are useful to early predict mortality. This article is protected by copyright. All rights reserved.

Acute exposure to systemic poisons represents an important challenge in clinical toxicology. We aimed to analyze the potential role of cardiac biomarkers, routine laboratory tests, and clinical scores as morbidity and in-hospital mortality predictors in patients intoxicated with various systemic poisons. We conducted a prospective study on adults acutely exposed to systemic poisons. We determined the PSS, Glasgow Coma Scale (GCS), and we performed electrocardiogram, laboratory tests, lactate and cardiac biomarkers (which were reassessed 4 h, respectively 6 h later). Of 120 patients included, 45% developed complications, 19.2% had a poor outcome, and 5% died. Multivariate logistic regression sustained lactate (odds ratio (OR) 1.58; confidence interval (CI) 95%: 0.97–2.59; p 0.066), MB isoenzyme of creatine kinase (6h-CKMB; OR 1.08; CI 95%: 1.02–1.16; p 0.018) as predictors for a poor outcome. A GCS < 10 (OR 0.113; CI 95%: 0.019–0.658; p 0.015) and 4h-lactate (OR 4.87; CI 95%: 0.79–29.82; p 0.087) predicted mortality after systemic poisons exposure. Receiver operating characteristic analysis showed that brain natriuretic peptide (area under the curve (AUC), 0.96; CI 95%: 0.92–0.99; p < 0.001), lactate (AUC, 0.91; CI 95%: 0.85–0.97; p < 0.001), and 6h-CKMB have good discriminatory capacity for predicting a poor outcome. In conclusion, these biomarkers, lactate, and GCS can be used to predict morbidity and mortality after systemic poisons exposure.

Background l-Arginine is a semi-essential aminoacid with important role in regulation of physiological processes in humans. It serves as precursor for the synthesis of proteins and is also substrate for different enzymes such as nitric oxide synthase. This amino-acid act as free radical scavenger, inhibits the activity of pro-oxidant enzymes and thus acts as an antioxidant and has also bactericidal effect against a broad spectrum of bacteria. Results New thiazolidine-4-one derivatives of nitro-l-arginine methyl ester (NO2-Arg-OMe) have been synthesized and biologically evaluated in terms of antioxidant and antibacterial/antifungal activity. The structures of the synthesized compounds were confirmed by 1H, 13C NMR, Mass and IR spectral data. The antioxidant potential was investigated using in vitro methods based on ferric/phosphomolybdenum reducing antioxidant power and DPPH/ABTS radical scavenging assay. The antibacterial effect was investigated against Gram positive (Staphylococcus aureus ATCC 25923, Sarcina lutea ATCC 9341) and Gram negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) bacterial strains. The antifungal activity was also investigated against Candida spp. (Candida albicans ATCC 10231, Candida glabrata ATCC MYA 2950, Candida parapsilosis ATCC 22019). Conclusions Synthesized compounds showed a good antioxidant activity in comparison with the NO2-Arg-OMe. The antimicrobial results support the selectivity of tested compounds especially on P. aeruginosa as bacterial strain and C. parapsilosis as fungal strain. The most proper compounds were 6g (R = 3-OCH3) and 6h (R = 2-OCH3) which showed a high free radical (DPPH, ABTS) scavenging ability and 6j (R = 2-NO2) that was the most active on both bacterial and fungal strains and also it showed the highest ABTS radical scavenging ability.Graphical abstract1: ethyl 3-aminopropionate hydrochloride, 2a–j: aromatic aldehydes, 3: thioglycolic acid, 4a–j: thiazolidine-propionic acid derivatives , 5: Nω-nitro-L-arginine methyl ester hydrochloride, 6a–j: thiazolidine-propionyl-nitro-L-arginine methyl ester derivatives

