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The discharge of industrial effluents, such as phenol, into aquatic and soil environments is a global problem due to its serious negative impacts on human health and aquatic ecosystems. In this study, the ability of polyvinylpolypyrrolidone (PVPP) to remove phenol from an aqueous medium was investigated. The results showed that a significant proportion of phenol (up to 74.91%) was removed using PVPP at pH 6.5. Isotherm adsorption experiments of phenol on PVPP indicated that the best-fit adsorption was obtained using Langmuir models. The response peaks of the hydroxyl groups of phenol (OH) and the carboxyl groups (i.e., C=O) of PVPP were altered, indicating the formation of a hydrogen bond between the PVPP and phenol during phenol removal, as characterized using 1D and 2D IR spectroscopy. The resulting complexes were successfully characterized based on their thermodynamic properties, Mulliken charge, and electronic transition using the DFT approach. To clarify the types of interactions taking place in the complex systems, quantum theory of atoms in molecules (QTAIM) analysis, reduced density gradient noncovalent interaction (RDG-NCI) approach, and conductor-like screening model for real solvents (COSMO-RS) approach were also successfully calculated. The results showed that the interactions that occurred in the process of removing phenol by PVPP were through hydrogen bonding (based on RDG-NCI and COSMO-RS), which was identified as an intermediate type (∇2ρ(r) > 0 and H < 0, QTAIM). To gain a deeper understanding of how these interactions occurred, further characterization was performed based on adsorption mechanisms using molecular electrostatic potential, global reactivity, and local reactivity descriptors. The results showed that during hydrogen bond formation, PVPP acts as a nucleophile, whereas phenol acts as an electrophile and the O9 atom (i.e., donor electron) reacts with the H22 atom (i.e., acceptor electron).

Cloudiness, opalescence or a milky appearance in beverages is usually undesirable and lead the consumers to assume that the product is of lower quality. Many different types of formation and entry can lead to cloudiness and these causes can be divided into two major categories: beverage-specific, where the ingredients cause an interaction, and external influences such as process errors or particles interacting with the medium. This study considers two main sources of external influences. Raman micro-spectroscopy (RMS) was used to detect, evaluate and validate filter aids, stabilisers and various microplastic (MP) particles. A suitable sample preparation was developed, membrane filters were tested, and a filtration method for isolating the individual particles was established and implemented. To identify particles with RMS and for better representation, a few particles were selected and the results were validated using cluster analysis and the similarity matrix. The different media influences were identified by analysing the particles both dry, in water and beer. The filtration residue after membrane filtration was also analysed. A two-dimensional image scan of the particles served to determine particle homogeneity. The spectra were then recorded with single-point scans. The polyvinylpolypyrrolidone (PVPP) spectra in the different media showed similarities greater than 80%, usually greater than 95%. The cellulose spectra showed no differences between the different media, but consistently high average similarities of 94.5%. This investigation should show that foreign particles can be detected and evaluated by RMS with suitable sample preparation and recording.

Resurrection plant Ramonda serbica is a suitable model to investigate vegetative desiccation tolerance. However, the detailed study of these mechanisms at the protein level is hampered by the severe tissue water loss, high amount of phenolics and polysaccharide, and possible protein modifications and aggregations during the extraction and purification steps. When applied to R. serbica leaves, widely used protein extraction protocols containing polyvinylpolypyrrolidone and ascorbate, as well as the phenol/SDS/buffer-based protocol recommended for recalcitrant plant tissues failed to eliminate persistent contamination and ensure high protein quality. Here we compared three protein extraction approaches aiming to establish the optimal one for both hydrated and desiccated R. serbica leaves. To evaluate the efficacy of these protocols by shotgun proteomics, we also created the first R. serbica annotated transcriptome database, available at http://www.biomed.unipd.it/filearrigoni/Trinity_Sample_RT2.fasta . The detergent-free phenol-based extraction combined with dodecyl-β-D-maltoside-assisted extraction enabled high-yield and high-purity protein extracts. The phenol-based protocol improved the protein-band resolution, band number, and intensity upon electrophoresis, and increased the protein yield and the number of identified peptides and protein groups by LC-MS/MS. Additionally, dodecyl-β-D-maltoside enabled solubilisation and identification of more membrane-associated proteins. The presented study paves the way for investigating the desiccation tolerance in R. serbica, and we recommend this protocol for similar recalcitrant plant material. Supplementary material: [https://cherry.chem.bg.ac.rs/handle/123456789/4504]

