Effects of cluster dextrin encapsulation on the properties and antioxidant stability of fractionated Riceberry protein hydrolysate powder prepared by bromelain

In this work, the biological properties of fractionated Riceberry bran protein hydrolysate obtained by ultrafiltration (URBPH) were evaluated and the possibility of using cluster dextrin to produce hydrolysate powder by spray-drying was investigated. Fractionation into peptides < 3 kDa was observed to improve antioxidant activity. URBPH < 3 kDa was then freeze-dried (FD-URBPH) and spray-dried (SD-URBPH) at different inlet air temperatures of 100-160 °C. The water solubility and antioxidant activity of FD-URBPH were higher than those of SD-URBPH. Nevertheless, encapsulation of hydrolysate with 10% cluster dextrin and an inlet temperature of 120 °C was also successful in maintaining protein qualities, which showed high 2,2'-azino-bis 3-ethylbenzthiazoline-6-sulfonic (ABTS•+) scavenging activity (89.14%) and water solubility index (92.49%) and low water activity (aw = 0.53). Moreover, encapsulation preserved the antioxidant activity of peptides during gastrointestinal digestion better than the free form. URBPH and its spray-dried microcapsules could be used as bioactive ingredients in functional drinks or foods.

NIR-Active Gold Dogbone Nanorattles Impregnated in Cationic Dextrin Nanoparticles for Cancer Nanotheranostics

Theranostic systems, which integrate therapy and diagnosis into a single platform, have gained significant attention as a promising approach for noninvasive cancer treatment. The field of image-guided therapy has revolutionized real-time tumor detection, and within this domain, plasmonic nanostructures have garnered significant attention. These structures possess unique localized surface plasmon resonance (LSPR), allowing for enhanced absorption in the near-infrared (NIR) range. By leveraging the heat generated from plasmonic nanoparticles upon NIR irradiation, target cancer cells can be effectively eradicated. This study introduces a plasmonic gold dogbone-nanorattle (AuDB NRT) structure that exhibits broad absorption in the NIR region and demonstrates a photothermal conversion efficiency of 35.29%. When exposed to an NIR laser, the AuDB NRTs generate heat, achieving a maximum temperature rise of 38 °C at a concentration of 200 μg/mL and a laser power density of 3 W/cm2. Additionally, the AuDB NRTs possess intrinsic electromagnetic hotspots that amplify the signal of a Raman reporter molecule, making them an excellent probe for surface-enhanced Raman scattering-based bioimaging of cancer cells. To improve the biocompatibility of the nanorattles, the AuDB NRTs were conjugated with mPEG-thiol and successfully encapsulated into cationic dextrin nanoparticles (CD NPs). Biocompatibility tests were performed on HEK 293 A and MCF-7 cell lines, revealing high cell viability when exposed to AuDB NRT-CD NPs. Remarkably, even at a low laser power density of 1 W/cm2, the application of the NIR laser resulted in a remarkable 80% cell death in cells treated with a nanocomposite concentration of 100 μg/mL. Further investigation elucidated that the cell death induced by photothermal heat followed an apoptotic mechanism. Overall, our findings highlight the significant potential of the prepared nanocomposite for cancer theranostics, combining effective photothermal therapy along with the ability to image cancer cells.

Effects of Soluble Dextrin Fiber from Potato Starch on Body Weight and Associated Gut Dysbiosis Are Evident in Western Diet-Fed Mice but Not in Overweight/Obese Children

BACKGROUND

The study investigated the impact of starch degradation products (SDexF) as prebiotics on obesity management in mice and overweight/obese children.

METHODS

A total of 48 mice on a normal diet (ND) and 48 on a Western diet (WD) were divided into subgroups with or without 5% SDexF supplementation for 28 weeks. In a human study, 100 overweight/obese children were randomly assigned to prebiotic and control groups, consuming fruit and vegetable mousse with or without 10 g of SDexF for 24 weeks. Stool samples were analyzed for microbiota using 16S rRNA gene sequencing, and short-chain fatty acids (SCFA) and amino acids (AA) were assessed.

RESULTS

Results showed SDexF slowed weight gain in female mice on both diets but only temporarily in males. It altered bacterial diversity and specific taxa abundances in mouse feces. In humans, SDexF did not influence weight loss or gut microbiota composition, showing minimal changes in individual taxa. The anti-obesity effect observed in mice with WD-induced obesity was not replicated in children undergoing a weight-loss program.

CONCLUSIONS

SDexF exhibited sex-specific effects in mice but did not impact weight loss or microbiota composition in overweight/obese children.

Preliminary assessment of environmental safety (ecosafety) of dextrin-based nanosponges for environmental applications

The ability to employ waste products, such as vegetable scraps, as raw materials for the synthesis of new promising adsorbing materials is at the base of the circular economy and end of waste concepts. Dextrin-based nanosponges (D_NS), both cyclodextrin (CD) and maltodextrin (MD), have shown remarkable adsorption abilities in the removal of toxic compounds from water and wastewater, thus representing a bio-based low-cost solution which is establishing itself in the market. Nevertheless, their environmental safety for either aquatic or terrestrial organisms has been overlooked, raising concern in terms of potential hazards to natural ecosystems. Here, the environmental safety (ecosafety) of six newly synthesized batches of D_NS was determined along with their full characterization by means of dynamic light scattering (DLS), thermogravimetric analysis (TGA), Fourier transformed infrared spectroscopy with attenuated total reflection (FTIR-ATR) and transmission electron microscopy (SEM). Ecotoxicity evaluation was performed using a battery of model organisms and ecotoxicity assays, such as the microalgae growth inhibition test using the freshwater Raphidocelis subcapitata and the marine diatom Dunaliella tertiolecta, regeneration assay using the freshwater cnidarian Hydra vulgaris and immobilization assay with the marine brine shrimp Artemia franciscana. Impact on seedling germination of a terrestrial plant of commercial interest, Cucurbita pepo was also investigated. Ecotoxicity data showed mild to low toxicity of the six batches, up to 1 mg/mL, in the following order: R. subcapitata > H. vulgaris > D. tertiolecta > A. franciscana > C. pepo. The only exception was represented by one batch (NS-Q+_BDE_(GLU2) which resulted highly toxic for both freshwater species, R. subcapitata and H. vulgaris. Those criticalities were solved with the synthesis of a fresh new batch and were hence attributed to the single synthesis and not to the specific D_NS formulation. No effect on germination of pumpkin but rather more a stimulative effect was observed. To our knowledge this is the first evaluation of the environmental safety of D_ NS. As such we emphasize that current formulations and exposure levels in the range of mg/mL do not harm aquatic and terrestrial species thus representing an ecosafe solution also for environmental applications.

Biodegradable Dextrin-Based Microgels for Slow Release of Dual Fertilizers for Sustainable Agriculture

In this research, we report dextrin-based biodegradable microgels (PDXE MGs) having phosphate-based cross-linking units for slow release of urea and a potential P source to improve fertilization. PDXE MGs (∼200 nm) are synthesized by cross-linking the lauroyl-functionalized dextrin chains with sodium tripolyphosphate. The developed PDXE MGs exhibit high loading (∼10%) and encapsulation efficiency (∼88%) for urea. It is observed that functionalization of PDXE MGs with lauroyl chains slows down the release of urea (90% in ∼24 days) as compared to nonfunctionalized microgels (PDX MGs) (99% in ∼17 days) in water. Further studies of the developed formulation display that Urea@PDXE MGs significantly boost maize seed germination and overall plant growth as compared to pure urea fertilizer. Moreover, analysis of maize leaves obtained from plants treated with Urea@PDXE MGs reveals 3.5 ± 0.3% nitrogen content and 90 ± 0.7 mg/g chlorophyll content. These values are significantly higher than 1.4 ± 0.6% nitrogen content and 48 ± 0.05 mg/g chlorophyll content obtained by using bare urea. Further, acid phosphatase activity in roots is reduced upon treatment with PDXE MGs and Urea@PDXE MGs, suggesting the availability of P upon degradation of PDXE MGs by the amylase enzyme in soil. These experimental results present the developed microgel-based biodegradable formulation with a slow release feature as a potential candidate to move toward sustainable agriculture practices.

