基于超高效液相色谱-四极杆-飞行时间质谱法的兴安升麻甲醇提取物化学成分分析

目的：鉴定兴安升麻甲醇提取物中的化学成分。方法：采用超高效液相色谱仪分离兴安升麻甲醇提取物化学成分,四极杆-飞行时间质谱采集其一级和二级高分辨质谱数据,并用Masshunter软件对原始质谱数据进行分子特征提取,得到可能与兴安升麻相关的候选成分,根据化合物质谱裂解规律及部分标准品确证,鉴定化合物的结构。结果：共鉴定兴安升麻甲醇提取物中的38 个成分,包括苯丙素类、皂苷类,色原酮类、含氮化合物4 类成分。结论：超高效液相色谱-四极杆-飞行时间质谱可应用于升麻化学成分的鉴定。     

野地瓜茎正丁醇萃取物中主要抗氧化活性成分的筛选

探清野地瓜茎不同极性萃取物的抗氧化活性,筛选并鉴定抗氧化活性较高萃取物的主要化学成分。通过系统溶剂法对野地瓜茎提取物进行萃取,获得石油醚、二氯甲烷、乙酸乙酯、正丁醇相提取物及剩余上层被萃取水相提取物;采用1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除能力、2,2’-联氮基-双-(3-乙基苯并噻唑-6-磺酸)二铵盐(ABTS)自由基清除能力和总还原力(TRPA)试验综合评价其不同极性萃取物的抗氧化活性;结合在线高效液相色谱—质谱—二苯基三硝基苯肼(HPLC-DAD-ESI/MSn-DPPH)快速筛选并鉴定活性较高萃取物中的抗氧化活性成分。结果表明:正丁醇萃取物具有较强的抗氧化活性(P0.05),随着质量浓度的增大呈明显的剂量依赖效应,正丁醇萃取物对DPPH自由基、ABTS自由基清除能力的半数抑制浓度(IC_(50))分别为(23.28±0.21),(76.30±1.13)μg/mL。经液相色谱、质谱、文献报道和对照品的综合分析,从野地瓜茎正丁醇萃取物中筛选的3种抗氧化活性化合物为5-O-咖啡酰奎宁酸、3-O-咖啡酰奎宁酸和4-O-咖啡酰奎宁酸。     

UPLC-PDA-MS-ABTS阳离子自由基在线分析藤茶的抗氧化活性成分

采用超高效液相色谱-二极管阵列检测器-质谱-2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐阳离子自由基在线法对藤茶中的抗氧化活性成分进行定性鉴别;以Trolox为对照品,采用标准曲线法,对藤茶中的主要成分二氢杨梅素的抗氧化活性进行定量分析。结果表明,从藤茶中共鉴定出4个化合物,其中主要抗氧化活性成分为二氢杨梅素;对市售12批藤茶样本进行抗氧化活性分析,其中产于湖北恩施和福建武夷山的样本抗氧化活性最高。所建定量分析方法快捷、稳定、可靠,可用于藤茶样本的在线抗氧化分析。     

高效液相色谱-高分辨飞行时间质谱联用技术筛选中国和俄罗斯人参中的差异成分

摘 要：目的 建立高效液相色谱-高分辨飞行时间质谱联用技术筛选中国和俄 罗斯人参中人参皂苷差异化合物的分析方法。方法 采用高效液相色谱-高分辨飞行时间质谱联用技术(High-Performance Liquid Chromatography Tandem Triple-Time-of-Flight Mass Spectrometry/Mass Spectrometry,HPLC-Triple-TOF MS/MS)技术对来源于中国和俄罗斯的48例人参样品进行测定,通过高分辨飞行时间质谱分析(Triple-Time-of-Flight Mass Spectrometry/Mass Spectrometry, Triple-TOF MS/MS),对48例样品的特征峰质谱信息进行提取,通过得到的一级质谱精确质荷比和二级质谱碎片信息,结合软件数据库进行成分鉴别后,采用主成分分析(Principal Component Analysis,PCA)和正交偏最小二乘法-判别分析 (Partial Least Squares Discriminant Analysis,PLS-DA)对得到的数据进行处理,筛选差异组分。结果 经上述方法进行处理和分析后,中国和俄罗斯人参样品间的组分得到明显区分,初步筛选并鉴定出了中国和俄罗斯人参间14种差异显著的人参皂苷类化学成分。结论 本研究成功建立了基于高效液相色谱-高分辨飞行时间质谱联用技术鉴别中国和俄罗斯人参的分析方法,建立的方法准确、可靠, 可用于中国和俄罗斯人参的产地鉴别和溯源。     

