直观推导式演进特征投影法分辨枸杞类胡萝卜素的异构体

采用高效液相色谱-二极管阵列检测方法,初步分离了枸杞子中的类胡萝卜素。以乙腈-二氯甲烷(体积比为60∶40)为流动相,流速为1.0 mL/min,用C18柱从枸杞类胡萝卜素中分离出7个峰。但由于类胡萝卜素的结构多样性,尤其是顺反异构体的出现使得分离并不完全。利用所得三维数据提供的信息和化学计量学方法直观推导式演进特征投影法(HELP),对其中某些在二维色谱中被定性为单组分的峰进行解析,结果发现原来在二维色谱中被定性为单组分的峰大多是一些多组分峰。以其中第4个峰为例对其进行解析,得到了该类胡萝卜素的同分异构体色谱流出曲线及紫外光谱信息。该方法表明,化学计量学方法与现代分析手段有机结合,大大降低了此类复杂体系对色谱分离的要求,对同分异构体的分析具有一定的借鉴和指导意义。     

枸杞子中铜的测定及其浓度分布特征

用超声波辅助水提取-醇沉-溶剂萃取方法分离枸杞子得Ⅰ-Ⅷ8个组分,用石墨炉原子吸收分光光度法测定其中铜的浓度,并探讨了铜在枸杞子不同组分中的浓度分布特征。结果表明,枸杞子及其分离组分Ⅰ-Ⅷ中铜的质量分数分别是13.20、4.03、9.01、6.41、3.41、5.66、3.96、16.70、8.20μg/g,枸杞子中的铜呈现不均匀的浓度分布特征,在组分Ⅱ中浓度最高,组分Ⅳ中浓度最低。     

高效液相色谱法测定食物中的类胡萝卜素

综述了用于食物中的类胡萝卜素、类胡萝卜素酯测定的高效液相色谱方法,介绍了样品提取处理方法、色谱分离条件及检测方法。引用文献85篇。     

固相萃取-高效液相色谱法测定枸杞中的类胡萝卜素

研究了固相萃取富集和预分离,高效液相色谱测定枸杞中的类胡萝卜素的方法;枸杞中的类胡萝卜素用WatersXterraTMRP18固相萃取小柱预分离,以WatersXterraTMRP18(3.9×150mm,5μm)液相色谱柱为固定相,甲醇 四氢呋喃(4 1)为流动相分离,用二极管矩阵检测器检测,检测波长为450nm。方法标准回收率为95%～103%。用该方法测定了几种枸杞样品中的类胡萝卜素。     

番茄中类胡萝卜素及其顺式异构体的HPLC分析

建立了一种能同时快速分离、定性番茄中3种类胡萝卜素及其异构体的高效液相色谱(HPLC)方法。采用正己烷-乙醇(3∶4)对样品进行提取,甲基叔丁基醚+0.05%三乙胺-乙腈+0.05%三乙胺为流动相梯度洗脱,以Carotenoid C30柱(250 mm×4.6 mm i.d.,5μm)进行分离,检测波长为475 nm。结果表明,在优化实验条件下,番茄中有11种类胡萝卜素得到了良好分离,包括3种全反式异构体和8种顺式异构体。叶黄素、β-胡萝卜素、番茄红素分别在0.1~5.0,0.1~20,0.1~100μg/m L浓度范围内线性关系良好,相关系数均在0.99以上,检出限(LOD)分别为0.13,0.12,0.56μg/g,定量下限(LOQ)分别为0.43,0.41,1.88μg/g;日内相对标准偏差(RSD)为1.2%~5.3%,日间RSD为1.9%~7.5%,回收率分别为(88.9±6.1)%~(91.7±3.6)%,(92.3±4.3)%~(94.1±6.3)%,(102.6±4.2)%~(107.1±3.4)%。该方法具有分析时间短、灵敏度高、分离完全等优点,适用于番茄中类胡萝卜素及其顺式异构体的分析测定。     