Characterization of molar mass and conformation of relevant (non-)starch polysaccharides in cereal-based beverages

Arabinoxylans, β-glucans, and dextrins influence the brewing industry's filtration process and product quality. Despite their relevance, only a maximum concentration of β-glucans is recommended. Nevertheless, filtration problems are still present, indicating that although the chemical concentration is essential, other parameters should be investigated. Molar mass and conformation are important polymer physical characteristics often neglected in this industry. Therefore, this research proposes an approach to physically characterize enzymatically isolated beer polysaccharides by asymmetrical flow field-flow fractionation coupled to multi-angle light scattering and differential refractive index detector. Based on the obtained molar masses, root-mean-square radius (rrms from MALS), and hydrodynamic radius (rhyd), conformational properties such as apparent density (ρapp) and rrms/rhyd can be calculated based on their molar mass and size. Consequently, the ρapp and rrms/rhyd behavior hints at the different structures within each polysaccharide. The rrms/rhyd 1.2 and high ρapp values on low molar mass dextrins (1-2·105 g/mol) indicate branches, while aggregated structures at high molar masses on arabinoxylans and β-glucans (2·105 -6·106 g/mol) are due to an increase of ρapp and a rrms/rhyd (0.6-1). This methodology provides a new perspective to analyze starch and non-starch polysaccharides in cereal-based beverages since different physical characteristics could influence beer's filtration and sensory characteristics.

Intersubunit communication in glycogen phosphorylase influences substrate recognition at the catalytic sites

Glycogen phosphorylase (GP) is biologically active as a dimer of identical subunits, each activated by phosphorylation of the serine-14 residue. GP exists in three interconvertible forms, namely GPa (di-phosphorylated form), GPab (mono-phosphorylated form), and GPb (non-phosphorylated form); however, information on GPab remains scarce. Given the prevailing view that the two GP subunits collaboratively determine their catalytic characteristics, it is essential to conduct GPab characterization to gain a comprehensive understanding of glycogenolysis regulation. Thus, in the present study, we prepared rabbit muscle GPab from GPb, using phosphorylase kinase as the catalyst, and identified it using a nonradioactive phosphate-affinity gel electrophoresis method. Compared with the half-half GPa/GPb mixture, the as-prepared GPab showed a unique AMP-binding affinity. To further investigate the intersubunit communication in GP, its catalytic site was probed using pyridylaminated-maltohexaose (a maltooligosaccharide-based substrate comprising the essential dextrin structure for GP; abbreviated as PA-0) and a series of specifically modified PA-0 derivatives (substrate analogs lacking part of the essential dextrin structure). By comparing the initial reaction rates toward the PA-0 derivative (Vderivative) and PA-0 (VPA-0), we demonstrated that the Vderivative/VPA-0 ratio for GPab was significantly different from that for the half-half GPa/GPb mixture. This result indicates that the interaction between the two GP subunits significantly influences substrate recognition at the catalytic sites, thereby providing GPab its unique substrate recognition profile.

Determination of Atropine by HPLC in Plant of Datura by Liquid-Liquid Extraction and Magnet Solid-Phase Extraction

Atropine is a tropane alkaloid found in abundance in Datura plant. We used two liquid-liquid extraction methods and magnet solid-phase extraction to compare the amount of atropine in these two types of plants (Datura innoxia and Datura stramonium). The surface magnetic nanoparticle Fe3O4 correction with an amine and dextrin, and finally, magnetic solid-phase extraction Fe3O4@SiO2-NH2-dextrin (MNPs-dextrin), was prepared. We determined the effect of significant parameters in the removal step and optimization of atropine measurements with half-fractional factorial design (25-1) and response surface methodology via central composite design. The optimum conditions are for desorption solvent = 0.5 mL methanol and desorption time of 5 min. We obtained an extraction recovery of 87.63% with a relative standard deviation of 4.73% via six frequented measurements on a 1 μg L-1 atropine standard solution based on the optimum condition. Preconcentration factors for MNPs are 81, limit of detection = 0.76 μg L-1 and limit of quantitation = 2.5 μg L-1.

Electroconductive bioplatform based on dextrin for the immobilization of hemoglobin: Application for electrochemical monitoring of H2O2

A novel biodegradable dextrin-based nanocomposite, involving polypyrrole (PPy) and hydrophilic dextrin (Dex) (PPy@Dex) was prepared using in-situ radical chemical polymerization technique. The obtained PPy@Dex bionanocomposite was fully characterized by FT-IR, XRD, FESEM, and DSC methods. The exceptional properties such as biocompatibility, high surface area, the proper functional group on the surface, and outstanding electrical conductivity of synthesized bionanocomposite made it a superior candidate over biomolecules immobilization. Electrochemical observations revealed that the PPy@Dex-coated glassy carbon electrode (GCE) demonstrated improved performance, making it a suitable substrate for immobilizing hemoglobin (Hb) and constructing an efficient biosensor. The resulting biosensor, named Hb-PPy@Dex/GCE, exhibited high activity in the reduction of hydrogen peroxide (H2O2). Amperometric examinations demonstrated an extensive linear range from 2 to 350 μM for Hb-PPy@Dex/GCE. The detection limit of the proposed approach was calculated to be 0.54 μM, following the S/N = 3 protocol.

Ex Vivo Colonic Fermentation of NUTRIOSE® Exerts Immuno-Modulatory Properties and Strong Anti-Inflammatory Effects

NUTRIOSE® (Roquette, Lestrem, France) is a resistant dextrin with well-established prebiotic effects. This study evaluated the indirect effects of pre-digested NUTRIOSE® on host immune response and gut barrier integrity. Fecal samples from eight healthy donors were inoculated in a Colon-on-a-plate® system (ProDigest, Ghent, Belgium) with or without NUTRIOSE® supplementation. Following 48 h fermentation, colonic suspensions were tested in a Caco-2/THP1-Blue™ co-culture system to determine their effects on gut barrier activity (transepithelial electrical resistance) and immune response following lipopolysaccharide stimulation. Additionally, changes in short-chain fatty acid levels (SCFA) and microbial community composition following a 48 h fermentation in the Colon-on-a-plate® system were measured. Across all donors, immune-mediated intestinal barrier damage was significantly reduced with NUTRIOSE®-supplemented colonic suspensions versus blank. Additionally, IL-6 and IL-10 levels were significantly increased, and the level of the neutrophil chemoattractant IL-8 was significantly decreased with NUTRIOSE®-supplemented colonic suspensions versus blank in the co-culture models following lipopolysaccharide stimulation. These beneficial effects of NUTRIOSE® supplementation were likely due to increased acetate and propionate levels and the enrichment of SCFA-producing bacteria. NUTRIOSE® was well fermented by the colonic bacteria of all eight donors and had protective effects on inflammation-induced disruption of the intestinal epithelial barrier and strong anti-inflammatory effects.

Study on enteral nutrient components causing decreased gastric phenytoin absorption

BACKGROUND

Previously, we revealed that coadministration of particular enteral nutrients (ENs) decreases plasma concentrations and gastric absorption of phenytoin (PHT), an antiepileptic drug, in rats; however, the mechanism has not been clarified.

