Evaluation of Solutions Containing Fluoride, Sodium Trimetaphosphate, Xylitol, and Erythritol, Alone or in Different Associations, on Dual-Species Biofilms.

Although the association of polyols/polyphosphates/fluoride has been demonstrated to promote remarkable effects on dental enamel, little is known on their combined effects on biofilms. This study assessed the effects of solutions containing fluoride/sodium trimetaphosphate (TMP)/xylitol/erythritol on dual-species biofilms of Streptococcus mutans and Candida albicans. Biofilms were grown in the continuous presence of these actives alone or in different associations. Quantification of viable plate counts, metabolic activity, biofilm biomass, and extracellular matrix components were evaluated. Overall, fluoride and TMP were the main actives that significantly influenced most of the variables analyzed, with a synergistic effect between them for S. mutans CFUs, biofilm biomass, and protein content of the extracellular matrix (p < 0.05). A similar trend was observed for biofilm metabolic activity and carbohydrate concentrations of the extracellular matrix, although without statistical significance. Regarding the polyols, despite their modest effects on most of the parameters analyzed when administered alone, their co-administration with fluoride and TMP led to a greater reduction in S. mutans CFUs and biofilm biomass compared with fluoride alone at the same concentration. It can be concluded that fluoride and TMP act synergistically on important biofilm parameters, and their co-administration with xylitol/erythritol significantly impacts S. mutans CFUs and biomass reduction.

Structural Determinants of Sugar Alcohol Biosynthesis in Plants: The Crystal Structures of Mannose-6-Phosphate and Aldose-6-Phosphate Reductases.

Sugar alcohols are major photosynthetic products in plant species from the Apiaceae and Plantaginaceae families. Mannose-6-phosphate reductase (Man6PRase) and aldose-6-phosphate reductase (Ald6PRase) are key enzymes for synthesizing mannitol and glucitol in celery (Apium graveolens) and peach (Prunus persica), respectively. In this work, we report the first crystal structures of dimeric plant aldo/keto reductases (AKRs), celery Man6PRase (solved in the presence of mannonic acid and NADP+) and peach Ald6PRase (obtained in the apo form). Both structures displayed the typical TIM barrel folding commonly observed in proteins from the AKR superfamily. Analysis of the Man6PRase holo form showed that residues putatively involved in the catalytic mechanism are located close to the nicotinamide ring of NADP+, where the hydride transfer to the sugar phosphate should take place. Additionally, we found that Lys48 is important for the binding of the sugar phosphate. Interestingly, the Man6PRase K48A mutant had a lower catalytic efficiency with mannose-6-phosphate but a higher catalytic efficiency with mannose than the wild type. Overall, our work sheds light on the structure-function relationships of important enzymes to synthesize sugar alcohols in plants.

Versatile roles of sorbitol in higher plants: luxury resource, effective defender or something else?

MAIN CONCLUSION: Sorbitol metabolism plays multiple roles in many plants, including energy and carbon enrichment, effective defence against various stresses and other emerging specific roles. The underlying mechanisms are, however, incompletely understood. This review provides the current state-of-the-art, highlights missing knowledge and poses several remaining questions. The basic properties of sugar alcohols are summarised and pathways of sorbitol metabolism, including biosynthesis, degradation and key enzymes are described. Sorbitol transport within the plant body is discussed and individual roles of sorbitol in different organs, specific cells or even cellular compartments, are elaborated, clarifying the critical importance of sorbitol allocation and distribution. In addition to plants that accumulate and transport significant quantities of sorbitol (usual producers), there are some that synthesize small amounts of sorbitol or only possess sorbitol metabolising enzymes (non-usual producers). Modern analytical methods have recently enabled large amounts of data to be acquired on this topic, although numerous uncertainties and questions remain. For a long time, it has been clear that enriching carbohydrate metabolism with a sorbitol branch improves plant fitness under stress. Nevertheless, this is probably valid only when appropriate growth and defence trade-offs are ensured. Information on the ectopic expression of sorbitol metabolism genes has contributed substantially to our understanding of the sorbitol roles and raises new questions regarding sorbitol signalling potential. We finally examine strategies in plants producing sorbitol compared with those producing mannitol. Providing an in-depth understanding of sugar alcohol metabolism is essential for the progress in plant physiology as well as in targeted, knowledge-based crop breeding.

