A high-molecular weight exopolysaccharide from the Cs-HK1 fungus: Ultrasonic degradation, characterization and in vitro fecal fermentation.

This work was to examine the impact of power ultrasound (US) on the molecular properties of a high-molecular weight (MW) exopolysaccharide (EPS) from the Cs-HK1 medicinal fungus and the utilization, and prebiotic function of the US-treated EPS fractions in human fecal microflora in vitro. The US treatment caused notable reduction of intrinsic viscosity, average MW and aggregate size of EPS in water but no significant changes in the molecular structure. The US-treated EPS fractions were consumed more rapidly by the fecal microflora, resulting in a higher total level of short chain fatty acids. They also affected the relative abundance in the microflora more beneficially than the original EPS. The results suggest that power US is effective for modifying and improving the prebiotic properties of high-MW polysaccharides.

5-Keto-D-fructose production from sugar alcohol by isolated wild strain Gluconobacter frateurii CHM 43.

GLUCONOBACTER FRATEURII: CHM 43 have D-mannitol dehydrogenase (quinoprotein glycerol dehydrogenase) and flavoprotein D-fructose dehydrogenase in the membranes. When the two enzymes are functional, D-mannitol is converted to 5-keto-D-fructose with 65% yield when cultivated on D-mannitol. 5-Keto-D-fructose production with almost 100% yield was realized with the resting cells. The method proposed here should give a smart strategy for 5-keto-D-fructose production.

Chemical composition of thermally processed coconut water evaluated by GC-MS, UPLC-HRMS, and NMR.

Thermally-processed coconut water often develop a commercially-undesirable pink color, thus, NMR, UPLC-HRMS, GC-MS analyses combined with chemometrics approach were applied to evaluate chemical variations in comparison to tender water (control) that could explain such color change. Chemometrics on negative ionization mode dataset showed trimeric and A-type dimeric procyanidins, and caffeoylshikimic acid as main identified secondary metabolites induced by processing, while, control water presented mainly cytokinin trans-zeatin riboside, procyanidin dimer, caffeoylshikimic acid and trihydroxy-octadecenoic acid. Processing increased long-chain saturated palmitic and stearic fatty acids contents, meanwhile NMR analysis showed a decline in primary metabolites content as sugars fructose and glucose, and short-chain organic acids. Among the results observed for thermally processed coconut water, the increase in oligomeric procyanidins as A-type dimer and trimer may be associated with pink color development as these are precursors of anthocyanin pigment and/or by enhancing color stability of anthocyanin solutions.

Discrimination of Natural Mature Acacia Honey Based on Multi-Physicochemical Parameters Combined with Chemometric Analysis.

Honey maturity is an important factor in evaluating the quality of honey. We established a method for the identification of natural mature acacia honey with eighteen physicochemical parameters combined with chemometric analysis. The analysis of variance showed significant differences between mature and immature acacia honey in physicochemical parameters. The principal component analysis explained 82.64% of the variance among samples, and indicated that total phenolic content, total protein content, and total sugar (glucose, fructose, sucrose) were the major variables. The cluster analysis and orthogonal partial least squares-discriminant analysis demonstrated that samples were grouped in relation to the maturity coinciding with the results of the principal component analysis. Meanwhile, the 35 test samples were classified with 100% accuracy with the method of multi-physicochemical parameters combined with chemometric analysis. All the results presented above proved the possibility of identifying mature acacia honey and immature acacia honey according to the chemometric analysis based on the multi-physicochemical parameters.

A new isoflavane-4-ol derivative from Melilotus officinalis (L.) Pall.

A new isoflavane derivative, melilofficinaside together with seven other metabolites including coumarin, uridine, methyl-α-d-fructofuranoside, and flavonoid glucosides were isolated from the aerial parts of Melilotus officinalis (L.) Pall.

Rapidly Simultaneous Determination of Six Effective Components in Cistanche tubulosa by Near Infrared Spectroscopy.

Quantitative determination of multiple effective components in a given plant usually requires a very large amount of authentic natural products. In this study, we proposed a rapid and non-destructive method for the simultaneous determination of echinacoside, verbascoside, mannitol, sucrose, glucose and fructose in Cistanche tubulosa by near infrared spectroscopy (NIRS). Near infrared diffuse reflectance spectroscopy (DRS) and high performance liquid chromatography (HPLC) were conducted on 116 batches of C. tubulosa samples. The DRS data were processed using standard normal variety (SNV) and multiplicative scatter correction (MSC) methods. Partial least squares regression (PLSR) was utilized to build calibration models for components-of-interest in C. tubulosa. All models were then assessed by calculating the root mean square error of calibration (RMSEC), correlation coefficient of calibration (r). The r values of all six calibration models were determined to be greater than 0.94, suggesting each model is reliable. Therefore, the quantitative NIR models reported in this study can be qualified to accurately quantify the contents of six medicinal components in C. tubulosa.