METHODS

We measured the permeability rate of PHT using a Caco-2 cell monolayer as a human intestinal absorption model with casein, soy protein, simulated gastrointestinal digested casein protein (G-casein or P-casein) or simulated gastrointestinal digested soy protein (G-soy or P-soy), dextrin, sucrose, degraded guar gum, indigestible dextrin, calcium, and magnesium, which are abundant in the ENs, and measured the solution's properties.

RESULTS

We demonstrated that casein (40 mg/ml), G-soy or P-soy (10 mg/ml), and dextrin (100 mg/ml) significantly decreased the permeability rate of PHT compared with the control. By contrast, G-casein or P-casein significantly increased the permeability rate of PHT. We also found that the PHT binding rate to casein 40 mg/ml was 90%. Furthermore, casein 40 mg/ml and dextrin 100 mg/ml have high viscosity. Moreover, G-casein and P-casein significantly decreased the transepithelial electrical resistance of Caco-2 cell monolayers compared with casein and the control.

CONCLUSION

Casein, digested soy protein, and dextrin decreased the gastric absorption of PHT. However, digested casein decreased PHT absorption by reducing the strength of tight junctions. The composition of ENs may affect the absorption of PHT differently, and these findings would aid in the selection of ENs for orally administered PHT.

Binding Specificity of a Novel Cyclo/Maltodextrin-Binding Protein and Its Role in the Cyclodextrin ABC Importer System from Thermoanaerobacterales

Extracellular synthesis of functional cyclodextrins (CDs) as intermediates of starch assimilation is a convenient microbial adaptation to sequester substrates, increase the half-life of the carbon source, carry bioactive compounds, and alleviate chemical toxicity through the formation of CD-guest complexes. Bacteria encoding the four steps of the carbohydrate metabolism pathway via cyclodextrins (CM-CD) actively internalize CDs across the microbial membrane via a putative type I ATP-dependent ABC sugar importer system, MdxEFG-(X/MsmX). While the first step of the CM-CD pathway encompasses extracellular starch-active cyclomaltodextrin glucanotransferases (CGTases) to synthesize linear dextrins and CDs, it is the ABC importer system in the second step that is the critical factor in determining which molecules from the CGTase activity will be internalized by the cell. Here, structure-function relationship studies of the cyclo⁄maltodextrin-binding protein MdxE of the MdxEFG-MsmX importer system from Thermoanaerobacter mathranii subsp. mathranii A3 are presented. Calorimetric and fluorescence studies of recombinant MdxE using linear dextrins and CDs showed that although MdxE binds linear dextrins and CDs with high affinity, the open-to-closed conformational change is solely observed after α- and β-CD binding, suggesting that the CM-CD pathway from Thermoanaerobacterales is exclusive for cellular internalization of these molecules. Structural analysis of MdxE coupled with docking simulations showed an overall architecture typically found in sugar-binding proteins (SBPs) that comprised two N- and C-domains linked by three small hinge regions, including the conserved aromatic triad Tyr193/Trp269/Trp378 in the C-domain and Phe87 in the N-domain involved in CD recognition and stabilization. Structural bioinformatic analysis of the entire MdxFG-MsmX importer system provided further insights into the binding, internalization, and delivery mechanisms of CDs. Hence, while the MdxE-CD complex couples to the permease subunits MdxFG to deliver the CD into the transmembrane channel, the dimerization of the cytoplasmatic promiscuous ATPase MsmX triggers active transport into the cytoplasm. This research provides the first results on a novel thermofunctional SBP and its role in the internalization of CDs in extremely thermophilic bacteria.

Physicochemical stability, antioxidant activity, and antimicrobial activity of quercetin-loaded zein nanoparticles coated with dextrin-modified anionic polysaccharides

Core-shell biopolymer nanoparticles are assembled from a hydrophobic protein (zein) core and a hydrophilic polysaccharide (carboxymethyl dextrin) shell. The nanoparticles were shown to have good stability and the ability to protect quercetin from chemical degradation under long-term storage, pasteurization, and UV irradiation. Spectroscopy analysis shows that electrostatic, hydrogen bonding, and hydrophobic interactions are the main driving forces for the formation of composite nanoparticles. Quercetin coated with nanoparticles significantly enhanced its antioxidant and antibacterial activities and showed good stability and slow release in vitro during simulated gastrointestinal digestion. Furthermore, the encapsulation efficiency of carboxymethyl dextrin-coated zein nanoparticles (81.2%) for quercetin was significantly improved compared with that of zein nanoparticles alone (58.4%). These results indicate that carboxymethyl dextrin-coated zein nanoparticles can significantly improve the bioavailability of hydrophobic nutrient molecules such as quercetin and provide a valuable reference for their application in the field of biological delivery of energy drinks and food.

Fabrication of different adsorbents based on zirconium oxide, graphene oxide, and dextrin for removal of green malachite dye from aqueous solutions

In this study, graphene oxide and amine graphene were studied by binding to dextrin and zirconium oxide nanoparticles as adsorbent nanocomposites to the removal of dye. Identification and characterization of the synthesized materials were examined using FTIR, XRD, SEM, and BET analyses. Adsorption tests between adsorbents and green malachite (MG) dye solution for the synthesized nanocomposites were performed by considering parameters such as contact time, solution pH, and adsorbent dosage. The data indicated that dye removal increased with increasing the amount of adsorbent dosage. Increased dye removal by increasing the adsorbent dosage can be attributed to the increase of availability of the number of active sites. The active adsorption sites are saturated during the adsorption process, by the molecules of the adsorbate and filled over time. The results showed that the synthesized bio-composite had malachite green removal ability from aqueous media.

Efficacy of Phellinus linteus extract on immunity enhancement: A CONSORT-randomized, double-blind, placebo-controlled pilot trial

BACKGROUND

Immunity is a major system that defends the human body from the outside. Recently, interest in foods related to immunity has been increasing.

METHODS

The purpose of this clinical trial was to determine the safety and efficacy of Phellinus linteus (PL) extract in improving immune function. A total of 30 participants were randomly assigned to 3 groups: the PL1000 group (n = 10) took 1000 mg of PL extract and 1000 mg of dextrin per day; the PL2000 group (n = 10) took 2000 mg of PL extract per day; and the placebo group (n = 10) took 2000 mg of dextrin per day. All participants took 2 capsules twice a day for 8 weeks. We measured their natural killer cell activity and cytokine levels in blood before and after consuming the clinical trial food. Variables were also investigated to evaluate safety, such as adverse reactions, vital signs, and abnormal findings. Student t test or the Mann-Whitney U test, a paired t test or the Wilcoxon signed-rank test, a chi-square test, analysis of variance, and Kruskal-Wallis test were conducted according to the characteristics of the data to compare the differences between each group before and after participants ate the clinical trial food.

RESULTS

The natural killer cell activity and interleukin-6 levels of the PL1000 group tended to improve compared to those of the placebo group. Immunoglobulin G1, immunoglobulin G2, and immunoglobulin M levels did not show significant changes, but tended to improve in the PL1000 and PL2000 groups compared to those of the placebo group. Both the Per Protocol and Intention to Treat populations had improved validation parameters. It is safe because no hazards were found in the safety assessment.

CONCLUSION

PL extract can help improve immunity. Evidences to conduct the main clinical trial is secured through this pilot study. A future large-scale main trial will be conducted based on this pilot study results.