Metabolomics of oxidative stress: Nrf2 independent depletion of NAD or increases of sugar alcohols.

Nrf2 encodes a transcription factor best known for regulating the expression of antioxidant and detoxification genes. Recent evidence suggested that Nrf2 mediates metabolic reprogramming in cancer cells. However, the role of Nrf2 in the biochemical metabolism of cardiac cells has not been studied. Using LC-MS/MS-based metabolomics, we addressed whether knocking out the Nrf2 gene in AC16 human cardiomyocytes affects metabolic reprogramming by oxidative stress. Profiling the basal level metabolites showed an elevated pentose phosphate pathway and increased levels of sugar alcohols, sorbitol, L-arabitol, xylitol and xylonic acid, in Nrf2 KO cells. With sublethal levels of oxidative stress, depletion of NAD, an increase of GDP and elevation of sugar alcohols, sorbitol and dulcitol, were detected in parent wild type (WT) cells. Knocking out Nrf2 did not affect these changes. Biochemical assays confirmed depletion of NAD in WT and Nrf2 KO cells due to H2O2 treatment. These data support that although Nrf2 deficiency caused baseline activation of the pentose phosphate pathway and sugar alcohol synthesis, a brief exposure to none-lethal doses of H2O2 caused NAD depletion in an Nrf2 independent manner. Loss of NAD may contribute to oxidative stress associated cell degeneration as observed with aging, diabetes and heart failure.

[Methodological aspects of determining (estimating) the content of carbohydrates in juice products when placing information for consumers on packaging].

Information about the nutritional value included by the manufacturer in the labeling of consumer packaging of foodstuffs contributes to an informed choice in the formation of the diet and is extremely important for the consumer. This information is the subject of special attention both on the part of nutrition specialists and on the part of state control (supervision) bodies. At the same time, methodological approaches to determining (evaluating) the content of carbohydrates in juice products as an important component of its nutritional value require additional elaboration. The aim of the work was to consider methods for determining (estimating) the content of carbohydrates in juice products and developing recommendations for their use. Material and methods. Methodical approaches to determining (estimating) the content of carbohydrates in juice products for the purpose of labeling consumer packaging have been considered. Determination (assessment) of the content of carbohydrates in 85 samples of juice products was carried out using calculation and analytical methods and the analysis of the data obtained has been done. Results. It has been established that the difference between the values of the carbohydrate content in juice products obtained by different methods can reach up to 20 percent. This is caused both by natural fluctuations in carbohydrate content in fruits and vegetables and, accordingly, in juices from them, and by the measurement uncertainty of the analytical methods used. The most accurate way to determine carbohydrates in juice products for consumer packaging labeling purposes is to measure and sum the content of individual sugars and sugar alcohols in the product. Next comes the calculation method based on data on the average content of sugars and sugar alcohols in industrial juices. Estimating the content of carbohydrates in a product by the determination of the content of soluble solids is the least accurate, while this method can be used with a sufficient degree of accuracy for juice products with a low juice content (10-20%). Conclusion. Methodological approaches have been developed to the choice of method for determining (estimating) the content of carbohydrates in order to label consumer packaging depending on the type of juice products. An analysis of the results obtained shows the need to specify the manufacturer's procedure for determining (evaluating) carbohydrates in products for the purpose of labeling them in the technical regulation of the Customs Union TR CU 023/2011 «Technical regulation for juice products from fruits and vegetables¼, as well as establishing possible deviations from those indicated in the labeling values.

Complex Analysis of Antioxidant Activity, Abscisic Acid Level, and Accumulation of Osmotica in Apple and Cherry In Vitro Cultures under Osmotic Stress.

