2种富马酸糖酯的相转移催化合成及抑菌活性研究

以马来酸酐和甲醇为原料,经酯化及异构化得到富马酸单甲酯,再经酰氯化得到富马酸单甲酯单酰氯.富马酸单甲酯单酰氯与葡萄糖或乳糖反应,在相转移催化剂四丁基溴化铵的作用下,得到具有α、β-不饱和羰基结构的富马酸葡萄糖甲酯及富马酸乳糖甲酯.抑菌活性试验结果表明:富马酸葡萄糖甲酯及富马酸乳糖甲酯对混合菌群的生长具有良好的抑制能力,其中富马酸葡萄糖甲酯的抑菌活性与富马酸单甲酯接近.     

富马酸单甲酯-3-没食子酸异戊酯的合成与性能研究

防腐剂富马酸单甲酯（MMF）与氯化亚砜作用,得到富马酸单甲酯单酰氯,优化条件为：n（MMF）：n（SOCl2）=1.0：4.0,反应时间为60min,富马酸单甲酯单酰氯产率96.5%;富马酸单甲酯单酰氯与抗氧化剂没食子酸异戊酯（i-AG）缩合,合成了兼具抗氧化性和防腐性能的化合物富马酸单甲酯-3-没食子酸异戊酯（MMF-3-i-AG）,优化条件为：n（富马酸单甲酯单酰氯）：n（i-AG）=1.0：1.0,吡啶作催化剂,m（吡啶）：m（i-AG）=1：1,110℃反应60 min,MMF-3-i-AG产率86.3%.用IR、1H NMR和元素分析对MMF-3-i-AG的结构进行了确认.研究了MMF-3-i-AG的抑菌活性和抗氧化性能,结果表明MMF-3-i-AG的抑菌能力与MMF相当,其抗氧化性能亦与PG相当.     

新型防腐剂富马酸纤维二糖甲酯的合成及抗菌特性研究

茂名学院化学与生命科学学院(茂名525000)摘要基于食品防腐防霉剂的结构-活性关系研究结果,合成了具有α,β-不饱和羰基功能基团的新型食品防腐剂——富马酸纤维二糖甲酯。抑菌活性试验结果表明:富马酸纤维二糖甲酯对牛奶酸败混合菌的生长具有良好的抑菌能力,抑菌效果优于富马酸单甲酯,接近苯甲酸。     

富马酸单苯甲酯的合成及抗菌特性研究

以马来酸酐和苯甲醇为原料,无水氯化铝为异构化催化剂,合成富马酸单苯甲酯。利用熔点测定、红外光谱和核磁共振氢谱分析对产品进行结构表征;采用单因素实验分别研究反应物摩尔比、酯化反应温度与时间、异构化催化剂、异构化催化剂用量对产物收率的影响。结果表明:以无水氯化铝为异构化催化剂、原料马来酸酐:苯甲醇:无水氯化铝配比为0.1 mol:0.1 mol:2 g、酯化反应温度60℃、反应时间3 h,此条件下富马酸单苯甲酯的收率可达74.5%。抑菌活性实验结果表明,富马酸单苯甲酯具有良好的抑菌活性。     

富马酸单甲酯的合成与抑菌活性的研究

以盐酸为催化剂,顺丁烯二酸酐和等摩尔量的甲醇醇解反应生成马来酸单甲酯,升温至90℃后,再加入催化荆盐酸,其质量是顺丁烯二酸酐质量的9.6%,异构化反应可在10min内完成并得到产物.抑菌活性实验结果表明,富马酸单甲酯的抑菌活性不受食品酸碱条件及环境温度的影响.     

新型防腐剂富马酸淀粉甲酯的合成及抑菌活性研究

富马酸淀粉甲酯（SMF）的合成分为2步：先由富马酸单甲酯（MMF）与亚硫酰氯反应生成富马酸单甲酯单酰氯（MMFC）,MMFC再与可溶性淀粉反应可得SMF。用单因素试验法确定酯化度为12．03的SMF合成工艺为：摩尔比为3：1的亚硫酰氯和MMF在100℃下回流45rain,得无色MMFC液体,收率可达92％以上。摩尔比为40：1的MMFC与可溶性淀粉在25℃反应16h,再分别经40％乙醇溶液和10％KHCO,溶液洗涤至pH=7,所得白色固体即为富马酸淀粉甲酯,其抗菌活性与富马酸单甲酯相当。     

富马酸烷·3-PG酯的合成工艺条件研究

以顺丁烯二酸酐为起始原料,与甲、乙、丙、丁、戊醇发生酯化反应制得五种马来酸单酯,马来酸单酯异构化为相应的富马酸单酯,后者与亚硫酰氯作用得到五种富马酸单酯单酰氯,用制得的富马酸单酯单酰氯酰化没食子酸丙酯(PG)分子中的3-羟基制得五种具有良好的抗氧化和抗菌活性的新型化合物—富马酸甲(乙、丙、丁、戊)·3-PG酯犤1犦。本文对每步反应的合成工艺条件进行了较详细的摸索和研究,揭示其规律,这对于没食子酯丙酯-富马酸酯衍生物的制备具有一定的参考价值。     

富马酸酯类防腐剂改性方法研究现状

富马酸酯类具有良好的抗茵活性,广泛用做食品防腐剂.近年来人们通过对富马酸酯类进行结构改造,合成具有防腐及其它综合性能的新型食品添加荆.介绍富马酸单酯、溴代富马酸二甲酯、反丁烯二酸蔗糖甲酯等富马酸酯衍生物的改性方法及改性效果的研究现状.     

新型食品抗菌剂富马酸甘油甲酯的抑菌活性研究

基于防腐防霉剂构效关系研究,合成出一种具有α、β-不饱和羰基结构的新型食品抗菌剂——富马酸甘油甲酯(GMF),并对其进行抗菌活性研究,结果表明,GMF抑菌谱较广,对常见的细菌、酵母均具有较强的抑制作用,可以有效延长其生长适应期,且效果优于常用抗菌刑苯甲酸,此外,GMF在不同pH条件下均能表现出良好的抗菌活性,是一种具有广阔开发前景的抗菌剂.     

半乳糖基甘油月桂酸单酯的抑菌活性和稳定性

研究半乳糖基甘油月桂酸单酯对食品中几种常见腐败菌的抑菌作用及其稳定性。方法：采用倍比稀释法测定半乳糖基甘油月桂酸单酯对5 种细菌和3 种真菌的最小抑菌浓度（minimum inhibitory concentration,MIC）。同时以大肠杆菌和蜡样芽孢杆菌为指示菌,研究pH值、温度、紫外线照射及NaCl质量分数对半乳糖基甘油月桂酸单酯抑菌稳定性的影响。结果：半乳糖基甘油月桂酸单酯对大肠杆菌、蜡样芽孢杆菌等5 种细菌具有较好的抑菌活性,而对黄曲霉、黑曲霉和酿酒酵母等真菌的抑制效果不明显或无抑制效果。半乳糖基甘油月桂酸单酯对荧光假单胞菌的MIC为0.078 mg/mL,对大肠杆菌、枯草芽孢杆菌、蜡样芽孢杆菌和金黄色葡萄球菌的MIC均为0.156 mg/mL。半乳糖基甘油月桂酸单酯在pH 5～8范围内具有较好的抑菌活性,经温度和紫外线照射处理后,抑菌活性有微弱下降,随着NaCl质量分数的增加,其抑菌活性显著下降。     

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