Short-Clustered Maltodextrin Activates Ileal Glucose-Sensing and Induces Glucagon-like Peptide 1 Secretion to Ameliorate Glucose Homeostasis in Type 2 Diabetic Mice

Reconstructing molecular structure is an effective approach to attenuating glycemic response to starch. Previously, we rearranged α-1,4 and α-1,6-glycosidic bonds in starch molecules to produce short-clustered maltodextrin (SCMD). The present study revealed that SCMD slowly released glucose until the distal ileum. The activated ileal glucose-sensing enabled SCMD to be a potent inducer for glucagon-like peptide-1 (GLP-1). Furthermore, SCMD was found feasible to serve as the dominant dietary carbohydrate to rescue mice from diabetes. Interestingly, a mixture of normal maltodextrin and resistant dextrin (MD+RD), although it caused an attenuated glycemic response similar to that of SCMD, failed to ameliorate glucose homeostasis because it hardly induced GLP-1 secretion. The serum GLP-1 levels seen in MD+RD-fed mice (5.25 ± 1.51 pmol/L) were significantly lower than those seen in SCMD-fed mice (8.25 ± 2.01 pmol/L, p < 0.05). Further investigation revealed that the beneficial effects of SCMD could be abolished by a GLP-1 receptor (GLP-1R) antagonist. These results identify GLP-1R signaling as a critical contributor to SCMD-exerted health benefits and highlight the role of ileal glucose-sensing in designing dietary carbohydrates.

Regulatory Effect of Isomaltodextrin on a High-Fat Diet Mouse Model with LPS-Induced Low-Grade Chronic Inflammation

This study aimed to identify the effects of isomaltodextrin (IMD) on sustaining the gut integrity and microbiota composition in a high-fat diet (HFD) with a lipopolysaccharide (LPS)-induced low-grade inflammation mouse model. The homeostasis of the immune response is important to reduce the risk of developing metabolic syndromes. The results of this study showed that pre-treatment of IMD at 5% (w/v) suppressed the concentration of endotoxin and pro-inflammatory mediators TNF-α, MCP-1, and IL-6 while increasing the adiponectin level in the plasma. Subsequently, IMD supplementation maintained the structural integrity and intestinal permeability by upregulating the tight junction protein expressions, leading to reducing D-mannitol concentration in the blood. In addition, dysbiosis was observed in mice induced by HFD plus LPS, suggesting that unhealthy dietary factors elicit metabolic endotoxemia and associated dysbiosis to impair the barrier function. However, IMD supplementation was shown to restore the microbial diversity, promote the growth of Bacteroides-Prevotella, and upregulate the related d-glucarate and d-galactarate degradation pathways, together demonstrating the benefits of IMD as a prebiotic able to promote energy homeostasis. Our results also showed that the blood lipid profile and glucose level in the low-grade inflammation mouse model were modulated by IMD. Moreover, IMD supplementation effectively prevented the metabolic disorder and modulated immune responses in inflamed white adipose tissues by inhibiting the macrophage infiltration and restoring the adiponectin, PPAR-γ, and IRS-1 expression. These findings provide strong evidence for IMD to be a potential prebiotic that acts to sustain a healthy gut microbiota composition and barrier function. By protecting against an unhealthy diet-impaired metabolic balance and maintaining immune homeostasis, IMD may affect the development of metabolic disorders.

Improvement of sleep by resistant dextrin prebiotic in type 2 diabetic women coincides with attenuation of metabolic endotoxemia: involvement of gut-brain axis

BACKGROUND

Resistant dextrin, as a prebiotic and functional food, may possess favorable effects in type 2 diabetes. This study was conducted to assess whether supplementation with resistant dextrin can improve sleep and quality of life in obese type 2 diabetic women.

RESULTS

In this randomized controlled trial, female obese type 2 diabetic patients (n = 76) were randomly assigned into intervention group (n = 38) and placebo group (n = 38), and received 10 g day^-1 of resistant dextrin or maltodextrin for a period of 8 weeks, respectively. Sleep quality and quality of life (QOL) were assessed by Pittsburgh Sleep Quality Index (PSQI) and SF-36 health survey, respectively. Fasting blood samples were driven to measure serum bacterial endotoxin, fasting blood sugar, glycosylated hemoglobin (HbA1c), pro-inflammatory/anti-inflammatory biomarkers (IL-18, IL-6, IL-10, TNF-α), and biomarkers of hypothalamic-pituitary-adrenal (HPA) axis function [tryptophan (TRP), adrenocorticotropic hormone (ACTH), kynurenine (KYN), cortisol]. Supplementation with resistant dextrin improved sleep (P < 0.001) and QOL (P < 0.001) significantly. It also caused a significant decrease in levels of endotoxin, HbA1c, IL-18, IL-6, TNF-α and a significant increase in IL-10 levels. Significant and positive correlations were found between endotoxin (r = 0.488, P = 0.003), IL-6 (r = 0.436, P = 0.008), IL-18 (r = 0.475, P = 0.003), cortisol (r = 0.545, P = 0.048), KYN/TRP (r = 0.527, P = 0.001), and PSQI scores.

CONCLUSIONS

It is concluded that resistant dextrin improves sleep and QOL in obese women with type 2 diabetes. Its beneficial effects may be attributed in part to modulation of glycemia, metabolic endotoxemia and subsequently a decrease in biomarkers of inflammation and HPA axis activity. © 2022 Society of Chemical Industry.

Carbohydrate-Active Enzymes of a Novel Halotolerant Alkalihalobacillus Species for Hydrolysis of Starch and Other Algal Polysaccharides

Halotolerant bacteria capable of starch hydrolysis by their amylases will benefit various industries, specifically since the hydrolytic activity of current industrial amylases is inhibited or even absent in salt-rich or alkaline environments. Seeking novel enzymes, we analyzed the entire genome content of a marine bacterium isolated from the gut of sea urchins to compare it against other bacterial genomes. Conditions underlying α-amylase activity were examined in vitro at various salinities (0 to 4%) and temperatures (25°C to 37°C). Genomic analyses revealed the isolated bacterium as a new species of Alkalihalobacillus. Comparative analysis of the contents of carbohydrate-active enzymes revealed various α-amylases, each with its respective carbohydrate-binding module for starch hydrolysis. Functional analysis identified the hydrolysis of starch and the maltooligosaccharides maltose and dextrin into d- and UDP-glucose. The fastest growth and α-amylase production occurred at 3% salinity at a temperature of 30°C. The Alkalihalobacillus sp. consists of exclusive contents of α-amylases and other enzymes that may be valuable in the hydrolysis of the algal polysaccharides cellulose and laminarin. IMPORTANCE Toward the discovery of novel carbohydrate-active enzymes that may be useful in the hydrolysis of starch, we examined a halotolerant bacterial isolate of Alkalihalobacillus sp. regarding its genomic content and conditions underlying the production of active α-amylases. The production of α-amylases was measured in bacterial cultures at relatively high temperature (37°C) and salinity (4%). The Alkalihalobacillus sp. revealed an exclusive content of amylases and other carbohydrate-active enzymes compared to other relevant bacteria. These enzymes may be valuable for the hydrolysis of algal polysaccharides. The enzymatic cascade of the Alkalihalobacillus sp. for starch metabolism allows polysaccharide degradation into monosugars while preventing the accumulation of intermediate inhibitors of maltose or dextrin.

Influence of native cellulose, microcrystalline cellulose and soluble cellodextrin on inhibition of starch digestibility

Cellulose is a major component of dietary fiber and it is proved to influence starch digestibility. The effects of native cellulose (NC), microcrystalline cellulose (MC), soluble cellodextrin (SC) on starch digestion have not been clearly elucidated. In this study, three types of cellulose with representative molecular weights (NC, 422500 Da; MC, 27750 Da; SC, 2202 Da) were prepared and their effects on starch digestion, glucose diffusion, α-amylase and amyloglucosidase activity were compared. The results suggested SC inhibited starch digestibility to a greater degree than those of NC and MC. When addition of SC reached 3 %, rapidly digestible starch proportion decreased from 31.2 % to 11.3 % and resistant starch proportion increased from 15.0 % to 58.0 %. Notably, hindrance effects of SC on glucose diffusion were higher than those of NC and MC. Moreover, SC reduced activity of α-amylase and amyloglucosidase to a larger extent than those of MC and NC. With the effect of starch digestion inhibition, NC, MC and SC could be utilized as functional food ingredients. Especially, the soluble property and the highest starch digestion inhibition ability of SC favors its application in food industry.