Effects of rare sugar d-allulose on heat-induced gelation of surimi prepared from marine fish.

BACKGROUND: d-Allulose (Alu), the C3-epimer of d-fructose, is a non-caloric sweetener (0.39 kcal g-1 ) with a suppressive effect on postprandial blood glucose elevation. The aim of this study was to investigate the effects of Alu used as a sweetener and gel improver instead of sucrose on heat-induced gelation of surimi. RESULTS: The puncture test of a heat-induced surimi gel showed that with 50 g kg-1 Alu the gel had 15% and 6% higher gel strength than the corresponding gel with sucrose (Suc) and with sorbitol (Sor), respectively. In addition, Alu-gel had 26% and 25% higher water-holding capacity (WHC) than Suc- and Sor-gel. Heating of myofibrillar protein with Alu, unlike Suc and Sor, facilitated the formation of both disulfide and non-disulfide crosslinks that might be associated with the mechanical properties and WHC of Alu-gel. CONCLUSION: Alu improves the mechanical properties and WHC of the heat-induced surimi gel. Furthermore, Alu is low in calories compared with Suc (4.0 kcal g-1 ) and Sor (3.0 kcal g-1 ). Thus Alu will be an alternative of Suc or Sor for developing surimi-based products with health benefits. © 2017 Society of Chemical Industry.

13C labeling analysis of sugars by high resolution-mass spectrometry for metabolic flux analysis.

Metabolic flux analysis is particularly complex in plant cells because of highly compartmented metabolism. Analysis of free sugars is interesting because it provides data to define fluxes around hexose, pentose, and triose phosphate pools in different compartment. In this work, we present a method to analyze the isotopomer distribution of free sugars labeled with carbon 13 using a liquid chromatography-high resolution mass spectrometry, without derivatized procedure, adapted for Metabolic flux analysis. Our results showed a good sensitivity, reproducibility and better accuracy to determine isotopic enrichments of free sugars compared to our previous methods [5, 6].

n-Butyl-α-D-fructofuranoside Isolated from Ulmus davidiana Enhances Nrf2 Activity Through Activation of JNK.

BACKGROUND: The root bark of Ulmus davidiana Nakai (Ulmaceae), a traditional Korean medicinal plant, is used for treating inflammatory diseases. OBJECTIVE: We investigated the Nrf2-activating effect of U. davidiana and identified a novel Nrf2 activator from its constituent compounds. METHODS: Cytotoxicity was measured by MTT assay, and the Nrf2 activity was examined by luciferasereporter assay and western blot analysis. The expression of Nrf2-dependent antioxidant genes was estimated by RT-PCR. The signal pathway related to Nrf2 activation was analyzed by treating specific signaling inhibitors. Anti-inflammatory effects were determined using an NO assay and western blot analysis. RESULTS: Ulmus davidiana and its constituent compounds, including catechin-3-O-α-L-rhamnopyranoside, α-nigerose, n-butyl α-D-fructofuranoside (NBF), and procyanidin B3, enhanced the transcriptional activity of Nrf2. Of these compounds, only NBF possessed a distinctive structure and exhibited ROS-independent Nrf2 activation. In addition, NBF significantly increased the nuclear translocation of Nrf2 and the expression of Nrf2-dependent detoxifying enzymes, including HO-1 and NQO-1, in dose-dependent manner. The Nrf2 activation induced by NBF was mediated by the phosphorylation of JNK. Consequently, pretreatment with NBF inhibited the LPS-induced expression of pro-inflammatory genes. CONCLUSION: To the best of our knowledge, this is the first study to report on the Nrf2-activating effect of U. davidiana and NBF. Given the importance of Nrf2 as a negative regulator in various inflammatory diseases, NBF could be considered as a novel candidate for the prevention and treatment of inflammatory diseases.

New Trends and Technological Challenges in the Industrial Production and Purification of Fructo-oligosaccharides.

