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This study aims to analyze the effect of physicochemical properties of alginate-high methoxyl pectin (HMP) complexes on their performance as drug delivery systems. Rheology, textural properties and swelling behavior of alginate-HMP complexes were determined. HMP alone showed weak gelling ability. As ratio of alginate increased, gel capability, hardness and adhesiveness of gels increased, but swelling rate decreased. Bovine serum albumin (BSA) was used as a model drug and entrapped in the alginate-HMP beads. Morphology of beads was correlated with adhesiveness. Drug loading content and encapsulation efficiency were related to electrostatic interactions between BSA and alginate-HMP complexes. Drug release profiles were correlated with both texture and swelling properties of alginate-HMP complexes and morphology of beads in simulated gastric fluids, while release in simulated intestinal fluids was affected by drug loading content. This study gives enlightenment that pre-selection of encapsulation materials may be achieved prior to encapsulation based on physicochemical properties of materials. [ABSTRACT FROM PUBLISHER]

Aspergillus oryzae A-F02, a glyphosate-degrading fungus, was isolated from an aeration tank in a pesticide factory. The pathway and rate-limiting step of glyphosate (GP) degradation were investigated through metabolite analysis. GP, aminomethylphosphonic acid (AMPA), and methylamine were detected in the fermentation liquid of A. oryzae A-F02, whereas sarcosine and glycine were not. The pathway of GP degradation in A. oryzae A-F02 was revealed: GP was first degraded into AMPA, which was then degraded into methylamine. Finally, methylamine was further degraded into other products. Investigating the effects of the exogenous addition of substrates and metabolites showed that the degradation of GP to AMPA is the rate-limiting step of GP degradation by A. oryzae A-F02. In addition, the accumulation of AMPA and methylamine did not cause feedback inhibition in GP degradation. Results showed that degrading GP to AMPA was a crucial step in the degradation of GP, which determines the degradation rate of GP by A. oryzae A-F02. [ABSTRACT FROM AUTHOR]

Probiotic bacteria are being increasingly added to food for developing products with health-promoting properties. However, the efficacy of probiotics in commercial products is often questioned due to the loss of their viability during shelf storage and in human gastrointestinal tracts. Encapsulation of probiotics has been expected to provide protection to probiotics, but not many commercial products contain encapsulated and viable probiotic cells owing to various reasons. To promote the development and application of encapsulation technologies, this paper has critically reviewed previous publications with a focus on the areas where studies have fallen short, including insufficient consideration of structural effects of encapsulating material, general defects in encapsulating methods and issues in evaluation methodologies and risk assessments for application. Corresponding key issues that require further studies are highlighted. Some emerging trends in the field, such as current treads in encapsulating material and recently advanced encapsulation techniques, have also been discussed. [ABSTRACT FROM AUTHOR]

This study aimed to obtain strains with high glyphosate-degrading ability and improve the ability of glyphosate degradation enzyme by the optimization of fermentation conditions. Spore fromAspergillus oryzaeA-F02 was subjected to ultraviolet mutagenesis. Single-factor experiment and response surface methodology were used to optimize glyphosate degradation enzyme production from mutant strain by liquid-state fermentation. Four mutant strains were obtained and named as FUJX 001, FUJX 002, FUJX 003, and FUJX 004, in which FUJX 001 gave the highest total enzyme activity. Starch concentration at 0.56%, GP concentration at 1,370 mg/l, initial pH at 6.8, and temperature at 30°C were the optimum conditions for the improved glyphosate degradation endoenzyme production ofA. oryzaeFUJX 001. Under these conditions, the experimental endoenzyme activity was 784.15 U/100 ml fermentation liquor. The result (784.15 U/100 ml fermentation liquor) was approximately 14-fold higher than that of the original strain. The result highlights the potential of glyphosate degradation enzyme to degrade glyphosate. [ABSTRACT FROM AUTHOR]