远安黄茶啤酒抗氧化物质的分离与鉴定

以抗氧化活性为筛选导向,采用醇沉、溶剂萃取、大孔树脂分离和半制备型液相色谱联用技术从远安黄茶啤酒中分离出8 个具有抗氧化作用的关键组分。进一步结合超高效液相色谱-四极杆飞行时间质谱联用技术对抗氧化组分进行分析,共鉴定出8 种化合物,分别为表没食子儿茶素（(－)-epigallocatechin,EGC）、咖啡因、表没食子儿茶素没食子酸酯（(－)-epigallocatechin gallate,EGCG）、表儿茶素（epicatechin,EC）、1,2,6-三没食子酰-β-D-葡萄糖、表儿茶素没食子酸酯（(－)-epicatechin gallate,ECG）、柯里拉京（corilagin,Cor）和色氨酸（Trp）。抗氧化活性和定量研究发现,EGC、EGCG、EC、ECG和Cor是远安黄茶啤酒中的主要抗氧化物质,对酒体的抗氧化活性贡献可达54.61%。其中,EGCG的贡献值最大,其次为EGC、ECG、EC和Cor。本研究为鉴定茶啤酒中的关键抗氧化成分,实现高抗氧化啤酒产品的选择性研发提供了技术支撑。     

杨梅功能活性成分的UPLC-ESI-Q-TOF/MS分析

对杨梅中的功能活性成分进行全面的筛查。建立一个含有100余种相关化合物的"待筛查化合物数据表",使用超高效液相色谱-电喷雾-四级杆/飞行时间质谱(ultra performance liquid chromatography-electron spray ionizationquadrupole-time-of-flight/mass spectrometer,UPLC-ESI-Q-TOF/MS),分别在TOF/MS全扫描和Q-TOF/MS碎片扫描两种模式下分析杨梅样品的功能活性成分。依据精确质量在"待筛查化合物数据表"中查出可能的化合物,结合二级质谱的子离子碎裂特征对化合物进行定性分析,并对杨梅中的主要成分黄酮苷和花青素苷的质谱裂解规律进行探讨。通过该方法灵敏、快速、准确地对杨梅中的功能活性成分进行全面的定性分析,从市售杨梅样品中鉴定出28个功能活性成分,其中包括13个黄酮及其糖苷、6个花青素及其糖苷和9个酚类化合物。     

基于谱效关系的α-糖苷酶抑制剂筛选方法研究

采用以生物活性色谱为基础的谱效筛选模式,以减肥茶为研究对象,首先确认了该减肥茶对α-糖苷酶有较强的抑制活性;进一步建立了α-糖苷酶抑制剂筛选模型,并与液相色谱串联质谱相结合,对减肥茶进行谱效关系分析,从中筛选到7个对α-糖苷酶有较强的抑制活性的化合物,通过质谱进行结构鉴定。这7个化合物分别为儿茶素、儿茶素没食子酸脂、芦丁、2-羟基-1-甲氧基阿朴啡、槲皮素、荷叶碱和大黄素;最后对这7个化合物进行活性验证。建立的基于谱效关系分析对α-糖苷酶抑制剂的筛选和鉴定的方法简单、快速、准确率高。可用于对天然产物等复杂体系中活性物质的快速筛选和鉴定。     

基于超高效液相色谱-四极杆-飞行时间高分辨质谱分析酸橙果实中的生物活性成分

应用超高效液相色谱-四极杆-飞行时间高分辨质谱结合靶向和非靶向筛查方法系统分析鉴定了6个酸橙果实品种的不同部位(果皮、果肉、果汁)的生物活性物质.根据化合物的精确分子质量、质谱裂解规律、碎片离子信息,结合数据库匹配、标准品比对并参考相关文献对化合物结构进行鉴定.该实验共鉴定了84种生物活性成分,包括44种类黄酮、8种酚...     

