新疆野生樱桃李(Prunus cerasifera)叶黄酮类成分研究

此项目研究了新疆野生樱桃李叶乙酸乙酯活性部位中的黄酮类化学成分。采用甲醇浸泡提取野生樱桃李叶,依次采用环己烷、乙酸乙酯和正丁醇萃取其醇提物。乙酸乙酯活性部分采用MCI (Middle Chromatogram Isolated Gel)大孔树脂柱粗分离,后续进一步采用硅胶柱、Sephadex LH-20凝胶柱,ODS (Octadecyl silane)反向硅胶柱和制备HPLC等色谱技术对其进行分离纯化,并根据化合物理化性质和核磁共振波谱(NMR)数据并与相关参考文献比对鉴定化合物结构。从野生樱桃李叶中共分离并鉴定11个黄酮类化合物,分别为:槲皮素-3-O-α-L-呋喃阿拉伯糖苷(1),槲皮素-3-O-β-D-木糖苷(2),槲皮素-3-O-β-D-半乳糖苷(3),槲皮素-3-O-α-L-鼠李糖苷(4),山柰酚-3-O-α-L-呋喃阿拉伯糖苷(5),山柰酚-3-O-β-D-木糖苷(6),山柰酚-3-O-β-D-葡萄糖苷(7),山柰酚-3-O-α-L-鼠李糖苷(8),反式-二氢山柰酚-3-O-α-L-鼠李糖苷(9),顺式-二氢山柰酚-3-O-α-L-鼠李糖苷(10),顺式-二氢山柰酚-3-O-β-D-葡萄糖苷(11)。所有黄酮类成分均为首次从新疆野生樱桃李叶中分离鉴定,槲皮素和山柰酚糖苷是其主要的黄酮类成分。     

枣叶黄酮类成分的分离鉴定及其抗氧化活性研究

对枣叶的乙醇提取物经乙酸乙酯萃取、高效液相色谱反复制备纯化,得到5种化合物。经LC-MS、1H NMR和13C NMR进行鉴定,分别为:槲皮素-3-O-洋槐糖苷(1)、槲皮素-3-O-芸香糖苷(2)、槲皮素-3-O-β-D-葡萄糖苷(3)、山奈酚-3-O-芸香糖苷(4)、槲皮素-3-O-α-L-阿拉伯糖-(1→2)-α-L-鼠李糖苷(5)。对5种黄酮单体化合物清除ABTS+、DPPH自由基的活性进行了比较,结果表明5种化合物清除ABTS+、DPPH自由基的活性呈现出相同的趋势,其中化合物3表现出最强的活性,化合物1、2、5活性适中,化合物4的活性最低。     

百子菜化学成分的分离与鉴定

从百子菜(Gynura divaricata(L.)DC.)中分离得到9个化合物,根据理化性质和波谱数据,分别鉴定为山柰酚-3-O-α-L-鼠李吡喃糖苷(1)、槲皮素-3-O-α-L-鼠李吡喃糖苷(2)、4-桉叶烯-3α,11-二醇(3)、caryolane-1,9β-dio(l4)、阿魏酸(5)、松脂素-4-O-β-D-葡萄吡喃糖苷(6)、莨菪亭(7)、姜油酮-4-O-β-D-葡萄吡喃糖苷(8)和5,5-二甲基-4-羟基-四氢呋喃-2-酮(9)。除化合物2外,其余化合物均首次从该属中分离得到。     

月桂叶中黄酮类成分的分析鉴定

利用液相色谱-四级杆-飞行时间串联质谱(LC-Q-TOF-MS),结合标准品比较、保留时间对比、多级质谱碎片和相关文献,鉴定了月桂叶黄酮的化学成分。利用液相-三重四级杆串联质谱(LC-MS/MS)在多反应监控模式(MRM)下,分别测定了黄酮化合物的含量。从我国月桂叶中分离鉴定出了16种黄酮化合物,包括牡荆素鼠李糖苷(1658.53μg/g±56.9)、芦丁(19883.54±494.33μg/g)、牡荆素(4430.87±89.72μg/g)、A-型原花青素三聚体(2281.88±78.90μg/g)、表儿茶素(148.10μg/g±2.32)、山奈酚-3-O-芸香糖苷(3491.02±47.98μg/g)、异鼠李素-3-O-芸香糖苷(6643.78±99.04μg/g)、金丝桃苷(11979.66±317.79μg/g)、山奈酚-7-O-葡萄糖苷(738.55μg/g±10.86)、紫云英苷(508.60μg/g±6.96)、槲皮素-3-O-木糖苷(2044.22μg/g±57.65)、异鼠李素-3-O-葡萄糖苷(2079.94μg/g±76.38)、槲皮苷(2079.94μg/g±61.84)、山奈酚-3-O-鼠李糖苷(6412.37±78.65μg/g)、槲皮素(1629.45μg/g±47.65)和山奈酚(364.29μg/g±2.84)。测定了月桂叶黄酮提取物清除DPPH自由基的能力,结果证明,月桂叶黄酮具有良好的清除自由基能力。     

