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This study aims to investigate the potential for biodiesel production from oilseed crops in Serbia, using a novel assessment method. The method involves calculating the arable land area that can be utilized for raw material production for the biodiesel industry. The available land for the production of biodiesel feedstocks is determined by subtracting the land required to meet the food needs of the domestic population and livestock from the maximum oilseed production area, which is defined as 20% of the total arable land area in Serbia. The findings reveal that approximately 353,000 hectares of land are available for producing raw materials for biodiesel production without compromising the domestic food supply. This land can provide enough raw materials to produce up to 324,000 tonnes of biodiesel annually, equivalent to 15.2% of the total domestic diesel fuel consumption for transportation in 2021.

This work examines pressurized accelerated oxidation by a RapidOxy tester as an alternative method for determination of biodiesel oxidation stability. Sunflower oil-based biodiesel was synthesized and treated with antioxidants: tert-butylhydroquinone (TBHQ) - a synthetic antioxidant known for its powerful protective effect, and a mixture of bio-based antioxidant compounds extracted from vinery waste, VWEeth. The antioxidant potency of TBHQ was evaluated at varying temperatures (110 - 140 °C) and concentrations (250 - 2,000 mg dm-3) by the RapidOxy method; assessment of selected results was performed by comparison with relevant data obtained by the standard Rancimat method. VWEeth was added in two high dosages to biodiesel (87,500 and 150,000 mg dm-3) and analyzed at 140°C by the RapidOxy method. Both antioxidants at all applied dosages showed beneficial effects on improving the oxidative stability of biodiesel, but not all of the achieved improvements reached the stability minimum identified by the EN14214 standard. The lowest addition of TBHQ seemed to have a similar effect as the tested dosages of VWEeth but these additions did not increase the induction period above the limit of 8 h; two-fold higher quantity of TBHQ was successful in this respect, increasing the initial oxidation stability by a factor of about 2, which was determined by both methods. The RapidOxy method proved to be a very fast method suitable for testing a large number of samples, which is particularly important for efficient testing of different types and doses of antioxidants.

This study evaluates six formulations in improving the oxidation stability of different fatty acid methyl esters (MEs). Two MEs differed in the unsaturation levels as they were synthesized from different feedstock: a blend of soybean and sunflower oils, and waste cooking oil; they did not fulfill the requirements of the EN 14214 standard concerning their oxidation stability (≈0.6 h) and some impurities. The third MEs (SoSuME-EN) were fully compliant with the standard. Five formulations were phenolic-based, containing single or mixed antioxidant compounds of different molecular structures; one was amine-based. Different dosages of the formulations were added to the ME samples (corresponding to the addition range 50–48300 ppm). The MEs stability expressed as induction periods, IP, determined by the Rancimat method, were used for the calculation of stabilization factors, SF, indicating the efficiency of the applied formulation. The formulation containing 2-(1,1-dimethylethyl)- 1,4-benzenediol was the most efficient concerning the lowest consumption rate and the highest SF achieved for the low quality ME. 2,2′-Methylene- -bis-(4-methyl-6-tert-butylphenol) was linked with higher antioxidant potency than the amine-based formulation and the phenolic compounds with two bulky tert-butyl groups. Among the 4 selected phenolic additives, butylated hydroxytoluene and 2,2′-methylene-bis-(4-methyl-6-tert-butylphenol) had similar efficiency in SoSuME-EN (at ≈500 ppm they produced SF ≈ 2), while it took twice of this amount for mixed butylphenols to achieve the same effect.

