苦丁茶提取物的分离纯化、鉴定及不同萃取部位活性分析

以苦丁茶为原料，对其乙醇提取物和不同溶剂萃取部位的抗氧化活性、抗补体活性、抑制癌细胞活性进行探究，并对活性最佳的萃取部位进一步分离纯化，分析鉴定出单体化合物。抗氧化活性以总还原力、清除1,1-二苯基-2-三硝基苯肼自由基和超氧阴离子自由基的能力为指标，通过溶血实验评价抗补体活性，并采用MTT法测定对人乳腺癌细胞MCF-7的存活率，结合多种分离技术获得不同单体化合物，通过对质谱、核磁共振波谱的数据分析鉴定其化学结构。结果表明，苦丁茶乙醇提取物及各部位均具有良好的抗氧化效果，其中乙酸乙酯部位不仅在实验质量浓度范围内有较强的抗氧化活性（0.8 mg/mL均达到90%以上），还具有良好的抗补体活性（79.67±0.99）%，能很好抑制人乳腺癌MCF-7细胞增殖活性（54.8±0.26）%，对乙酸乙酯部位进行分离纯化，总共分离得到11 个单体化合物。由此可见，苦丁茶乙醇提取物和各部位均具有抗氧化、抗补体活性和人乳腺癌MCF-7细胞抑制活性，乙酸乙酯作为萃取剂时活性最佳。分离的单体化合物鉴定后多为酚类、黄酮类物质。     

铁皮石斛抗肿瘤活性成分的探究

为了探究铁皮石斛中的抗肿瘤活性成分,本研究采用乙酸乙酯、95%乙醇、水三种不同极性的溶剂依次对铁皮石斛茎的干燥粉末进行了提取,初步得到了三种提取物;初提取物在MTT细胞增殖检测结果的指引下,结合硅胶柱层析、TLC薄层分析和凝胶柱层析进行分离纯化,最终筛选出具有强抗肿瘤活性的组分。结果显示乙酸乙酯提取物经分离纯化后得到了最强抗肿瘤活性成分,其对肝癌细胞HepG-2、胃癌细胞SGC-7901和乳腺癌细胞MCF-7的增殖都有明显的抑制效果,半抑制浓度IC50依次为:0.45μg/mL、0.36μg/mL、0.34μg/mL,经波谱学数据鉴定,该化合物为金钗石斛菲醌。金钗石斛菲醌首次分离自金钗石斛,其抗肿瘤功效已经得到证实,并引起了广泛的关注,本研究成果对以铁皮石斛为原料的药品和保健食品的开发具有重要的指导意义。     

桦褐孔菌提取物抗乳腺癌活性部位筛选及成分分析

以人乳腺癌MDA-MB-231细胞筛选桦褐孔菌抗乳腺癌活性部位,并对其活性部位的成分进行初步分析。采用MTT法检测发酵液不同萃取部位抗乳腺癌活性;通过细胞形态观察进一步了解药物对细胞的影响;划痕试验检测桦褐孔菌活性部位对细胞迁移的影响;采用LC-MS/MS对活性部位的成分进行分析。结果表明,桦褐孔菌石油醚萃取部位对MDA-MB-231细胞增殖的抑制作用最强,且呈量效和时效关系,作用24 h的IC50值为76.17μg/mL;细胞形态观察显示石油醚萃取部位对乳腺癌MDA-MB-231细胞的凋亡作用随着药物质量浓度的升高而加强;划痕实验显示,药物对细胞迁移有较强的抑制作用;LC-MS/MS数据初步表征了其中的14个化学成分,初步鉴定了其中的10种成分,这10种成分首次从桦褐孔菌中得到鉴定,虽然其他4个物质未能鉴定,但亦对其相对分子质量和分子式进行了初步表征。证实了石油醚部位是桦褐孔菌抗乳腺癌MDA-MB-231细胞的主要活性部位,能抑制乳腺癌细胞增殖并诱导细胞凋亡,为进一步开发利用桦褐孔菌食药用资源提供科学依据。     

野生苦菜体外抗氧化及抑制肿瘤活性研究

以野生苦菜为原料,采用1,1-二苯基-2-三硝基苯肼(DPPH)清除能力、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)清除能力、羟基自由基清除能力和铁离子还原能力法评定其抗氧化能力,采用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)法评定苦菜提取物对雌激素依赖性人类乳腺癌细胞MCF-7和雌激素非依赖性人乳腺癌细胞MDA-MB-231的抑制活性。结果表明,苦菜甲醇提取物对ABTS、DPPH都具有较强的清除能力,且具有较强的铁离子还原能力,对雌激素依赖性人类乳腺癌细胞MCF-7和雌激素非依赖性人乳腺癌细胞MDA-MB-231均有显著的抑制活性。苦菜的甲醇提取物对MCF-7和MDA-MB-231半抑制率分别为99、107μg/mL。     

