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An efficient one-pot route leading to bis-indolizine symmetric compounds has been developed via a new approach from the dipyridinium heterocyclic compound, reactive halogenated derivative, and activated alkyne through biocatalysis. A set of local plants was evaluated for its catalytic potential in “one-pot” biocatalysis of these valuable fluorescent compound synthesis reactions. Most of these biocatalysts containing enzymes from the oxidoreductase class (peroxidase: 0.56–1.08 mmol purpurogallin‧g−1 fresh weight‧min−1, polyphenol oxidase (PPO) : 27.19–48.95 PPO units‧mg tissue−1, CAT: 3.27–21.71 µmol O2‧g−1 fresh weight‧min−1), were used as green catalysts in the multi-component cycloaddition reaction, in an aqueous buffer solution, for the production of bis-indolizine compounds in moderate to excellent yields (45–85%). The horseradish root (Armoracia rusticana) has been selected as the most promising biocatalyst source among the evaluated plants, and the obtained yields were greater than in the conventional synthesis method. The structures of indolizine derivatives were confirmed by nuclear magnetic resonance spectra, elemental analyses, as well as Fourier transform-infrared spectra. The cytotoxicity of the latter obtained indolizine compounds on the growth of the model microorganism, Saccharomyces cerevisiae MIUG 3.6 yeast strain, was also evaluated. Various parameters (number of generations, growth rate, generation time, dry matter yield, the degree of the budding yeast cells, and the degree of yeast autolysis, fermentation intensity), which describe the yeast growth, suggest that the nutrient broth supplemented with different concentrations of bis-indolizine compounds (10 and 1 µM) had no toxic effect on the yeast strain growth, under submerged cultivation conditions.

The consumption of pharmaceuticals has increased worldwide and new compounds are continually being introduced in the market. Studies on the occurrence of pharmaceuticals show that the widely used pharmaceuticals acid clofibric are present in relevant concentrations in the environment. This molecule is recognized as highly resistant to biodegradation (WWTP biomass or bacteria) and has high persistence in the environment. Hence, to date, the elimination of this molecule continues to be a subject of interest. This study employs a viable alternative for micropollutant removal. The aim of the present study was to investigate the potential of selected strain to degrade CLA and their adaptability in multiple cultures with activated sludge. Additionally, the possibility of biostimulation of the activity of microorganisms from the consortium by optimizing their functionality in the biodegradation process of pharmaceutical compound was also examined. The results showed a removal efficiency of CLA of 58.5% when the wet biomass ratio Streptomyces MIUG 4.89: activated sludge was 1:1. This work represents the first study of the ability of multiple cultures Streptomyces MIUG 4.89 and activated sludge to remove this refractory compound. [ABSTRACT FROM AUTHOR]

Laundry detergents are mixtures of chemical compounds commonly used as cleaning agents for clothes and various objects. Their different degree of decomposition and transformation make wastewater to contain a variable proportion of such contaminants. There is a possibility of contamination of the soil, but also of plant crops with detergents, if these insufficiently treated waters are used in irrigation.The aim of this study is to evaluate the degree of phytotoxicity of lavender powder detergent on lettuce (Lactuca sativa L.). The effect of the detergent was highlighted through the germination of seeds and the growth of lettuce seedlings.The use of lettuce as a test plant is recommended by OECD 208 and is a species that can be easily handled in pilot conditions but also in the field. [ABSTRACT FROM AUTHOR]

The specific heat of nano-ferrites modified composites was studied using differential scanning calorimeter (DSC) method in the temperature range of 30 to 150°C. Initially, nano-ferrites were introduced in epoxy systems in order to improve the electromagnetic properties of formed materials. Together with the changes in electromagnetic properties some modifications occur regarding thermal and mechanical properties. The materials were formed by placing 5g or 10g of ferrite into 250g polymer matrix leading to a very low weight ratio of modifying agent. At so low ratios the effect of ferrite presence should be insignificant according to mixing rule. Anyway there is possible to appear some chelation reaction with effects on thermal properties of materials. Three types of epoxy resins had been used as matrix and barium ferrite and strontium ferrite as modifying agents. The thermal analysis was developed on two heatingcooling cycles and the specific heat was evaluated for each segment of the cycle analysis.