Use of antibiotics in food animals may contribute to development and spread of resistant organisms, particularly so in some countries. The aim of this study was two-fold; first, to establish the prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in chicken production in a region within Romania. Second, to study the relatedness of ESBL-producing E. coli isolates recovered from broilers, abattoir workers where the chickens were slaughtered and from the human clinical specimens from two regional hospitals. The results indicated a very high (69%) rate of carriage of ESBL and AmpC-producing E. coli in chickens with 36% CTX-M producers. Sequencing showed that chickens in Romania have the highest worldwide prevalence (53%) of blaCTX-M-15 reported in poultry E. coli isolates. The majority (53%) of the extended-spectrum cephalosporin-resistant E. coli carried plasmid-mediated blaampC genes, mostly blaCMY-2 type, one of the highest prevalences reported in Europe. The predominant CTX-M type found in the human clinical E. coli isolates was blaCTX-M-15 and most isolates coharbored blaOXA-1, blaTEM, and aac(6')-ib-cr. The majority (60%) of the human clinical isolates belonged to the pandemic virulent clone B2-ST131. The clonal relationship between broiler and the human CTX-M-producing E. coli isolates was assessed by macrorestriction pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), which indicated strain diversity with no common STs found between human and poultry isolates. Moreover, IncI1 was the most prevalent replicon found in broiler ESBL-producing E. coli isolates and also in transconjugants, indicating that plasmids and not clonal spread may play a role in the transfer of blaCTX-M genes. This study identifies a high prevalence of ESBL-producing E. coli from broiler chickens in Romania with a high occurrence incidence of blaCTX-M-15, which reflects the main ESBL type found in human E. coli infections in this country.

Five cinnamic acid derivatives [cinnamic acid, 2,3-dibromo-3-phenyl-propanoic acid, 2,3-dibromo-3-(3-bromophenyl)-propanoic acid, 2,3-dibromo-3-(4-hydroxy-3-methoxyphenyl)-propanoic acid, and 2,3-dibromo-3-(3-bromo-4-hydroxy-5-methoxyphenyl)-propanoic acid] were found to be active against Staphylococcus aureus ATCC 25923, and their minimal bactericidal concentrations were determined (100 µg/mL). The first step in assessing their toxicological potential was the phytotoxicity and genotoxicity evaluation on Triticum aestivum. Wheat seeds were exposed to solutions of the tested compounds (100 µg/mL) for 24 and 48 h. The development of roots and seedlings, germination percentage, mitotic index, chromosomal aberrations, and total polyphenol content were analyzed. The substances caused in most experimental cases a slight inhibition in the growth of the tested plantlets in comparison to the control, with the exception of 2,3-dibromo-3-(3-bromo-4-hydroxy-5-methoxyphenyl)-propanoic acid (48 h of exposure). All compounds inhibited the germination process and mitotic activity. No aberrant metaphases were generated, but abnormal anatelophases appeared, and 4 types of chromosomal aberrations were identified: chromosome bridges, chromosome fragments, micronuclei, and multipolar anatelophases. Wheat plantlet metabolism was also affected; the total polyphenol content decreased in the treated plantlets.

Herein we report a feasible study concerning the design, syntheses and in vitro antimicrobial and antitumoral activities of some novel compounds with dihydroxyacetophenone (DA) moiety. An efficient and general method for the preparation of diazine with dihydroxyacetophenone (DDA) skeleton under conventional thermal heating (TH), microwave (MW) and ultrasounds (US) irradiation is presented. Antimicrobial and antitumoral tests prove that some dihydroxyacetophenone compounds (the brominated derivatives BrDA 3) have a significant biological activity. It is also to be pointed out that, basically all the dihydroxyacetophenone derivatives proved to have a powerful antibacterial activity against drug resistant Gram-negative strain Pseudomonas aeruginosa ATCC 27853. Of particular interest could be the excellent antibacterial activity of our dihydroxyacetophenone compounds against drug resistant Gram-negative strain Pseudomonas aeruginosa.

In the last decades resistance and reduced susceptibility to antimicrobial agents has become a major therapeutic problem. Both Staphylococcus aureus and Staphylococcus epidermidis are frequently resistant to methilpenicillins and derivatives, including methicillin, oxacillin and nafcillin. One of the antibacterial agents which exhibits a spectrum of activity against Gram-positive bacteria is azithromycin, a macrolide with properties closely resemble those of erytromycin. Azithromycin susceptibility was obtained for 84.3% of S. aureus and 87.4% of S. epidermidis respectively. Erythromycin resistance was more prevalent in S. aureus strains (20.5%) than in coagulase-negative staphylococci (15%). Oxacillin resistance has low and similar resistance rates for staphylococci (between 1.6-1.8%). Meropenem had excellent activity: all strains were susceptible. The results of surveillance of resistance has not been extensive.