外标法和一测多评法测定忍冬中成分含量的 对比研究

对比研究外标对照品法与一测多评法测定传统药食两用忍冬中4种成分含量的差异。采用外标对照品法测定不同产地忍冬中4种成分的含量,分别以绿原酸和芦丁为参照物建立与其余成分的相对校正因子,实现一测多评,比较外标法与"一测多评"的结果,以验证"一测多评"法的准确度及可行性。结果表明:一测多评应法用于不同产地忍冬中不同类型化合物的含量测定存在显著性差异,应用于不同产地忍冬中同类型化合物的含量测定不存在显著性差异。一测多评法不适用于忍冬中不同类型化合物之间含量测定,其应用有一定局限性。     

一测多评法测定线叶金雀花及其制品中3种黄酮类成分的含量

目的:建立同时测定线叶金雀花及其制品中异荭草苷、荭草苷和阿司巴汀3种黄酮类成分含量的一测多评法(quantitative analysis of multi-components by single-marker,QAMS).方法:采用高效液相色谱法,以乙腈-醋酸水溶液为流动相,梯度洗脱,以异荭草苷为内参物,建立其与荭...     

一测多评法测定不同产地桑叶中5种黄酮类成分的含量

目的 建立一测多评法(quantitative analysis of multi-components by single marker,QAMS)同时测定桑叶中5种黄酮类成分(芦丁、异槲皮苷、紫云英苷、槲皮素、山奈酚)的分析方法.方法 采用高效液相色谱法,建立其他成分与参照物异槲皮苷的相对校正因子,通过主成分分析及...     

一测多评法测定蜂胶类保健食品中咖啡酸等4种成分的含量

目的:建立以蜂胶为单一原料的保健食品中咖啡酸、阿魏酸、异阿魏酸及咖啡酸苯乙酯的\     

一测多评法测定醋延胡索中5种生物碱的含量

目的：以延胡索乙素为内参物,建立一测多评法（QAMS）用于测定醋延胡索中5种生物碱类成分的含量。方法：采用高效液相色谱法,以乙腈-水（含0.1%磷酸, pH6.0）为流动相,梯度洗脱,根据各成分含量与色谱峰面积之间的关系,计算原阿片碱、盐酸巴马汀、盐酸小檗碱及延胡索甲素与延胡索乙素的相对校正因子（RCF）,进行方法学考察,测定5种生物碱成分含量,并采用外标法（ESM）测定含量,比较两种方法含量测定结果的差异,验证QAMS的准确性和可行性。结果：原阿片碱、盐酸巴马汀、盐酸小檗碱、延胡索甲素的相对于延胡索乙素的RCF分别为0.405、1.868、1.571、1.049;5种生物碱类成分在一定范围内线性关系良好,精密度、重复性和稳定性符合要求,平均回收率在98.38%～101.28%之间;10批不同产地延胡索经醋制后的炮制品,采用QAMS与ESM所测定5种生物碱的含量无显著差异。结论：所建立的QAMS法可用于醋延胡索中5种生物碱类成分的定量分析,结果准确、方法可行,该方法可为含生物碱类成分、多指标质量控制的中药材及炮制品的质量评价提供参考。     

HPLC法测定云南不同品种芒果中芒果苷的含量

运用高效液相色谱法测定了云南16个不同品种的芒果的叶、果皮和果肉中芒果苷的含量。结果表明,在芒果叶中芒果苷含量最高,而芒果肉中芒果苷含量最少,并且在元江虎豹牙这一品种的芒果叶中芒果苷含量最高,为芒果苷的工业生产提供了科学依据。     

一测多评法测定马齿苋中4种黄酮类成分

目的 建立一测多评法(quantitative analysis of multi-components by single marker,QAMS)同时测定马齿苋中4种黄酮类(染料木苷、木犀草素、山奈酚、槲皮素)成分含量的分析方法.方法 采用高效液相色谱法,以木犀草素为内参物,建立该成分与染料木苷、山奈酚、槲皮素的相...     