元宝枫种仁70%乙醇提取物的化学成分分析

目的:对新资源食品元宝枫种仁中的化学成分进行研究。方法:采用硅胶、聚酰胺、凝胶(Sephadex LH-20)柱色谱及重结晶等技术进行分离纯化,综合运用质谱和波谱学方法鉴定化合物结构。结果:从元宝枫种仁70%乙醇溶液提取物中分离鉴定了12种化合物,分别为二氢去氢二愈创木基醇-4'-O-β-D-葡萄糖苷(1)、1,2,3,6-四没食子酰基-O-β-D-吡喃葡萄糖(2)、1,2,3,4,6-五没食子酰基-O-β-D-吡喃葡萄糖(3)、槲皮素(4)、山柰酚-3-O-α-L-吡喃鼠李糖苷(5)、槲皮素-3-O-α-L-吡喃鼠李糖苷(6)、槲皮素-3-O-β-D-吡喃半乳糖苷(7)、槲皮素-3-O-α-L-吡喃阿拉伯糖苷(8)、阿夫儿茶素(9)、儿茶素(10)、表儿茶素(11)、胡萝卜苷(12)。结论:经Sci Finder检索发现,化合物1~12均为首次从元宝枫种仁中分离得到,其中化合物1、2、9~11为首次从槭树属植物中分离得到。     

HPLC法同时测定枣叶中5种黄酮的含量

建立了一种枣叶中黄酮类成分定量分析的HPLC方法,并对14个品种的大枣及酸枣叶中这5种黄酮的含量进行了分析。结果得到采用Hypersil BDS C18色谱柱,以乙腈与0.1%甲酸水溶液为流动相梯度洗脱,流速1 m L/min,柱温30℃,检测波长360 nm,实现了槲皮素-3-O-洋槐糖苷、芦丁、槲皮素-3-O-β-D-葡萄糖苷、山奈酚-3-O-芸香糖苷、槲皮素-3-O-α-L-阿拉伯糖-(1→2)-α-L-鼠李糖苷5种黄酮苷的同时检测,最低检出限为1.44~2.59μg/m L,加标回收率在93.8%~105.9%之间。5种黄酮苷的含量测定结果表明不同品种的枣叶中黄酮类成分的组成和含量差异较大,其中芦丁和槲皮素-3-O-洋槐糖苷的含量较高,平均为7.83 mg/g D.W和4.61 mg/g D.W;8个品种枣叶中检测到槲皮素-3-O-α-L-阿拉伯糖-(1→2)-α-L-鼠李糖苷,平均5.32 mg/g D.W;而槲皮素-3-O-β-D-葡萄糖苷和山奈酚-3-O-芸香糖苷的含量较低,分别为0.14 mg/g D.W和0.41 mg/g D.W。     

神秘果树叶提取物降尿酸作用及其有效成分鉴定

黄嘌呤氧化酶是嘌呤代谢生成尿酸过程中的关键酶,对于高尿酸血症的发生和发展起至关重要的作用。本文构建了氧嗪酸钾诱致高尿酸血症大鼠模型,对比研究了神秘果树叶乙醇、水提取物在动物体内的降尿酸作用,采用现代色谱、波谱技术导向分离具有黄嘌呤氧化酶抑制活性的化合物。研究结果表明:神秘果树叶乙醇、水提取物在动物体内均具有一定的降尿酸作用。乙醇提取物降尿酸活性强于水提取物,并可显著增加高尿酸血症大鼠血清肌酐含量及降低尿素氮含量,呈现较好的护肾活性。从神秘果树叶中分离鉴定出3种槲皮素类化合物,包括槲皮素、槲皮素-3-O-α-L-鼠李糖苷以及金丝桃苷。3种槲皮素类化合物在乙醇提取物中的含量从高到低依次为:槲皮素-3-O-α-L-鼠李糖苷【1.74 g/(100 g)】、金丝桃苷【0.77 g/(100 g)】、槲皮素【0.17 g/(100 g)】。黄嘌呤氧化酶抑制活性从强到弱依次为:槲皮素、金丝桃苷、槲皮素-3-O-α-L-鼠李糖苷。神秘果树叶提取物以及槲皮素类化合物可用作保健食品功效因子,用以预防与治疗高尿酸血症。     

