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关键词： caffeic acid phenethyl ester   casein   encapsulation   bioaccessibility   anticancer activity  

摘要： Caffeic acid phenethyl ester (CAPE) has various biological activities but low water solubility and poor bioavailability. In this study, CAPE was encapsulated in skim milk powder (SMP) by spray drying warm aqueous ethanol solutions with different mass ratios of SMP and CAPE. The loading capacity and encapsulation efficiency were up to 10.1 and 41.7%, respectively. Differential scanning calorimetry and X-ray diffraction results confirmed the loss of crystallinity of CAPE after encapsulation. Fourier-transform infrared and fluorescence spectroscopy results indicated the hydrophobic binding between CAPE and caseins. Scanning electron microscopy and static light scattering results showed spherical capsules with an average diameter of around 26 mu m. The CAPE loaded in SMP microcapsules showed significantly improved in vitro bioaccessibility and antiproliferation activity against human colon cancer cells compared to free CAPE. The simple, scalable, and low-cost approach in the present study may be significant for industrial encapsulation of CAPE and other lipophilic bioactive compounds.

关键词： Polysaccharides from Rosa roxburghii Tratt. leaves   Extraction and purification   Biological activity  

摘要： The optimum extraction conditions of polysaccharides from roxburgh rose (Rosa roxburghii Tratt.) leaves (RLP) were obtained by response surface methodology (RSM), which were a liquid to solid ratio of 21.16 mL/g, an extraction temperature of 81.32 degrees C, and an extraction time of 90.49 min. An RLP yield of 11.04% was obtained under these conditions. DEAE-52 cellulose and Sepharose CL-6B columns were used to purify the RLP, and the purified polysaccharide components RLP-1.2 and RLP-2.1 were obtained. Both RLP-1.2 and RLP-2.1 were composed of galacturonic acid (GalA), glucose (Glc), galactose (Gal), and arabinose (Ara). However, the molar ratios of GalA, Glc, Gal, and Ara in RLP-1.2 and RLP-2.1 were different. At a concentration of 10 mg/mL, the a-amylase inhibitory activities of RLP-1.2 and RLP-2.1 reached 80.74% and 89.85% that of acarbose, respectively, and the aglucosidase inhibitory activity of RLP-1.2 reached 87.91% that of acarbose. In addition, both RLP-1.2 and RLP2.1 showed good antioxidant activity. These results suggested that RLP-1.2 and RLP-2.1 possess potential as natural hypoglycemic agents or natural antioxidants. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Konjac glucomannan   Alginate   Sugarcane vinasse   Film   Mulching  

摘要： Biodegradable films are a promising strategy to reduce the environmental impact caused by conventional plastics commonly used in agriculture. This study focused on the production and characterization of Konjac glucomannan (KGM) and alginate (ALG) based films enriched with sugarcane vinasse (VIN), a nutrient-rich wastewater generated in large volumes by the sugar-ethanol producing industries. ALG, KGM and ALG/KGM blended (50:50) films were produced by casting and treated with calciumions (Ca2+) (ALGfilms) and a combination of Ca2+, alkali, and ethanol (KGM and ALG/KGM films). Vinasse addition tended to reduce transparency and water resistance of the films and had less effect on their mechanical properties. Crosslinking of ALG films resulted in enhanced mechanical properties and reduced moisture content, water solubility, swelling, water vapor permeability, and flexibility. KGM films were less impacted by crosslinking/deacetylation but showed improved water resistance while maintain a high degree of swelling (290% and 185% for KGM and KGM/VIN films respectively). Blended films exhibited characteristic properties of the two biopolymers and adequate compatibility indicated by Fourier transform infrared spectroscopy (FTIR) and morphologies. Vinasse-added ALG/KGM films represent a novel nutrient-enriched, bio-based material for agricultural applications and could help to face the environmental challenges imposed by vinasse disposal. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Camel whey proteins   X-ray Photoelectron spectroscopy   LC-MS   Glass transition temperature  

摘要： This study investigated the effect of pH on the denaturation extent, the surface chemical composition, the water sorption isotherm and the glass transition temperature of camel and bovine whey protein's powders. The LC-MS analysis indicated that the beta-Lactoglobulin was the most denatured protein in bovine whey powders regardless the pH value, while this protein was totally absent in camel whey. The alpha-Lactalbumin was relatively heat stable after drying and predominated the powder surface (X-ray photoelectron spectroscopy results) in both camel and bovine whey powders regardless the pH (neutral (6.7) or acidic (4.3 and 4.6)). Analysis of the water sorption isotherms indicated that decreasing the pH induced the increase of the water activity of lactose crystallization for camel and bovine whey powders. Finally, decreasing the pH led to the decrease of the glass transition temperature of camel and bovine whey powder (at 0.13, 0.23, and 0.33 of water activity).