朝鲜族大酱中异黄酮的提取工艺优化及其抗肿瘤活性研究

为优化朝鲜族大酱异黄酮的提取工艺,并研究朝鲜族大酱中异黄酮的抗肿瘤活性,本实验用超声波法提取朝鲜族大酱中的异黄酮,通过单因素实验和正交实验优化其提取工艺,并通过CCK-8法对正常乳腺细胞、MDA-MB-231和MCF-7两种乳腺癌细胞的增殖抑制情况进行了测定,用Western Blot法检测了朝鲜族大酱中异黄酮处理后的两种乳腺癌细胞凋亡相关蛋白的表达情况。通过单因素和正交试验确定其最佳提取条件为提取时间80 min、料液比1:24、温度50 ℃,此时得率最高,为0.802%。CCK-8结果显示,不同浓度的朝鲜族大酱异黄酮对正常细胞无毒副作用,对MDA-MB-231和MCF-7两种乳腺癌细胞的增殖抑制情况均呈剂量-时间依赖性,且均有显著性差异(p<0.05)。对不同浓度朝鲜族大酱异黄酮处理过的两种细胞凋亡相关蛋白的检测结果显示,两种细胞随着异黄酮浓度的增加,其促凋亡蛋白Bax,caspase-3的表达量与空白对照组相比均显著上升(p<0.05),而抗凋亡蛋白Bcl-2的表达量显著下降(p<0.05),且呈现剂量依赖性。表明朝鲜族大酱异黄酮对乳腺癌细胞的生长能够起到抑制作用。     

北虫草不同极性部位体外抗肿瘤活性研究

目的 研究山东北虫草不同极性部位体外抗肿瘤活性.方法 采用系统溶剂法,分别用石油醚、乙酸乙酯、正丁醇和蒸馏水依次提取北虫草不同极性部位.以乳腺癌MCF-7细胞、食管癌ECA-109细胞和肺癌A549细胞为研究对象,用MTT法检测北虫草不同极性部位对MCF-7细胞、ECA-109细胞和A549细胞的抑制作用.结果 石油醚...     

Delphinidin抗乳腺癌EMT体外效应研究

研究飞燕草素(Delphinidin,Dp)抑制HER-2~+乳腺癌细胞(MDA-MB-453)和HER-2~-乳腺癌细胞(MCF-7)上皮细胞-间充质转化(EMT)效应。将不同浓度Dp分别处理MDA-MB-453和MCF-7细胞48 h,于倒置显微镜观察细胞形态及数量变化后,用蛋白质免疫印迹法和逆转录聚合酶链反应检测EMT标志性蛋白E-cadherin、N-cadherin、Vimentin、Fibronectin及关键调控因子锌指转录因子(Snail 1)表达。80μmol/L和100μmol/L的Dp能使MDA-MB-453和MCF-7乳腺癌细胞的E-cadherin标志蛋白表达上调,而降低与细胞迁移和侵袭能力有关的N-cadherin、Vimentin、Fibronectin及Snail因子表达水平。Dp体外具有抗MDA-MB-453和MCF-7乳腺癌EMT的效应,研究结果可为植物黄酮类化合物抗乳腺癌转移及辅助治疗提供新支撑。     

6种类胡萝卜素对人乳腺癌细胞株细胞间隙连接通讯功能影响的比较

目的：探讨类胡萝卜素对乳腺癌细胞MDA-MB-435S和MCF-7细胞的细胞间隙连接通讯功能的影响。方法：类胡萝卜素分别与乳腺癌细胞MDA-MB-435S、MCF-7共培养,划痕标记染料示踪技术检测类胡萝卜素对乳腺癌细胞间隙连接通讯功能的影响。结果：β-胡萝卜素、虾青素和番茄红素对MDA-MB-435S细胞的细胞间隙连接通讯功能具有较强的促进作用;角黄素、玉米黄素和玉米黄素双棕榈酸酯对MDA-MB-435S细胞的细胞间隙连接通讯功能的影响不明显;β-胡萝卜素、虾青素和角黄素对MCF-7细胞的细胞间隙连接通讯功能具有较强的促进作用;番茄红素、玉米黄素和玉米黄素双棕榈酸酯对MCF-7细胞间隙连接通讯功能的影响不明显。     

古尼虫草抗肿瘤活性成分的提取分离及活性测定

虫草是一类珍贵的生物资源,本实验对古尼虫草菌丝体甲醇提取物的抗肿瘤活性成分进行了研究。通过甲醇浸提、正己烷、乙酸乙酯萃取得到古尼虫草甲醇粗提物0.6194g,其得率为2.06%。将得到的甲醇粗提物用乙醚:正己烷:甲醇=5:5:1的溶液为洗脱剂进行硅胶柱层析分离纯化,获得3个组分(FB1、FB2、FB3)。通过红外光谱和核磁共振H谱对分离组分FB3进行了初步检测,结果显示为甾体类化合物。采用MTT比色法检测分离组分FB3的抗肿瘤活性,发现其对MCF-7和HL-7702细胞株有抑制作用,最强抑制率达84.54%。     

荞麦芽不同提取部位细胞毒性的实验研究

试验对荞麦芽不同极性提取部位的细胞毒性进行研究,为开发荞麦芽的保健作用提供依据。试验过程中采用体外培养的肺癌细胞(A549)、胃癌细胞(AGS)、乳腺癌细胞(MCF-7)、肝癌细胞(Hep3B)、结肠癌细胞(Colo205)为试验对象,利用SRB试验方法对荞麦芽不同极性提取部位抑制肿瘤细胞生长效果进行研究。结果:荞麦芽乙酸乙酯和丁醇提取物具有较高的抑制肿瘤细胞生长效果。在浓度为1.0mg/mL时,荞麦芽乙酸乙酯提取物显示出的抗肿瘤细胞(A549、AGS、MCF-7、Hep3B、Colo205)活性分别为70.3%、94.8%、79.6%、82.3%、73.2%。因此表明荞麦芽不同极性提取部位均具有一定的抑制肿瘤细胞生长的作用。     

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.     

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.     

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the