七叶一枝花的化学成分研究

目的研究七叶一枝花Paris polyphylla Smith var.chinensis(Franch.)Hara的化学成分。方法溶剂提取后,利用正相硅胶色谱,反向制备色谱,ODS柱色谱等手段对该植物的乙酸乙酯和正丁醇部位提取物进行分离与纯化,并通过核磁共振碳谱(~(13)C NMR),核磁共振氢谱(~~1H NMR)和电子轰击质谱(EI-MS)等波谱技术进行结构鉴定。结果从乙酸乙酯层和正丁醇层分离得到10个化合物,经分离鉴定为β-谷甾醇(Ⅰ),槲皮素(Ⅱ),胡萝卜苷(Ⅲ),豆甾醇(Ⅳ),偏诺皂苷元-3-O-α-L-呋喃阿拉伯糖基-(1→4)-α-L-吡喃鼠李糖基-(1→2)-β-D-葡萄糖苷(Ⅴ),熊果酸(Ⅵ),薯蓣皂苷元-3-O-α-L-呋喃阿拉伯糖基-(1→4)-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡糖苷(Ⅶ),葡萄糖(Ⅷ),薯蓣皂苷元-3-O-α-L-吡喃鼠李糖基-(1→4)-α-L-吡喃鼠李糖基-(1→2)-β-D-葡萄糖苷(Ⅸ),山奈酚(Ⅹ)。结论化合物Ⅱ,Ⅹ为种首发,化合物Ⅵ,Ⅷ为属首发。     

常春油麻藤花黄酮类化合物结构鉴定及抗氧化活性分析

目的:阐明常春油麻藤(Mucuna sempervirens)花中的黄酮类化合物及其抗氧化活性。方法:利用高速逆流色谱、制备型液相色谱等技术进行分离纯化,根据化合物的理化性质和波谱数据进行结构鉴定,并采用DPPH法测定其抗氧化活性。结果:分离得到8个化合物单体,鉴定为矢车菊3-O-6'-O-α-鼠李糖-β-D-葡萄糖苷(cyanidin3-O-6'-O-α-rhamnopyranosyl-β-D-glucopyranoside,I)、矢车菊3-O-β-D-葡萄糖苷(cyanidin 3-O-β-D-glucopyranoside,II)、槲皮素-3-O-β-D-葡萄糖苷(quercetin-3-O-β-D-glucopyranoside,III)、二氢槲皮素(dihydroquercetin,IV)、山奈酚(kaempferol,V)、异夏佛塔苷(6-C-β-L-arabinopyranosyl-8-C-β-D-glucopyranosyl apigeni,VI)、山奈酚-33-O-α-L-鼠李糖基-(1-6)-β-D-半乳糖苷(kaempferol-3-O-α-L-rhamnopyranosyl-(1-...     

平榛叶中黄酮类化合物成分的研究

利用高效液相色谱电喷雾离子化串联二级质谱(HPLC-ESI-MS/MS)技术,根据保留时间、母离子和二级质谱碎片与标准品或参考文献比对,对平榛叶黄酮成分进行了定性分析;通过多反应监控模式(MRM)对平榛叶黄酮成分进行了定量分析。共从中鉴定出12种化合物,其中11种为首次从平榛叶中发现,分别为表儿茶素(41.45±1.87μg/g,干叶)、绿原酸(3-咖啡酰奎宁酸,389.00±17.15μg/g)、丁香亭-3-O-葡萄糖苷(6169.78±209.73μg/g)、丹酚酸C(443.37±21.07μg/g)、金圣草黄素-6-C-葡萄糖苷(206.81±10.07μg/g)、金丝桃苷(槲皮素-3-O-半乳糖苷,154.44±7.63μg/g)、槲皮苷(槲皮素-3-O-鼠李糖苷,937.15±40.86μg/g)、西伯利亚落叶松黄酮-3-O-半乳糖苷(17.27±0.82μg/g)、锦葵色素-3-O-葡萄糖苷(202.74±10.04μg/g)、西伯利亚落叶松黄酮-3-O-葡萄糖苷(101.27±4.99μg/g)和山奈酚-3-O-鼠李糖苷(112.37±4.77μg/g)。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.