A lignan-rich diet is associated with a lower risk of human breast cancer. Enterolactone, an active polyphenol metabolites of lignan, was reported to have an antitumor effect. We investigated the mechanism for the effect of enterolactone against human breast cancer. Cellular changes, and associated genes induced by enterolactone, were investigated in MDA-MB-231 cells. Enterolactone showed an antiproliferative effect, and its IC50was 261.9 ± 10.5 μM for a treatment period of 48 hr. The mRNA levels of the genes related to cell proliferation, Ki67, PCNA, and FoxM1, were reduced. Enterolactone induced accumulation of cells in the S phase, and a lower expression of Cyclin E1, Cyclin A2, Cyclin B1, and Cyclin B2 genes. There were almost no changes in the transcription levels of the genes that participate in G0/G1 phase regulation, CDK4, CDK6, and Cyclin D1. Furthermore, enterolactone interfered with the cytoskeleton by downregulating phosphorylation of the FAK/paxillin pathway, inhibiting migration and invasion of cells. The results suggest that enterolactone exerts an antitumor effect by regulating the expression of genes associated with cell proliferation and the cell cycle and by blocking the FAK/paxillin signaling pathway. These findings provide new insights into the molecular mechanisms behind the antitumor effect of enterolactone. [ABSTRACT FROM AUTHOR]

In recent years, the interest in studying modification of pectin has increased. A number of hydroxyl and carboxyl groups distributed along the backbone as well as a certain amount of neutral sugars presented as side chains make pectin capable of preparing a broad spectrum of derivatives. By forming pectin derivatives, their properties may be modified and some other new functional properties may be created. This article attempts to review the information about various methods used for pectin modification, including substitution (alkylation, amidation, quaternization, thiolation, sulfation, oxidation, etc.), chain elongation (cross-linking and grafting) and depolymerization (chemical, physical, and enzymatic degradation). Characteristics and applications of some pectin derivatives are also presented. In addition, the safety and regulatory status of pectin and its derivatives were reviewed. [ABSTRACT FROM AUTHOR]

Phosphorus-containing hyperbranched aromatic-aliphatic polyamides are prepared via direct polymerization of triacid (B3) with different diamines (A2), which for improving the processability of aromatic polyamides while keeping exellent thermal and mechanical property. The triacid (B3), tris(2-carboxyethyl)phosphine oxide (TCEPO), is synthesized from tetrakis(hydroxymethyl)phosphonium sulfate and its structure is verified by Fourier transform infrared,1H,13C and31P NMR spectroscopy. Then, the polycondensation reaction of TCEPO withp-phenylene diamine, 4,4′-oxyphenylene diamine and 4,4′-methylenedianiline result in three phosphorus-containing hyperbranched aromatic-aliphatic polyamides, and the degree of branching is found between 0.66 and 0.71. Gel permeation chromatography measurement reveal that all hyperbranched aromatic-aliphatic polyamides have moderate number-averaged molecular weights and narrow molecular weight distribution. The Dynamic mechanical thermal analysis results show all polymers have two glass transition temperatures (Tg) in the temperature range 85.3–128.0 °C and have high storage modulus about 1.52–3.19 GPa at 50 °C. The TGA results reveal the initial degradation temperatures (T5) and the temperatures for 10% gravimetric loss (T10) for the hyperbranched aromatic-aliphatic polyamides are in the range of 214–250 and 256–333 °C, and the maximum decomposition temperatures (Tm) are about 500 °C, and also the char yields of polymers at 850 °C are about 39.4–48.4%, which indicate good thermal stability. [ABSTRACT FROM AUTHOR]