Paper presented is focused on the operating measurements of a tractor wet disc brake system. Operating measurements were evaluated after tractor’s operation at 500 Mth on the 3rd, 4th and 5th gear. Reference fluid and ecological fluid were tested during operation. In addition, work results include the evaluation of the fluid samples taken during the operational tests to monitor the tractor braking performance with wet disc brakes. Fluid samples were also tested in order to determine the changes in their physico-chemical properties. Chemical analysis was performed for both oil samples by means of X-ray fluorescence analysis according to the DIN 51829 and DIN 51399-2. Observed physical properties of the tested oils – density, viscosity, acid number, water content – were within the appropriate ranges after the end of test. Further analysis was focused on an amount of abrasive metals, contaminants, additives, and other important elements. On the basis of analyses conducted, it can be concluded that majority of elements preserved their original level showed at the 0 reference hour sample. In terms of the abrasion metals, an increase in their presence was not found. Furthermore, analysis of the physical properties of tested fluids did not prove their negative impact on the tractor wet disc brake system. Results of the operating measurements suggest that neither the applied conference fluid nor the ecological fluid showed negative effect on the minimum braking value. The minimum braking deceleration was implemented in accordance with the Law no. 106/2018.

Dabigatran is a novel oral anticoagulant preferred due to its ease of use, favorable pharmacokinetics, decreased potential for drug-drug interactions, and the lack of monitoring requirements. With the growing use of dabigatran, it is important to highlight that dabigatran increases the risk of hemorrhage after some procedures. Therefore, when dabigatran is used before the elective or urgent procedures, it is necessary to compare the thromboembolic event risk with the relative risk of bleeding. Before the approval of a reversal agent, the lack of specific antidotes had been the major limitation against the widespread utilization of dabigatran. In October 2015, idarucizumab, a humanized monoclonal antigen-binding antibody fragment capable of reversing the anticoagulant activity of dabigatran, has been introduced into the market to be used in lifethreatening bleeding or urgent surgery. In this manuscript, the preoperative management of dabigatran and the initial experience of using idarucizumab in a patient with nonvalvular atrial fibrillation were described. We propose that the option of dabigatran reversal needs to be considered in patients with nonvalvular atrial fibrillation. However, additional research is needed to define optimal perioperative management of dabigatran and other novel oral anticoagulants, especially in high bleeding risk patients, and to determine whether pre-procedure coagulation testing should be performed.

The critical role of energy in contemporary life and the environmental challenges associated with its production imply the need for research and exploration of its novel resources. The present review paper emphasizes the continuous exploitation of non-renewable energy sources, suggesting the transition toward renewable energy sources, termed 'green energy', as a crucial step for sustainable development. The research methodology involves a comprehensive review of articles, statistical data analysis, and examination of databases. The main focus is biomass, a valuable resource for bioenergy and biopesticide production, highlighting not only its traditional diverse sources, such as agricultural waste and industrial residues, but also non-edible invasive alien plant species. This study explores the utilization of invasive alien species in circular economy practices, considering their role in bioenergy and biopesticide production. The potential conflict between bioproduct acquisition and food sector competition is discussed, along with the need for a shift in approaching non-edible biomass sources. The paper emphasizes the untapped potential of under-explored biomass resources and the necessity for policy alignment and public awareness. Species with a significant potential for these sustainable strategies include Acer negundo L., Ailanthus altisima (Mill.) Swingle., Amorpha fruticosa L., Elaengus angustifolia L., Falopia japonica (Houtt.) Ronse Decr., Hibiscus syriacus L., Koelreuteria paniculata Laxm., Paulownia tomentosa Siebold and Zucc., Partenocissus quenquefolia (L.) Planch., Rhus typhina L., Robinia pseudoacacia L. and Thuja orientalis L. In conclusion, the paper highlights the intertwined relationship between energy, environmental sustainability, and circular economy principles, providing insights into Serbia's efforts and potential in adopting nature-based solutions for bioenergy and biopesticides acquisition. [ABSTRACT FROM AUTHOR]

Influence of the process parameters for the industrially relevant reaction of free fatty acid (FFA) with glycerol is investigated. Furthermore, several drying techniques are investigated and a novel method is suggested that can provide more realistic experimental conditions. Silica as an absorbent is found to be a more suitable method for water removal than distillation or carrier gas. Using response surface methodology, important parameters are identified and optimal conditions found. Empirical correlation is developed to account for the most important parameters. Both oil:glycerol ratio and temperature have optimal values for which the highest conversion can be achieved. Interestingly, the highest conversion can be obtained at 220°C; above this temperature the conversion decreases. It is found that the influence of oil:glycerol ratio also exhibits anomalous behavior, where conversion is constant and decreases above a certain value. At optimal conditions, the FFA is reduced to 1.6% from the initial 8.6%.