An increased commercial interest in fructo-oligosaccharides (FOS) has emerged in the last decade due to their prebiotic activity. At large scale, the FOS are produced by microbial enzymes from sucrose. A mixture of FOS and other saccharides is obtained in this process. The presence of such saccharides reduces the prebiotic, caloric, and cariogenic value of the final product. Therefore, many efforts have been conducted to obtain a product with increased FOS purity. This review comprises the most important technological and physicochemical aspects including FOS production and recovery processes; safety, dose and health claims concerning its intake; and commercially available FOS.

Development and validation of a liquid chromatographic method to quantify sucrose, glucose, and fructose in tubers of Solanum tuberosum Group Phureja.

A High Performance Liquid Chromatography (HPLC) method was developed and validated to quantify sucrose (non-reducing sugar), glucose, and fructose (reducing sugars) in raw tubers of Solanum tuberosum Group Phureja. Chromatographic analysis was performed using an AMINEX HPX 87H column, at 18 °C, linked to a refraction index detector, at 35 °C. The eluent was 10mM sulfuric acid. The conditions established for the method provided an optimum separation of sugars, citric acid, and malic acid, with resolution values higher or equal to one. Among the four sugar extraction methods tested, the double 50% (v/v) aqueous methanol extraction gave the highest level of analytes. Recovery of this extraction method ranged between 94.14 and 99.77%. The HPLC method was validated for repeatability, reproducibility, linearity, and limits of detection, and quantification. Relative standard deviation was found to be lower than five, when testing repeatability and reproducibility, which is suitable considering a range of acceptability from 5.3 to 7.3. Additionally, the regression analyses supported the method linearity in a range of quantification from 3 to 100 mg/L with regression coefficients values greater than 0.998 for the three analytes. Limits of detection were 3.0 mg/L for the three sugars and limits of quantification were 2.0 mg/L for sucrose and 3.0 mg/L for glucose and fructose. Four Colombian commercial cultivars (Criolla Guaneña, Criolla Paisa, Criolla Galeras, and Criolla Colombia) and five landrace accessions from the Colombian Core Collection of Group Phureja were grown in the district of Usme (Bogotá) fields to analyze their sugar contents. Sucrose, glucose, and fructose contents were found ranging from 0.93 to 3.11 g/100 g tuber dried weight (DW), from 0.25 to 4.53 g/100 g tuber DW, and from 0.10 to 1.49 g/100 g tuber DW, respectively. Therefore, a high range in the variability of sugar contents was found among genotypes. However, the variability was low among technical replicates of the same genotype, revealing an accurate quantification of sugars in Group Phureja. This method can be used to assess the amount of reducing and non-reducing sugars accumulation in potato germplasm.

Response of gelatin modified electrode towards sensing of different metabolites.

In this study, a very thin film of biocompatible gelatin B (GB) fabricated onto indium tin oxide (ITO)-coated glass substrate for electrochemical catalytic activity towards different metabolites has been investigated. The optical and electrochemical properties of bare GB/ITO electrode and with different metabolites were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and electrochemical techniques. The optical properties clearly indicate the structural and surface morphological changes on electrode surface. FTIR spectra showed displacement of the IR peaks towards smaller wave numbers, indicating possible existence of hydrogen bonding between the GB and metabolites. The catalytic behaviour of GB/ITO electrode towards ascorbic acid (AA), citric acid (CA), oxalic acid (OA), glucose (Glu), sucrose (Suc), lactose (Lac) and fructose (Fru) has been investigated by cyclic voltammetry (CV). The electrochemical response studies of GB/ITO electrode have been monitored with different metabolites in the range of 10-500 mg/dl. The sensitivity of GB/ITO electrode for AA and OA was found as 0.156 and 0.108 µA/(mg/dl cm(-2)) respectively. The results indicate that the GB/ITO electrode has higher specificity towards the AA and OA. The attractive properties of GB/ITO electrode provide the potential applications in the simultaneous detection of AA and OA. The excellent electrocatalytic behaviour of GB/ITO electrode may be useful towards the construction of electrochemical biosensors.

Antiproliferative effects of n-butyl-ß-D-fructofuranoside from Kangaisan on Bel-7402 cells.