A new phosphorus-containing dicarbamates, di(N-carbomethoxylaminomethyl)benzyl phosphine oxide was first synthesized from tetrakis(hydroxymethyl)phosphonium sulfate (THPS) via five step reactions (Scheme 1), and its structure was proved by FTIR, (1H,13C, and31P) NMR, and MS. A series of thermally stable phosphorus-containing polyureas were synthesized via trans-ureation polycondensation of the new monomer with aliphatic diamines, including poly(propylene glycol) bis(2-aminopropyl ether), respectively. All of the above polyureas were fully characterized by inherent viscosity, GPC, solubility tests, and thermogravimetric analysis. The thermal gravimetric analysis results showed that the initial breakdown temperature of all phosphorus-containing polyureas was observed at above 265 °C while complete weight loss occurred in the region of 406–465 °C, which shows all polyureas have good thermal stability. GPC results showed that the maximum number-average molecular weight of the synthesized polyureas reached 59,100 g mol−1. The solubility tests results demonstrated that incorporating the ether moieties into the polymer main chain can enhance the solubility of polyureas in organic solvents. [ABSTRACT FROM PUBLISHER]

A new polymer containing α-aminophosphonate unit (PAP) was synthesized through a simple and solvent-free Kabachnik–Fields reaction, and was characterized by NMR, FTIR, and gel permeation chromatography (GPC). This polymer was used as a novel reactive, halogen-free flame retardant. The curing behavior of bisphenol A type epoxy resin with PAP was investigated by differential scanning calorimetry (DSC), and the glass transition temperatures (Tg) of the cured sample were determined by dynamic mechanical analysis. Flammability and thermal stability of the cured epoxy resins with different contents of PAP were investigated by UL-94 test and thermogravimetric analysis (TGA). The results of UL-94 test and TGA show that PAP could improve the flame retardancy and thermal stability of cured epoxy resins. As the content of PAP was more than 20% in weight, the flame retardancy of epoxy resin can pass V-0 rating. [ABSTRACT FROM AUTHOR]

Micronized by a dry grinding method (D-ODF) or a wet granulating method (W-ODF), okara dietary fiber (ODF), was fed to BALB/c mice for 28 d. The water holding capacity of D-ODF and W-ODF was significantly enhanced after micronization. W-ODF had a larger swell capacity and a higher content of soluble dietary fiber than crude ODF and D-ODF. After feeding for 28 d, the populations of Escherichia coli and Lactobacilli in the cecum were significantly lower and higher in the W-ODF group than other groups, respectively, while the population of Bifidobacterium increased in all groups. The effect of each diet on the population of E. coli. Lactobacilli and Bifidobacterium was all maintained for a short period of time except that the effectiveness of W-ODF diet on the Bifidobacterium population lasted slightly longer than other diets. At the end of the feeding period, serum total cholesterol (TC) and triglyceride in D-ODF and W-ODF diets were significantly lower and HDL-C/TC ratio was significantly higher than those in crude ODF. [ABSTRACT FROM AUTHOR]

The synthesis and mesomorphic properties of a class of cyclotriphosphazenes containing cyanostilbene groups with different terminal substituents (-H, -CH3, -OCH3, -CN) are described. All the resulting compounds are characterized by 1H, 13C, and 31P NMR, matrix-assisted laser desorption/ionization time of flight, and elemental analysis. The thermal behaviors of cyclotriphosphazene derivatives are studied by the means of differential scanning calorimetry and polarizing optical microscopy. Nematic phases are observed in cyclotriphosphazenes with terminal substituents (-CH3, -OCH3, -CN). [ABSTRACT FROM AUTHOR]

[image omitted] Tetrazoles were introduced into cyclotriphosphazenes to obtain hexakis-(4-tetrazolylphenyloxy)cyclotriphosphazene (2) in good yield (88.9%) by reacting hexakis-(4-cyanophenyloxy)cyclotriphosphazene (1) with sodium azide in N,N-dimethylformamide (DMF) in the presence of NH4Cl as a catalyst. Its alkylonitrile derivative, hexakis-(4-cyanoethyltetrazolylphenyloxy)cyclotriphosphazene (3), was prepared by the reaction of 2 with acrylonitrile in acetonitrile, using triethylamine as a catalyst. [ABSTRACT FROM AUTHOR]