一测多评法测定羊肚菌中17种氨基酸的含量

目的:建立以谷氨酸为内参物,同时测定羊肚菌中17种氨基酸含量的一测多评法。方法:采用高效液相色谱,以乙腈-乙酸铵水溶液为流动相,梯度洗脱,以谷氨酸为内参物,建立其与其他16种氨基酸的相对校正因子（RCF）,并用相对校正因子计算16种氨基酸的含量;同时采用内标法对羊肚菌中17种氨基酸进行测定,比较一测多评法与内标法结果的差异,并对方法耐用性进行考察。结果:17种氨基酸在线性范围内线性关系良好,线性相关系数R2>0.9990,平均加标回收率在92.42%~101.16%之间,RSD在0.25%~1.94%,在不同实验条件下重现性良好（RSD<2.0%）;一测多评法和内标法测定结果的对比分析,无显著性差异（P>0.05）。在不同色谱柱、色谱体系中的相对校正因子、相对保留时间的RSD均小于2.0%,耐用性良好。结论:本文建立的一测多评法简单易操作,结果准确,节约了测定成本,为羊肚菌中氨基酸的测定提供了一种新的模式,为羊肚菌的质量评价提供有价值的参考。     

一测多评法在食品研究中的应用进展

一测多评法作为一种多成分质量评价新方法,已在食品的多成分检测中得到了成功应用,特别是解决了多成分定量分析中对照品短缺和检测成本高的问题。本文主要综述了2012年以来,使用一测多评技术在食品检测方面的研究进展,同时针对一测多评技术应用中待测色谱峰的定位、低紫外吸收化合物的检测、不同类型化合物的检测等关键问题进行了探讨和展望,以期该方法越来越广泛地运用于食品科研和生产实践中。     

一测多评法测定食用玫瑰中5种非挥发性成分的含量

目的:建立以芦丁为内参物,利用HPLC一测多评法同时测定食用玫瑰中绿原酸、金丝桃苷、芹菜素-7-O-β-D-吡喃葡萄糖苷、槲皮素的含量,并进行方法学考察。方法:以食用玫瑰为研究对象,以芦丁为内参物,确定其他四种成分相对芦丁的校正因子(RCF),通过计算样品中绿原酸、金丝桃苷、芹菜素-7-O-β-D-吡喃葡萄糖苷、槲皮素含量;同时采用外标法测定食用玫瑰中5种成分,比较一测多评法(计算法)与外标法(实测法)结果的差异,并对方法性耐用性进行考察。结果:5种成分在相应的线性范围内线性关系良好,线性相关系数R²>0.999,平均加标回收率在98.08%~99.51%,RSD在0.91%~1.87%,芦丁与绿原酸、金丝桃苷、芹菜素-7-O-β-D-吡喃葡萄糖苷、槲皮素的相对校正因子分别为1.910、0.728、0.698、0.382,且在不同试验条件下重现性良好(RSD<2.0%);6批食用玫瑰样品中5种成分按一测多评方法与外标法测定结果基本一致(RSD<1.0%)。结论:本文建立的一测多评方法操作简单,测定结果准确,能较大程度节约多成分含量测定成本,可作为一种新模式用于食用玫瑰中多成分定量,也可为全面监控食用玫瑰质量提供参考。     

Quality control method of sterols in fermented Cordyceps sinensis based on combined fingerprint and quantitative analysis of multicomponents by single marker

In this study, we established a new pattern for differentiating and comprehensively evaluating the quality of fermented Cordyceps sinensis based on high-performance liquid chromatography (HPLC) fingerprint analysis combined with similar analysis (SA), principal component analysis (PCA), hierarchical cluster analysis (HCA), and the quantitative analysis of multicomponents by single marker (QAMS). These methods indicated that fermented Cordyceps sinensis samples could be categorized into one class by PCA and HCA. The fingerprints of fermented Cordyceps sinensis were established, and four HPLC peaks were identified as ergosterol, daucosterol, stigmasterol, and β-sitosterol in Jinshuibao capsules and tablets (two products of fermented Cordyceps sinensis). Ergosterol was chosen as the internal reference substance, and the relative correction factors (RCFs) between ergosterol and the other three sterols were calculated using the QAMS method. Moreover, the accuracy of the QAMS method was confirmed by comparing the relative error between the results of the method used with those of an external standard method (ESM). No significant difference between the two methods was observed. The total sterols content in Jinshuibao products were calculated by the QAMS method, and the total sterols content of the two products were similar. This study showed that the method established herein was efficient and successful in the identification fermented Cordyceps sinensis and may further act to facilitate systematic quality control of fermented Cordyceps sinensis products.     