A scalable, fixed-bed adsorption system for the removal and selective recovery of polyphenols (lignans and stilbenes) from medium-density fiberboard (MDF) process waters was developed. Before adsorption, fibers and non-colloidal substances were removed from process water by centrifugation, while colloidal fatty and resin acids were removed by filtration through a 30-kDa cut-off membrane. Polyphenols were then isothermally adsorbed on a medium-pressure liquid chromatography (MPLC) column packed with Divergan® RS, a regenerable macroporous, cross-linked pyrrolidone-based [polyvinylpolypyrrolidone (PVPP)] resin. Loading at acidic pH and subsequent gradient elution of polyphenols with methanol were monitored at 280 nm, and elution conditions for selective polyphenol recovery were optimized based on gas chromatography/mass spectrometry (GC/MS) analyses of the obtained fractions. Lignans were eluted in successive fractions containing the individual lignans in different proportions, followed by pinosylvin in a separate fraction. The capacity of the PVPP for hydroxymatairesinol (HMR) as a model lignan was determined to be 37.4 mg g−1 at 1% breakthrough. Highly polar substances such as sugars and sugar alcohols, however, were not retained on the column and remained in the flow-through. The results revealed the benefits of PVPP for the recovery of potentially valuable polyphenols from MDF process waters while reducing carbon load and toxicity for subsequent biological treatment.

Investigation of the appearance and elimination of “pinking” phenomenon in white wines is presented in the paper. Several factors that can cause pinking were analyzed: the degree of grapes ripeness and enzymatic treatment. The effect of fining agents based on polyvinylpolypyrrolidone (PVPP) on the elimination of “pinking” was determined. It was proved that pinking in wines decreases with an increase in the sugar content in grape. This is explained by a decrease in the content of anthocyanins at the end of technical ripeness of grape. Experimental studies confirmed that the use of pectolytic enzymes with cellulase, hemicellulase, β-glucanase activities increases the intensity of straw color and the appearance of body tones, but does not affect pinking. Such treatment contributed to a slight increase in the content of phenolic compounds in wine materials, but did not affect the content of anthocyanins and “pinking” susceptibility. Treatment of wine materials with complex PVPP-based agents including sorbents and flocculants, is an effective way to eliminate the “pinking” phenomenon. This reduces “pinking” in wine materials from 70…90 % to 1…2 %. This is due to the presence of sorbents and flocculants in the fining agents, which react with phenolic substances that cause “pinking” in white wines, and remove them from the system. So, there are reasons to argue that processing grape at the end of technical ripeness will contribute to a lower “pinking” susceptibility of wine materials; pectolytic enzymes did not affect the appearance of this phenomenon in white wines, and PVPP-based fining agents together with bentonite, activated carbon, gelatin or casein, are an effective way to reduce the “pinking” susceptibility of wine.