AAS法测定枸杞子中微量锂

枸杞子是中药滋补剂。为了探求枸杞子中微量元素锂对脑、肾、新陈代谢等生理功能的作用。本文介绍了用原子吸收法对宁夏枸杞子中的锂含量进行的研究。本文使用日立518型原子吸收分光光度     

枸杞功能性成分的提取及其组成的液相色谱分析

对枸杞子中的水溶性多糖成分进行了分离提取及组成分析。采用水提、醇沉等方法提取枸杞子中的多糖成分,用Sevage法除去蛋白质后,用凝胶色谱法进行多糖的纯化,制备3-甲基-1-苯基-2-吡唑啉酮（PMP）衍生物进行液相色谱分析。结果表明,枸杞多糖由鼠李糖、阿拉伯糖、木糖、葡萄糖、半乳糖5种单糖组成,其含量分别为5．28％,17．87％,38．29％,17．82％,20．74％。     

快速溶剂萃取-高效液相色谱法测定枸杞子中四螨嗪残留量

建立快速溶剂萃取-高效液相色谱法测定枸杞子中四螨嗪残留量的方法.枸杞子样品经快速溶剂萃取,硅胶层析柱净化.分析时用C18柱(4.6 mm×250 mm,5 μm)分离,V(甲醇):V(水)=70:30为流动相,流速1.0 mL/min,检测波长277nm,参比波长324nm.该方法的线性关系良好(r=0.9999),最低检出限为0.005 mg/kg,加标回收率在81.2%～96.9%范围内,相对标准偏差小于7.7%.该方法快速、准确、简便,能够满足检测要求.     

高效液相色谱法测定藻类中的类胡萝卜素和叶绿素

提出了用高效液相色谱法测定藻类中类胡萝卜素和叶绿素的方法。采用丙国等有机溶剂提取藻类中的类胡萝卜素和叶绿素,然后在反相C18柱上进行分离。流动相选用二氯甲烷／乙腈／甲醇／水（22.5:9.5:67.5:0.5）,流速为1.0mL／min。用光度检测器检测报长为450um。叶黄素、α-胡萝卜素、β-胡萝卜素、叶绿素a和叶绿素b的平均回收串分别为99.1％,98.5％,99.4％,100.6％和99.9％,相对标准偏差分别为2.4％,5.6％,6.0％,4.1％和4.0％。     

蔬菜叶片中叶绿素a和叶绿素b的一阶导数分光光度法测定

本文提出用一阶异数分光光度法同时测定蔬菜叶片中叶绿素ａ和叶绿素ｂ的含量。讨论了同时存在于蔬菜叶片中的类胡萝卜素对两者测定的影响，并提出用适当浓度的类胡萝卜素丙酮溶液作为参比溶液，用以消除类胡萝卜素对叶绿素测定的影响。     

Determination of Individual Carotenoids in Human Plasma by High Performance Liquid Chromatography

Abstract

A high performance liquid chromatography procedure using an internal carotenoid standard, echinenone, is described. The method uses a C-18, reverse-phase column, an isocratic solvent (acetonitrile:methylene chloride:methanol, 70:20:10) and requires only thirteen minutes. Most human plasmas gave seven distinct peaks; six carotenoids are identified. The sum of seven peaks is 90 percent or more of the total carotenoids in a total lipid extract.     