基于色谱法和电泳法建立饮料中索马甜的分析测试方法

索马甜作为蛋白类甜味剂在饮料等食品生产加工中被允许限量使用,目前尚无针对其检测的标准方法。分别运用超高效液相色谱法(UPLC)和SDS-聚丙烯酰胺凝胶电泳法(SDS-PAGE)对饮料中的索马甜进行分析,旨在建立相应的分析测试方法。其中,超高效液相色谱法选择大孔径的色谱填料作为分离介质,以DAD为检测器,结果显示其线性范围在10～500 mg/L内,标准曲线方程为Y=3.62568X-47.04715,所得线性相关系数为0.9983,经计算检出限为1.6 mg/L,定量限为5.3 mg/L。不同浓度水平下样品加标回收率介于80.2%～105.6%,相对偏差均在10%以内,可以实现对索马甜的定量分析。SDS-PAGE法采用12.0%的分离胶,以考马斯亮蓝染色,该方法能够实现对索马甜的定性及半定量分析,其灵敏度满足标准限值使用要求。此外,色谱法和电泳法可以相互佐证,实现对样品分析结果的确证。     

测定雌马酚的紫外法建立与应用

分别以雌马酚标准品和食用大豆异黄酮人的尿液为样品,建立一种测定雌马酚的紫外分析方法。考察方法的特性及测定结果可靠性,其结果为:检出限5×10-10g/mL,定量限15×10-10g/mL。应用于人尿液雌马酚的测定,精密度4.45%,回收率100.25%,结果可靠。新建立的紫外法达到了定量分析的要求,同时具有操作简单、快速、测定成本低的优点,适合大批量样品的测定。      

Improved methodology for quantitative determination of serum and milk proteins by single radial immunodiffusion.

Single radial immunodiffusion is a simple inexpensive method for quantitating specific proteins in a heterogenous mixture. However, it has been criticized for its lack of accuracy and repeatability; coefficients of variation of 25% have been reported by some workers. We have adopted several refinements to the single radial immunodiffusion techniques which have appeared in the literature and have made several innovations of our own. Also, as an integral part of the technique, we have developed a computer program that determines the best-fitting curve for a given set of standards, applies this curve to the raw ring-diameters, and corrects the data for plate variation and sample dilution. This program has reduced errors greatly in calculating protein concentration since all data handling beyond the recording of the precipitant ring diameter is by computer. It also allows for the storage, retrieval, and analysis of large volumes of data on many different proteins simultaneously. The overall result of this system has been to decrease the coefficients of variation to below 5% for all the milk and serum proteins tested.     

Development of a quantitative GC-FID method for the determination of sucrose mono- and diesters in foods

Sucrose esters (E 473) are emulsifiers used in foods to improve different technological properties. They should conform to the specifications laid down in Commission Regulation No. 231/2012 and be used at amounts not exceeding the maximal ones set by Commission Regulation No. 1129/2011. In order to be able to characterise commercial sucrose ester formulations and to evaluate whether they are used correctly by the food industry, a quantitative GC-FID method was developed. Standards of monoesters and diesters were isolated from commercial additive preparations because no commercial ones were available. Commercial sucrose monolaureate and in-house-synthesised sucrose diarachidonate were used as internal standards. The method showed limits of detection and quantification of 2.9 and 5.7 µg ml^–1 respectively for the monoesters and 42.8 and 129.7 µg ml^–1 respectively for the diesters. The analysed commercial additive formulations contained mainly mono- and diesters of palmitic and stearic acid with low amounts of free fatty acid and sucrose. Different food matrices were incurred with commercial sucrose esters formulations and recoveries ranged between 92% and 118% for the monoesters and between 77% and 120% for the diesters. Recovery of sucrose monoesters in cake was around 34% when no enzymatic treatment was applied, and about 64% when enzymatic treatment with Clara-Diastase was applied. This indicated that sucrose esters can interact strongly with the matrix during food production and that treatment with enzymes is essential to determine the esters’ content accurately in some classes of food products.     