Investigation of the appearance and elimination of “pinking” phenomenon in white wines is presented in the paper. Several factors that can cause pinking were analyzed: the degree of grapes ripeness and enzymatic treatment. The effect of fining agents based on polyvinylpolypyrrolidone (PVPP) on the elimination of “pinking” was determined. It was proved that pinking in wines decreases with an increase in the sugar content in grape. This is explained by a decrease in the content of anthocyanins at the end of technical ripeness of grape. Experimental studies confirmed that the use of pectolytic enzymes with cellulase, hemicellulase, β-glucanase activities increases the intensity of straw color and the appearance of body tones, but does not affect pinking. Such treatment contributed to a slight increase in the content of phenolic compounds in wine materials, but did not affect the content of anthocyanins and “pinking” susceptibility. Treatment of wine materials with complex PVPP-based agents including sorbents and flocculants, is an effective way to eliminate the “pinking” phenomenon. This reduces “pinking” in wine materials from 70…90 % to 1…2 %. This is due to the presence of sorbents and flocculants in the fining agents, which react with phenolic substances that cause “pinking” in white wines, and remove them from the system. So, there are reasons to argue that processing grape at the end of technical ripeness will contribute to a lower “pinking” susceptibility of wine materials; pectolytic enzymes did not affect the appearance of this phenomenon in white wines, and PVPP-based fining agents together with bentonite, activated carbon, gelatin or casein, are an effective way to reduce the “pinking” susceptibility of wine., Статья посвящена исследованиям появления и устранения явления «pinking» в белых винах. Проанализировано несколько факторов, которые могут вызвать появление розового оттенка: степень зрелости винограда и применение ферментных препаратов. Установлено влияние препаратов на основе поливинилполипираллидона на устранение «pinking». Доказано, что с увеличением сахаристости винограда склонность к порозовению в винах снижается, что объясняется уменьшением содержания антоцианов в конце технической зрелости винограда. Установлено, что применение ферментных препаратов пектолитического действия с целлюлазными, гемицеллюлазными, β-глюканазными активностями способствует усилению интенсивности соломенного цвета и появлению телесных тонов, однако не влияет на порозовение. Такая обработка способствует незначительному увеличению фенольных соединений в виноматериалах, однако не влияет на содержание антоцианов и на склонность к «pinking». Обработка виноматериалов комплексными препаратами на основе поливиниполипирилидона, включающими сорбенты и флокулянты, является эффективным способом устранения «pinking». Склонность виноматериалов к "pinking" при этом снижается с 70...90% до 1...2%. Это объясняется наличием в препаратах сорбентов и флокулянтов, которые реагируют с фенольными веществами, ответственными за «pinking» в белых винах, выводя их из системы. Следовательно, есть основания утверждать, что переработка винограда в период окончания технической зрелости будет способствовать меньшей склонности виноматериалов к «pinking»; ферментные препараты пектолитического действия не влияют на появление этого явления в белых винах, а препараты на основе поливинилполипирралидона, являются эффективным способом снижения склонности виноматериалов к «pinking», Стаття присвячена дослідженням появи та усунення явища «pinking» в білих винах. Проаналізовано декілька факторів, які можуть спричиняти появу порожевіння: ступінь зрілості винограду та застосування ферментних препаратів. Встановлено вплив препаратів на основі полівінілполіпіралідону на усунення «pinking». Доведено, що зі збільшенням цукристості винограду схильність до порожевіння у винах знижується, що пояснюється зменшенням вмісту антоціанів наприкінці технічної зрілості винограду. Експериментальними дослідженнями підтверджено, що застосування ферментних препаратів пектолітичної дії з целюлазними, геміцелюлазними, β-глюканазними активностями сприяє посиленню інтенсивності солом’яного кольору та появі тілесних тонів, однак не впливає на порожевіння. Така обробка сприяла незначному збільшенню вмісту фенольних сполук у виноматеріалах, однак не впливала на вміст антоціанів і на схильність до «pinking». Обробка виноматеріалів комплексними препаратами на основі полівінілполіпіралідону, які включають сорбенти та флокулянти є ефективним способом усунення «pinking». Схильність виноматеріалів до «pinking» при цьому знижується 70…90% до 1…2%. Це пояснюється наявністю в препаратах сорбентів і флокулянтів, які реагують з фенольними речовинами, що спричиняють «pinking» білих вин, та виводять їх із системи. Отже, є підстави стверджувати, що переробка винограду в період закінчення технічної зрілості буде сприяти меншій схильності виноматеріалів до «pinking»; ферментні препарати пектолітичної дії не впливають на появу цього явища в білих винах, а препарати на основі полівінілполіпіралідону разом з бентонітом, активним вугіллям, желатином або казеїном, є ефективним способом зниження схильності виноматеріалів до «pinking»