HPLC-ABTS~+·在线法筛选细叶杜香叶部抗氧化活性成分

利用HPLC-ABTS+.在线法对细叶杜香叶中的抗氧化活性成分进行筛选和分析鉴定,结果表明:在细叶杜香甲醇提取物的乙酸乙酯萃取组分中筛选到2种抗氧化活性成分,经质谱和核磁共振波谱分析鉴定为染料木苷和槲皮素。     

在线抗氧化分析和超滤亲和液质联用技术快速筛选桂花抗氧化及抑制酪氨酸酶的活性成分

目的:研究桂花水提物的抗氧化活性及酪氨酸酶抑制活性,并初步研究其活性化学成分.方法:以DPPH·清除能力、ABTS+·清除能力和FRAP这3种抗氧化活性评价指标来衡量桂花水提物及其化合物的抗氧化能力;采用超高效液相-ABTS+·-质谱(UPLC-PDA-QDa-ABTS+·)在线法对桂花中的抗氧化活性成分进行定性鉴别,...     

Evaluation of antioxidant activity of ten compounds in different tea samples by means of an on-line HPLC–DPPH assay

Tea (Camellia sinensis), a well-known traditional beverage in China, has drawn growing attention due to its various benefits to health. In this study, an on-line assay of coupling high performance liquid chromatography separation with 1,1-diphenyl-2-picrylhydrazyl free radical reaction system (HPLC–DPPH) was applied to evaluate the antioxidant activity of different teas. Twelve main chromatographic peaks were detected in tea, and they were identified as gallic acid, 3-galloyl-quinic acid, theobromine, (−)-gallocatechin, (−)-epigallocatechin, caffeine, procyanidin dimer, (−)-epicatechin, (−)-epigallocatechin gallate, (−)-gallocatechin gallate, 1,2,6-tri-galloyl-glucose and (−)-epicatechin gallate by comparing their retention times and DAD spectra with standard compounds respectively or with reference to our previous study. DPPH assay showed that ten out of twelve investigated compounds have free radical scavenging activity, and their contents were determined or estimated. Trolox equivalent antioxidant capacities (TEACs) of the ten active components were also determined. EGCG was the most potent antioxidant with a TEAC value of 5.822. Catechin components were the major contributors to the antioxidant activity of tea; they decreased during tea fermentation and led to the reduction of antioxidant activity. Different tea samples were scientifically classified and their antioxidant activities were comprehensively evaluated by on-line HPLC–DPPH assays coupled with principal component analysis and hierarchical clustering analysis. The results indicated that the combination of the on-line HPLC–DPPH assay, principal component analysis and hierarchical clustering analysis could be suitable for the bioactivity assessment and variety characterization of tea and its derived products. Additionally, a simple and rapid method for simultaneous capture of chemical quantitative analysis and bioactivity evaluation by determining contents of the bioactive compounds was firstly established. This method could provide a comprehensive evaluation of tea.     

Isolation and Identification of Antioxidant Compounds from Ligularia fischeri

Abstract: The plant Ligularia fischeri var. spiciformis Nakai, a well-known edible medicinal herb in Korea, has been used to treat maladies such as jaundice, scarlet fever, rheumatoid arthritis, and hepatic function failure. In this research, 4 major antioxidant compounds were detected from this plant's leaves using an on-line high-performance liquid chromatography (HPLC)-ABTS screening system, which can determine the antioxidant activity based on a decrease in absorbance at 734 nm after postcolumn reaction of HPLC-separated antioxidants with the 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals (ABTS^•). In order to isolate these active compounds, a preparative HPLC was applied and their chemical structures were identified as 5-O-caffeoylquinic acid (5-CQA), 3,4-di-O-caffeoylquinic acid (3,4-DCQA), 3,5-di-O-caffeoylquinic acid (3,5-DCQA), and 4,5-di-O-caffeoylquinic acid (4,5-DCQA) by ESI/MSⁿ and ¹H NMR. These 4 isomers comprised over 10% of the dried leaves, with 3,5-DCQA being the most abundant compound. The radical scavenging activity of each isomer was also evaluated simultaneously through the on-line HPLC-ABTS method, which showed 94% antioxidant activity of the ethanol extract derived from caffeoylquinic acids. Among these isomers, 3,4-DCQA contained the most strong antioxidant activity while 3,5-DCQA accounted for the highest radical scavenging capacity due to having the highest content.     