反相高效液相色谱法同时测定保健品中的四种类胡萝卜素

建立了不同剂型保健品中类胡萝卜素的提取方法和同时测定保健品中4种类胡萝卜素含量的高效液相色谱分析方法。采用DiamonsilTM C18色谱柱(250 mm×4.6 mm i.d.,5 μm),以乙腈和乙酸乙酯为流动相进行梯度洗脱,洗脱程序：先以100%乙腈洗脱15 min,然后乙酸乙酯的含量在10 min 内从0增加到100%,再以100%乙腈洗脱5 min;流速1 mL/min;采用二极管阵列检测器检测,检测波长为450 nm。以外标法定量,番茄红素、叶黄素、玉米黄素、β-胡萝卜素4种组分的线性关系良好,相关系数为0.9994～0.9997,检测限为0.4～0.5g/L。片剂样品、粉状样品、油状样品的加标回收率分别为95.3%～98.7%,93.7%～98.8%,97.1%～99.2%,相对标准偏差（RSD）分别为0.89%～2.0%,0.89%～2.8%,0.42%～1.2%。该法简便、快速、准确,是保健品中多种类胡萝卜素定量测定的可靠方法之一。     

超高效合相色谱-串联质谱法快速测定枸杞中甜菜碱含量（英文）

枸杞作为传统的中药材,具有滋补肝肾、益精明目的功效,亦可作为功能性食品被广泛食用。基于超高效合相色谱-质谱(UPC~2-MS),建立了一种快速、灵敏地定量测定枸杞中甜菜碱(指标化合物)含量的新方法。采用ACQUITY UPC2BEH 2-EP色谱柱(150 mm×2.1 mm,1.7μm),以0.7 mL/min超临界CO_2-甲醇(80∶20,v/v)等度洗脱,成功分离了枸杞中的甜菜碱。在该分离过程中,0.1%(v/v)甲酸作为改性剂;背压为1.31×10~7Pa;柱温为40℃;进样体积为1μL;保留时间为3 min。质谱检测工作于电喷雾(ESI)正离子模式和选择离子监测(SIR)模式。在上述条件下得到线性回归方程。其相关系数为0.999 2,检测范围为0.5～50.0μg/mL,检出限为0.013μg/mL。随后,通过对精度、重复性、稳定性和加标回收率(平均值96.3%)的分析,验证了该方法的有效性。最后,将所建立的方法应用于11批样品的分析。结果表明,该方法可较好地用于枸杞的质量控制与分析评价。     

Determination of carotenoids in two algae species from the saline water of Kapulukaya reservoir by HPLC

The local algae species, Chlorella vulgaris and Scenedesmus regularis, from a highly saline water body of Kapulukaya Reservoir were isolated to analyze their carotenoid composition and content using HPLC method. The gradient solvent system of methanol–acetonitrile–water (84:14:2, v/v/v) and methylene chloride (100%), used to resolve a range of carotenoids from the saponified cells, proved an acceptable separation as inferred from the retention factor (k) ranging between 0.75 and 7.76 and the separation factor (α) values greater than 1. Resolution peaks assigned to carotenoids, 21 for C. vulgaris extracts and 22 for S. regularis extracts, were reached within the duration time of 45?min. Main carotenoids identified either tentatively or positively were all-trans-lutein, 9- or 9′-cis-lutein, 13- or 13′-cis-lutein, cis-lutein, All-trans-α-carotene, 9- or 9′-cis-α-carotene, All-trans-β-carotene, 9- or 9′-cis-β-carotene in the species except for all-trans-β-cryptoxanthin found only in S. regularis. Auroxanthin, neochrome, neoxanthin, and cis-neoxanthin were identified as epoxy-containing compounds. Quantitatively, C. vulgaris was distinguished to have greater amount of lutein and cis-isomers (2.74?mg/g), 77.89% while S. regularis was predominated by β-carotene and cis isomers as major component, being 80.72% (5.76?mg/g) in total carotenoids (TC). In terms of total carotenoids, the species were considered to be efficient sources for further practical applications.     