Identification and quantification of different metabolites under stress, especially protein, is a vital way to understand plant adaptation mechanism. We established an efficient protein extraction method from the tiny amount (100 mg) of root tips of non-model medicinal plant Hyoscyamus albus, using bead-beating cell disruption, TRIzol extraction, and sequential chemical protein solubilization. H. albus is very well known for biosynthesized of different secondary metabolites like hyoscyamine, tropane alkaloids and scopolamine. Our method is rational for sample preparation even in small-scale proteomics of recalcitrant tissue and allows proficient, reproducible and impurity-free protein extraction. This method allows high-quality 2DE in mini-gel format (25 µg of protein/gel) for hydrophilic and hydrophobic sub-proteomes and is compatible to high-sensitive matrix-assisted laser/desorption ionization quadrupole ion trap time-of-flight (MALDI-QIT-TOF) mass spectrometry (MS). A protocol using TRIzol is more effective and reproducible to sequential chemical extraction of both hydrophilic and hydrophobic membrane proteins. We also demonstrated cell disrupted together with dithiothreitol (DTT) and polyvinylpolypyrrolidone (PVPP) is more useful to prevent polymerization of the phenolic compound than commonly used added DTT and PVPP with TRIzol reagent. Despite the unavailability of genomic sequence database, the efficacy of the protocol was also confirmed by MS/MS ion searches. J Bangladesh Agril Univ 17(4): 430–436, 2019

Factors relating to SYBR Green-based quantitative real-time PCR (qPCR) quantification of stubby root nematode Paratrichodorus allius using soil DNA were evaluated in this study. Soils used were loamy sand from potato fields in North Dakota and Idaho. Results showed that the largest nematode individuals (body length >720 µm) produced significant lower Cq values than the smallest individuals (4)(SO4)2 treatment during DNA preparation significantly reduced the inhibitors compared with post-treatment of soil DNA with polyvinylpolypyrrolidone column. The effect of PCR inhibitors on qPCR was suppressed by bovine serum albumin. Quantification results did not significantly change when increasing the number of DNA extractions from three to six per soil sample when soil grinding and grid sampling strategies were used. Two standard curves, generated from serial dilutions of plasmid DNA containing P. allius ITS1 rDNA and soil DNA containing known nematode numbers, produced similar correlations between Cq values and amount of targets. The targets in soil DNA quantified by qPCR using either standard curve correlated well with microscopic observations using both artificially and naturally infested field soils. This is the first study for assessing various factors that may affect qPCR quantification of stubby root nematodes. Results will be useful during the setup or optimization of qPCR-based quantification of plant-parasitic nematodes from soil DNA.

In the present paper, Phenolphthalein poly(ether sulfone) (PES-C) nanofibrous membranes were prepared via solution-blowing technology and polyvinylpyrrolidone (PVP) which would be converted to stable gels by reaction with potassium persulfate (K2S2O8) was immobilized on the surface of nanofibers. The influence factors such as PVP concentration and depositing time were optimized to obtain the composite nanofibrous membranes. The membranes were characterized by Scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Wide-angle X-ray diffraction (WAXD), X-ray photoelectron spectroscopy (XPS) and Water contact angles (WCA), etc. The hydrophilicity of the composite membrane was significantly enhanced by immobilizing Polyvinylpolypyrrolidone (PVPP) on the surface of nanofibers. Furthermore the filtration experiment of starch suspension and oil-water separation test were executed and the anti-fouling properties of the modified membranes were evaluated with the flux recovery ratio (FRR%). The results showed that membranes with PVPP-modified had a more excellent and stability antifouling performances compared with the original membranes. Generally, this work provides a simple and useful method to improve anti-fouling properties of PES-C nanofibrous membranes which had great potential application in microfiltration.

In this paper, we prepared a novel kind of high flux ultrafiltration (UF) membrane based on the phenolphthalein poly(ether sulfone)/polyvinylpolypyrrolidone (PVPP) composite membrane which ...

