Classification of binding property of amyloid β to lipid membranes: Membranomic research using quartz crystal microbalance combined with the immobilization of lipid planar membranes.

A biomembrane-related fibrillogenesis of Amyloid β from Alzheimer' disease (Aβ) is closely related to its accumulation behavior. A binding property of Aβ peptides from Alzheimer' disease to lipid membranes was then classified by a quartz crystal microbalance (QCM) method combined with an immobilization technique using thiol self-assembled membrane. The accumulated amounts of Aβ, Δf, was determined from the measurement of the maximal frequency reduction using QCM.

Amyloid-β aggregates induced by β-cholesteryl glucose-embedded liposomes.

Senile plaques that is characterized as an amyloid deposition found in Alzheimer's disease are composed primarily of fibrils of an aggregated peptide, amyloid β (Aβ). The ability to monitor senile plaque formation on a neuronal membrane under physiological conditions provides an attractive model. In this study, the growth behavior of amyloid Aβ fibrils in the presence of liposomes incorporating β-cholesteryl-D-glucose (β-CG) was examined using total internal reflection fluorescence microscopy, transmittance electron microscopy, and other spectroscopic methods.

Microfluidic and hydrothermal preparation of vesicles using sorbitan monolaurate/polyoxyethylene (20) sorbitan monolaurate (Span 20/Tween 20).

Here, we present a method for preparing vesicles by combining hydrothermal emulsification with solvent diffusion (SD). The sorbitan monolaurate/polyoxyethylene (20) sorbitan monolaurate (Span 20/Tween 20) system was used as the target lipid because these lipids are cheap and advantageous for the production scale. The water-in-oil (W/O) emulsion stabilized with lipids was formed under hydrothermal conditions (240 °C under 10 MPa), followed by mixing with water that included lipids to obtain a W/O-in-water (W/O/W) emulsion.

Application of liposome membrane as the reaction field: A case study using the Horner-Wadsworth-Emmons reaction.

The properties of the liposome membrane as a reaction field were investigated by focusing on the Horner-Wadsworth-Emmons reaction as a case study. Use of the liposomes existing in the gel phase resulted in the enhanced activity of the substrates and furnished the products with same E/Z stereoselectivity as in the liposome-free system. The membrane environment in the gel phase most likely assisted the formation of adducts that induced selective generation of the E-isomer.

Temperature Measurement by Sublimation Rate as a Process Analytical Technology Tool in Lyophilization.

Product temperature (T) and drying time constitute critical material attributes and process parameters in the lyophilization process and especially during the primary drying stage. In the study, we performed a temperature measurement by the sublimation rate (TMbySR) to monitor the T value and determine the end point of primary drying. First, the water vapor transfer resistance coefficient through the main pipe from the chamber to the condenser (C) was estimated via the water sublimation test.

Effect of Controlled Nucleation of Ice Crystals on the Primary Drying Stage during Lyophilization.

The freezing stage cannot be directly controlled, which leads to variation in product quality and low productivity during the lyophilization process. Our objective was to establish a robust design space for the primary drying stage using ice nucleation control based on the pressurization and depressurization technique. We evaluated the specific surface area (SSA), water content, scanning electron microscopy (SEM) images, and water vapor transfer resistance of the dried layer (R) of the products.

Scale-Up Procedure for Primary Drying Process in Lyophilizer by Using the Vial Heat Transfer and the Drying Resistance.

The objective of this study is to design primary drying conditions in a production lyophilizer based on a pilot lyophilizer. Although the shelf temperature and the chamber pressure need to be designed to maintain the sublimation interface temperature of the formulation below the collapse temperature, it is difficult to utilize a production lyophilizer to optimize cycle parameters for manufacturing. In this report, we assumed that the water vapor transfer resistance (R) in the pilot lyophilizer can be used in the commercial lyophilizer without any correction, under the condition where both lyophilizers were operated in the high efficiency particulate air (HEPA)-filtrated airflow condition.

Microfluidic fabrication of monodisperse polylactide microcapsules with tunable structures through rapid precipitation.

