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排序方式: 共有1581条查询结果,搜索用时 156 毫秒
91.
Min‐Jung Bae Takeshi Ishii Kanako Minoda Yukiko Kawada Tatsuya Ichikawa Taiki Mori Miya Kamihira Tsutomu Nakayama 《Molecular nutrition & food research》2009,53(6):709-715
(–)‐Epigallocatechin gallate (EGCg) is the major component of green tea and is known to show strong biological activity, although it can be easily oxidized under physiological conditions. In this study, we indicate that EGCg is stable in human serum and that human serum albumin (HSA) stabilizes EGCg under aerobic condition. Although EGCg is usually decomposed within 1 h in aqueous solution at neutral pH, EGCg in serum and phosphate buffer (pH 7.4) containing HSA was stable over 1 h, even at neutral and slightly alkaline pH. Under these conditions, EGCg binds to HSA non‐covalently. The sulfhydryl group acts as an antioxidant for EGCg oxidation. Incubation of EGCg with HSA is accompanied by the oxidation of a free sulfhydryl group in HSA. These results suggest that the antioxidant property and the binding capacity of HSA contribute to the stabilization of EGCg in human serum. 相似文献
92.
93.
Model oil-in-water emulsions containing epicatechin (EC) and epigallocatechin gallate (EGCG) showed a synergistic increase in stability in emulsions containing added albumin. EGCG showed a stronger synergy (35%) with ovalbumin than did EC. Oxidation of the oil was monitored by determining peroxide values and hexanal contents. The effect of bovine serum albumin (BSA) on model oil-in-water emulsions containing each of the green tea catechins [epicatechin gallate (ECG), EGCG, EC and epigallocatechin (EGC)] was studied during storage at 30 °C. The green tea catechins showed moderate antioxidant activity in the emulsions with the order of activity being ECG ≈ EGCG > EC > EGC. Although BSA had very little antioxidant activity in the absence of phenolic antioxidants, the combination of BSA with each of the catechins showed strong antioxidant activity. BSA, in combination with EC, EGCG or EGC, showing the strongest antioxidant activity with good stability after 45 days storage. Model experiments with the catechins stored with BSA in aqueous solutions confirmed that protein–catechin adducts with antioxidant activity were formed between the catechins and protein. The antioxidant activity of the separated protein–catechin adducts increased strongly with storage time and was stronger for EGCG and ECG than for EC or EGC. 相似文献
94.
Hidetaka Kawakita Hiroyasu Masunaga Kanako Nomura Kazuya Uezu Isamu Akiba Satoshi Tsuneda 《Journal of Porous Materials》2007,14(4):387-391
Protein adsorption was performed by a polymer brush prepared by atom-transfer radical polymerization (ATRP) to a porous inorganic
membrane. The porous inorganic membrane, Shirasu Porous Glass made from silica, was modified with a halogen-containing compound
to bind the active species for the polymerization. Glycidyl methacrylate was polymerized from the halogen compound by ATRP
for a prescribed time, and subsequently chemically modified. The progression of the chemical modification allowed the membrane
to lower the phosphate-buffer flux of the porous membrane due to the attachment of the polymer brush. Bovine serum albumin
(BSA), as a model protein, was adsorbed at 12 mg per gram of the membrane in permeating BSA solution through the polymer-brush-attached
porous membrane. 相似文献
95.
96.
《Ceramics International》2015,41(6):7565-7572
A variety of advanced functions such as hydrophilicity and hydrophobicity are required for transparent glass plates recently. This paper reports a new procedure to produce transparent silica thin films on glass plates obtained from sodium silicate as inexpensive silica source by its dip coating and subsequent deposition of silica with (NH4)2SO4 solution. When the thin films were prepared using bovine serum albumin (BSA), the resulting transparent films became more hydrophobic than that obtained without BSA and had good adhesion with water droplet, the so-called “petal effect”. Water droplet on the silica thin film did not slide down even when the substrate turned vertically and upside down. Although no BSA was included in the silica thin film, BSA contributed to the formation of nano-sized asperity structures in the film, producing more hydrophobic (less hydrophilic) property and the petal effect. 相似文献
97.
以咖啡酸、间羟基肉桂酸为母体,分别与止血芳酸反应,设计合成两种羟基肉桂酸衍生物I、II,并用MS、IR、1H-NMR、13C-NMR进行结构表征。采用荧光光谱法、同步荧光光谱法、紫外可见光谱法结合分子对接技术研究其在体外生理条件下与HSA之间的相互作用机制。光谱实验结果表明,衍生物I和II都可以使HSA的内源荧光发生静态猝灭,相互作用力主要是氢键和范德华力,且对HSA的构象产生一定的影响。分子对接结果表明衍生物I、II与HSA中的结合位于亚结构域IIA(即site I)中,作用力主要是氢键和范德华力,同时还存在着疏水作用,且衍生物距色氨酸残基(Trp214)很近,很好地解释了衍生物有效猝灭HSA内源荧光的实验现象。分子对接与实验获得了一致性的结果,二者相互作证,提高了实验结果推断的准确度。 相似文献
98.
利用了荧光发射光谱,同步荧光光谱,紫外吸收光谱进行了检测,研究有机磷农药(草甘膦和马拉硫磷)与牛血清白蛋白的相互作用,实验结果表明了有机磷农药对牛血清白蛋白有着明显的荧光猝灭作用,且方式为静态猝灭(BSA荧光分子与猝灭剂有机磷农药之间通过弱的结合生成复合物,该复合物会使得荧光完全猝灭的现象)为主。通过实验得出有机磷与牛血清白蛋白的结合位点数(n),与结合常数(K0)。 相似文献
99.
100.
Tanaka T Tanaka M Tanaka T Ishigamori R 《International journal of molecular sciences》2010,11(9):3209-3225
Colorectal cancer (CRC) is the third most common epithelial malignancy in the world. Since CRC develops slowly from removable precancerous lesions, detection of the lesion at an early stage by regular health examinations can reduce the incidence and mortality of this malignancy. Colonoscopy significantly improves the detection rate of CRC, but the examination is expensive and inconvenient. Therefore, we need novel biomarkers that are non-invasive to enable us to detect CRC quite early. A number of validation studies have been conducted to evaluate genetic, epigenetic or protein markers for identification in the stool and/or serum. Currently, the fecal occult blood test is the most widely used method of screening for CRC. However, advances in genomics and proteomics will lead to the discovery of novel non-invasive biomarkers. 相似文献