Starting with January 2013, all ships greater than 400 tons engaged in international voyages must comply with the Energy Efficiency Design Index (EEDI), and starting with January 2023 also with the Efficiency Existing Ship Index (EEXI), issued by the International Maritime Organization, (IMO). Knowing that, in general, a ship hull is the result of a compromise between the main dimensions imposed by the size of the locks, navigation route depth, port depth, taxes, transport capacity (deadweight, volume), ship equipment (machinery, deck installations, piping systems), hydrostatic performances and last but not least the hydrodynamic performances, from ship hydrodynamics point of view the available approaches are the optimization of the ship size and hull forms or the design of propellers adapted to the ship's wake. The main purpose is to reduce the ship resistance and increase the efficiency of the propulsion system which ultimately leads to a reduction in the power placed on board the ship. For this, there can be used the so-called flow control devices or Energy Saving Devices (ESD hereafter), as hydrofoils or nozzles, to improve the flow parameters entering the propeller disc in order to increase the efficiency of the propulsion system and decreasing the fuel consumption leading to reducing of the carbon and greenhouse gasses emissions. For ballast loading condition the ESD may intersect the free surface, the flow becoming complicated and combining nonlinear, three-dimensional and turbulent phenomena such as the boundary layer on solid surfaces, the horseshoe vortex system developed around junctions and their effects turbulence, and also wave breaking. Therefore, this paper presents the results of the numerical study on the viscous free surface flow around junctions between a hydrofoil mounted on a plate, more precisely the study of the influence of the angle between hydrofoil and plate. It was observed that from a hydrodynamic point of view the angle between hydrofoil and base plate to be less than 15 degrees in respect to the vertical direction on the hydrofoil so that horseshoe vortex to be reduced in intensity and the value of the hydrofoil drag to be minimal. [ABSTRACT FROM AUTHOR]

The aim of this study is the quantitative and qualitative evaluation of the homemade bors microbiota, a microbiota developed after the fermentation of the mixture of cereals, herbs and huste. Bors, a specific product for traditional Romanian gastronomy, is considered a real therapeutic remedy. It is a product rich in organic acids, minerals, vitamins and enzymes, resulting from the fermentation process of bran. The microbiota that helps fermentation generates B vitamins, D vitamin, enzymes, minerals in easily assimilable forms (calcium, magnesium, phosphorus), and vital trace oligoelements for health: selenium, but especially chromium with important benefits in regulating blood sugar and lowering cholesterol. Homemade bors (as grandmother used to do) has many benefits for the body compared to commercial products that may contain preservatives, flavor enhancers and various food additives, which alter its nutritional quality. The objectives of this research were: identification in the literature of studies and researches on this product; identification of conditions and ways of preparation of homemade bors, realization of experimental variants of bors in laboratory conditions: 9 experimental variants and monitoring of their physico-chemical, organoleptic parameters and evaluation of the microbiota developed in each experimental variant. A questionnaire was applied regarding the preparation and consumption of this product. The obtained results showed a quantitative differentiation of the microbiota, of the organoleptic qualities and a variation of the physico-chemical parameters of the bors samples, depending on the quantities of the huste, flour, corn and wheat bran and the water properties used in the work. [ABSTRACT FROM AUTHOR]

BACKGROUND: Anthocyanins were extracted from grape skins by a combination of ethanolic‐ultrasonic assisted methods and were then encapsulated by freeze‐drying in soy phosphatidylcholine vesicles with the addition of different polymers, such as pectin, acacia gum, and whey protein isolate. The goal of this research was to microencapsulate anthocyanin compounds extracted from grape skins, to characterize the stability and behavior of the vesicles and then to use them to obtain a new light formulated mayonnaise. RESULTS: The particle size ranged from 900 nm in the control condition to 250 nm in vesicles loaded with whey proteins. The powders showed higher encapsulation efficiency for all variants, ranging from 81 to 96%. Vibrational spectroscopy revealed better inclusion of anthocyanins in polysaccharide‐based coacervates, whereas in protein‐based coacervates a possible interaction of anthocyanins with amine groups was observed. The vesicles were tested for in vitro release, and the results confirmed the gradual release of the anthocyanins in both stages of digestion, with a residual content of about 50% in the vesicles. The powders displayed high stability during storage in the dark at 4 °C. The panelists appreciated the new light formulated mayonnaises enriched with 10% dried vesicles compared with the control sample, in particular samples with acacia gum. CONCLUSION: The study revealed that polymer‐loaded vesicles presented stability in simulated gastrointestinal fluids and have proved successful in obtaining new light enriched mayonnaises. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Epoxy resins have been presenting a lot of scientific and technical interests and organic modified epoxy resins have recently receiving a great deal of attention. For obtaining the composite materials with good mechanical proprieties, a large variety of organic modification agents were used. For this study gluten and gelatin had been used as modifying agents thinking that their dispersion inside the polymer could increase the polymer biocompatibility. Equal amounts of the proteins were milled together and the obtained compound was used to form 1 to 5% weight ratios organic agents modified epoxy materials. To highlight the effect of these proteins in epoxy matrix mechanical tests as three-point bending and compression were performed. [ABSTRACT FROM AUTHOR]