AIMS: Kangaisan is a powdered compound prescription of Traditional Chinese Medicine which has been used in cancers for many years in Hubei province, China. The purpose of this study was to investigate the antitumor effects of Kangaisan and screen bioactive components. MATERIALS AND METHODS: 3-(4,5-Dimethythiazol-2-yl)-2,5 diphenyl-tetrazolium bromide (MTT) assay, flow cytometry, DNA (Deoxyribonucleic acid) fragmentation assay, Western blot, and real time-polymerase chain reaction were used to investigate the antiproliferation effect of n-butyl-ß-D-fructofuranoside on Bel-7402 cells. STATISTICAL ANALYSIS: All experiments were performed in triplicate and the results were expressed as mean ± standard deviation. Statistical analysis was performed with analysis of variance using Origin 8.0 software. RESULTS: It was illustrated that treatment of Bel-7402 cells with various concentrations of n-butyl-ß-D-fructofuranoside resulted in growth inhibition in both a dose-dependent and time-dependent manner. The arrest of G0/G1 phase was also induced (P < 0.05). The increasing of sub-G1 cell population indicated the apoplectic characteristic (P < 0.05). Furthermore, the emerging of DNA fragmentation and the increase of Bax/Bcl-2 ratio and p53 expression suggested the possible mitochondrial apoptotic pathway (P < 0.05). CONCLUSIONS: The results illustrate that Kangaisan showed anticancer effects and n-butyl-ß-D-fructofuranoside extracted from Kangaisan can suppress Bel-7402 cells via interfering cell cycle and by inducing apoptosis.

Extracting kinetics from affinity capillary electrophoresis (ACE) data: a new blade for the old tool.

We describe a mathematical approach that enables extraction of kinetic rate constants from thousands of studies conducted over the past two decades with affinity capillary electrophoresis (ACE). Previously, ACE has been used almost exclusively for obtaining equilibrium constants of intermolecular interactions. In this article, we prove that there exists an analytical solution of partial differential equations describing mass transfer in ACE. By using an in silico study, we demonstrate that the solution is applicable to experimental conditions that are typically used in ACE and found in most historical ACE experiments. The solution was validated by extracting rate constants from previously published ACE data and closely matching independently obtained results. Lastly, it was used to obtain previously unknown rate constants from historical ACE data. The new mathematical approach expands the applicability of ACE to a wider range of biomolecular interactions and enables both prospective and retrospective data analysis. The obtained kinetic information will be of significant practical value to the fields of pharmacology and molecular biology.

Fluorescent boronic acid polymer grafted on silica particles for affinity separation of saccharides.

Boronic acid affinity gels are important for effective separation of biological active cis-diols, and are finding applications both in biotech industry and in biomedical research areas. To increase the efficacy of boronate affinity separation, it is interesting to introduce repeating boronic acid units in flexible polymer chains attached on solid materials. In this work, we synthesize polymer brushes containing boronic acid repeating units on silica gels using surface-initiated atom transfer radical polymerization (ATRP). A fluorescent boronic acid monomer is first prepared from an azide-tagged fluorogenic boronic acid and an alkyne-containing acrylate by Cu(I)-catalyzed 1,3-dipolar cycloaddition reaction (the CuAAC click chemistry). The boronic acid monomer is then grafted to the surface of silica gel modified with an ATRP initiator. The obtained composite material contains boronic acid polymer brushes on surface and shows favorable saccharide binding capability under physiological pH conditions, and displays interesting fluorescence intensity change upon binding fructose and glucose. In addition to saccharide binding, the flexible polymer brushes on silica also enable fast separation of a model glycoprotein based on selective boronate affinity interaction. The synthetic approach and the composite functional material developed in this work should open new opportunities for high efficiency detection, separation, and analysis of not only simple saccharides, but also glycopeptides and large glycoproteins.

Structure of fructo-oligosaccharides from leaves and stem of Agave tequilana Weber, var. azul.

Fructo-oligosaccharides (FOSs) of a six year old agave plant variety, Agave tequilana, were isolated and fractionated by 2D preparative chromatography (SEC and rpHPLC). Structural analyses of different FOS-fractions were performed by reductive methylation analysis connected to GC/FID identification and NMR-analysis. FOSs from leaves (d.p. 3-8) contain single α-d-Glcp residues as well in terminal as internal position, however (2→1)-linked ß-d-Fruf residues only. FOSs from stem, however, contain as well (2→1)- and (2→6)-linked ß-d-Fruf residues with branched oligomeric repeating units. These characteristics indicate an enzymatically catalyzed metabolic regulation for the biosynthesis and transformation of fructans in A. tequilana which strongly depends on location and transport activities.

A sensitive capillary GC-MS method for analysis of topiramate from plasma obtained from single-dose studies.