Development of a quantitative GC-FID method for the determination of stearoyl-lactylates (E481/482) in foods

Sodium and calcium salts of stearoyl-lactylates (SLs) are food emulsifiers especially used in bread and bakery products to improve texture. They should be used at the lowest level at which the desired technological effect is achieved in a specific food category and at amounts not exceeding the maximums set by European Commission Regulation No. 1129/2011. In order to be able to evaluate whether these emulsifiers are used correctly but also to evaluate whether the commercial additive formulations comply with legislation, a quantitative GC-FID method was developed. An internal standard (nonadecanoyl-1-lactylate) was synthesized in-house and pure ester standards were isolated from commercial additive formulations. The method showed a limit of detection of 0.04 and a limit of quantification of 0.12 mg esters ml^?1. The commercial additive formulations analysed proved to be complex mixtures of free lactic and fatty acids together with only 50–60% esters. Besides SLs important amounts of palmitoyl-lactylates were present. Different food matrices (with low- and high-fat contents) were spiked with commercial SL formulations and recoveries ranged between 85% and 109%. Determination of SLs in commercial foods (such as bakery and bread) indicated that pre-treatment with amylase was essential to determine accurately the SL content due to the interaction of SL with the amylose.     

副溶血弧菌高灵敏免疫层析检测法的建立

目的建立一种简便、准确、高灵敏的检测副溶血弧菌的免疫层析方法。方法采用免疫层析结合纳米颗粒信号放大技术,利用间接法进行示踪标记:试纸条由粘贴在底板上的样品垫、含有副溶血弧菌检测抗体的结合垫2、含有荧光颗粒标记羊抗鼠IgG的结合垫1、含有检测线(捕获抗体)和质控线(羊抗鼠IgG)的硝酸纤维素膜和吸水纸组成。结果结合增菌培养,该方法的检测灵敏性为10~3 CFU/g,与大肠杆菌、霍乱弧菌、河弧菌、创伤弧菌、溶藻弧菌、拟态弧菌、沙门氏菌、金黄色葡萄球菌等无交叉反应。结论本研究所建立的检测方法具有高灵敏、特异、简便、快速等优势,具有潜在的实际应用价值。     

Routine and sensitive SPE-HPLC method for quantitative determination of pheophytin a and pyropheophytin a in olive oils

A sensitive and specific HPLC method with tandem diode array-fluorescence detection (DAD-FL) has been developed and validated for the simultaneous determination of pheophytin a (phy a) and pyropheophytin a (pyrophy a) in olive oils. Pigments were extracted with reverse phase solid phase extraction (RP-SPE) and subsequently analysed by HPLC-DAD-FL. The chromatographic analysis was carried out isocratically on ODS2 RP column using methanol–acetone (1:1 v/v) at flow-rate of 2.0 ml min⁻¹. Specificity of the method was assured by the simultaneous detection by UV–visible (410 nm) and FL (λ_Ex: 410 nm; λ_Em: 672 nm). Both compounds could be baseline separated within 7 min. The method was validated and applied in olive oil samples recently extracted as well as stored during 12 months. The limit of detection (LOD) defined at a signal-to-noise ratio of about 3 was ∼21.6 ng g⁻¹ for pyrophy a and ∼24.6 ng g⁻¹ for phy a under FL detection, and ∼148.0 ng g⁻¹ for both analytes under UV–visible detection. The calibration graphs were linear (r² > 0.9999; p < 0.01) between 0.25–14.00 ng μl⁻¹ for pyrophy a and 0.25–19.00 ng μl⁻¹ for phy a, under both fluorescence and UV–visible detection conditions. Recoveries of phy a and pyrophy a were over 94% as estimated by the standard addition method. Relative standard deviation for the intra-day and inter-day determination of phy a and pyrophy a were lower than 3.7% and 8.0%, respectively.