The paper focuses on the area of experimental measurements for monitoring the impact of decarbonization on the technical and environmental parameters of the ICE. The condition for the implementation of the measurements was the selection of an ICE that had driven more than 300,790 km. During the laboratory tests, several test methods were used to assess the technical and emission conditions of the tested ICE with the code designation ALH, which is used in VOLKSWAGEN BORA vehicles. The technical parameters of the tested ICE (corrected power PNorm and torque MMom), emission parameters (absorption coefficient k and NOx emission) and fuel consumption parameters (specific fuel consumption bsfc) were compared and evaluated in the results. The results show that the decarbonization process on the tested vehicle VOLKSVWAGEN BORA 1.9 TDi affected the emission parameters but did not affect the technical parameters and specific fuel consumption. [ABSTRACT FROM AUTHOR]

The influence of the physicochemical properties of a series of CaO catalysts activated at different temperatures on the biodiesel production was investigated. These catalysts show dissimilar yields in the transesterification of triglycerides with methanol. We have found significant relationships between structural properties (the type of the pore system, the typical CaO crystal phase and the sizes of crystallites (up to 25 nm), the minimal weight percentage of CaO phase, the total surface basicity and potential existence of two types of basic active sites) of CaO prepared and activated by means of thermal treatment at highest temperature and catalytic efficiency. Benefits of this catalyst are short contact time, standard operating temperature and atmospheric conditions, relatively low molar ratios and small catalyst loading. These all together resulted in a very high biodiesel yield of high purity. The properties of different biodiesel (obtained with the use of the prepared CaO catalyst) blends with different diesel and biodiesel ratios indicate that the higher the fraction of biodiesel fuel the better the achieved fuel properties according to the EU standards. A significant reduction of CO2 and CO emissions and only a negligible NOx increase occurred when blends with an increased biodiesel portion was used. The use of biodiesel derived blends, and the eventual complete replacement of fossil fuels with biodiesel as a renewable, alternative fuel for diesel engines, would greatly contribute to the reduction of greenhouse gases emissions. [Projekat Ministarstva nauke Republike Srbije, br. ON 172061 i TR 34008]

This paper presents a complete characterization of rapeseed oil, of Banaćanka variety, as well as the potential use of oil generated after filtering, in order to obtain biodiesel. Researches are based on the fact that Banaćanka is the oldest domestic rapeseed variety, the so-called double zero "00" (low in erucic acid, below 5%, and glucosinolates below than 30 mmol g-1), suitable for use in the region, since it is low temperatures tolerant, posseses high genetic potential for seed yield of about 5.2 t/ha, and high oil content of around 45%. Transesterification was carried out in batch reactor Parr 4520, with KOH as a catalyst. Cold pressed oil without prior treatment was used as feedstock for transesterificataion. The paper analyses the effects of temperature, reaction duration, catalyst amount and rate of agitation on the synthesis of biodiesel at constant pressure and molar methanol/oil ratio.[Projekat Ministarstva nauke Republike Srbije, br. TR-31046: Improvement of the quality of tractors and mobile systems with the aim of increasing competitiveness and preserving soil and environment]