Plant response to osmotic stress is a complex issue and includes a wide range of physiological and biochemical processes. Extensive studies of known cultivars and their reaction to drought or salinity stress are very important for future breeding of new and tolerant cultivars. Our study focused on the antioxidant activity, accumulations of osmotica, and the content of abscisic acid in apple (cv. "Malinové holovouské", "Fragrance", "Rubinstep", "Idared", "Car Alexander") and cherry (cv. "Regina", "Napoleonova", "Kastánka", "Sunburst", "P-HL-C") cultivated in vitro on media containing different levels of polyethylene glycol PEG-6000. Our results indicated that the studied genotypes responded differently to osmotic stress manifested as reduction in the leaf relative water content (RWC) and increment in the activities of antioxidant enzymes, proline, sugars, and abscisic acid content. Overall, cherry cultivars showed a smaller decrease in percentage RWC and enzymatic activities, but enhanced proline content compared to the apple plants cultivars. Cultivars "Rubinstep", "Napoleonova", and "Kastánka" exhibited higher antioxidant capacity and accumulation of osmoprotectants like proline and sorbitol that can be associated with the drought-tolerance system.

Optimization of prebiotic sucrose-free milk chocolate formulation by mixture design.

The purpose of the current research was to determine optimal situation by applying Simplex lattice mixture design for the formulation of prebiotic sucrose-free milk chocolate. Chocolate samples were prepared using two different sugar alcohols containing xylitol and maltitol along with galactooligosaccharide as prebiotic substance. The effects of sugar alcohols and prebiotic blends on rheological attributes and some physical characteristics were assessed. The outcomes represented the high coefficient of determination (≥ 90%) of fitted models. The optimization of the variables indicated that using 20.857 g maltitol, 7.131 g xylitol and 5.012 g galactooligosaccharide generated the optimized chocolate with the highest desirability (1.00) without undesirable changes in the rheological and physical properties. Furthermore, the optimum formulation was prepared to validate the optimum model. The sensory evaluation of the optimized formulation of chocolate pleased the consumer needs.

Sugar alcohols derived from lactose: lactitol, galactitol, and sorbitol.

Lactose is a common natural disaccharide composed of galactose and glucose molecules. It is mainly found in the whey, the by-product of cheese and casein industries. As the supply of lactose far exceeds demand, a lot of lactose was discarded as the waste every year, which not only leads to resource waste, but also causes environmental pollution. Therefore, the deep processing of lactose as the feedstock has become a hot research topic. The lactose-derived sugar alcohols, including lactitol, sorbitol, and galactitol, have shown great potential applications not only in food manufacture, but also in pharmaceutical, cosmetic, and material fields. In this paper, we focus on the property, physiological effect, production, and application of the lactose-derived sugar alcohols. KEY POINTS: • The deep processing of lactose as the feedstock has become a hot research topic. • The lactose-derived sugar alcohols show great application values. • Recent advances in the lactose-derived sugar alcohols are reviewed.

Structure and Properties of Biodegradable Poly (Xylitol Sebacate-Co-Butylene Sebacate) Copolyester.

In this work, a bio-based copolyester with good mechanical properties was synthesized and characterized in terms of structure, main properties and biodegradability Determining the chemical structure of such materials is important to understand their behavior and properties. Performing an extraction of insoluble cross-linked polymer using different solvents allowed us to analyze how the polymer behaves when subjected to different chemical environments, and to obtain soluble samples suitable for more in-depth analysis. Chemical structure of poly (xylitol sebacate-co-butylene sebacate) was determined by a 1H NMR and FTIR analysis of both prepolymer gel sample and samples obtained by extraction of cross-linked polymer using different solvents. Block structure of the copolymer was confirmed by both NMR and DSC. Gel fraction, swelling value, water contact angle, and mechanical properties were also analyzed. Biodegradability of this material was confirmed by performing enzymatic and hydrolytic degradation. Synthesizing sugar-alcohol based copolyester using three monomers leads to obtaining a material with interesting chemical structure and desirable mechanical properties comparable to conventional elastomers.