Topiramate (Topamax®) is an antiepileptic medication used as adjunctive and monotherapy in patients with epilepsy and for migraine prophylaxis. A GC-MS assay was developed that was capable of detecting topiramate plasma concentrations following a single rectal or oral dose administration. Topiramate plasma samples were prepared by solid-phase extraction and were quantified by GC-MS analysis. The topiramate standard curves were split from 0.1 to 4 µg/mL and from 4 to 40 µg/mL in order to give a more accurate determination of the topiramate concentration. The accuracy of the standards ranged from 94.6 to 107.3% and the precision (%CV) ranged from 1.0 to 5.3% for both curves at all concentrations. The %CV for quality controls was <7.6%. The assay is both accurate and precise and will be used to complete future pharmacokinetic studies.

Fructo-oligosaccharides purification from a fermentative broth using an activated charcoal column.

In this study, a simple and efficient process to purify fructo-oligosaccharides (FOS) from a fermentative broth was proposed using a single activated charcoal column. The FOS adsorption onto the activated charcoal was modeled by a pseudo-second order model. Several volumes and concentrations of water/ethanol were studied to optimize the selective desorption of sugars from the broth mixture at 25°C. Mixtures containing 50.6% (w/w) of FOS (FOS content in the fermentative broth) were purified to 92.9% (w/w) with a FOS recovery of 74.5% (w/w). Moreover, with the proposed process, fractions with purity up to 97% (w/w) of FOS were obtained. This purification process was also found to be efficient in the desalting of the fermentative broth.

Reduction of fumonisin B1 in corn grits by twin-screw extrusion.

UNLABELLED: This study was designed to investigate the fate of fumonisins in flaking corn grits during twin-screw extrusion by measuring fumonisin B1 (FB1) and its analogs with a mass balance approach. Food grade corn grits and 2 batches of grits contaminated with FB1 at 10 and 50 µg/g by Fusarium verticillioides M-2552 were processed with or without glucose supplementation (10%, w/w) with a twin-screw extruder. Extrusion reduced FB1 in contaminated grits by 64% to 72% without glucose and 89% to 94% with added glucose. In addition, extrusion alone resulted in 26% to 73% reduction in the levels of fumonisin B2 and fumonisin B3, while levels of both mycotoxins were reduced by >89% in extruded corn grits containing 10% glucose. Mass balance analysis showed that 38% to 46% of the FB1 species detected in corn extruded with glucose was N-(deoxy-D-fructos-1-yl)-FB1, while 23% to 37% of FB1 species detected in extruded corn grits with and without added glucose was bound to the matrix. It was also found that the hydrolyzed form of FB1 was a minor species in extruded corn grits with or without added glucose, representing <15% of the total FB1 species present. Less than 46% of FB1 originally present in corn grits could be detected in the fumonisin analogues measured in this study. Research is needed to identify the reaction products resulting from extrusion processing of fumonisin-contaminated corn products. PRACTICAL APPLICATION: Twin-screw extrusion is widely used in food industry for its versatility. This technology may reduce the level of fumonisins in corn particularly with added glucose.

Inhibitory effects of 1-O-methyl-fructofuranose from Schisandra chinensis fruit on melanogenesis in B16F0 melanoma cells.

AIM OF THE STUDY: 1-O-methyl-fructofuranose (1-O-MFF) from the fruit of Schisandra chinensis is a traditional Korean medicinal herb that has a variety of beneficial properties. The effect of purified 1-O-MFF on melanogenesis including the activation of related signaling pathways was investigated. MATERIALS AND METHODS: The inhibitory activities of 1-O-MFF were examined by melanin synthesis, tyrosinase activity assay, Western blot and flow cytometric analyses in B16F0 mouse melanoma cells. RESULTS: 1-O-MFF significantly inhibited both melanin synthesis and tyrosinase activity in a concentration-dependent manner, and reduced the expression of melanogenic proteins including microphthalmia-associated transcription factor (MITF), tyrosinase and tyrosinase-related protein-1. 1-O-MFF phosphorylated and activated melanogenesis inhibitory proteins such as mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) and Akt. Flow cytometry confirmed that 1-O-MFF phosphorylated ERK and Akt proteins and recovered partially phosphorylated forms in cells treated with the MEK/ERK inhibitor compound PD98059 and the phosphatidylinositol 3-kinase (PI3K)/Akt inhibitor compound LY294002. CONCLUSIONS: The suppressive effects of 1-O-MFF on melanogenesis may involve down-regulation of MITF and its downstream signal pathway via the activation of MEK/ERK or PI3K/Akt.