The presented article deals with the design of equipment for measuring and testing hydrostatic transducers. The presented design of the device is used for measuring and testing hydrostatic transducers in laboratory conditions, especially hydraulic pumps. This shortens the testing time, with a reduction in economic costs for testing the elements of the hydraulic circuit or testing the properties of pumps and hydraulic fluids. By simulating the operating conditions occurring in practice, it is possible to verify and evaluate the parameters of mobile energy means used in hydraulic mechanisms. The designed laboratory equipment is used for measuring and testing hydrostatic transducers and properties of hydraulic fluids. A verification measurement of the flow of the hydrostatic transducer was performed on the proposed laboratory equipment. The output of the measurements is a confirmation of the functionality of the designed equipment. The results of the verification measurement were compared with the data obtained during the simulations in the computer program FluidSIM 5. The output of the measurements is a confirmation of the functionality of the designed equipment. When comparing the results of the verification measurement of the flow on the laboratory equipment with the data given by the manufacturer of the transducer, we recorded a decrease in flow of 5.1% at a speed of 250 rpm in comparison. At 500 rpm we recorded an increase in flow of 2.38% and at 750 rpm there was an increase of 4.15% compared to the data from the manufacturer. The results of the verification measurements were also compared with the simulation in the computer program FluidSIM 5. The flow data obtained by the simulation showed higher values than in the verification measurement. Specifically, at 250 rpm it was an increase of 3.21%, at 500 rpm by 0.39%, and at 750 rpm by 3.14%. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to evaluate patterns among export diversification along with the economic development in the CEFTA 2006 region. The pattern, which is evaluated here, is a hump-shaped pattern, which states that diversification and re-concentration of export and has a „U“shape relationship with GDP per capita. Hump-shaped pattern suggests that countries add products to their export basket during the early stages of economic development, while high-income countries remove goods for which they have lost a comparative advantage. Consequently, countries are slower to specialize in exporting products in which they have a comparative advantage, which leads to a humpbacked appearance. It may be concluded that one of the driving forces for export diversification is certainly GDP per capita, where diversification and later re-concentration take place mainly through extensive margins. On the other hand, intensive margins do follow the same pattern as extensive margins. Furthermore, extensive margins represent export diversification to new markets, where intensive margins present export diversification of new products. Export diversification is closely related to commodity export dependence. The country is considered to be commodity export-dependent when more than 60 percent of its total merchandise exports are composed of commodities. In these terms, countries with lower export diversification usually suffer from slow development, non-diversified economic structures, macroeconomic instability, economic volatility, "Dutch disease", political instability, poor political and economic governance, etc. Empirical studies reveal that export diversification can promote economic growth and reduce economic volatility. Greater diversification of exports contributes to greater resilience to exogenous shocks as well as stronger long-term growth and development of the country. With greater export diversification of products and greater geographical diversification (extensive and intensive margins), the risk of exogenous negative impacts is reduced. To test the U-shaped hypothesis, we used Herfindahl–Hirschman index as a measurement for export diversification. In this paper, we used secondary data from the UNCTADstat database for export. Data for GDP per capita were gathered from the World Bank database. After calculating the mentioned index for export diversification/specialization for CEFTA 2006 region, we presented a link between mentioned indexes with GDP per capita. Our results reject the null hypothesis, which states that there is a U-shaped relationship between export diversification and GDP per capita in the CEFTA 2006 region. In the CEFTA 2006 region, countries do not follow the path of higher diversified export at lower GDP per capita, and later specialization in exporting products with an increase of GDP per capita, in a product that which they have comparative advantages. The examined period in this paper was from 2007 to 2020 (13 years). Future studies could examine what the main drivers for export diversification are in CEFTA 2006 region. Also, it would be interesting to examine which margins, extensive or intensive, are the main drivers for diversification and later re-concertation at an individual level of each country. [ABSTRACT FROM AUTHOR]

Copyright of Ekonomske Ideje i Praksa is the property of Centar za Izdavacku Delatnost Ekonomskog Fakulteta u Beogradu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Isotopes of hydrogen (3H, 2H) and oxygen (18O) are perfect candidates for groundwater tracers. A survey of isotopic composition of 34 groundwater samples and one Lake from Vojvodina region (Serbia) is presented here. Tritium activity concentration and stable isotope composition (δ2H, δ18O), as well as deuterium excess, were determined. The groundwater samples lie on the groundwater regression line. Minor deviations and a few lower deuterium excess values indicate waters recharged in a different climate regime and subjected to evaporation, respectively. According to the obtained results, most of the analyzed groundwater can be characterized as modern waters, recharged mostly from precipitation. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Medical Journal / Medicinski Časopis is the property of Serbian Medical Society, Section Kragujevac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The 5 K superconductor La [ABSTRACT FROM AUTHOR]