关键词： Yam   Polysaccharide   Sulfation   Immunomodulatory   Immunosuppressed mice  

摘要： A sulfated Chinese yam polysaccharide (S-CYP) was obtained from non-starch Chinese yam polysaccharide (CYP) by chlorosulfonic acid-pyridine (CSA-Pyr) method. The physicochemical characteristics and immunological activity of S-CYP were evaluated in this study. Results showed that sulfated modification changed the physicochemical properties of Chinese yam polysaccharide. Body weights and thymus index of the mice in polysaccharides group were increased compared with the cyclophosphamide (Cy)-induced immunosuppressed mice in model group, and could restore the splenomegaly that caused by Cy. It also showed that S-CYP could enhance the immunomodulatory activity on splenic lymphocytes since it could increase the proliferation of splenic lymphocytes and effectively cooperate with ConA to induce splenic lymphocytes differentiation into T lymphocytes. Meanwhile, the number of CD3(+)CD4(+) and CD3(+)CD8(+) T lymphocytes was elevated, the CD4+/CD8+ ratio was restored in polysaccharides group. The levels of splenic lymphocytes cytokines (interleukin (IL)-1 beta, tumor necrosis (TNF)-alpha), and the levels of immunoglobulin (IgG and IgM) secretion in serum were also increased by S-CYP significantly. These findings demonstrate that CYP and S-CYP can serve as a promising immunomodulator with potential application in functional food and nutraceutical industry. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Ionic liquid   Eutectic   DSSC   Electrolyte   COSMO-RS  

摘要： Ionic liquids (ILs) have been introduced as the electrolyte in dye-sensitized solar cells (DSSC) to replace organic solvents due to their non-flammability, chemical, and thermal stability, as well as less prone to evaporation and leakage. A series of eutectic Its mixtures composed of 1-ethyl-3-methylimidazolium iodide, [C(2)C(1)im]I, 1-ethylpyridinium iodide [C(2)py]I, 1-propylpyridinium iodide, [C(3)py]I and 1-butylpyridinium iodide, [C(4)py]I was developed. The structures and purity of the compounds were validated by nuclear magnetic resonance and Karl Fischer Titration. Their physicochemical properties, such as viscosities and ionic conductivities were evaluated for their potential use as electrolytes in DSSCs. The melting temperature of pure ionic liquids and the mixtures were determined using differential scanning calorimetry in the temperature range of 123.15 K to 393.15 K. It is found that eutectic mixtures were formed at the molar ratios of {0.75[C(2)py]I:0.25[C(2)C(1)im], {0.25[C(2)py]I:0.75[C(2)C(1)im]I}, {0.50[C2Py]I: 0.50[C(2)C(1)im]I}, {0.25[C(2)C(1)im]I:0.75[C(4)py]I}, {0.75[C(2)C(1)im]I:0.25[C(4)py]I}. and {0.50[C(2)C(1)im]I:0.50[C(4)py]I} with the latter forming a highly stable liquid with no apparent melting peak in the studied temperature range. To understand the formation of eutectic composition, a correlation between molecular structures and the interaction energies of the cations and anions of ILs was performed using the Conductor-like Screening Model for Real Solvents (COSMO-RS). Dynamic viscosities of the binary mixtures were evaluated in the temperature range of 283.15 K to 353.15 K with 10K increment The highest ionic conductivity was exhibited by the eutectic ILs electrolyte {0.50[C(2)C(1)im]I:0.50(C(4)py]I:I-2(50 wt%)} at 9.67 ***(-1) showing its potential for electrolyte application in DSSC. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Schinus   Polysaccharides   Biological activities  

摘要： The aim of the current study was to compare crude polysaccharides extracted from Schinus terebinthifolius Raddi (PSTF) and S. molle L. (PSMF) fruits based on their structures, physicochemical characteristics, monosaccharide composition, as well as in vitro and in vivo assays. The extraction yield of PSTF (4.26%) was higher than that of PSMF (3.56%). Remarkable variability was detected in the content of carbohydrates (80.64 +/- 0.98%), protein (1.80 +/- 0.28%), fat (0.04 +/- 0.005%) and ash (6.32 +/- 0.26%). FT-IR assay and H-1 and C-13 NMR spectroscopy revealed that fruits extract showed similar structural characteristics. Thin layer chromatography together with HPLC-RID analysis showed that the monosaccharide composition varied significantly between species. Both contained arabinose (40.55-42.03%) galacturonic acid (31.21-41.15%), and fucose (10.90-17.63%), but PSTF had glucose (9.13%) whereas PSMF had galactose (7.40%). Functional analyses demonstrated that samples exhibited favorable water- and oil-retention capacity, emulsifying properties, and foaming qualities. PSTF exhibited the highest antioxidant effects. Both of them showed a remarkable in vitro antidiabetic effect. PSMF highly mitigated H2O2-induced hemolysis and exhibited similar to 80% antihemolytic activity. The extracted polysaccharides showed potent inhibitory activity against AAPH-induced plasmid DNA damage. PSTF and PSMF revealed interesting in vivo antinociceptive and anti-inflammatory capacities. (C) 2020 Published by Elsevier B.V.