Identification of antioxidants in Fructus aurantii and its quality evaluation using a new on-line combination of analytical techniques

A new on-line method for simultaneous identification and monitoring of antioxidants in Fructus aurantii was established by coupling high performance liquid chromatography-diode array detector-electrospray ionisation-ion trap-time of flight-mass spectrometry with post-column derivatisation and luminol–potassium ferricyanide chemiluminescence (HPLC-DAD-ESI-IT-TOF-MS-PCD-LPFCL). While the HPLC fingerprint, structural identification and radical scavenging profile were rapidly obtained by an on-line assay using ultraviolet (UV) absorption, MS and LPFCL, details of the precise substitution patterns of various structures were achieved through UV absorption using PCD addition of shift reagents. Twenty-five flavonoids were identified by either their PCD and MS data or comparison with reference substances. Data collected both from chromatograms and activity profiles of 12 samples revealed significant differences among samples from different habitats. The results showed that this method was rapid and precise, and therefore would be an effective and sensitive method for biocompounds analysis and quality evaluation for complex food and medicinal samples.     

On-line HPLC–MS–DPPH assay for the analysis of phenolic antioxidant compounds in fruit wine: Antidesma thwaitesianum Muell.

A reversed phase high performance liquid chromatography (RP-HPLC) separation coupled with an electrospray ionisation mass spectrometry detection (ESI-MS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was used for the screening of multiple antioxidant compounds in Antidesma thwaitesianum Muell. fruit wine. The active compounds were identified by comparison with authentic standards and published mass spectra. With the help of the multidimensional information of LC–ESI-MS/MS and DPPH assay, the compounds with different chemical structures could be determined in one run successfully. The antioxidant compounds were separated and identified as gallic acid, cyanidin-3-sophoroside, monogalloyl glucoside, delphinidin-3-sambubioside, catechin, caffeic acid, and pelargonidin-3-malonyl glucoside. This result shows that an on-line HPLC–MS–DPPH assay can be a powerful technique for the rapid characterisation of antioxidant compounds in plant extracts.     

Antioxidant and antilisterial activity of olive oil,cocoa and rosemary extract polyphenols

Antibacterial and antioxidant activity of polyphenols from olive oil, cocoa, and rosemary extract was tested. Antimicrobial activity against Listeria strains was assessed using broth dilution and time-kill curve methods. The 2,2-diphenyl-2-picrylhydracyl hydrate (DPPH) radical scavenging method, Folin–Ciocalteu method, and high performance liquid chromatography (HPLC) were used for phenolics identification and determination of antioxidants level. Antibacterial and antioxidant activity of main pure phenolic compounds, such as hydroxytyrosol in olive oil, epicatechin in cocoa and carnosic acid in rosemary was each compared with their extracts.     

Anthocyanin composition of cauliflower (Brassica oleracea L. var. botrytis) and cabbage (B. oleracea L. var. capitata) and its stability in relation to thermal treatments

Violet cauliflower and red cabbage were analysed for their anthocyanin profiles before and after thermal treatments. Anthocyanins are well-noted as healthy compounds due to their antioxidant properties. Samples were analysed for total anthocyanin content by using a spectrophotometric differential pH method. An MS-based method, combining high-performance liquid chromatography (HPLC) with quadrupole tandem mass spectrometry (HPLC–MS/MS) was developed, aimed to separate, identify and quantify the main anthocyanin forms. The procedure involves a rapid and efficient pre-treatment of the samples by solid-phase extraction, followed by selective determination of all compounds in a single run analysis using HPLC–MS/MS. Structural information for the identification of compounds was obtained from their fragmentation patterns (MS/MS spectra). The compounds were separated by HPLC and detected in the multiple reaction monitoring mode (MRM), which provides a high level of selectivity for targeting the analytes in vegetables. Cauliflower and red cabbage showed differences in their anthocyanin profiles: cyanidin-3,5-diglucoside was absent in cauliflower, while it was well represented in red cabbage, together with the characteristic anthocyanin of Brassica genus, cyanidin-3-sophoroside-5-glucoside. The p-coumaryl and feruloyl esterified forms of cyanidin-3-sophoroside-5-glucoside were predominant in cauliflower, while the sinapyl one was mostly present in red cabbage. Besides, the stability of cauliflower’s anthocyanin profile was evaluated in relation to thermal pre-treatments. All thermal treatments, except microwave heating, drastically reduced total cauliflower anthocyanin content. The amount of individual anthocyanins was expressed as the percentage with respect to total anthocyanin amount, spectrophotometrically measured. Significant individual changes were observed after different thermal treatment with an isomer formation.     