In vitro fermentation of Pennisetum clandestinum Hochst. Ex Chiov increased methane production with ruminal fluid adapted to crude glycerol.

The aim of this trial was to determine the effect of ruminal fluid adapted to crude glycerol supplementation on in vitro methane and fermentation parameters of the forage Pennisetum clandestinum Hochst. Ex Chiov (Kikuyu forage) of 35 (D35) and 45 days (D45) of regrowth. Four non-lactating cannulated Holstein cows with 600 ± 33 kg LW, under a randomized Latin square design (4 animals × 4 periods), were used to obtain ruminal fluid after adaptation for 13 days within each period to supplementation in the rumen with crude glycerol (GL): 0 (GL0), 500 (GL1), 1000 (GL2), and 1500 g/cow/day (GL3). All the variables were analyzed under a 4 × 2 split-plot arrangement, where the ruminal fluid adaptation to supplementation with GL and its interaction with the incubated diets (GL× D) were analyzed. Ruminal pH values and in vitro apparent degradability of the dry matter (DMd) and organic matter (OMd) were not affected, with a decrease in the concentrations of NH3-N and acetate by the ruminal fluid adapted to crude glycerol. The concentrations of propionate and butyrate increased, without affecting the total concentration of VFA in the ruminal fluid. The in vitro methane production increased with forage D35 and GL1, GL2, GL3. The in vitro methane production with the D45 forage increased with the ruminal fluid adapted to GL2 and GL3. The ruminal fluid adapted to crude glycerol supplementation increased in vitro methane production when incubating the forage Kikuyu.

Facile Synthesis of Enantiopure Sugar Alcohols: Asymmetric Hydrogenation and Dynamic Kinetic Resolution Combined.

An unprecedented Ir/f-amphox-catalyzed asymmetric hydrogenation of racemic 2,3-syn-dihydroxy-1,4-diones is presented involving dynamic kinetic resolution, which produces (1R,2R,3R,4R)-tetraols. This protocol constitutes an efficient and straightforward approach to accessing sugar alcohols bearing four contiguous stereocenters. The strategy exhibits various advantages over existing methods, including excellent yields (up to 98 %), exceptional stereoselectivities (up to 99:1 dr, 99.9 % ee), operational simplicity and substrate generality. Moreover, the nature of the reaction was revealed as a stepwise transformation by in situ Fourier-transform infrared spectroscopy and isolation of intermediates.

Natural Alternative Sweeteners and Diabetes Management.

PURPOSE OF REVIEW: The goal of this review is to discuss the data on natural alternative sweeteners and their effects on glucose homeostasis and other metabolic parameters within the past five years. We sought to answer whether common natural alternative sweeteners have a positive or negative effect on glucose control in both human and animal models, and whether the data supports their widespread use as a tool to help reduce the prevalence of diabetes and associated comorbid conditions. RECENT FINDINGS: Recent studies suggest that natural alternative sweeteners may reduce hyperglycemia, improve lipid metabolism, and have antioxidant effects particularly in those that have baseline diabetes. Diabetes and metabolic syndrome have become a global healthcare crisis and the sugar overconsumption plays a major role. The use of artificial sweeteners has become more prevalent to improve insulin resistance in those with diabetes, obesity, and metabolic syndrome, although the evidence does not support this result. There are however some promising data to suggest that natural alternative sweeteners may be a better alternative to sugar and artificial sweeteners.

In silico screening of sugar alcohol compounds to inhibit viral matrix protein VP40 of Ebola virus.