The discovery of iron pnictides and iron chalcogenides as a new class of unconventional superconductors in 2008 has generated an enormous amount of experimental and theoretical work that identifies these materials as correlated metals with multi-orbital physics, where magnetism, nematicity, and superconductivity are competing phases that appear as a function of pressure and doping. A microscopic understanding of the appearance of these phases is crucial in order to determine the nature of superconductivity in these systems. Here, we review our recent theoretical efforts to describe and understand from first principles the properties of iron pnictides and chalcogenides with special focus on (i) pressure dependence, (ii) effects of electronic correlation, and (iii) origin of magnetism and superconductivity. [ABSTRACT FROM AUTHOR]

We revisit the problem that relevant parts of band structures for a given cell choice can reflect exact or approximate higher symmetries of subsystems in the cell and can therefore be significantly simplified by an unfolding procedure that recovers the higher symmetry. We show that band-structure unfolding can be understood as projection onto induced irreducible representations of a group obtained by extending the original group of translations with a number of additional symmetry operations. The resulting framework allows us to define a generalized unfolding procedure that includes the point group operations and can be applied to any quantity in the reciprocal space. The unfolding of the Brillouin zone follows naturally from the properties of the induced irreducible representations. In this context, we also introduce a procedure to derive tight-binding models of reduced dimensionality by making use of point group symmetries. Further, we show that careful consideration of unfolding has important consequences on the interpretation of angle-resolved photoemission experiments. Finally, we apply the unfolding procedure to various representative examples of Fe-based superconductor compounds and show that the one-iron picture arises as an irreducible representation of the glide-reflection group, and we comment on the consequences for the interpretation of one-iron versus two-iron Brillouin zone representations. [ABSTRACT FROM AUTHOR]

Dramatic volume collapses under pressure are fundamental to geochemistry and of increasing importance to fields as diverse as hydrogen storage and high-temperature superconductivity. In transition metal materials, collapses are usually driven by so-called spin-state transitions, the interplay between the single-ion crystal field and the size of the magnetic moment. Here we show that the classical S = 5/2 mineral hauerite (MnS2) undergoes an unprecedented (ΔV ∼22 %) collapse driven by a conceptually different magnetic mechanism. Using synchrotron X-ray diffraction we show that cold compression induces the formation of a disordered intermediate. However, using an evolutionary algorithm we predict a new structure with edge-sharing chains. This is confirmed as the thermodynamic ground state using in situ laser heating. We show that magnetism is globally absent in the new phase, as low-spin quantum S = 1/2 moments are quenched by dimerization. Our results show how the emergence of metal-metal bonding can stabilize giant spin-lattice coupling in Earth's minerals. [ABSTRACT FROM AUTHOR]

The technical and environmental parameters of the diesel internal combustion engine using two new samples of biofuels SAMPLE 1 and SAMPLE 2 were evaluated in this paper. SAMPLE 1 and SAMPLE 2 biofuels were tested on a LOMBARDINI LDW 502 internal combustion engine, which was loaded on a dynamometer according to the applicable national and international standards. This method can also be applied to marine engines and contribute to a higher level of marine ecology. The result of the testing was to determine the impact of tested biofuels on the technical parameters engine power and torque and the environmental parameters emissions of smoke, nitrogen oxides, and economy of the internal combustion engine-specific fuel consumption. From the measured data, another parameter was calculated, such as the injected fuel dose and the overall efficiency of the internal combustion engine. The results show that the new samples of SAMPLE 1 and SAMPLE 2 biofuels tested could be a suitable alternative to standard diesel. [ABSTRACT FROM AUTHOR]