Aims This study evaluated the effects of DNA extraction method, DNA purification and pooling of PCR amplification products on the description of bacterial and archaeal diversity. Methods and results Soil DNA was extracted by the Power Soil DNA extraction kit and a customized Griffiths' protocol. Both methods are based on cell disruption by bead beating. In total, we used three soils and six independent extractions from each soil obtained by each of the two methods. Then, three of the six extracts of each treatment were further purified by spin columns filled with Sepharose 2B and polyvinylpolypyrrolidone (PVPP). The V4 hypervariable region of the 16S rRNA gene was amplified from each extract using the 515F/806R primer pair in four independent reactions. Three amplification products were combined and sequenced as a pooled sample, while the additional amplification product was sequenced individually. The resulting 72 amplification products were sequenced by Illumina MiSeq platform. DNA extraction method had a statistically significant effect on the estimation of the composition of microbial communities that might overwhelm differences in microbial communities from distinct soils. On the other hand, a further DNA purification step or pooling of PCR amplification products had a minor effect on the description of bacterial and archaeal communities. Conclusions DNA extraction had the strongest effect on the description of bacterial and archaeal communities; low concentration of impurities, which allow PCR amplification, can still generate a minor additional bias, while PCR stochastic variability had the lowest effect. Significance and impact of the study Although it is well known that methodological factors affect the description of microbial communities, the relative importance of each step is still unknown. The present study determined that of the factors tested, the DNA extraction method had the strongest effects on the description of bacterial and archaeal communities.

To absolutely and relatively quantitate the alteration of a posttranslationally modified (PTM) proteome in response to a specific internal or external signal, a 15N-stable isotope labeling in Arabidopsis (SILIA) protocol has been integrated into the 4C quantitative PTM proteomics, named as SILIA-based 4C quantitative PTM proteomics (S4Quap). The isotope metabolic labeling produces both forward (F) and reciprocal (R) mixings of either 14N/15N-coded tissues or the 14N/15N-coded total cellular proteins. Plant protein is isolated using a urea-based extraction buffer (UEB). The presence of 8 M urea, 2% polyvinylpolypyrrolidone (PVPP), and 5 mM ascorbic acid allows to instantly denature protein, remove the phenolic compounds, and curb the oxidation by free radicals once plant cells are broken. The total cellular proteins are routinely processed into peptides by trypsin. The PTM peptide yield of affinity enrichment and preparation is 0.1-0.2% in general. Ion exchange chromatographic fractionation prepares the PTM peptides for LC-MS/MS analysis. The collected mass spectrograms are subjected to a target-decoy sequence analysis using various search engines. The computational programs are subsequently applied to analyze the ratios of the extracted ion chromatogram (XIC) of the 14N/15N isotope-coded PTM peptide ions and to perform the statistical evaluation of the quantitation results. The Student t-test values of ratios of quantifiable 14N/15N-coded PTM peptides are normally corrected using a Benjamini-Hochberg (BH) multiple hypothesis test to select the significantly regulated PTM peptide groups (BH-FDR < 5%). Consequently, the highly selected prospect candidate(s) of PTM proteins are confirmed and validated using biochemical, molecular, cellular, and transgenic plant analysis.

In large-sized breweries, rough beer clarification is still carried out using Kieselguhr filters notwithstanding their environmental and safety implications. The main aim of this work was to test an innovative rough beer clarification and stabilization process involving enzymatic treating with Brewers Clarex&reg, centrifuging, rough filtering across 1.4-&mu, m ceramic hollow-fiber membrane at 30 &deg, C, and fine filtering through 0.45-&mu, m cartridge filter. When feeding an enzymatically-pretreated and centrifuged rough beer with permanent haze (HP) of 2 or 14 European Brewery Convention unit (EBC-U), its primary clarification under periodic CO2 backflushing yielded a permeate with turbidity of 1.0&ndash, 1.5 EBC-U at a high permeation flux (2.173 &plusmn, 51 or 593 &plusmn, 100 L m&minus, 2 h&minus, 1), much greater than that typical of powder filters. The final beer was brilliant (HP = 0.57 &plusmn, 0.08 EBC-U) with almost the same colloidal stability of the industrial control and an overall log reduction value (~5.0 for the selected beer spoilage bacterium or 7.6 for the brewing yeast) in line with the microbial effectiveness of current sterilizing membranes. It was perceived as significantly different in flavor and body from the industrial control at a probability level of 10% by a triangle sensory test, as more likely related to the several lab-scale beer-racking steps used than to the novel process itself.

