Interphase distribution of a number of polybasic carboxylic acids in aqueous two-phase systems based on polyethylene glycol-1500

In this work, we studied the interphase distribution of a number of polybasic carboxylic acids, in particular, malic, succinic, glutaric, citric, ascorbic and tartaric in two-phase aqueous systems polyethylene glycol-1500 (PEG-1500) - sodium sulfate - water and PEG-1500 - ammonium sulfate - water. Using the spectrophotometric method of analysis, quantitative characteristics (interfacial distribution and degree of recovery) of the extraction of carboxylic acids were determined. In conclusion, it was found that the considered two-phase aqueous systems are promising in the process of extraction of polybasic carboxylic acids. In particular, the system polyethylene glycol 1500 - sodium sulfate - water has effective extraction properties for succinic malic and ascorbic acids. On the other hand, depending on the composition of the extraction systems, the quantitative characteristics for citric, glutaric and tartaric acids practically do not differ.

COMPREHENSIVE STUDY OF THE PROFILE OF FREE ORGANIC ACIDS IN FRUITS OF SEA BUCKTHORN (HIP-POPHAE RHAMNOIDES L.) OF VARIOUS VARIETIES

An important role in the metabolism of ripening plant fruits is assigned to such a group of biologically active substances (BAS) as organic acids. This group of compounds accumulates in the fruits of plant objects in significant quantities, and the nature of the accumulation is in close relationship with metabolic processes, and is also determined by the influence of environmental factors, species and varietal characteristics of the plant. One of the promising plant sources of this group of BAS is the fruits of sea buckthorn (Hippophae rhamnoides L.). On the example of the fruits of ten different varieties of this plant, a comparative study of the profile of free organic acids was carried out using a complex of different methods of analysis (capillary electrophoresis (CE), thin layer chromatography (TLC), titrimetry). The cultivars with the maximum and minimum accumulation of BAS were identified. It was found that the composition of organic acids for the representatives of the variety samples is not the same, the maximum separation of chromatographic zones is observed in the variety «Ryabinovaya», the minimum - in the varieties «Stolichnaya», «Galerit», «Botanicheskaya», «Botanicheskaya amateur». The studied fruits were found to contain oxalic, malic, succinic and tartaric acids, identified using reliable standard samples. In the course of the research, specific marker zones were established, which can characterize the belonging of the fruits to a particular variety. The most informative is the method of СE, as it allows for one analytical procedure to carry out the qualitative and quantitative determination of free organic acids in acid and salt forms. However, complete information on the composition and quantitative content of acids can be obtained only by combining TLC and CE methods.

The comparative analysis of some Hungarian and Moldovan wines: The promise of protected geographical indication

Hungary and Moldova are excelling in unique wines and alcoholic beverages that could qualify for the protected geographical indication (PGI) by emphasizing parameters attributable to the geographical area, production or processing methods. In this study, we have assessed some parameters of wine and brandy samples looking for specificities. The studied samples were of Moldovan and Hungarian Cabernet Sauvignon red wines, Hungarian Furmint white wines, and Moldovan wine distillate/brandy called Divin. The assessed samples were evaluated for: total polyphenol and flavonoid, ethanol, malic, citric, lactic, tartaric acids, reducing sugar, glycerol, carbon dioxide, total and free SO2 content as well as for total acidity, volatile acidity, pH, and wine density. Our results indicate that despite the relatively close geographical vicinity of Hungary and Moldova, the wines produced in the two countries have specific composition, antioxidant activity, and sensorial properties. Thus, the registration of such wines as PGI is clearly justified, and such a label itself does represent a competitive advantage worth promoting.

Chemical Composition of White Wines Produced from Different Grape Varieties and Wine Regions in Slovakia

In this work, chemical parameters such as sugar (glucose and fructose) content, organic acid (total acids, malic and tartaric acids), total phenolic content and the antioxidant activity of 12 white wines (chardonnay, pinot blanc and pinot gris) from various wine regions in Slovakia were studied in order to identify differences among the varieties and wine-growing regions. The wine samples were examined by Fourier-transform infrared spectroscopy (FTIR) and UV-VIS spectrophotometry (for determination of total polyphenolic content (TPC) and total antioxidant activity (TAA)) methods. Content of alcohol ranged between 11.50% and 13.80% with the mean value 12.52%. Mean content of total acids varied between 4.63 ± 0.09 and 6.63 ± 0.05 g.L−1, tartaric acid varied between 1.62 ± 0.09 and 2.93 ± 0.03 g L−1, malic acid was found in the concentrations ranged from 0.07 ± 0.05 and 2.50 ± 0.08 g L−1 and lactic acid was present between 1.53 and 0.01 g L−1. The content of fructose was, in general, higher in the samples from the Južnoslovenská and Nitrianska wine regions and glucose was higher in the Malokarpatská wine region. Chardonnay wines showed the highest content of total polyphenols and the antioxidant activity in the samples ranged from 51.06 ± 027 to 72.53 ± 0.35% inhibition of DPPH. The PCA analysis based on chemical descriptors distinguished the Nitrianska and Stredoslovenská wine regions. According to similarities among the wine samples, four main classes were formed by cluster analysis.

