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Capsaicin was extracted from capsicum oleoresin using an aqueous two-phase system (ATPS) composed of an ethylene oxide-propylene oxide (EOPO) copolymer, salt and ethanol. Capsaicin was concentrated in the top polymer-rich phase. To determine the optimal conditions, the partitioning of capsaicin in the ATPS was investigated, considering a single-factor experiment including the salt concentration, polymer concentration, buffer pH, ethanol concentration, sample loading and extraction duration. Response surface methodology was applied to investigate the effects of the polymer concentration, buffer pH and sample loading on capsaicin partitioning. A capsaicin yield of 95.5% was obtained using the optimal extraction system, which consisted of 16.3% UCON 50-HB-5100/10% K 2 HPO 4 /1% ethanol, a buffer pH of 4.35 and 0.24 g of capsicum oleoresin. Capsaicin was purified from the capsaicinoid extract using a two-step macroporous adsorption resin (MAR) method. After purification using non-polar MAR ADS-17, the recovery and purity of capsaicin were 83.7% and 50.3%, respectively. After purification using weakly polar MAR AB-8, the recovery and purity of capsaicin were 88.0% and 85.1%, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] ATPS was first used as a solvent to extract alliin from garlic powder. [•] Compared with traditional extraction method, aqueous two-phase extraction (ATPE) not only improved the alliin yield but also concentrated extract solution of alliin to a large extent. [•] Chromatography was used following by ATPE to purify alliin, the combination of them provided a rapid and effective method for alliin extraction and purification. [•] In this paper, cation-exchange resins 001Ã?7 was converted to NH4 + form. [ABSTRACT FROM AUTHOR]

Abstract: In this research, the effect of cross-linked acetylated starch on the set yoghurt system was studied by investigating the flowability, viscoelasticity, zeta potential, conductivity and microstructure of the set yogurt system. The results indicated that the stability, elastic modulus (G′) and viscous modulus (G″) of the set yogurt system increased as the concentrations of cross-linked acetylated starch increased. The set yogurt system, which added the cross-linked acetylated starch, exhibited shear-thinning behavior and belonged to yield pseudoplastic fluid. The SEM micrographs demonstrated that the microstructures of set yoghurt were mainly composed by the network of casein. By adding cross-linked acetylated starch, the network of casein was strengthened, and both conductivity of the yoghurt system and particle size of casein micelles due to absorption of modified starch revealed the aggrandizement trend. It can be deduced that the starch adsorbs onto the surface of the casein micelle and this phenomenon prevents flocculation of the casein micelles owing to electrostatic adhesion, steric stabilization and osmotic effect. [Copyright &y& Elsevier]

The extraction and back-extraction of bovine serum albumin (BSA) have been studied by liquid-liquid extraction with poly(ethylene glycol) (PEG)/potassium citrate aqueous two-phase system (ATPS). In this work, the ATPS was examined with regard to the effects of PEG molecular weight (PEG 1000, 2000, 4000 and 6000), PEG and potassium citrate concentration, BSA concentration (CBSA) and pH on BSA partition. The pH was found to have significant effects on BSA partition with low molecular weight PEG 1000. The yield of the BSA, 99%, was obtained in the top phase under the following conditions: 19% (w/w) PEG 1000,20% (w/w) potassium citrate and 0.75 mg/g CBSA at pH 7.0 and 30 °C. BSA can be re-extracted to a new citrate phase by decreasing the pH of the system with a 92% yield. The back-extraction not only separates the BSA from the polymer, but also allows the polymer to be recycled. The global yield (Ye +Ybe) is up to 91%. [ABSTRACT FROM AUTHOR]

The micro-structural changes of jams containing different amounts of cross-linked acetylated starch (CAS) have been studied using rheological measurements, sensory evaluation, scanning electron microscopy (SEM), and laser particle analysis. The results indicated that all samples exhibited pseudoplastic flow with yield stress. Subsequent dynamic oscillatory rheological study also showed that jam structure was more compact in the presence of 20% CAS. SEM analysis demonstrated that there was a fine, homogeneous network in the microstructure of apple jams. Furthermore, it was found that the particle size was smaller after adding CAS. Therefore, we conclude that CAS could be an appropriate gelling agent for apple jams, and the most suitable CAS content for industrial manufacturing was 20%. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC), the most common form of primary liver cancer, is the third leading cause of cancer-related death in human. Alcohol is a known risk factor for HCC. However it is still unclear whether and how alcohol enhances the progression and metastasis of existing HCC. Methods and results: We first retrospectively investigated 52 HCC patients (24 alcohol-drinkers and 28 non-drinkers), and found a positive correlation between alcohol consumption and advanced Tumor-Node-Metastasis (TNM) stages, higher vessel invasion and poorer prognosis. In vitro and in vivo experiments further indicated that alcohol promoted the progression and migration/invasion of HCC. Specifically, in a 3-D tumor/endothelial co-culture system, we found that alcohol enhanced the migration/invasion of HepG2 cells and increased tumor angiogenesis. Consistently, higher expression of VEGF, MCP-1 and NF-κB was observed in HCC tissues of alcohol-drinkers. Alcohol induced the accumulation of intracellular reactive oxygen species (ROS) and the activation of NF-κB signaling in HepG2 cells. Conversely, blockage of alcohol-mediated ROS accumulation and NF-κB signaling inhibited alcohol-induced expression of VEGF and MCP-1, the tumor growth, angiogenesis and metastasis. Conclusion: This study suggested that chronic moderate alcohol consumption may promote the progression and metastasis of HCC; the oncogenic effect may be at least partially mediated by the ROS accumulation and NF-ĸB-dependent VEGF and MCP-1 up-regulation. [ABSTRACT FROM AUTHOR]

The water-holding capacity properties of native and acetate cassava starch were evaluated by freeze-thaw stability and XRD. The results indicated that acetate starch was suitable to be used in sausage for its more stable and lower retrogradation properties compared to native starch. The water-holding capacity (WHC) of pork sausages with acetate starch was analyzed by NMR T2 relaxometry, magnetic resonance imaging (MRI), differential scanning calorimeter (DSC) and SEM. NMR T2 relaxometry and MRI displayed the significant effect of acetate starch on the water content in sausages. Water-holding capacity of sausages first increased then decreased with increase of acetate starch. The sausage with 5% w/w acetate starch had the highest content of immobilized water. The result was consistent with the data indirectly obtained from DSC. SEM analysis demonstrated that the sausage with 5% w/w acetate starch had appropriate structure and pore size to hold water. Therefore, we concluded that the sausage with 5% w/w acetate starch had the best WHC property in pork sausages. [ABSTRACT FROM AUTHOR]