快速分析彝药桃树寄生抗氧化成分

目的：快速分离、鉴定彝药桃树寄生的抗氧化成分。方法：通过1,1- 二苯基-2- 三硝基苯肼(DPPH) 自由基清除实验,评价彝药桃树寄生的甲醇提取物及其二氯甲烷、正丁醇及水萃取物的抗氧化作用,利用生物活性-高效液相跟踪方法,快速分离、鉴定其有效成分。结果：从彝药桃树寄生的二氯甲烷萃取物中分离、鉴定出有效成分为松脂酚(pinoresinol)。结论：利用生物活性- 高效液相跟踪方法可以快速分离、鉴定彝药桃树寄生中的抗氧化成分,可应用于其他天然植物活性成分的快速筛选。     

Detection and activity evaluation of radical scavenging compounds by using DPPH free radical and on-line HPLC-DPPH methods

The antiradical activity of crude extracts (80% methanol, 20% water) of S. officinalis, S. glutinosa, S. sclarea and S. aethiopis was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH·) radical scavenging method. For validation of this method several well known antioxidants (ascorbic acid-6-palmitate, gallic, chlorogenic, ferulic, caffeic, uric, gentisic and vanillic acids, catechin, quercetin, epicatechin, phloridzin, rutin and naringin) were investigated additionally. In these experiments ascorbic acid-6-palmitate had highest antiradical activity. Within the group of phenolic acids gentisic acid had the highest antiradical activity comparing with the other tested phenolic acids. Uric acid, vanillic acid, phloridzin and naringin have a much lower antiradical activity. Different reaction kinetics behaviour was observed. The validated DPPH radical scavenging method was applied to the evaluation of the antiradical activity of plant extracts. The Salvia extracts showed very high antiradical activity towards the DPPH·. An on-line HPLC-DPPH method was developed using a methanolic solution of DPPH· for a rapid detection of radical scavenging components after HPLC separation. The HPLC-DPPH on-line method was also applied to a screening of several radical scavenging components in plant extracts as well as for quantitative analysis. The HPLC analysis revealed the presence of several radical scavenging components in the all Salvia extracts. This HPLC-DPPH on-line method can also be used for quantitative determination of radical scavenging compounds.     

On-line characterization of phenolic antioxidants in fruit wines from family myrtaceae by liquid chromatography combined with electrospray ionization tandem mass spectrometry and radical scavenging detection

A screening method based on high-performance liquid chromatography (HPLC) coupled on-line to a radical scavenging detection system and mass spectrometry (MS) was used to identify and characterize antioxidant compounds in two fruit wines from the family of the Myrtaceae, Syzygium cumini and Cleistocalyx nervosum var. paniala. The active compounds were identified by comparison of retention time and mass data with the authentic standards and with the published mass spectra assisted by multi-dimension information from a liquid chromatography combined with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and a radical scavenging detection. Major antioxidants found in S. cumini wine were complicated mixture of hydrolysable tannins and the fruit acids. A trace amount of an anthocyanin, malvidin -3-o-p-coumaroyl glucoside was also found. In C. nervosum var. paniala wine, the active compounds were identified as hydrolysable tannins and their derivative i.e. caffeoylquinic acid, gallic acid, ellagic acid and methoxymethylgallate.     

Identification of antioxidant compounds of Mucuna sempervirens by high-speed counter-current chromatographic separation-DPPH radical scavenging detection and their oestrogenic activity

High-speed counter-current chromatography (HSCCC) was used to separate an ethanolic extract of leaves of Mucuna sempervirens into fractions which were then detected their antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The fractions were grouped into seven larger fractions (components) based on their antioxidant activity. The seven components were isolated by preparative HPLC to yield 12 flavonoids and two phenolic acids identified by electrospray ionisation mass spectrometry and nuclear magnetic resonance analyses. The oestrogenic activity of the 12 isolated flavonoids was evaluated by the luciferase assay based on the MVLN cell line. The results indicate that leaves of M. sempervirens are a flavonoid-rich resource that may supply antioxidant and oestrogenic compounds to the human body. The HSCCC separation-DPPH radical scavenging detection could be widely applied for rapid screening and isolation of antioxidants from complex plant extracts.