毛细管电泳法手性拆分橙皮苷对映体

通过考察电泳缓冲液pH、环糊精种类和浓度、有机溶剂浓度及操作电压和温度对分离的影响,建立了一种简便快捷的高效毛细管电泳拆分橙皮苷对映体的方法。实验结果表明,以12mmol/L的羟丙基-β-环糊精为手性选择剂,200mmol/L的硼酸/甲醇(V:V=7:3,pH9.7)为电泳缓冲溶液,23kV的分离电压,在30℃下可使橙皮苷对映体达到基线分离,分离度为1.50。分析方法快速简单。     

Protein and Amino Acid Profiles in Natural and Artificial Shark Fins using Capillary Electrophoresis

The potential utility of capillary electrophoresis (CE) for differentiation between natural and artificial shark fins was established. Three major protein components (peaks I-III) of shark fins were well-separated and used as parameters for differentiation between natural and artificial shark fins. The height ratio of protein peak III to protein peak I was higher in natural shark fins than that in artificial products. Further, the profile of amino acids in natural dried shark fins was somewhat different from that in artificial samples. The level of tyrosine was especially high (5.11-8.11%) in natural dried shark fins, but low or not detectable (0-0.22%) in artificial samples.     

应用纳滤膜分离大豆黄浆水的研究

试验研究了操作条件对纳滤膜分离无机盐水溶液以及蔗糖水溶液的影响 ,并对大豆黄浆水超滤透过液进行了纳滤浓缩试验。结果表明 ,操作条件对NaCl、KCl、CaCl2 的截留率影响较大 ,而对MgCl2 、Na2 SO4和蔗糖水溶液基本没有影响。纳滤浓缩大豆黄浆水超滤透过液 ,适宜的操作条件为操作压强 0 5MPa ,温度 4 0℃。     

A Survey of the Peptide Profile in Prato Cheese as Measured by MALDI‐MS and Capillary Electrophoresis

In this study, we describe the characterization of the peptide profile in commercial Prato cheese by matrix‐assisted laser desorption ionization mass spectrometry (MALDI‐MS) and capillary electrophoresis (CE). Ten commercial Prato cheese brands were characterized via their physicochemical composition and subjected to fractionation according to solubility at pH 4.6. The pH 4.6 insoluble fraction was evaluated by CE, whereas MALDI‐MS was applied to the fraction soluble at pH 4.6 and in 70% ethanol. CE revealed a characteristic pattern of hydrolysis, with formation of para‐κ‐casein, hydrolysis of α_s1‐casein at the Phe₂₃ ‐ Phe₂₄ bond, and hydrolysis of β‐casein. For the MALDI‐MS data, a complex peptide profile was observed, with the identification of 44 peptides previously reported (24 peptides from α_s1‐casein, 14 from β‐casein, 3 from κ‐casein, and 3 from α_s2‐casein). It was also observed that cheeses with salt‐in‐moisture content greater than 5% showed an accumulation of a bitter‐tasting peptide (m/z 1536, α_s1‐CN f1‐13), suggesting a relationship between the higher salt concentration and the abundance of this peptide. In conclusion, the results showed that even commercial cheeses produced with different raw material and processing conditions showed very similar peptide profiles when assessed at the molecular level, and only 9 peptides were responsible for discrimination of cheeses.     

膜技术在分离纯化大豆低聚糖中的应用

本文介绍了国内外利用膜技术从大豆乳清中分离纯化大豆低聚糖的研究进展,证明利用膜技术分离纯化大豆低聚糖是非常有效的,且发展前景十分广阔。但目前存在的主要问题是膜及膜组件的污染。     

膜技术在分离纯化大豆低聚糖中的应用

本文介绍了国内外利用膜技术从大豆乳清中分离纯化大豆低聚糖的研究进展,证明利用膜技术分离纯化大豆低聚糖是非常有效的,且发展前景十分广阔.但目前存在的主要问题是膜及膜组件的污染.     