Maleic and l-tartaric acids as new anti-sprouting agents for potatoes during storage in comparison to other efficient sprout suppressants

Inhibiting sprouting of potatoes is an interesting subject needed for potato storage and industry. Sprouting degrades the quality of tuber along with releasing α-solanine and α-chaconine, which are harmful for health. Sprout suppressants, available in the market, are either costly or toxic to both health and environment. So, there is a need for developing countries to explore new sprouting suppressant compound which is cheap, non-toxic and reasonably efficient in comparison to commercial ones. We have established that simple maleic acid and l-tartaric acid are effective sprout suppressing agents. Both can hinder sprouting up to 6 weeks and 4 weeks post treatment respectively at room temperature in dark. These do not affect the quality parameters, retain the moisture content and maintain the stout appearance of the tubers along the total storage period. Thus maleic acid and l-tartaric acid would qualify as alternative, cheap, efficient sprout suppressant for potato storage and processing.

Investigating the Potential Plasticizing Effect of Di-Carboxylic Acids for the Manufacturing of Solid Oral Forms with Copovidone and Ibuprofen by Selective Laser Sintering

In selective laser sintering (SLS), the heating temperature is a critical parameter for printability but can also be deleterious for the stability of active ingredients. This work aims to explore the plasticizing effect of di-carboxylic acids on reducing the optimal heating temperature (OHT) of polymer powder during SLS. First, mixtures of copovidone and di-carboxylic acids (succinic, fumaric, maleic, malic and tartaric acids) as well as formulations with two forms of ibuprofen (acid and sodium salt) were prepared to sinter solid oral forms (SOFs), and their respective OHT was determined. Plasticization was further studied by differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). Following this, the printed SOFs were characterized (solid state, weight, hardness, disintegration time, drug content and release). It was found that all acids (except tartaric acid) reduced the OHT, with succinic acid being the most efficient. In the case of ibuprofen, only the acid form demonstrated a plasticizing effect. DSC and FTIR corroborated these observations showing a decrease in the glass transition temperature and the presence of interactions, respectively. Furthermore, the properties of the sintered SOFs were not affected by plasticization and the API was not degraded in all formulations. In conclusion, this study is a proof-of-concept that processability in SLS can improve with the use of di-carboxylic acids.

Effect of Synthetic and Organic Chelators Application on Copper Phytoextraction by Calendula Officinalis L.

Background: Using ornamental plants for phytoremediation of Heavy Metals (HMs) in soil environments has been grown due to its cost-effectiveness and ease of use in urban environments. The aim of this study was to assess the potential use of Calendula officinalis for soil Copper (Cu) phytoremediation in the presence of different types of chelating agents (Ethylene Diamine Tetra-Acetic Acid (EDTA), Citric acid (CIT), and Tartaric Acids (TAR)) at different levels of Cu in a calcareous soil. Methods: To investigate the effects of stress caused by the use of chelating agents on biochemical changes of C. officinalis, the activity of some antioxidants of C. officinalis (Superoxide Dismutase (SOD), Catalase (CAT), Ascorbate Peroxidase (APX), Peroxidase (POD), and Polyphenol Oxidase (PPO)) was evaluated. Results: As results, C. officinalis showed an increase in shoot and root Cu concentration in the presence of all chelating agents compared to the control. The highest accumulation of Cu in the root/shoot was observed in EDTA-treated plants. However, an increased Cu level in plant parts (due to consuming of EDTA) was corresponded to lower dry weight in shoot and root; higher H2O2 and malondialdehyde (MDA) contents, and antioxidant activity (APX, PPO, CAT, SOD, and POD) in plants compared to the control treatment. On the contrary, the application of CIT and TAR primarily increased shoot and root dry weight and Cu concentration. Conclusion: Generally, the results of this study could be suggested that plants possess a well-organized resistance mechanism against oxidative stress caused by using of CIT and TAR.

The Effect of Chelate Compounds on the Hydration Process of MgO–Al2O3 Phase System under Hydrothermal Conditions

In refractory castables during heat treatment, there is a dynamic change from a hydraulic bond to a ceramic bond. During heating, the emission of water takes place; this changes the conditions inside the material to something similar to the hydrothermal ones. This influences the processes that occur during the heating of the castables, and in consequence, the properties of the final material. The aim of the work was to evaluate the influence of the chelate compounds like citric and tartaric acids, often used in castables as dispersing agents, on the properties of the MgO–Al2O3 phase system during hydrothermal treatment. The performed tests included an XRD analysis, a thermal analysis (TG–DSC–EGA), infrared spectroscopy (FTIR), and an SEM–EDS analysis. Based on the obtained results, it was found that even small amounts of chelate compounds have a strong impact on the processes under hydrothermal conditions which results in changes in the phase composition of the materials.

Selective separation of lactic, malic, and tartaric acids based on hydrophobic deep eutectic solvents of terpenes and amides

Inspired by traditional solvents for carboxylic acids extraction not environmentally friendly, novel hydrophobic deep eutectic solvents (DESs) based on amides as hydrogen bond acceptors (HBAs) and terpenes as hydrogen bond...