статья посвящена изучению эффективности обработки вишневого сусла препаратами на основе поливинилполипирролидона (ПВПП) с целью предотвращения окислительного покоричневения. Приведены результаты изменения общего содержания фенольных веществ и характеристик цветности вишневых виноматериалов в результате обработки исследуемыми препаратамиthe article is devoted to the study of cherry wort processing effectiveness with preparations based on polyvinylpolypyrrolidone (PVPP) in order to prevent oxidative browning. The results of changes in total phenolic substances content and color characteristics of cherry wine materials as a result of treatment with researched preparations are presented

Histamine is a biogenic amine, produced in spoiled fish and some fermented products, which causes a foodborne disease similar to an allergic reaction. Because regulatory levels on histamine in food have been set by many countries or organizations, a quick and accurate analysis of histamine is of great interest. An enzymatic histamine determination method on the basis of a colorimetric assay has been used to detect histamine for raw and canned tuna due to its simplicity and rapidity. However, note that some compounds in fermented foods interfere with assay results. In this study, the pretreatments and conditions of the assay for fermented foods were evaluated. Lowering the reaction temperature from 37 to 23°C was considerably effective in reducing the interference. As a result, histamine in salami and sauerkraut (≥5 to 10 mg/kg) could be determined with a 25-fold dilution, as in the manufacturer's instructions. Histamine in soy sauce (≥10 to 20 mg/L) could also be determined with a 100-fold dilution. Removing fat and protein in cheese samples by using perchloric acid with a resultant 25-fold dilution and removing polyphenol with polyvinylpolypyrrolidone for red wine with a fivefold dilution were feasible; the limits of quantification were 5 mg/kg and 1 mg/L, respectively. Good recovery rates, precision repeatability, and correlations with a high-performance liquid chromatography method were confirmed. These protocols are expected to be applicable for histamine determination in various foods and useful for preventing histamine food poisoning. HIGHLIGHTS

Objective Liverworts possess historical adaptive strategies for abiotic stresses because they were the first plants that shifted from water to land. Proteomics is a state-of-the-art technique that can capture snapshots of events occurring at the protein level in many organisms. Herein, we highlight the comparison and optimization of an effective protein extraction and precipitation protocol for two-dimensional gel electrophoresis (2-DE) of liverworts. Results We compared three different protein extraction methods, i.e.,1.5 M Tris–HCl (pH 8.8), 50 mM Tris–HCl (pH 7.5), and polyvinylpolypyrrolidone (PVPP) extraction, followed by three precipitation methods, i.e., 80% ethanol, 80% acetone, and 20% tricholoroacetic acid (TCA)–acetone, in a liverwort Dumortiera hirsuta. Among these methods, 50 mM Tris–HCl (pH 7.5) extraction, followed by 20% TCA–acetone precipitation, appeared to be more suitable for 2-DE. Furthermore, we performed modifications during protein washing, re-solubilization in rehydration buffer and isoelectric focusing (IEF). The modifications provided us better results in terms of protein yield, resolution, spot numbers, and intensities for 2-DE gels of D. hirsuta and other two liverworts, i.e., Marchantia paleacea and Plagiochasma appendiculatum. Furthermore, we randomly selected spots from the 2-DE gel of D. hirsuta and identified using mass spectrometry, which confirms the applicability of this protocol for liverworts proteomics.

The present opinion deals with the re‐evaluation of polyvinylpyrrolidone (E 1201, PVP) and polyvinylpolypyrrolidone (E 1202, PVPP) when used as food additives. One request for extension of use of PVP (E 1201) in foods for special medical purposes was also considered in this assessment. The Panel followed the conceptual framework under Commission Regulation (EU) No 257/2010 and considered that: the exposure assessment was based on the reported use and use levels (one food category out of the two food categories in which PVP and PVPP are authorised); the 95th percentile of exposure to PVP and PVPP of maximally 23.7 and 25 mg/kg body weight (bw) per day in children, respectively, was overestimated, because it was assumed that 100% of the food supplements consumed contained PVP or PVPP at the maximum reported use levels; the extension of use of PVP (E 1201) to foods for special medical purposes (FC 13.2) would result in an exposure of PVP of 4.3 mg/kg bw per day for children; the absorption of PVP and PVPP is very low; sufficient toxicity data were available for PVP; there is no concern with respect to the genotoxicity of PVP and PVPP; no carcinogenic effects were reported in carcinogenicity studies in rats at a dose of 2,500 mg PVP/kg bw per day, the highest dose tested; there is no need for chronic toxicity/carcinogenicity data for PVPP for the safety assessment of PVPP given the chemical similarity between PVP and PVPP, and the lack of adverse effects in the available repeated dose toxicity studies. Therefore, the Panel concluded that there is no need for numerical acceptable daily intakes (ADIs) for PVP and PVPP, and that there is no safety concern for the reported uses and use levels of PVP and PVPP as food additives. The Panel further concluded that the proposed extension of use is not expected to be of safety concern at the proposed maximum permitted level (MPL) and recommended consumption level.