The Effect of Corn Dextrin on the Rheological, Tribological, and Aroma Release Properties of a Reduced-Fat Model of Processed Cheese Spread

Low-calorie and low-fat foods have been introduced to the market to fight the increasing incidence of overweightness and obesity. New approaches and high-quality fat replacers may overcome the poor organoleptic properties of such products. A model of processed cheese spread (PCS) was produced as a full-fat version and with three levels of fat reduction (30%, 50%, and 70%). Fat was replaced by water or by corn dextrin (CD), a dietary fiber. Additionally, in the 50% reduced-fat spreads, fat was replaced by various ratios of CD and lactose (100:0, 75:25, 50:50, 25:75, and 0:100). The effect of each formulation was determined by measuring the textural (firmness, stickiness, and spreadability), rheological (flow behavior and oscillating rheology), tribological, and microstructural (cryo-SEM) properties of the samples, as well as the dynamic aroma release of six aroma compounds typically found in cheese. Winter’s critical gel theory was a good approach to characterizing PCS with less instrumental effort and costs: the gel strength and interaction factors correlated very well with the spreadability and lubrication properties of the spreads. CD and fat exhibited similar interaction capacities with the aroma compounds, resulting in a similar release pattern. Overall, the properties of the sample with 50% fat replaced by CD were most similar to those of the full-fat sample. Thus, CD is a promising fat replacer in PCS and, most likely, in other dairy-based emulsions.

Bentonite-based sodium alginate/ dextrin cross-linked poly (acrylic acid) hydrogel nanohybrids for facile removal of paraquat herbicide from aqueous solutions

Removal of hazardous herbicides from the aqueous solution is critical for overcoming health-related issues across the wider population. In the current work, we have prepared sodium alginate (SAlg), dextrin, and acrylic acid (AA) based cross-linked hydrogels, composed of bentonite incorporated in the biocompatible hydrogel matrix. This hydrogel composite can remove highly toxic herbicide paraquat (PQ). As-synthesised hydrogel (SAlg/dextrin-cl-PAA) and hydrogel composite (SAlg/dextrin-cl-PAA/bentonite) were further analysed by infra-red spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and thermogravimetric analysis (TGA/DSC). For the first time, PQ adsorption onto sodium and dextrin-based hydrogel was also evaluated. The measured highest removal capacities were 76.923 and 90.909 mg g^-1 for the SAlg/dextrin-cl-PAA and SAlg/dextrin-cl-PAA/bentonite, respectively. Pseudo-second-order (PSO) and Langmuir isotherm models have shown to be best suited for accurately describing the adsorption mechanism. A thermodynamics study verified that the adsorption of PQ on adsorbents is spontaneous, favourable and exothermic. Moreover, reusability analysis shows that the adsorbents possess good reproducibility even after six successive cycles. The adsorption results demonstrate that the synthesised adsorbents are very efficient for removing herbicides (PQ) from wastewater.

Postsynthesis Self- And Coassembly of Enzymatically Produced Fluorinated Cellodextrins and Cellulose Nanocrystals

The design of new functional materials and devices substantially relies on self-assembly of hierarchical structures. Formation of 2D platelets is known in the enzymatic synthesis of cellulose-like polymers. Here we demonstrate the feasibility of postsynthesis assembly of novel fluorinated cellodextrins. Highly ordered 2D structures of large lateral dimensions, unattainable in the polymerization process, can be formed because of postsynthesis assembly of the cellodextrins. These cellodextrins were also involved in coassembly with cellulose nanocrystals (CNCs) leading to hybrid systems. The hybrid architectures obtained depend on the content of fluorine atoms in the fluorinated cellodextrins. Monofluorinated cellodextrins coassemble with CNCs into a nanoweb, while multifluorinated cellodextrins assemble around the CNCs.

Effect of dextrin on flotation separation and surface properties of chalcopyrite and arsenopyrite

The flotation separation and mechanism of dextrin on chalcopyrite and arsenopyrite surface were investigated using micro-flotation tests, zeta potential measurements, infrared spectroscopy, contact angle measurement and surface adsorption experiments. The micro-flotation test showed that dextrin had obvious inhibitory effect on arsenopyrite flotation, but had no inhibitory effect on chalcopyrite flotation. After treating the surface of arsenopyrite with dextrin, the infrared spectra showed that new characteristic peaks, indicating that chemical adsorption and significant interaction between dextrin and arsenopyrite particles. Zeta potential measurements, contact angle measurement and surface adsorption experiments showed that the selective adsorption of dextrin added a large number of hydrophilic groups to the surface of arsenopyrite, but had little effect on chalcopyrite. In addition, the macromolecular chain structure of dextrin may hinder the attachment of collector molecules to arsenopyrite. The combined effect of these two aspects makes the arsenopyrite treated with dextrin lose its hydrophobicity and enables the separation of chalcopyrite and arsenopyrite.

Optimization of Hydroxypropyl Methylcellulose and Dextrin in Development of Dried Nanosuspension for Poorly Water-Soluble Drug

The purpose of this study is to identify the effects of a stabilizer and matrix former in the development of a celecoxib dried nanosuspension (DNS) for high dissolution rate and drug loading. Tween 80 and Hydroxypropyl Methylcellulose (HPMC) were used as stabilizers in the bead-milling process and dextrin was used as the matrix former in the spray-drying. Various nanosuspensions (NS) were prepared by varying the ratio of HPMC and dextrin, and the physicochemical properties of each formulation were evaluated for particle size, morphology, drug loading, crystallinity, redispersibility, physical stability and dissolution rate. HPMC efficiently stabilized the NS system and reduced the particle size of NS. The mean particle size of the NS with 0.5% HPMC (w/v) was the smallest (248 nm) of all formulations. Dextrin has been shown to inhibit the increase of particle size efficiently, which is known to occur frequently when NS is being solidified. As the dextrin increased in DNS, the dissolution rates of reconstituted NS were significantly improved. However, it was confirmed that more than the necessary amount of dextrin in DNS reduced the dissolution and drug loading. The dissolution of celecoxib in DNS prepared at the ratio (drug:dextrin, 1:2.5) was almost the highest. The dissolution of optimal formulation was 95.8% at 120 min, which was 2.0-fold higher than that of NS dried without dextrin. In conclusion, these results suggest that the formulation based on Tween 80, HPMC and dextrin may be an effective option for DNS to enhance its in vitro dissolution and in vivo oral absorption.