We describe a versatile and facile route to the continuous production of monodisperse polylactide (PLA) microcapsules with controllable structures. With the combination of microfluidic emulsification, solvent diffusion, and internal phase separation, uniform PLA microcapsules with a perfluorooctyl bromide (PFOB) core were successfully obtained by simply diluting monodisperse ethyl acetate (EA)-in-water emulsion with pure water. Rapid extraction of EA from the droplets into the aqueous phase enabled the solidification of the polymer droplets in a nonequilibrium state during internal phase separation between a concentrated PLA/EA phase and a PFOB phase.

Absorption of the indigestible disaccharide, β-1,4-mannobiose, from coconut by the rat portal vein.

The intestinal absorption of β-1,4-mannobiose by rats was investigated. Mannobiose was detected in the portal vein plasma by matrix-assisted laser desorption ionization/time of flight mass spectrometry after its administration to rats. The presence of mannobiose in the rat plasma was confirmed by an experiment using β-mannosidase.

Synthesis of glyceryl ferulate by immobilized ferulic acid esterase.

Glyceryl ferulate was synthesized by the condensation of ferulic acid with glycerol using Pectinase PL "Amano" from Aspergillus niger, which contained ferulic acid esterase, to improve the water-solubility of ferulic acid. The optimum reaction medium was glycerol/0.1 M acetate buffer, pH 4.

Continuous synthesis of glyceryl ferulate using immobilized Candida antarctica lipase.

Glyceryl ferulate was synthesized through condensation of ferulic acid and glycerol at 50 degrees C in glycerols with different water contents using an immobilized lipase from Candida antarctica in a batch reactor, and condensation in the glycerol with a 7.5% (w/w) water content was shown to be the favorite. The solubility of ferulic acid was higher at higher temperature in glycerol with a lower water content.

Production and characterization of functional substances from a by-product of rice bran oil and protein production by a compressed hot water treatment.

A by-product of rice bran oil and protein production was treated with water and compressed hot water at 20 degrees C to 260 degrees C for 5 min, and at 200 degrees C and 260 degrees C for 5 to 120 min. Each extract was evaluated for its yield, radical scavenging activity, carbohydrate, protein, total phenolic and furfural contents, molecular-mass distribution and antioxidative activity. The maximum yield was obtained at 200 degrees C.

Properties of extracts from defatted rice bran by its subcritical water treatment.

Defatted rice bran was extracted with water and subcritical water at 50-250 degrees C for 5 min. The highest extract yield was achieved at 200 degrees C, at which the maximum amounts of protein and carbohydrate were also obtained. The total phenolic and furfural contents, radical scavenging activity, and antioxidative activity for the autoxidation of linoleic acid increased with increasing treatment temperature.

Hydrolysis kinetics of trisaccharides consisting of glucose, galactose, and fructose residues in subcritical water.

The hydrolysis kinetics of trisaccharides consisting of glucose, galactose, and fructose residues with different glycosidic bonds, 1-kestose, d-melezitose, d-raffinose, and lactosucrose, in subcritical water were conducted over the temperature range of 150-230 degrees C and at a constant pressure of 10 MPa. The hydrolysis of trisaccharides in subcritical water proceeded consecutively, i.e.

Continuous synthesis of alkyl ferulate by immobilized Candida antarctica lipase at high temperature.

1-Pentyl, 1-hexyl and 1-heptyl ferulates were continuously synthesized at 60-90 degrees C using a reactor system in which a column packed with ferulic acid powders and another column packed with immobilized Candida antarctica lipase particles were connected in series. Conversions greater than 0.9 were achieved for the synthesis of the 1-hexyl and 1-heptyl ferulates at 90 degrees C.

Thermal inactivation of immobilized lipase in 1-alcohols.

The thermal inactivation of immobilized lipase from Candida antarctica in 1-alcohols with four to eight carbons at various temperatures could be well expressed using a model in which heterogeneity in the susceptibility of the enzyme to the inactivation was assumed. It was found that the enthalpy-entropy compensation held for inactivation in 1-alcohols.

Kinetics of maltooligosaccharide hydrolysis in subcritical water.

The kinetics of the hydrolysis of maltooligosaccharides with a degree of polymerization (DP) of 3-6 in subcritical water was studied using a tubular reactor at temperatures between 200 and 260 degrees C and at a constant pressure of 10 MPa. The maltooligosaccharide disappearance and product formation at residence times shorter than 50 s could be expressed by first-order kinetics. The rate constants for the hydrolysis of each maltooligosaccharide were evaluated.

