植物次生代谢产物定量分析方法研究进展

植物次生代谢产物是食品、香料与色素等的重要来源。定量分析是植物次生代谢产物研究、开发与生产的重要环节。本文介绍了植物次生代谢产物样品制备方法与含量、浓度测定方法的研究进展,讨论了不同定量分析方法的优缺点,分析了定量分析中的常见问题,在此基础上提出了植物次生代谢产物定量分析方法研究的发展策略。     

植物次生代谢与烟草香味物质

介绍了植物次生代谢的几种途径和主要的次生代谢产物,以及各种代谢途径同烟草香味物质之间的关系;阐述了分子生物学在次生代谢方面的研究进展,包括代谢途径调控的细胞水平和分子水平的研究和应用,并对次生代谢在烟草生产方面的作用作了展望.     

微生物酪氨酸解氨酶的研究进展

微生物转化生产次生代谢物质是重要的方式,但已知的微生物中未发现次生代谢物质的前体物质肉桂酸-4-羟基化酶(C4H)和香豆酸,这限制了微生物转化生产一些次生代谢产物。酪氨酸解氨酶(TAL)能跳过C4H将L-酪氨酸(L-Tyr)转化为香豆酸,为此对微生物来源的TAL的酶学性质、晶体结构、催化机制及TAL基因工程方面的研究进行了阐述,发现了TAL研究中存在的问题并初步提出了解决思路。     

中科院上海生科院揭示植物花青素合成调控机理

正中国科学报讯中科院上海生命科学研究院植物生理生态研究所黄继荣课题组,通过解析赤霉素信号转导途径中关键因子DELLA蛋白调控花青素合成的分子机理,揭示了植物通过调控次生代谢产物合成适应环境变化的新机制。相关成果日前发表于《分子植物》。大量的研究表明,植物抵御环境胁迫的强大武器是产生种类丰富的次生代谢产物。花青素     

中科院上海生科院揭示植物花青素合成调控机理

正中科院上海生命科学研究院植物生理生态研究所黄继荣课题组,通过解析赤霉素信号转导途径中关键因子DELLA蛋白调控花青素合成的分子机理,揭示了植物通过调控次生代谢产物合成适应环境变化的新机制。相关成果日前发表于《分子植物》。大量的研究表明,植物抵御环境胁迫的强大武器是产生种类丰富的次生代谢产物。花青素不但有助于植物抵御     

真菌诱导子在长春花培养体系中的应用

大多数长春花生物碱具有特殊的生物活性,并广泛应用于各种疾病的治疗。真菌诱导子可快速、专一地诱导植物特定基因的表达,从而活化特定次生代谢途径、使目的次生代谢产物积累量增加。研究表明,真菌诱导子对长春花次生代谢产物的生物合成有一定的调控作用。本文介绍了真菌诱导子的概况,总结了真菌诱导子在长春花培养体系中的应用现状,为研究药用植物次生代谢的调控提供了新的研究方向、研究思路和方法。     

保加利亚乳杆菌对绞股蓝皂苷Gypenoside XLⅥ的微生物转化

目的：分析绞股蓝皂苷Gypenoside ⅩLⅥ的微生物转化产物。方法：利用益生菌德氏乳杆菌保加利亚亚种的脱脂牛奶培养基对Gypenoside ⅩLⅥ进行微生物转化,并利用液相色谱离子阱飞行时间串联质谱方法鉴定Gypenoside ⅩLⅥ的微生物转化产物。结果：Gypenoside ⅩLⅥ的微生物转化产物为绞股蓝皂苷Gypenoside L、Gypenoside LI、Damulin B 和Damulin A。结论：通过微生物转化方法可以获得更多天然产物活性成分。     

次级代谢产物菌种改良的策略和手段

从抗生素入手 ,介绍了次生代谢产物菌种改良的策略和手段 ,从代谢工程角度讨论了在初级代谢产物育种中行之有效的设计育种“五字策略” ,以及在次生代谢产物生产菌种选育方面的应用前景 .     

功率超声富集植物性食品次生代谢产物的研究进展

植物次生代谢产物(plant food secondary metabolites,PSMs)具有抗氧化、抗癌症和心血管等疾病的功能。超声(ultrasound,US)作为非热处理技术在食品工业中得到了广泛的应用。最近的报道表明,超声可以作为非生物诱导子,用于植物生物活性分子的生物合成和积累。使用US对水果蔬菜进行清洗或净化,会对果蔬产生生理压力,从而刺激活性氧(reactive oxygen species,ROS)的产生,而ROS会引起PSMs关键代谢酶的表达和活性的改变,从而富集PSMs。本文综合国内外相关文献,对利用超声技术富集植物次级代谢产物的研究进行综述,主要介绍了超声诱导多酚化合物、萜类生物合成的规律及其机制,并对其存在的问题进行了讨论,同时展望了超声技术在植物次生代谢产物富集上的应用,以期为超声生物学效应的研究提供参考。     

植物多酚及其提取方法的研究进展

植物多酚是一类在自然界中分布广泛的植物次生代谢产物,具有多种生理功能。本文就植物多酚的定义、常见的几种多酚类物质以及多酚的提取方法做了简单的介绍。     

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