Ebola virus is a virulent pathogen that causes highly lethal hemorrhagic fever in human and non-human species. The rapid growth of this virus infection has made the scenario increasingly complicated to control the disease. Receptor viral matrix protein (VP40) is highly responsible for the replication and budding of progeny virus. The binding of RNA to VP40 could be the crucial factor for the successful lifecycle of the Ebola virus. In this study, we aimed to identify the potential drug that could inhibit VP40. Sugar alcohols were enrich with antiviral properties used to inhibit VP40. Virtual screening analysis was perform for the 48 sugar alcohol compounds, of which the following three compounds show the best binding affinity: Sorbitol, Mannitol and Galactitol. To understand the perfect binding orientation and the strength of non-bonded interactions, individual molecular docking studies were perform for the best hits. Further molecular dynamics studies were conduct to analyze the efficacy between the protein-ligand complexes and it was identify that Sorbitol obtains the highest efficacy. The best-screened compounds obtained drug-like property and were less toxic, which could be use as a potential lead compound to develop anti-Ebola drugs.

Ultrasound-Assisted Osmotic Dehydration of Apples in Polyols and Dihydroxyacetone (DHA) Solutions.

The aim of this work was to analyse the effect of ultrasound-assisted osmotic dehydration of apples v. Elise on mass transfer parameters, water activity, and colour changes. Ultrasound treatment was performed at a frequency of 21 kHz with a temperature of 40 °C for 30-180 min using four osmotic solutions: 30% concentrated syrups of erythritol, xylitol, maltitol, and dihydroxyacetone (DHA). The efficiency of the used solutes from the polyol groups was compared to reference dehydration in 50% concentrated sucrose solution. Peleg's model was used to fit experimental data. Erythritol, xylitol, and DHA solutions showed similar efficiency to sucrose and good water removal properties in compared values of true water loss. The application of ultrasound by two methods was in most cases unnoticeable and weaker than was expected. On the other hand, sonication by the continuous method allowed for a significant reduction in water activity in apple tissue in all tested solutions.

Erythritol as sweetener-wherefrom and whereto?

Erythritol is a naturally abundant sweetener gaining more and more importance especially within the food industry. It is widely used as sweetener in calorie-reduced food, candies, or bakery products. In research focusing on sugar alternatives, erythritol is a key issue due to its, compared to other polyols, challenging production. It cannot be chemically synthesized in a commercially worthwhile way resulting in a switch to biotechnological production. In this area, research efforts have been made to improve concentration, productivity, and yield. This mini review will give an overview on the attempts to improve erythritol production as well as their development over time.

[Food intolerances caused by enzyme defects and carbohydrate malassimiliations : Lactose intolerance and Co]. / Lebensmittelunverträglichkeiten durch Enzymdefekte und Zuckerverwertungsstörungen : Laktoseintoleranz und Co.

Apart from allergic conditions, carbohydrate malassimiliations (sugar metabolism disorders) are classified within the group of food intolerances. These dose-dependent, yet non-immunological reactions require gastroenterological or internal diagnosis following nutritional therapy. Intolerances to carbohydrates such as lactose (milk sugar) and fructose (fruit sugar) in addition to sugar alcohols (sorbitol, mannitol, lactitol etc.) have been gaining increasing attention in recent decades as they are the cause of a wide range of gastrointestinal symptoms. There are currently various options for both diagnosis and therapy that differ notably in terms of effort, costs, and efficiency. Nutritional change and patient education are the bases of therapy. Non-observance of the trigger will result in increasing complaints and possibly even more infections, e.g., diverticula, rectal disorders, bacterial miscolonization, bile acid malabsorption). For an optimal therapy, the following sugar metabolism disorders have to be differentiated: hypolactasia versus lactose maldigestion, fructose malabsorption versus fructose overload, combined lactose and fructose intolerance, and isolated adverse reactions against sorbitol.For the medical conditions listed above, a three- or four-stage treatment regimen is recommended. Extensive dietary restrictions with regard to the relevant sugar, except for lactose, should not be maintained over a longer period of time.

Formose reaction controlled by boronic acid compounds.