Carotenoid composition in Rhinacanthus nasutus (L.) Kurz as determined by HPLC-MS and affected by freeze-drying and hot-air-drying

Rhinacanthus nasutus (L.) Kurz (Trade name: Bai he ling zhi), a traditional medicinal herb, has been reported to possess anticancer and antioxidant activities. However, the composition of the major functional compounds, carotenoids, remains uncertain. The objectives of this study were to develop a high performance liquid chromatography-mass spectrometry (HPLC-MS) method for carotenoid composition determination in R. nasutus and for carotenoid change by freeze-drying and hot-air-drying. A total of 24 carotenoids were separated within 54 min by using a YMC C(30) column and a gradient mobile phase of methanol-acetonitrile-water (82?:?14?:?4, v/v/v) (A) and methylene chloride (100%) (B): 100% A initially, maintained for 10 min, decreased to 95% A in 25 min, 84% A in 30 min, 75% A in 37 min, 68% A in 40 min, 65% A in 47 min, and 55% A in 50 min with flow rate at 1 mL min(-1) and detection wavelength at 450 nm. The various carotenoids were identified by comparing the retention time, absorption spectra, Q-ratio and mass spectra of unknown peaks with reference standards as well as photoisomerized standards. Quantitation was carried out using an internal standard β-apo-8'-carotenal, with all-trans-lutein and its cis isomers being present in the largest amount (862 μg g(-1)) in freeze-dried R. nasutus, followed by all-trans-violaxanthin (494 μg g(-1)), all-trans-β-carotene and its cis isomers (479 μg g(-1)), all-trans-neoxanthin and its cis isomers (251 μg g(-1)), all-trans-α-carotene and its cis isomers (85.2 μg g(-1)), luteoxanthin (14.3 μg g(-1)), all-trans-zeaxanthin (3.94 μg g(-1)), β-carotene-5,6-epoxide (3.45 μg g(-1)) and all-trans-β-cryptoxanthin (1.03 μg g(-1)). Comparatively, some more carotenoids including cis-violaxanthin, luteoxanthin, cis-neoxanthin, neochrome, 13- or 13'-cis-lutein, 9- or 9'-cis-lutein, β-carotene-5,6-epoxide, 9- or 9'-cis-β-carotene, 13- or 13'-cis-β-carotene, 15- or 15'-cis-β-carotene and 13- or 13'-cis-α-carotene were generated in R. nasutus during hot-air-drying.     

非水反相液相色谱法测定枸杞子中β-胡萝卜素含量

应用甲醇－乙酸乙酯（５０５５,Ｖ／Ｖ）为流动相,在ＯＤＳ反相柱上采用外标法测定了３种不同产地枸杞子中β－胡萝卜素的含量。方法简便、快速,重现性好。β－胡萝卜素的检测线性范围为１．０～５．０ｍｇ／Ｌ,ｒ＝０．９９９８,平均回收率为９７．１％,变异系数为１．９％。     

Improved liquid chromatographic method for determination of carotenoids in Taiwanese mango (Mangifera indica L.)

An HPLC method was developed to determine the various carotenoids in Taiwanese mango (Mangifera indica L.). Initially, the peel and seed of mangoes were removed, the pulps were cut into pieces, freeze-dried, ground into powder, extracted and subjected to HPLC analysis. A mobile phase of methanol-isopropanol (99:1, v/v) (A) and methylene chloride (100%) (B) with the following gradient elution was developed: 100% A and 0% B in the beginning, maintained for 15 min, decreased to 70% A in 45 min, maintained for 15 min and returned to 100% A in 65 min. A total of 25 carotenoids were resolved within 53 min by using a C-30 column with flow rate at 1 mL/min and detection at 450 nm. alpha-Carotene was used as an internal standard to quantify all the carotenoids. All-trans-beta-carotene was present in largest amount (29.34 microg/g), followed by cis isomers of beta-carotene (9.86 microg/g), violaxanthin and its cis isomers (6.40 microg/g), neochrome (5.03 microg/g), luteoxanthin (3.6 microg/g), neoxanthin and its cis isomers (1.88 microg/g), zeaxanthin (1.16 microg/g) and 9- or 9'-cis-lutein (0.78 microg/g).     