Optimization of Microencapsulation of Human Milk Fat Substitute by Response Surface Methodology

Human milk fat substitutes (HMFS) are rich in polyunsaturated fatty acids which upon microencapsulation, can be used as a source of high quality lipids in infant formula. The response surface methodology (RSM) was employed to optimize the microencapsulation condition of HMFS as a functional product. The microencapsulation efficiency (MEE) of microencapsulated HMFS was investigated with respect to four variables including concentration of soy lecithin (A), ratio of demineralized whey powder to malt dextrin (B), HFMS concentration (C), and homogenizing pressure (D). The optimum conditions for efficient microencapsulation of HMFS by the spray drying technique were determined as follows: the amount of soybean lecithin-0.96%, ratio of desalted whey powder to malt dextrin-2.04:1, oil content-17.37% and homogeneous pressure-0.46MPa. Under these conditions, the MEE was 84.72%, and the basic indices of the microcapsules were good. The structure of the microcapsules, as observed by scanning electron microscopy (SEM), revealed spherical, smooth-surfaced capsules with diameters ranging between 10-50 μm. Compared with HFMS, the peroxide value (POV) and acid value (AV) of the microcapsule were significantly lower during storage indicating that the microencapsulation process increases stability and shelf life. Infrared spectroscopic analyses indicated that HFMS had the same characteristic functional groups as the oil extracted from microcapsules. Simulated in vitro digestion revealed that the microcapsules were digested completely within 2h with maximum lipid absorption rate of 64%. Furthermore, these results advocate the embedding process of HFMS by RSM due to its efficacy.

[Development of a tissue-equivalent magnetic resonance imaging phantom using indigestible dextrin and soluble calcium]

In magnetic resonance imaging (MRI), the ideal phantom should have similar T1 and T2 values to those of organs of interest for measuring the change in signal intensity, contrast ratio and contrast noise ratio. There have been several reports to develop such a phantom using materials with limited availability or complex methods. In this study, we have developed a simple phantom using indigestible dextrin and soluble calcium at 1.5-tesla MRI. The T1 and T2 values have been reduced by dissolving indigestible dextrin and soluble calcium in distilled water. The similar T1 and T2 values to those of organs (i.e., kidney cortex, kidney medulla, liver, spleen, pancreas, bone marrow, uterus myometrium, uterus endometrium, uterus cervix, prostate, brain white matter, and brain gray matter) have been obtained by varying the concentration of indigestible dextrin and soluble calcium. This phantom is easy to develop and has a potential to increase the accuracy of MRI phantom experiments.

Growth performance and metabolic utilization of diets including starch, dextrin, maltose or glucose as carbohydrate source by gilthead sea bream (Sparus aurata) juveniles

The effect of dietary carbohydrate complexity on growth, feed utilization and activity of selected key liver enzymes of intermediary metabolism were studied in gilthead sea bream juveniles. Four isonitrogenous (50% crude protein) and isolipidic (16% crude lipids) diets were formulated to contain 20% of pregelatinized maize starch, dextrin, maltose or glucose. Triplicate groups of fish (117 g initial weight) were fed each diet to near satiation during 6 weeks. No effect of dietary carbohydrate on growth was noticed. Feed efficiency was lower in fish fed the glucose diet than the maltose and dextrin diets. The lowest protein efficiency ratio was observed in fish fed the glucose diet. Six hours after feeding, glycemia was higher in fish fed the glucose diet than the maltose and starch diets. Liver glycogen content was unaffected by dietary carbohydrate complexity. Hepatic glucokinase (GK) activity was higher in fish fed the glucose and the maltose diets, while higher pyruvate kinase (PK) activity was recorded in fish fed the glucose diet than in fish fed the starch diet. Fructose-1,6-bisphosphatase (FBPase) and glucose-6-phosphate dehydrogenase (G6PD) activities were higher in fish fed the starch diet compared to dextrin and glucose diets. Data suggest that dietary glucose and maltose are more effective than complex carbohydrates in enhancing liver glycolytic activity. Dietary glucose also seems to be more effective than starch in depressing liver gluconeogenic and lipogenic activities. Overall, dietary maltose, dextrin or starch was better utilized than glucose as energy source by gilthead sea bream juveniles.

Oxygen consumption and ammonia excretion of black carp (Mylopharyngdon piceus Richardson) and allogynogenetic crucian carp (Carassius auratus gibelio female x Cyprinus carpio male) fed different carbohydrate diets

Oxygen consumption and ammonia excretion of black carp (Mylopharyngdon piceus Richardson) (4.6±0.3 g) and allogynogenetic crucian carp (Carassius auratus gibelio ♀×Cyprinus carpio ♂) (5.7±0.5 g) were examined when fish fed two types of carbohydrate (dextrin and glucose) at two levels (20 and 40%) each. The diets were isonitrogenous (40% dry matter) and isocaloric at 18.5 kJ g(−1) (dry matter) by adjusting the oil content to 10.1 and 1.5%, respectively. In black carp, the interactions between the carbohydrate type and level were found in oxygen consumption at 3 and 6 h and in ammonia excretion at 6 h after feeding. At 20% carbohydrate, no significant difference was observed between dextrin and glucose in oxygen consumption. However, at 40% carbohydrate, oxygen consumption in fish fed glucose was significantly higher than that in fish fed dextrin at 3 and 6 h after feeding. Within the dextrin diets, no significant differences in both oxygen consumption and ammonia excretion were detected between the two carbohydrate levels. Within the glucose diets, however, fish fed 40% glucose showed significantly higher oxygen consumption than those fed 20% glucose at 3 and 6 h after feeding. Ammonia excretion in black carp fed 40% glucose was higher than that in black carp fed 40% dextrin at 6 h and also found higher than those in the other three treatments at 24 h after feeding. The postprandial oxygen consumption and the ammonia excretion in crucian carp fed 40% glucose were the highest, but no significant differences were observed. Our data indicate that the escalation of glucose to 40% in a fish diet results in high oxygen consumption and ammonia excretion in black carp, suggesting that the efficiency of glucose as an energy source for this fish is compromised by the high metabolic expenditure after feeding. Crucian carp, on the other hand, have a better ability to cope with dietary carbohydrates.

To stabilize a transition state

Inspection of the active sites of the many enzymes whose structures are known at high resolution leads to the unsurprising conclusion that an enzyme may provide an environment that exquisitely stabilizes the transition state for an elementary catalytic step that is expected to be difficult. In an effort both to mimic such an environment and to have the opportunity of investigating the thermodynamic and kinetic consequences of juxtaposing polar and non-polar loci in the same molecule, we have synthesized several specifically functionalized alpha-cyclodextrins. One of these is designed to stabilize the trigonal bipyramidal transition state for an in-line displacement at the phosphorus of a phosphate monoester. This cyclodextrin contains three symmetrically disposed ammonium groups on the 'top' (at C-6) of the hydrophobic cavity formed by the hexa-glucose torus and the remaining 15 hydroxy groups are methylated. The thermodynamic consequences of adjacent hydrophobic and hydrogen-bonding and/or electrostatic binding sites are investigated using several charged and uncharged ligands. The feasibility of building host species explicitly to stabilize reaction transition states is discussed.

Molecules involved in the modulation of rapid cell death in Xanthomonas

In earlier studies from this laboratory, Xanthomonas campestris pv. glycines was found to exhibit a nutrition stress-related postexponential rapid cell death (RCD). The RCD was exhibited in protein-rich media but not in starch or other minimal media. This RCD in X. campestris pv. glycines was found to display features similar to those of the programmed cell death (PCD) of eukaryotes. Results of the present study showed that the observed RCD in this organism is both positively and negatively regulated by small molecules. The amino acids glycine and l-alanine as well as the D isomers of valine, methionine, and threonine were found to induce the synthesis of an active caspase-3-like protein that was associated with the onset of RCD. Addition of pyruvate and citrate to the culture medium induced both the synthesis of active caspase-3-like protein and RCD. Higher levels of intracellular accumulation of pyruvate and citrate were also observed under conditions favoring RCD. On the other hand, dextrin and maltose, the hydrolytic products of starch, inhibited the synthesis of the caspase-3-like protein. Addition of glucose and cyclic AMP (cAMP) to the RCD-favoring medium prevented RCD. Glucose, cAMP, caffeine (a known inhibitor of a phosphodiesterase that breaks down cAMP), and forskolin (from the herb Coleus forskholii, known to activate the enzyme adenylate cyclase that forms cAMP) inhibited the caspase enzyme activity in vivo and consequently the RCD process. The addition of glucose and other inhibitors of RCD enhanced intracellular cAMP accumulation. This is the first report demonstrating the involvement of small molecules in the regulation of nutrition stress-related stationary-phase rapid cell death in X. campestris pv. glycines, which is programmed.