Starting from the orthorhombic magnetically ordered phase, we investigate the effects of uniaxial tensile and compressive stresses along a, b, and the diagonal a + b directions in BaFe2As2 and CaFe2As2 in the framework of ab initio density functional theory (DFT) and a phenomonological Ginzburg-Landau model. While-contrary to the application of hydrostatic or c-axis uniaxial pressure-both systems remain in the orthorhombic phase with a pressure-dependent nonzero magnetic moment, we observe a sign-changing jump in the orthorhombicity at a critical uniaxial pressure, accompanied by a reversal of the orbital occupancy and a switch between the ferromagnetic and antiferromagnetic directions. Our Ginzburg-Landau analysis reveals that this behavior is a direct consequence of the competition between the intrinsic magneto-elastic coupling of the system and the applied compressive stress, which helps the system to overcome the energy barrier between the two possible magneto-elastic ground states. Our results shed light on the mechanisms involved in the detwinning process of an orthorhombic iron-pnictide crystal and on the changes in the magnetic properties of a system under uniaxial stress. [ABSTRACT FROM AUTHOR]

Rapid growth in the energy consumption has conditioned the need for discovering the alternative energy resources which would be adapted to the existing engine constructions and which would satisfy the additional criteria related to the renewability, ecology, and reliability of use. Introduction of biodiesel has been the focus of attention over the last ten years. The aim of this research is to investigate the influence of biodiesel on the performances and exhaust gas emissions of medium power agricultural tractor engines (37-66 kW). The reason for the selection of this category is that those types of tractors are most frequently used in agriculture. In this research biodiesel produced from sunflower oil was blended with fossil diesel. Biodiesel, fossil diesel, and fossil diesel blends with 15, 25, 50, and 75%v/v biodiesel were tested for their influence on the engine performances and emissions. The testing was performed on a four-cylinder diesel engine with 48 kW rated power. The experimental research on the engine performances was conducted in compliance with OECD test CODE 2, and the exhaust gas emissions were tested according to the ISO 8178-4, C1. The use of biodiesel and fossil diesel blends reduced the engine power with the increase of biodiesel share in the blend. However, the exception was the blend with 15%v/v biodiesel which induced a slight increase in the engine power. Depending on the share of biodiesel in the blend all blends fuels showed increased specific fuel consumption compared to the fossil diesel. Thermal efficiency increased as a result of more complete combustion of biodiesel and fossil diesel blends. The exhaust gas emissions implied that the addition of biodiesel reduced the content of CO2 and CO, as well as the temperature of exhaust gases, but it increased the emission of NOx. [ABSTRACT FROM AUTHOR]

Power delivery efficiency shows how much engine power is used for a tractor drawbar. Eccentric traction is a factor influencing the power delivery efficiency of a wheeled tractor. It occurs as a consequence of the of set position of a tractor implement, that is, when the traction line of the tractor and resistance line of the implement are parallel and do not coincide. h is paper presents research on the power delivery efficiency of wheeled tractors and its dependence on wheel slippage of central and eccentric drawbar forces on unplowed and plowed stubble. For this purpose, mathematical models and one algorithm were developed. The best power delivery efficiency of the tractor on both unplowed and plowed stubble surfaces was obtained with central drawbar force. Power delivery efficiency of the tractor on unplowed stubble decreased by 5.72% if eccentricity increased up to 0.16 m and by 12.33% if eccentricity increased up to 0.32 m. Power delivery efficiency of the tractor on plowed stubble decreased by 8.88% if eccentricity increased up to 0.16 m and decreased by 19.05% if eccentricity increased up to 0.32 m. [ABSTRACT FROM AUTHOR]