Разнообразие видов и повсеместная распространенность плодового сырья позволяет выпускать широкий ассортимент фруктовых вин. При этом одной из основных задач для производителя этой категории вин становится сохранение качественных характеристик готового продукта в течение длительного срока. В настоящей статье представлены результаты исследований эффективности препаратов на основе поливинилполипирролидона (ПВПП) с целью корректировки окраски окисленных фруктовых вин. Исследовали промышленные образцы фруктовых вин с явными признаками окисления полифенолов. Устанавливали оптимальные сроки обработки вина, а также изучали влияние температурных режимов на эффективность обработки фруктовых вин препаратами на основе ПВПП. В опытных и контрольных образцах вин определяли общее содержание фенольных веществ, показатели оптической плотности D420 и D520, а также рассчитывали показатели интенсивности окраски и оттенка. Увеличение времени контакта вина с препаратами способствовала снижению значений показателей общего содержания фенольных веществ и оптической плотности D420 и D520. Установлено, что обработка фруктовых вин при температуре 10 °С малоэффективна, в тоже время обработка препаратами при 22 °С позволила максимально снизить содержание конденсированных форм фенольных веществ. Для устранения пороков фруктовых вин, связанных с окислением и полимеризацией полифенолов оптимальное время обработки составило 3-10 сут. Показано, что обработка белых и красных фруктовых вин с признаками окисления полифенолов препаратами на основе ПВПП способствует снижению содержания коричнево окрашенных продуктов конденсации и полимеризации фенольных веществ.

Protein content and beer composition depend on the raw materials and enzymatic reactions used in brewery technology. In order to improve the colloidal stability of beer, it is necessary to remove both protein and polyphenolic complexes or prevent their formation. This study aims to determine the protein content in all production stages and to evaluate its influence on beer quality and colloidal stability. Analyzes of total protein content were performed by Kjeldahl and spectrophotometric methods. Statistically significant change was observed in the protein content of the final product, which was less than that in wort (P < 0.05). Turbididy, colour, extract, alcohol, bitterness, foam and pH were also measured. Haze forcing tests (incubation at 200C, 400C and 600 C) were conducted to evaluate the colloidal stability of the final product. Results of tests showed that the highest level of product stability was ensured after treatment of beer with both silica gel and polyvinylpolypyrrolidone (PVPP).

Polyvinylpolypyrrolidone (PVPP) is a synthetic water-insoluble polymer widely used as fining agent in the wine industry for removing low-molecular-weight phenolics. Used PVPP, estimated in 2014 of ...

A polyvinylpolypyrrolidone- (PVPP-) supported Brønsted acidic ionic liquid catalyst ([BsPVPP]HSO4) was synthesized by the reaction between SO3H-functionalized PVPP and H2SO4. The prepared catalyst was characterized by IR, XRD, FESEM, TG, and DSC. The catalytic activity of [BsPVPP]HSO4 in the preparation of tributyl citrate (TBC) by the esterification reaction between citric acid and n-butanol was investigated. Response surface methodology (RSM) was applied to optimize the process variables of the esterification reaction. The variables, including the reaction time, the n-butanol-to-citric acid mole ratio, the reaction temperature, and the catalyst amount, were optimized by a Box-Behnken design. Under optimized conditions, with a n-butanol-to-citric acid mole ratio of 5.2 : 1 and a reaction temperature of 120°C, the TBC yield reached 92.9% within 5.5 h in the presence of 6.6 wt% of catalyst; this result is in good agreement with the values predicted by the mathematical model. Moreover, the catalyst could be recycled four times with high catalytic activity.