关键词： Copper   Alkaline corrosion   Charge transfer complexes   Single crystal   Corrosion inhibitor   DFT   B3LYP   Quantum chemical calculation  

摘要： Two charge transfer complexes, namely [(BDAH)(+)(PA(-))] CT1 [(BTAH)(2+) (PA(-))(2)] and CT2 (BDAH = 1,2-benzenediamine, BTAH = 1,2,4,5-benzenetetramine, and PA(-) = 2,4,6-trinitrophenolate), were synthesized and fully characterized using various spectroscopic techniques. CT1 and CT2 were tested as inhibitors to effectively control the uniform and anodic corrosion processes of copper in an alkaline electrolyte (1.0 M KOH) using various electrochemical techniques. As a reference point, results were compared with the potassium salt of the pi-acceptor potassium 2,4,6-trinitrophenolate (designated here as PA(-)K(+)). The highest inhibition efficiency (97%) was recorded for inhibitor CT2 at a concentration of 1.0 mM. The inhibition mechanism was discussed based on scanning electron microscopy and X-ray photoelectron spectroscopy results of the corroded and inhibited Cu surfaces. A theoretical study, based on quantum-chemical calculations of the synthesized compounds. performed by the DFF/B3LYP method with a 6-311++G(2d,2p) basis set by using Gaussian 09, Revision A.02 program, was also included to support experimental findings. The various quantum chemical parameters such as E-HOMO, E-LUMO, chemical hardness, and chemical softness of the investigated molecules were calculated, and their correlation with the inhibition efficiency of the synthesized compounds was discussed. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Mesalazine   Biopolymer   Hemicellulose   Drug delivery systems   DDsolver  

摘要： Xylan extracted from corn cobs was used to produce mesalamine-loaded xylan microparticles (XMP5-ASA) by cross-linking polymerization using a non-hazardous cross-linking agent. The microparticles were characterized by thermal analysis (DSC/TG), X-ray diffraction (XRD), Infrared spectroscopy (FTIR-ATR) and scanning electron microscopy (SEM). A comparative study of the in vitro drug release from XMP5-ASA and from gastro-resistant capsules filled with XMP5-ASA (XMPCAP5-ASA) or 5-ASA was also performed. NMR, FTIR-ATR, XRD and DSC/TG studies indicated molecularly dispersed drug in the microparticles with increment on drug stability. The release studies showed that XMPCAP5-ASA allowed more efficient drug retention in the simulated gastric fluid and a prolonged drug release lasting up to 24 h. XMPCAP5-ASA retained approximately 48 % of its drug content after 6 h on the drug release assay. Thus, the encapsulation of 5-ASA into xylan microparticles together with gastro-resistant capsules allowed a better release control of the drug during different simulated gastrointestinal medium.

关键词： Okra stems   Pectins   Anti-fatigue activity  

摘要： Okra, Abelmoschus esculentus (L.) Moench, an annual herbaceous plant, is widely distributed in tropical and subtropical regions. Water-soluble pectic hydrocolloids from okra stems (HOS) were extracted and purified using polydivinylbenzene HP-20 resins. The sugar composition of the purified HOS with an weight-average molecular weight of 178.4 +/- 2.1 kDa and a polydispersity index of 1.02 +/- 0.02 contained galacturonic acid (34%), galactose (31%), rhamnose (21%), arabinose (4.2%), glucuronic acid (2.5%), xylose (1.2%), and other monosaccharides (6.1%) by weight. Its favorable rheological behaviors were evident on relatively higher concentrations (20, 25, and 30 mg/mL) and moderately lower pH levels (3 and 5) of HOS. The anti-fatigue experiments in vivo demonstrated that a high dose of HOS (450mg/kg feed) prolonged the exhaustive swimming time of mice, significantly induced an increase in blood glucose and glycogen, and decreased lactic acid and serum urea nitrogen levels. HOS digestion in vivo was fairly conducive to the improvement of energy storage capacity and renal function for physically induced fatigue, compared with the conventional herbal supplement Panax quinquefolium. Accordingly, HOS exhibits potential for reutilization of okra stem waste. (C) 2020 Elsevier B.V. All rights reserved.