We present uniaxial pressure structural relaxations for CaFe2As2 and BaFe2As2 within density functional theory and compare them with calculations under hydrostatic pressure as well as available experimental results. We find that CaFe2As2 shows a unique phase transition from a magnetic orthorhombic phase to a nonmagnetic collapsed tetragonal phase for both pressure conditions and no indication of a tetragonal phase is observed at intermediate uniaxial pressures. In contrast, BaFe2As2 shows for both pressure conditions two phase transitions from a magnetic orthorhombic to a collapsed tetragonal phase through an intermediate nonmagnetic tetragonal phase. We find that the critical transition pressures under uniaxial conditions are much lower than those under hydrostatic conditions manifesting the high sensitivity of the systems to uniaxial stress. We discuss the origin of this sensitivity and its relation to experimental observations. [ABSTRACT FROM AUTHOR]

In the present study, valorization of yarrow (Achillea millefolium) by-product from the filter tea industry was investigated through the application of subcritical water for the extraction of bioactive compounds. The influence of different process parameters (temperature 120–200 °C, extraction time 10–30 min, and HCl concentration in extraction solvent 0–1.5%) on extract quality in terms of content of bioactive compounds and antioxidant activity was investigated. Optimal conditions of the extraction process (temperature 198 °C, extraction time 16.5 min, and without acidifer) were determined and, when applied, the most efficient exploitation of by-products is achieved, that is, attainment of extracts rich in total phenols and flavonoids and high antioxidant activity. In addition, by applying the high performance liquid chromatographic analysis, the content of chlorogenic acid was determined as well as the hydroxymethylfurfural content in obtained extracts. The results demonstrated that subcritical water can be successfully used for utilization of yarrow by-products for obtaining extracts rich in antioxidants. [ABSTRACT FROM AUTHOR]

White horehound (Marrubium vulgare L.), is a grey-leaved perennial herb, belonging to Lamiaceae family, distributed in Eurasia and northern Africa. Despite the fact that M. vulgare has been used since ancient times in treating diverse diseases, it is only in the last decade or so that scientists have been able to lay the foundation for its potential pharmacological actions from the results observed through the prism of ethnopharmacological use of this species. The novelty of this study was that subcritical water extraction, acknowledged as a powerful extraction technology to recover phenolic compounds, was coupled with spray drying. The subcritical horehound extract, obtained using optimal process parameters, was used as a liquid feed in spray drying. Maltodextrin was used as a carrier in a concentration of 10%. Thus, two M. vulgare powders, carrier-free and 10% MD, were produced. Comprehensive powders characterization was conducted in order to evaluate their quality. Results confirmed that spray drying can be used as a method of choice for obtaining high quality horehound powders which kept the amorphous structure constant after 6 months. [ABSTRACT FROM AUTHOR]

This study evaluates six formulations in improving the oxidation stability of different fatty acid methyl esters (MEs). Two MEs differed in the unsaturation levels as they were synthesized from different feedstock: a blend of soybean and sunflower oils, and waste cooking oil; they did not fulfill the requirements of the EN 14214 standard concerning their oxidation stability (≈0.6 h) and some impurities. The third MEs (SoSuME-EN) were fully compliant with the standard. Five formulations were phenolic-based, containing single or mixed antioxidant compounds of different molecular structures; one was amine-based. Different dosages of the formulations were added to the ME samples (corresponding to the addition range 50-48300 ppm). The MEs stability expressed as induction periods, IP, determined by the Rancimat method, were used for the calculation of stabilization factors, SF, indicating the efficiency of the applied formulation. The formulation containing 2-(1,1-dimethylethyl)-1,4-benzenediol was the most efficient concerning the lowest consumption rate and the highest SF achieved for the low quality ME. 2,2′-Methylene--bis-(4-methyl-6-tert-butylphenol) was linked with higher antioxidant potency than the amine-based formulation and the phenolic compounds with two bulky tert-butyl groups. Among the 4 selected phenolic additives, butylated hydroxytoluene and 2,2′-methylene-bis-(4-methyl-6-tert-butylphenol) had similar efficiency in SoSuME-EN (at ≈500 ppm they produced SF ≈ 2), while it took twice of this amount for mixed butylphenols to achieve the same effect. [ABSTRACT FROM AUTHOR]