Formose reactions were carried out in the presence of low molecular weight and macromolecular boronic acid compounds, i.e., sodium phenylboronate (SPB) and a copolymer of sodium 4-vinylphenylboronate with sodium 4-styrenesulfonate (pVPB/NaSS), respectively. The boronic acid compounds provided different selectivities; sugars of a small carbon number were formed favorably in the presence of SPB, whereas sugar alcohols of a larger carbon number were formed preferably in the presence of pVPB/NaSS.

Impact of fillers on dissolution kinetic of fenofibrate dry foams.

Dry foam technology reveals the opportunity to improve the dissolution behavior of poorly soluble drugs tending to agglomeration due to micronization. In this study, the impact of fillers on the manufacturability, the properties of dry foams and granules as well as the dissolution kinetics of dry foam tablets was investigated using fenofibrate as a model compound. Different maltodextrins and dried glucose syrups, a maltodextrin-phosphatidylcholine complex, isomalt and a 1:1 mixture of mannitol/glucose syrup were used as filler. Within the group of maltodextrins and glucose syrups, the influences of dextrose equivalent (DE), particle morphology and botanical source of starch were investigated. Comparable macroscopic foam structures were obtained with maltodextrins and glucose syrups whereas different foam morphologies were obtained for the other fillers tested. Regarding the maltodextrins and glucose syrups, different physicochemical and particle properties had a minor impact on granule characteristics and tablet dissolution. Using the maltodextrin-phosphatidylcholine complex resulted in a low specific surface area of the granules and a slow tablet dissolution caused by a slow disintegration. In contrast, a high specific surface area and a fast release were obtained with isomalt and glucose syrup/mannitol mixture indicating that high soluble low molecular weight fillers enable the development of fast dissolving dry foam tablets.

Hydrodeoxygenation of vicinal OH groups over heterogeneous rhenium catalyst promoted by palladium and ceria support.

Heterogeneous ReOx-Pd/CeO2 catalyst showed excellent performance for simultaneous hydrodeoxygenation of vicinal OH groups. High yield (>99%), turnover frequency (300 h(-1)), and turnover number (10,000) are achieved in the reaction of 1,4-anhydroerythritol to tetrahydrofuran. This catalyst can be applied to sugar alcohols, and mono-alcohols and diols are obtained in high yields (≥85%) from substrates with even and odd numbers of OH groups, respectively. The high catalytic performance of ReOx-Pd/CeO2 can be assigned to rhenium species with +4 or +5 valence state, and the formation of this species is promoted by H2/Pd and the ceria support.

In vivo assessment by Mach-Zehnder double-beam interferometry of the invasive force exerted by the Asian soybean rust fungus (Phakopsora pachyrhizi).

Asian soybean rust (Phakopsora pachyrhizi) causes a devastating disease in soybean (Glycine max). We tested the hypothesis that the fungus generates high turgor pressure in its hyaline appressoria to mechanically pierce epidermal cells. Turgor pressure was determined by a microscopic technique, called transmitted light double-beam interference Mach-Zehnder microscopy (MZM), which was developed in the 1960s as a forefront of live cell imaging. We revitalized some original microscopes and equipped them for modern image capturing. MZM data were corroborated by cytorrhysis experiments. Incipient cytorrhysis determined the turgor pressure in appressoria of P. pachyrhizi to be equivalent to 5.13 MPa. MZM data revealed that osmotically active sugar alcohols only accounted for 75% of this value. Despite having a lower turgor pressure, hyaline rust appressoria were able to penetrate non-biodegradable polytetrafluoroethylene (PTFE) membranes more efficiently than do melanized appressoria of the anthracnose fungus Colletotrichum graminicola or the rice blast fungus Magnaporthe oryzae. Our findings challenge the hypotheses that force-based penetration is a specific hallmark of fungi differentiating melanized appressoria and that this turgor-driven process is solely caused by metabolic degradation products. The appressorial turgor pressure may explain the capability of P. pachyrhizi to forcefully invade a wide range of different plants and may pave the way to novel plant protection approaches.