膜分离大豆乳清蛋白的研究

对膜分离大豆乳清蛋白进行了探讨,讨论了截留分子量、压力、温度、pH值对超滤的影响。结果表明:采用截留分子量10000的膜超滤,超滤压力0·2MPa,超滤温度40~50℃,超滤pH值7·5,蛋白质的截留率达90%以上,总糖透过率为80%以上。     

毛细管电泳法分析蜂花粉中黄酮类化合物(英文)

使用毛细管电泳法(CE)检测了健康食品中常见的六种黄酮类化合物:橙皮甙、海棠甙、异鼠李素、山奈酚、槲皮素、芦丁。研究了一系列的试验参数,如:pH、缓冲溶液浓度、分离电压以及UV检测器波长等,以确定出最佳条件。使用H3BO3-Na2B4O7缓冲液(pH9.2),各分析物可在8min内分出。相对标准偏差(RSD):8次进样的迁移时间为0.77%～0.93%;峰面积为3.8%～8.6%;各检测限(S/N=3)范围为0.34μg/ml～2.9μg/ml,回收率为80.4%～113.9%。方法简单、灵敏,重现性高,线性好,无须固相萃取前处理,用于蜂花粉分析结果准确。     

高效毛细管电泳同时分离多种酚类物质

建立了高效毛细管电泳同时分离测定芦丁、槲皮素、绿原酸、咖啡酸、没食子酸和原儿茶酸6种酚类物质的分析方法。考察了缓冲液种类、离子浓度和pH、分离电压、运行温度等电泳参数,确立了最佳的电泳条件:缓冲液为20 mmol/L磷酸二氢钠-20 mmol/L硼砂,pH7.5,分离电压为20 kV,运行温度为30℃,紫外检测波长214 nm。结果表明,6种物质在12 m in内得到完全分离,且各组分质量浓度与峰面积呈良好的线性关系,R2为0.998 7~0.987 4。方法精密度试验中,迁移时间的RSD为0.280%~0.425%,峰面积的RDS为5.228%~8.506%,回收率为85.11%~101.98%。该法快速、简便、准确,具有较高的灵敏度。     

Structure Analysis of Carboxymethyl Starch by Capillary Electrophoresis and Enzymic Degradation

Carboxymethyl starches (CMS) with a degree of substitution (DS) in the range of 1.2 to 1.5 were analysed by capillary electrophoresis (CE) after hydrolysis and reductive amination in a borate buffer. The monomer composition determined was compared to data calculated by the statistical models of Spurlin and Reuben. In addi­tion, the starch derivatives were exhaustively degraded by α‐amylase and amylo­glucosidase and the amount of glucose liberated was determined. Results were discussed with regard to derivatisation conditions and properties of the carboxymethyl starches.     

毛细管电泳法对乳及乳制品中乳源蛋白的测定

采用毛细管电泳方法对乳及乳制品中乳源蛋白成分进行检测.选择聚乙烯醇涂层毛细管,采用柠檬酸缓冲体系,在紫外检测214 nm、分离电压20 kV条件下对乳及乳制品中的α-乳白蛋白(α-La)、β-乳球蛋白(β3-Lg)、α-酪蛋白(α-CN)、β-酪蛋白(β-N)和k-酪蛋白(k-N)进行分离测定.五种蛋白线性良好,线性相关系数均大于0.997 8,各蛋白峰面积的相对标准偏差为1.76％～3.28％,加标回收率范围为88.1％～110.8％.应用该方法对液态奶、酸奶及奶粉中的乳源蛋白进行测定.本法准确、简便、易行,适于测定液态奶、酸奶、奶粉中蛋白质的检测.     

区带毛细管电泳法同时分离检测6种喹诺酮类抗生素

采用区带毛细管电泳法建立6种喹诺酮类抗生素同时分离检测的方法,考察了缓冲液种类、离子浓度、pH以及分离电压,温度等因素对电泳分离的影响.优化后的分离检测条件为:缓冲液为30mmol/L硼酸钠-10mmol/L磷酸二氢钠(pH8.5)、分离电压和温度分别为18kV和25℃、紫外检测波长278mm.结果表明,6种药物在10min内完全达到基线分离,且各组分浓度与峰面积呈良好的线性关系(R2>0.9929),检出限为29-51μg/L,回收率为98.05%-104.30%,相对标准偏差(RSD)小于4%.     

毛细管电泳-电化学发光法测定腐胺与亚精胺

基于葡萄酒发酵产生的生物胺会影响人的健康,且腐胺与亚精胺均可明显增强三联吡啶钌[Ru(bpy)32+]的电化学发光强度,建立一种以直径500μm的Pt盘为工作电极的毛细管电泳-电化学发光法测定腐胺与亚精胺含量的分析方法;该方法具有灵敏度高、线性范围广、分离效率高、分析速度快等特点。实验获得的优化条件为,检测电位:1.15 V;Ru(bpy)32+浓度5 mmol/L(pH=9.5);进样时间10 s;进样高压10 kV;运行高压:13 kV;运行缓冲液:pH9.5050 mmol/L磷酸盐缓冲溶液。结果表明:在最优条件下,腐胺在0.1 mmol/L～4 mmol/L浓度范围内与发光强度呈良好的线性关系,相关系数为0.994 9,检出限为(S/N=3)为0.1 mmol/L;亚精胺在0.05 mmol/L～2 mmol/L浓度范围内与发光强度呈良好的线性关系,相关系数为0.992 5,检出限为(S/N=3)为0.05 mmol/L。用该方法对葡萄酒样品中的腐胺与亚精胺进行了平行测定,其中亚精胺的迁移时间和峰高的相对标准偏差(RSD)分别为0.13%和7.29%,样品中没有腐胺。     