Genetic diversity studies of plants depend upon the quality and quantity of isolated DNA sample. For many lower groups of plants, apart from usual steps involved for DNA isolation, several additional steps are invariably required specific to the particular plant group. In bryophytes, nucleic acid isolation has always been a difficult task. The Bryophytes possess a substantial quantity of polyphenols and polysaccharides that are known to interfere with DNA isolation and Polymerase chain reaction amplification. In order to overcome these problems, an improved protocol is developed for DNA isolation by optimizing important components of the cetyltrimethylammonium bromide (CTAB) extraction protocol by varying concentrations of CTAB (2–4%), polyvinylpolypyrrolidone (PVP) (0–4%) and β-mercaptoethanol (0–1.5%). It was observed that CTAB (3%), PVP (2%), and β-mercaptoethanol (1%) is optimum with a DNA yield of 900–1582 µg/0.5 gm leaf sample. DNA concentration (25 ng/µl), MgCl2 (1.5 mM), primer (1 µm), annealing temperature (48–52 °C) and a number of cycle set at 35 is optimum for the reproducible and high-intensity Simple sequence repeats amplification. The efficacy of this protocol has been validated in 6 moss taxa and 2 liverwort taxa.

The aim of this study was to determine the potential of seven clarifying agents to remove pesticides in red wine. The presence of pesticides in wine consists a great problem for winemakers and therefore, results on pesticide removal by clarification are very useful for taking a decision on the appropriate adsorbent. The selection of an efficient adsorbent can be based on data correlating pesticide removal in red wine to pesticides' properties, given the great number and variety of pesticides used. So, this experimental work is focused on the collection of results with regard to pesticide removal by clarification using a great number of pesticides and fining agents. A Greek red wine, fortified with single solutions and mixtures of 23 or 9 pesticides was studied. The seven fining agents, used at two concentrations, were activated carbon, bentonite, polyvinylpolypyrrolidone (PVPP), gelatin, egg albumin, isinglass-fish glue, and casein. Pesticides were selected with a wide range of properties (octanol-water partition coefficient (log Kow) 2.7-6.3 and water solubility 0.0002-142) and belong to 11 chemical groups. Solid phase extraction (SPE) followed by gas chromatography (GC) with electron capture detector (ECD) were performed to analyze pesticide residues of the clarified fortified wine. The correlation of the clarifying agents' effectiveness to pesticide's chemical structure and properties (log Kow, water solubility) was investigated. The antagonistic and/or synergistic effects, occurring among the pesticides in the mixtures, were calculated by indices. Pesticide removal effectiveness results of the red wine were compared to those obtained from a white wine under the same experimental conditions and discussed. The order of decreasing adsorbent effectiveness (mixture of 23 pesticides) was: activated carbon 40% > gelatin 23% > egg albumin 21% > PVPP 18% > casein 12% > bentonite 7%. Isinglass showed 12% removal at the highest permitted concentration. In the case of 9 pesticides mixture, the effectiveness was quite higher but the order remained the same compared to 23 pesticides mixture. The removal of each pesticide from its single solution was generally the highest (particularly for hydrophobic pesticides). Adsorption on fining agents is increased by increasing hydrophobicity and decreasing hydrophilicity of organic pesticide molecules.

Cimini A, Moresi M (2018) Combined enzymatic and crossflow microfiltration process to assure the colloidal stability of beer. LWT - Food Science and Technology, 90: 132-137. In this work, two beers of the industrial and craft types were stabilized and clarified by combining a commercial enzyme preparation of fungal origin (Brewers Clarex®), which is commonly used for the production of gluten-free beers, with crossflow microfiltration. By resorting to some European Brewing Convention indicative forcing tests (i.e., sensitive proteins, alcohol chill haze, and chill haze development), it was possible to confirm the efficacy of the enzyme preparation for both beers examined. By combining the enzymatic and polyvinylpolypyrrolidone (PVPP) treatments, each beer exhibited a greater colloidal stability with respect to that achievable with any single treatment. Independently of the stabilizing pretreatment used, final membrane clarification gave rise to permeated beers with almost the same chill haze development. By coupling the enzymatic treatment to crossflow microfiltration, it would be possible to replace PVPP, and avoid its expensive recovery and regeneration processes, thus leading to a simpler one-step beer conditioning process.