In this investigation, the specific heat of four fabric reinforced hybrid composite materials with filled stratified epoxy matrix was analysed. All hybrid composite materials were made of 17 layers, for which were used carbon, aramid, glass and hybrid fabrics. The stratified filled epoxy matrix of fabric reinforced hybrid composites represents a matrix, in whose structure it was used three types of fillers mixtures between certain plies. The investigation of specific heat of hybrid composite materials was performed by using of Differential Scanning Calorimetry instrument. It was analysed the effects of fiber orientation at various angles on specific heat of fabric reinforced hybrid composites with filled stratified epoxy matrix and the influence of fillers mixtures on these thermal properties of epoxy matrix. Also, it was studied the specific heat of hybrid epoxy composites in dependence of carbon and aramid plies number in studied materials structure. [ABSTRACT FROM AUTHOR]

Diclofenac (DCF) is a non-steroidal anti-inflammatory drug and, as pollutant, it represents a persistent residue hazard to health and to the environment. Trametes versicolor was previously selected for its ability in diclofenac biodegradation (up to 20%) during cultivation in submerged system under aerobic conditions at an initial DCF concentration of 10 mg L-1. The influence of some factors such as nitrogen sources glucose, MnSO4•H2O, CuSO4•5H2O, inoculum level, initial DCF concentration and incubation time, upon the biodegradation potential was examined by Plackett-Burman analysis. The parameters significantly influencing the DCF biotransformation were found to be yeast extract, glucose, CuSO4•5H2O and inoculum level. In these optimum conditions, the DCF biotransformation yield was 80%. This result was 60% superior in comparison with the medium without optimization. Analysis of variance exhibited a high coefficient of determination (R²) value of 0.9987 and ensured that the polynomial model with the experimental data was a satisfactory one. Optimal conditions obtained in this work led to a solid foundation for further use of Trametes versicolor in biotreatment of high strength DCF pollutant effluents in water wastes. [ABSTRACT FROM AUTHOR]

Water quality assessment can be defined as the evaluation of the physical, chemical and biological parameters of water in relation to natural quality, human effects and intended uses. The present paper's aim was to determine the water quality collected from different areas of Lower Danube Euroregion, Romania, in Galati and Tulcea regions. The chemical and microbiological quality of the investigated groundwater and surface water indicates a low level of organic contamination. [ABSTRACT FROM AUTHOR]

Thirty wild new strains of filamentous bacteria belonging to the genus Streptomyces isolated from different Romanian soil samples and ten strains from Collection of microorganisms of Bioaliment Research Platform (acronym MIUG) were tested and screened for their ability to produce extracellular tyrosinase and laccase. Based on preliminary qualitative screening assays for the extracellular phenoloxidases production carried out by stationary cultivation on Gause agar medium (GMA) supplemented with 1% (w/w) L-tyrosine, nineteen strains were selected as active producers. Furthermore, a quantitative selection based on active strains ability to produce tyrosinase and laccase by submerged cultivation in liquid Gause salts basal medium supplemented with 1 g L-1 L-tyrosine and 0.001 g L-1 CuSO4, during 168 hours was performed. Results showed that 70% of the Streptomyces strains have a good potential for producing tyrosinase and 30% of strains were remarked for their ability to produce laccase. Moreover, it was observed that, Streptomyces strains coded MIUG 4.89 and MIUG 4.88 from MIUG Collection have the ability to simultaneously produce both enzymes. The effect of temperature and pH on enzymes activity was also investigated. The optimum temperature for both activity (tyrosinase and laccase) was found to be 30°C. Laccase was found active over a pH range of 4.0 to 6.0 with maximum activity at pH 5.0. The optimum pH for tyrosinases activity was observed to be around 7.0. The obtained results are important for future applications of Streptomyces phenoloxidases in different areas. [ABSTRACT FROM AUTHOR]