Synthesis of linoleoyl disaccharides through lipase-catalyzed condensation and their surface activities.

Monolinoleoyl trehalose, maltose and cellobiose were synthesized by Candida antarctica lipase-catalyzed condensation in an organic solvent with a low water content. The use of a mixture of pyridine and tert-butanol as the reaction medium resulted in a high product concentration on the order of mmol/l for the synthesis of linoleoyl trehalose and maltose. The highest product concentration was achieved with the 0.

Condensation reaction between angiotensin II and dicarboxylic acid in water at high temperature without any catalytic agent additive.

The condensation reaction of angiotensin II and tartaric acid in water at 100-140 degrees C proceeded without any added catalytic agent. One of the products, N-CO-tartarylangiotensin II, was confirmed by LC-MS, positive-ion MALDI-MS, and the fluorescamine method as a condensation product. The initial concentration of the substrates, temperatures, and initial pH affected the yield of the product.

Preparation of finely dispersed O/W emulsion from fatty acid solubilized in subcritical water.

A novel method for preparing a finely dispersed oil-in-water emulsion is proposed. Octanoic acid dissolved in water at a high temperature of 220 or 230 degrees C at 15 MPa was combined with an aqueous solution of a surfactant and then the mixture was cooled. When a nonionic surfactant, decaglycerol monolaurate (ML-750) or polyoxyethylene sorbitan monolaurate (Tween 20), was used, fine emulsions with a median oil droplet diameter of 100 nm or less were successfully prepared at ML-750 and Tween 20 concentrations of 0.

Decomposition kinetics of maltose in subcritical water.

The decomposition process of maltose in subcritical water was studied using a tubular reactor in the temperature range of 180 to 260 degrees C and at 10 MPa. The formation of glucose and 5-hydroxymethyl-2-furaldehyde during the maltose decomposition was also observed. The decomposition rate of maltose was faster at higher temperatures.

Relationships between structure and high-throughput screening permeability of peptide derivatives and related compounds with artificial membranes: application to prediction of Caco-2 cell permeability.

To evaluate absorption of compounds across the membrane via a transcellular route, the permeability of peptide derivatives and related compounds was measured by the parallel artificial membrane permeation assay (PAMPA). The permeability coefficients by PAMPA were analyzed quantitatively using classical QSAR and Volsurf approaches with the physicochemical parameters. The results from both approaches showed that hydrogen bonding ability of molecules in addition to hydrophobicity at a particular pH were significant in determining variations in PAMPA permeability coefficients.

Relationship between structure and permeability of dipeptide derivatives containing tryptophan and related compounds across human intestinal epithelial (Caco-2) cells.

The permeability of dipeptide derivatives containing tryptophans and indole derivatives through Caco-2 cells was used as an in vitro intestinal absorption model in order to clarify structural factors which influence their intestinal epithelial permeation and metabolism. Most peptide derivatives were hydrolysed not only by the cytosolic enzymes in Caco-2 cells during permeation but also by enzymes released to the apical solution before cell permeation. The N-terminal blocked dipeptides were more resistant to hydrolases expressed in the Caco-2 cells and indole derivatives were not entirely degraded.

Hydrolysis of the oil phase of a W/O/W emulsion by pancreatic lipase.

W/O/W emulsions are expected to protect bioactive substances from degradation by pancreatic enzymes. We investigated the enzymatic hydrolysis of the oil phase and release of a marker substance from the inner-aqueous phase to the outer-aqueous phase using an artificial digestive fluid. Octanoic acid triacylglycerol (C8TG) was used as the oil phase.

Anti-oxidant activity of acyl ascorbates in intestinal epithelial cells.

The anti-oxidant activity of acyl ascorbates, with acyl chain lengths of 10 to 18, was measured in an intestinal epithelial cell line. All the acyl ascorbates exhibited the activity for the oxidization induced by three different types of oxidants, at levels higher than ascorbic acid. Myristoyl ascorbate was the most effective and showed activity at 3 x 10(-12) to 3 x 10(-6) M.