Retention of a European pear aroma model mixture using different types of saccharides

Eight types of microcapsules of European pear (La France) aroma model mixture were prepared, and their retained aroma components and sample microstructures (both surface and cross-section) were compared. The La France pear aroma model mixture was prepared by the mixing of hexanal and five kinds of esters. alpha-Cyclodextrin (alpha-CD), gum arabic (GA), soybean soluble polysaccharide (SSPS), and highly branched cyclic dextrin (HBCD) were used as carrier solids, and spray drying and freeze drying comprised the drying methods. The mean particle size of the microcapsules ranged from 8.34 microm for the microcapsules with alpha-CD to 9.67 microm for those with SSPS. The total aroma contents were different depending upon the microencapsulation systems (1.35 g/100 g of microcapsules for the spray-dried microcapsules with HBCD to 14.1 g/100 g of microcapsules for the freeze-dried microcapsules with GA). The microcapsules with alpha-CD and GA were stable against heat treatment (40, 80, or 120 degrees C for 60 min) under nitrogen gas flow.

[Optimization of formulation of Fufang Danshen immediate release tablet by colligation score]

OBJECTIVE

To optimize the formulation of immediate release tablet.

METHOD

The immediate release tablet was prepared by using dry granules. The preparation was optimized by using orthogonal design which took the flow property of granules, the hardness, the disintegrating time and the dissolution rate of the tablet as indices.

RESULT

The optimized formulation contained 40% microcrystalline cellulose, 10% sodium carboxymethyl starch and 15% dextrin. The hardness disintegrating time and T50 of the tablet were 4.5 kg, 3 min, 5 min respectively.

CONCLUSION

It is successful to prepare on immediate release tablet using the optimized formula above.

Control Release Effects of Binders Used in Pills of Traditional Chinese Medicine Herbs

This research investigated the effects of control release of binders that are used in the pills of Chinese herbal medicine, namely, as processed honey, starch paste, beeswax, or mixtures thereof. Aspirin and baicalin were used as the active pharmaceutical ingredients (API). The processed honey was heated to 110 degrees C, 120 degrees C, or 130 degrees C. In these pills, the binders were the only excipients. The pills were prepared by the stir method using a mixer at 80 degrees C without pressure. The differential thermal analysis (DTA) showed that the melting points of aspirin and baicalin were changed by the binders. The Fourier Transform infrared spectra (FT-IR) of aspirin and baicalin suggest that there are different non-covalent molecular interactions between the API and the binders, such as C-H-pi and hydrogen bond interaction. The dissolution profiles indicate that changing the ratio of the binders altered the patterns of dissolution of the API; thus, this ration may be used to control the release of API from the pills.

[The effect of colcichine and iodine-lithium-alpha-dextrin on the phagocytosis of granulocytes and monocytes in patients with familial Mediterranean fever]

Disturbances in the regulation of phagocytic activity of neutrophils and monocytes (PANM) in whole peripheral blood of patients with familial Mediterranean Fever (FMF), which had not received treatment with colchicines, were determined by quantitative flow cytofluorimetry. The effect of iodine-lithium-alpha-dextrin (armenicum) and colchicine on the PANM in the blood of FMF patients was studied in vitro. The intensity of phagocytosis in populations of neutrophils and monocytes in FMF patients (n = 6) during the remission period is higher than that during the FMF attack (n = 6) and higher than in healthy donors (n = 9). The PANM in patients during the FMF attack is higher compared to that in healthy donors. Iodine-lithium-alpha-dextrin (armenicum) and colchicine inhibited the phagocytosis of effector cells in FMF patients in a dose-dependent and time-dependent manner. It was shown that the suppressive effect of the drugs increased with decreasing bacteria/effector cells ratio.

Study of the microencapsulation of camu-camu (Myrciaria dubia) juice

The camu-camu, like many other Amazonian fruits, shows an excellent potential for use due to its high vitamin C content, and the use of these natural resources could result in greater development of the Amazonian region. Few studies have been conducted with this fruit, and such studies are necessary in order to develop the required technology to allow for its utilization, thus avoiding or at least decreasing wastage of such a rich raw material. The principle objective of this study was to develop a process for the microencapsulation of camu-camu juice, optimizing the operational conditions. The processing conditions consisted of blanching at a temperature of 95 +/- 2 degrees C for 2 min, followed by cooling in an ice bath and juice extraction using a brush type depulper. The juice was dried with gum arabic or malt dextrin in a mini-spray dryer using an air entry temperature of between 100-160 degrees C and wall material concentration varying between 5-35%, in accordance with a factorial experimental design. Both the air entry temperature and the amount of wall material, plus the interaction between the two, gave significant positive effects at the level of 5% probability on the yield of juice powder. The optimum conditions for juice yield and vitamin C retention were established as 15% wall material and an air entry temperature of 150 degrees C.

Chronic ethanol consumption exacerbates microcirculatory damage in rat mesentery after reperfusion

Although the negative effect of excessive alcohol consumption on later stressful events has long been recognized, pathophysiological mechanisms are incompletely understood. We examined possible roles of oxygen radicals and glutathione content in mesenteric venules of chronically ethanol-fed rats exposed to ischemia-reperfusion. Changes in microvascular hemodynamics, such as red blood cell (RBC) velocity, leukocyte adherence, and albumin extravasation, were monitored in postcapillary venules by intravital fluorescence microscopy. Chronic ethanol feeding significantly exaggerated the magnitude of the decrease in RBC velocity, the increased number of adherent leukocytes, and increased albumin leakage elicited by 10 min of ischemia followed by 30 min of reperfusion. Oxidative stress in the endothelium of venules monitored by dihydrorhodamine 123 (DHR) fluorescence was more severe in rats fed ethanol chronically. Both superoxide dismutase and N-acetyl-L-cysteine, which is known to increase glutathione content, reduced the ischemia-reperfusion-induced decrease in RBC velocity, the number of adherent leukocytes, and the increase in albumin leakage, as well as oxidative activation of DHR. This suggests that the increased reperfusion-induced microvascular disturbances in the mesenteric venules of rats fed ethanol chronically are significantly correlated with excessive production of oxygen-derived free radicals and decreased glutathione synthesis.

Vascular endothelial growth factor in peritoneal dialysis: a longitudinal follow-up

