竹叶黄酮最新研究进展之二——竹叶酚性化学素抑制食品中丙烯酰胺形成及化解人体丙毒危害的作用和机制研究

丙烯酰胺俗称丙毒,是富含淀粉的食品在热加工过程中伴随美拉德反应形成的化学污染物,是一种公认的神经毒素和准致癌物,环氧丙酰胺是丙烯酰胺的强致癌形态.竹叶抗氧化物(AOB)和竹叶黄酮(BLF)均来源于竹叶的酚性部位,主要含黄酮和酚酸等酚性植物化学素.前者自2004年起被批准作为食品添加剂使用,后者则主要用作膳食补充剂、保健食品原料以及食品和饮品的功能性成分,二者均具有优良的生物抗氧化活性和卓越的丙烯酰胺抑制能力.本文就AOB和BLF抑制食品中丙烯酰胺形成以及防护环氧丙酰胺在体内的毒害及其作用机制进行了阐述,并展望了竹叶酚性化学素在保障食物安全和化解人类丙毒危害领域的应用前景.     

食品包装材料中丙烯酰胺在大鼠肝微粒和S9中的体外代谢研究

目的研究食品包装材料中丙烯酰胺(acrylamide)的体外代谢情况,并确证其代谢产物。方法采用肝微粒体及肝S9体外温孵法,优化代谢条件,对丙烯酰胺进行了体外代谢研究,并用液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)检测并确证丙烯酰胺的代谢物。结果通过检测结果发现,丙烯酰胺分别在肝S9和肝微粒体作用下发生显著的代谢反应,其代谢产物之一为环氧丙酰胺。结论丙烯酰胺能通过代谢转化成毒性更强的环氧丙酰胺,因此,监控食品、饮水和周围环境中的丙烯酰胺的含量对于维护人们的健康具有重要的意义。     

油炸马铃薯食品中发现丙烯酰胺的研究近况

对油炸或焙烤马铃薯食品中的丙烯酰胺含量、食品中丙烯酰胺含量的分析方法、丙烯酰胺毒性问题的最新研究结果进行了综述。现有研究结果表明 ,炸薯片、炸薯条中含有较高含量的丙烯酰胺 ,过度油炸会进一步增加薯条中的丙烯酰胺含量 ,而相应的生马铃薯原料与煮熟马铃薯中则不含丙烯酰胺。食品中丙烯酰胺含量的分析方法目前采用气相色谱 -质谱法 (GC MS)与液相色谱 串联质谱联用新技术 (LC/MS/MS) ,但食品中丙烯酰胺含量的分析方法、丙烯酰胺的毒理学研究仍在进一步发展中。     

花生红衣中B型二聚体原花青素对丙烯酰胺的抑制效果

丙烯酰胺是一种公认的神经毒素和致癌物,近年来植物多酚抑制高淀粉食物热加工过程中丙烯酰胺形成的研究是食品安全领域研究工作的一个热点。为了研究低聚体原花青素对丙烯酰胺形成的抑制效果,以花生红衣原花青素(Peanut Skin Procyanidins,PSPc)混合物经过凝胶色谱分离后得到的第二个级分PSPc-2为原料,通过反相高效液相色谱-二极管阵列检测器(RP-HPLC-DAD)分析比较其在化学模拟体系和炸薯条食品体系中对丙烯酰胺的抑制效果,并通过反相高效液相色谱-质谱联用技术(RP-HPLC-ESI-MS/MS)对PSPc-2进行鉴定。结果表明:PSPc-2在化学模拟体系和炸薯条食品体系中对丙烯酰胺的抑制均呈非线性的浓度-抑制率关系,在化学模拟体系中,PSPc-2添加浓度为0.05 mg/m L时抑制率可达66.47±1.15%,在炸薯条食品体系中PSPc-2浸渍浓度为0.1 mg/m L时抑制率可达70.59±2.34%;PSPc-2由两种B型原花青素二聚体组成。     

油炸食品中丙烯酰胺的形成及减少措施

食品在加工过程中,特别是富含天门冬氨酸和还原糖的物质在高温(120℃以上)加工过程中会产生丙烯酰胺.试验表明,丙烯酰胺对动物有致癌性、神经毒性、生殖发育毒性的作用,但还没有足够的证据表明,食品加工过程中产生的丙烯酰胺对人体有致癌性.然而丙烯酰胺作为食品加工过程中产生的不受欢迎的物质,仍应尽量减少摄入.丙烯酰胺主要存在于油炸、高温烘焙的食品中,减少油炸食品中丙烯酰胺含量的途径主要有:减少或消除形成丙烯酰胺的前体物质;抑制加工过程丙烯酰胺的生成;破坏或使食物中形成的丙烯酰胺重新反应;在食品消费前将形成的丙烯酰胺去除.同时,改变以油炸和高脂肪食品为主的饮食习惯,尽量减少或防止丙烯酰胺可能对人体造成的伤害.     