Critical assessment of three high performance liquid chromatography analytical methods for food carotenoid quantification

Three sets of extraction/saponification/HPLC conditions for food carotenoid quantification were technically and economically compared. Samples were analysed for carotenoids α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene, and zeaxanthin. All methods demonstrated good performance in the analysis of a composite food standard reference material for the analytes they are applicable to. Methods using two serial connected C₁₈ columns and a mobile phase based on acetonitrile, achieved a better carotenoid separation than the method using a mobile phase based on methanol and one C₁₈-column. Carotenoids from leafy green vegetable matrices appeared to be better extracted with a mixture of methanol and tetrahydrofuran than with tetrahydrofuran alone. Costs of carotenoid determination in foods were lower for the method with mobile phase based on methanol. However for some food matrices and in the case of E–Z isomer separations, this was not technically satisfactory. Food extraction with methanol and tetrahydrofuran with direct evaporation of these solvents, and saponification (when needed) using pyrogallol as antioxidant, combined with a HPLC system using a slight gradient mobile phase based on acetonitrile and a stationary phase composed by two serial connected C₁₈ columns was the most technically and economically favourable method.     

Analysis of palm oil carotenoids by HPLC with diode-array detection

Palm oil carotenoids are analyzed by nonaqueous reversed-phase high-performance liquid chromatography (NARP-HPLC) with UV/vis diode-array detection. Isocratic elution with 60% acetonitrile/35% methanol/5% methylene chloride at 2 mL/min on a 25-cm C18 column results in an analysis time of 30 min. Identification is made through absorption spectra and chromatographic elution behaviors, for example, polyenic pi conjugation, dipole moment of end-groups, and oxygen function on the chromophores. At least 12 carotenoids are identified with alpha- and beta-carotene as the dominant carotenoids (1:2 ratio). Several mono- and di-epoxides of alpha- and beta-isomers and hydrocarbon carotenes are found, including the UV-absorbing phytoene identified by spectral substraction. cis-Isomerization is found and discussed in the light of spectral evidence. The effect of saponification time on the amount of extracted carotenes is investigated. Quantitation results in a combined alpha- and beta-carotene concentration of at least 506 ppm. The detection limit for beta-carotene is 31 ng.     

Improved high performance liquid chromatographic method for determination of carotenoids in the microalga Chlorella pyrenoidosa

Microalgae have become an important commercial source of carotenoids and microalgae-derived functional foods are consumed by people worldwide. Therefore, an HPLC method was developed to discern the variety and content of carotenoids in the microalga Chlorella pyrenoidosa. The microalga sample was powdered, extracted, saponified and subjected to HPLC analysis. A mobile phase of methanol-acetonitrile-water (84:14:2, v/v/v) (A) and methylene chloride (100%) (B) with the following gradient elution was developed: 100% A and 0% B in the beginning, maintained for 14 min, decreased to 95% A in 25 min, 75% A in 30 min, 74% A in 35 min, 45% A in 50 min and returned to 100% A in 55 min. A total of 32 carotenoids were resolved within 49 min by using a C30 column with flow rate at 1 mL/min and detection at 450 nm. An internal standard beta-apo-8'-carotenal was used to quantify all the carotenoids. All-trans-lutein was present in exceptionally large amount (125034.4 microg/g), followed by cis isomers of lutein (27975.3 microg/g), all-trans-alpha-carotene (2465.8 microg/g), zeaxanthin (2170.3 microg/g), cis isomers of beta-carotene (2159.3 microg/g), all-trans-beta-carotene (2155.0 microg/g), cis isomers of alpha-carotene (1766.7 microg/g), beta-cryptoxanthin (334.9 microg/g), neoxanthin and its cis isomers (199.7 microg/g), neochrome (65.2 microg/g), auroxanthin (38.5 microg/g) and violaxanthin and its cis isomers (38.1 microg/g).