Concentration of Milk and Whey by Membrane Technologies in Alternative Cascade Modes

The aim of the present study was the evaluation of a membrane cascade comprised of ultrafiltration (UF) in series with reverse osmosis (RO) or nanofiltration (NF) in comparison to a single-stage process. It was found that the upstream UF accelerated the NF and the RO, whereby the effect was more distinct for the NF. The maximum volume reduction ratio (VRR) during skim milk and sweet whey concentration could be increased by 78 and 96%, respectively, by substituting a single NF by an UF-NF cascade. The replacement of a single RO by a UF-RO cascade during concentration of skim milk slightly increased the VRR by 3%. However, the energy demand could be reduced by approximately 16%. For the concentration of sweet whey, it was found that it is more advantageous to conduct the RO at a higher transmembrane pressure (TMP) instead of applying an UF-RO cascade.     

低聚异麦芽糖产品中主要组分的毛细管电泳分析方法

在未涂渍的石英毛细管中 ,以 75mmol/L硼砂 (pH 1 0 5 )为运行电解质 ,在检测波长 2 1 4nm、分离电压 1 5kV下对低聚异麦芽糖的主要组分的α 萘胺衍生物进行了快速分离测定。结果表明 ,该方法重现性好 ,迁移时间和峰面积的相对标准偏差分别在 0 5 %和 2 0 %以内。异麦芽糖、异麦芽三糖、潘糖浓度在 0 0 0 5～ 1 0 0 0mg/mL范围内 ,含量均与其峰面积之间呈现良好的线性关系。该法灵敏度高 ,成本低 ,为测定低聚异麦芽糖产品中主要组分提供了一种高效快速的方法     

毛细管电泳法分析贝类食品中的软骨藻酸

为监测贝类食品的食用安全，建立了毛细管电泳/紫外检测法定量测定贝类食品中软骨藻酸的分析方法，结果表明：软骨藻酸在0.2～50μg/mL范围内具有良好的线性关系，相关系数r=0.9990；RSD=2.56%，方法检出限为0.034μg/g，在3个水平上对实际样品进行标准添加，回收率分别为96.80%，97.10%和96.85%，该方法简单，灵敏，高效，成本低，对记忆损失性贝类毒素的检测和监控具有重要意义。     

毛细管电泳法在反式脂肪酸检测中的应用

对常用于反式脂肪酸检测的区带毛细管电泳和胶束毛细管电动色谱技术的原理和特点进行了简要的介绍,并对食品中反式脂肪酸检测应用进行了综述。     

毛细管电泳法分析蜂胶中的黄酮类化合物(英文)

使用毛细管电泳法(CE)检测蜂胶中11种黄酮类化合物:金合欢素、芹菜配基、兰肉桂酸、黄良姜精、阿魏酸、橙皮甙、毛地黄黄酮、柑桔黄素、槲皮素、白藜芦醇、芦丁。确定了一些试验参数的优化条件,如:pH、缓冲溶液浓度、分离电压、进样时间以及UV检测器波长等。用H3BO3-Na2B4O7缓冲溶液(40mmol/L,pH8.85)在206nm波长条件下,各分析物可在19min内测出。相对标准偏差(RSD):8次进样的迁移时间为0.1%～0.3%;峰面积为3.0%～9.7%;各检测限(S/N=10)范围为0.1～0.4μg/ml;回收率为84%～110%。方法简单、灵敏,重现性好,用于蜂胶黄酮类化合物分析结果准确。     

毛细管电泳检测苦荞芽中的黄酮类化合物

用毛细管电泳-电化学检测的方法分析了苦荞麦芽中黄酮类物质,测定了表儿茶素、芦丁、槲皮素的含量。以直径为300μm的碳圆盘电极为工作电极,50 mmol/L硼砂溶液(pH=8.5)为运行缓冲液,对上述3组分的分离检测条件进行优化研究。在优化条件下,3组分可在12 min内完全分离,检出限分别为1.83×10-7,2.9×10-8,1.00×10-7g/L。并运用此法对自助生产的两种苦荞麦芽样品中的黄酮类物质进行跟踪测定,研究了萌发时间对其中营养成分的影响。