脉冲电场强化天冬酰胺- 果糖体系的研究

应用脉冲电场强化天冬酰胺- 果糖模式美拉德反应,对反应后天冬酰胺- 果糖模式美拉德反应体系的pH 值、紫外特征吸收(A294nm)、褐变程度(A420nm)、反应过程中天冬酰胺和果糖含量以及抗氧化活性进行分析,同时采用高效液相色谱(HPLC)检测产物中丙烯酰胺和5- 羟甲基糠醛(HMF)的含量。结果表明：脉冲电场能显著促进天冬酰胺-果糖模式美拉德反应,体系褐变程度、抗氧化活性与反应时间及电场强度均呈正相关,反应产物中未发现丙烯酰胺和HMF。     

QuEChERS前处理结合HPLC-MS法检测淀粉类食品中丙烯酰胺

建立了淀粉类食品中丙烯酰胺的QuEChERS前处理结合高效液相色谱-质谱的检测方法。淀粉类食品样品经过2次正己烷脱脂,水和乙腈涡旋振动提取,采取N-丙基乙二胺(PSA)净化方式,以甲醇-水(1:9,v/v)为流动相,Venusil C_(18) MP色谱柱分离,质谱电喷雾电离方式,同位素内标标准曲线法,特定质荷比m/z为72和75定量分析丙烯酰胺及内标。结果表明,丙酰酰胺的定性检出限为3.5μg/kg,定量检出限为12μg/kg,线性定量范围(0.01~2.00)μg/mL,线性相关系数(R~2)为0.9999,加标回收率在90.5%~97.9%范围,相对标准偏差小于3.0%。方法具有操作简单、快速、可靠和较低检测限等优点,成功应用于淀粉类食品中丙烯酰胺含量的检测。     

利用模拟体系探究沙棘黄酮对丙烯酰胺生成的抑制作用及其机理

本研究旨在探究沙棘黄酮对丙烯酰胺生成的抑制作用及其机理。首先利用Asn-Glu模拟体系建立沙棘黄酮抑制丙烯酰胺生成的量效关系；在此基础上，通过紫外吸收光谱、液相色谱-质谱和高效液相色谱测定美拉德反应三个阶段的产物，运用形成/消除动力学模型及机理动力学模型研究沙棘黄酮抑制丙烯酰胺生成的机理。结果表明，沙棘黄酮对抑制丙烯酰胺生成有明显的效果，最高抑制率为62.1%；通过拟合形成/消除动力学模型发现沙棘黄酮显著降低丙烯酰胺的生成速率常数a、t_cg(P<0.05)，对消除速率常数τ没有显著影响(P>0.05)，表明沙棘黄酮主要抑制丙烯酰胺的生成阶段，对丙烯酰胺的消除阶段没有影响；通过拟合机理动力学模型发现沙棘黄酮显著降低丙烯酰胺的生成速率k₂和类黑素的生成速率k₃(P<0.05)，说明沙棘黄酮主要抑制了美拉德反应的第二阶段。综上，沙棘黄酮能有效抑制中间产物向丙烯酰胺和类黑素转化，可以作为食品添加剂应用于食品加工业中。     

食品中丙烯酰胺形成途径的研究进展

丙烯酰胺是一种有神经毒性和潜在致癌性的物质,2002年首次发现在高温油炸后的富含碳水化合物食品中存在,引起了世界各国研究者的广泛关注.综述了食品高温加工过程中丙烯酰胺形成的主要途径,天冬酰胺与还原糖发生Maillard(美拉德)反应.Strecker途径和N-糖苷途径是丙烯酰胺形成的主要途径;丙烯酸途径由于受自由氨的限制,虽然在食品中常见但生成丙烯酰胺的量比较少.     

3-氨基丙酰胺在丙烯酰胺形成和消减中的作用

3-氨基丙酰胺是天冬酰胺与还原糖发生美拉德反应的中间产物,同时也是丙烯酰胺的直接前体,它在高温下脱氨形成丙烯酰胺。研究发现：3-氨基丙酰胺在转化为丙烯酰胺的同时,可与丙烯酰胺形成加合物,降低丙烯酰胺的暴露水平。为此,本研究在鉴定3-氨基丙酰胺与丙烯酰胺形成加合物的基础上,研究了不同反应条件对加合物形成的影响。研究结果表明：反应温度、时间和反应物的浓度比显著影响加合物的形成,当丙烯酰胺与3-氨基丙酰胺浓度比例为3︰5,在160 ℃下反应20 min,有47.29%的丙烯酰胺通过形成加合物被消除。     

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