In a previous study, vascular endothelial growth factor (VEGF) was found to be locally produced in the peritoneal tissue of patients undergoing peritoneal dialysis (PD) who were being treated with glucose-containing PD solutions. Locally produced VEGF (LVEGF) was positively related to the mass transfer area coefficient (MTAC) of creatinine and to glucose absorption, both of which are representative of the peritoneal vascular surface area. It was therefore hypothesized that VEGF is involved in the peritoneal neoangiogenesis found in long-term PD. The aim of the present study was to investigate the time course of peritoneal VEGF levels in PD patients treated with glucose-based PD solutions during longitudinal follow-up. We also studied the effect of the switch to glucose-free PD treatment on VEGF production. Forty standard peritoneal permeability analyses (SPAs) with 3.86% glucose-containing dialysis solution were investigated. The SPAs were performed in 10 PD patients with a median number of three SPAs per patient during a follow-up of 23 months. Duration of PD treatment at the last SPA was 74 months. All patients were initially treated with glucose-containing dialysis solutions. Four patients switched after 114 months of glucose-based PD to glucose-free PD and were followed for 7 months. A PD regimen of icodextrin, glycerol, and amino acid-based dialysis solutions was applied in these patients. Four SPAs were performed per patient in this period. To predict the VEGF dialysate-to-serum ratio (D/S), when diffusion would be the only explanation for the VEGF dialysate concentration, we calculated the power relationship between D/S ratios of serum proteins that are only transported across the peritoneum and the molecular weights of those proteins. The measured VEGF D/S ratio was higher than expected (P <.001) in each observation, pointing to local production of VEGF. LVEGF increased with duration of glucose PD, 11.7 ng/L to 23.45 ng/L (P <.03). LVEGF decreased in all 4 patients undergoing glucose-free PD, from 57.35 ng/L to 23.10 ng/L. A correlation (r = 0.83, P <.001) was found be-tween the differences in MTAC creatinine between the first and last SPA during glucose-based PD and the difference in LVEGF between these observations. A similar correlation was present between the difference in glucose absorption and the difference in LVEGF (r = 0.85, P <.001). This supports a pathogenetic role of high glucose dialysate concentrations in the development of changes in the peritoneum that are found in long-term PD. Treatment with non-glucose-based PD solutions may inhibit further development of these alterations.

Properties and stability of glycerophosphate oxidase isolated from a mutant strain of Aerococcus viridans

The properties of microbial L-alpha-glycerophosphate oxidase (GPO) isolated from a mutant strain of Aerococcus viridans DBM 1509 were estimated. The stability at different temperatures and pH were detected. At 4 degrees C the enzyme lost activity during 15 d, at 20 degrees C and 30 degrees C GPO activity decreased during 30 and 25 h, respectively. The highest stability was measured at - 20 degrees C and pH 9. At 4 degrees C the stability was enhanced by the addition of 0.1 M EDTA or by lyophilization in the presence of dextrin. These conditions allow the prolongation of the low stability of microbial GPO which limited its use, and give the opportunity to increase the stability of other enzymes

Separation of the enantiomers of ibuprofen and its major phase I metabolites in urine using capillary electrophoresis

A capillary electrophoresis method for determination of the enantiomers of ibuprofen and its major phase I metabolites: 2'-hydroxyibuprofen and 2'-carboxyibuprofen in urine samples have been developed. Cyclodextrins and linear dextrins have been investigated as chiral selectors. Simultaneous chiral separation of the enantiomers of ibuprofen, 2'-hydroxyibuprofen and 2'-carboxyibuprofen was obtained using a mixture of dextrin 10 and heptakis (2,3,6-tri-O-methyl)-beta-cyclodextrin in a 2-[N-morpholino]ethanesulphonic acid buffer, pH 5.26. The electroosmotic flow was reversed using hexadimethrine bromide as a buffer additive. The method can be used for the determination of the free enantiomers of ibuprofen, 2'-hydroxyibuprofen and 2'-carboxyibuprofen as well as for the indirect determination of their glucuronic acid conjugates in urine samples.

Selectivity in capillary electrophoresis in the presence of micelles, chiral selectors and non-aqueous media

In addition to high efficiency, short analysis times and small sample volumes, a further attractive feature of capillary electrophoretic techniques is the possibility to achieve, high selectivities. Usually, selectivity control also allows improvement in the resolution. A simple way to enhance the selectivity of capillary electrophoretic separations is to add one or more surfactants above their critical micelle concentration, or in the case of chiral separations to add a chiral selector to the background electrolyte. Because of the dynamic structure of micelles, the aggregation of monomers and size of the micelles can be easily adjusted. This review describes the various type of surfactants used in micellar electrokinetic capillary chromatography, and the chiral selectors employed in enantiomeric separations by capillary electrophoresis. Factors affecting the selectivity are noted. A brief discussion is included of the selectivity enhancement obtainable in non-aqueous media.

Chiral capillary electrophoresis with noncyclic oligo- and polysaccharide chiral selectors

A number of noncyclic oligo- and polysaccharides have been used as chiral additives in capillary electrophoresis (CE). This review offers a broad survey of the types of oligo- and polysaccharides which have been investigated and also some of the conditions developed for the enantioseparation of a wide range of drugs and other racemic compounds. Details of enantioseparation mechanisms are also discussed, in addition to some of the parameters required for optimization of the enantioresolution of chiral molecules.

CARBOHYDRASES OF THE RUMEN CILIATE EPIDINIUM ECAUDATUM (CRAWLEY). HYDROLYSIS OF PLANT HEMICELLULOSE FRACTIONS AND BETA-LINKED GLUCOSE POLYMERS

1. Cell-free extracts from Epidinium ecaudatum (Crawley) hydrolysed the three hemicellulose fractions of pasture plants, but at different rates. 2. All of the constituent monosaccharides are released from the hemicellulose fractions, galactose and uronic acids being liberated at much slower rates than pentoses. 3. An arabinofuranosidase, which removes arabinose from highly branched arabinoxylan before the xylan chain can be hydrolysed, was isolated free from other pentosanases. 4. A xylanase hydrolysing xylan (by random cleavage) and xylodextrins of degree of polymerization (D.P.) > 3 to xylotriose and xylobiose was isolated free from other pentosanases. 5. A separate xylodextrinase hydrolysing (by random cleavage) xylodextrins of D.P. > 2 to xylobiose and xylose was also obtained; this enzyme did not hydrolyse xylan or xylobiose and the original extracts themselves possessed very weak xylobiase activity. 6. The epidinial extracts hydrolysed laminaribiose, laminarin, lichenin and cellodextrins of D.P. < 7 rapidly, cellobiose and gentiobiose slowly but cellulose not at all. 7. Polysaccharide glucose associated with plant linear B hemicellulose was liberated with cellobiose and possibly laminaribiose as intermediates. 8. The cellodextrinase hydrolysed cellopentaose initially to cellobiose plus cellotriose and is a distinctly different enzyme from the xylanase and xylodextrinase. 9. Extracts from Entodinium species and Eremoplastron bovis also hydrolysed all three types of plant hemicellose.

[Nutrition in the first months of life with a new formula containing maltodextrins and enriched with long-chain fatty acids]

According to the recent acquisition about the biochemical properties of the carbohydrates contained in human milk, the addition of maltodextrins to infant formulas became recommended. We refer about the preliminary data of the first utilization of a new formula (Aptamil 1 "Nuova Formula") in which both maltodextrins and Long Chain Fatty Acids are added. Sixty-seven infants were enrolled to the study for the first 4 months of life. Forty-three of them (64%) completed the study and were grouped as follows: Group 1 = 15 subjects exclusively formula-fed (4F, 11M), Group 2 = 21 infants with mixed feeding (breast + formula), Group 3 = 7 cases in which Aptamil 1 "Nuova Formula" substituted another formula (4F, 3M). Auxologic parameters (weight, length, head circumference) were among the normal standard limits according to the percentile charts of the Boston Children's Medical Center. All infants enjoyed the taste of the milk we tested. The food regimen was changed in 4/67 (6%) infants because of alimentary intolerance suspicion but 2/4 infants were subsequently fed with soya milk formula and with an "hypoallergenic" milk respectively, the other 2 continued with another formula. The weight growth chart in infants of Group 1 tended to bend down a little bit between the 3rd and 4th month, reminding the breast-fed infants behavior. Considering the daily milk volume assumed by the same subjects, we found a statistical difference (p < or = 0.01) between the volumes of milk assumed in the 2nd and the 3rd month of life but from the 3rd to the 4th month there was no statistical difference in daily milk volumes. This resembles the breast-fed infants behavior as well. According to our preliminary results the new milk formula we tested seems a very good substitute when an infant can't be breast-fed for any reason.