纤维素酶辅助水蒸气蒸馏提取肉豆蔻挥发油的品质及其活性评价

该试验采用纤维素酶辅助水蒸气蒸馏和传统的水蒸气蒸馏提取肉豆蔻挥发油,通过对提取率、感官特征、理化性质、化学成分、主要官能团结构及热力学性质进行测定,以比较不同提取方法对肉豆蔻挥发油成分和性质的影响。结果表明,纤维素酶辅助水蒸气蒸馏法的提取率明显高于水蒸气蒸馏法;扫描电镜观察表明,纤维素酶对原料细胞壁的水解是促进酶法辅助快速提取的主要原因。纤维素酶辅助水蒸气蒸馏提取没有对肉豆蔻挥发油的品质产生影响。此外,2种方法提取的肉豆蔻挥发油均有清除NaNO₂的能力和阻断亚硝胺合成的作用,且在一定范围内具有量效关系。因此,纤维素酶辅助水蒸气蒸馏法提取肉豆蔻挥发油的工艺具有可行性。     

微波水蒸气法提取八角茴香挥发油

采用微波水蒸气蒸馏法提取八角茴香挥发油,并与水蒸气蒸馏法进行比较.结果表明,微波水蒸气蒸馏法的提取率与水蒸气蒸馏法相等,但提取时间为水蒸气蒸馏法的一半.气相色谱质谱联用(GC/MS)对所提取的挥发油进行化学成分分析,微波水蒸气蒸馏法所得挥发油成分与水蒸气蒸馏法相同,但含有较多的单萜类含氧化合物,挥发油的主要成分反式-茴香脑的含量为水蒸气蒸馏法的1.5倍.     

不同蒸馏方法提取辛夷挥发油的比较分析

采用水蒸气蒸馏法与同时蒸馏萃取辛夷挥发油,用气相色谱-质谱(GC-MS)联用方法进行了化学组分的测定和分析比较,水蒸气蒸馏法所得挥发油主要成分为30种,独有成分为玫瑰醚、乙酸松油酯、乙酸冰片酯。同时蒸馏法所得挥发油主要成分为30种,独有成分为萜品油烯、草蒿脑、1-羟基-1,7-二甲基-4-异丙基-2,7-环癸二烯。两种方法共有成分28种,含量较高的为蒎烯、β-蒎烯、桉叶油醇、芳樟醇、左旋樟脑、α-松油醇、α-石竹烯、(E)-β-金合欢烯、香叶烯、杜松油烯、α-毕橙茄醇、金合欢醇。水蒸气蒸馏法所得挥发油颜色浅黄,平均出油率为1.3%。同时蒸馏法所得挥发油颜色淡黄,平均出油率为1.5%。同时蒸馏萃取法无论从香气品质,含量,提取率均略高于水蒸气蒸馏法。     

龙须菜挥发油的提取及抗菌抗虫活性研究

分别采用直接水蒸气蒸馏法和溶剂提取-水蒸气蒸馏法提取龙须菜(Gracilaria lemaneiformis)挥发油,并进行气相色谱-质谱法(GC-MS)分析和抗菌抗虫活性研究。结果显示:相比于直接水蒸气蒸馏法,溶剂提取-水蒸气蒸馏法提取的龙须菜挥发油中气味阈值较低的醛类成分相对含量低至0.20%,而营养保健价值高的羧酸及酯类含量达到21.54%。龙须菜挥发油对大肠杆菌O157(Escherichia coli O157)、金黄色葡萄球菌(Staphylococcus aureus)、沙门氏菌(Salmonella enterica)、单增李斯特菌(Listeria monocytogenes)和副溶血性弧菌(Vibrio parahemolyticus)5种常见致病菌均有一定的抗菌活性;溶剂提取-水蒸气蒸馏法和直接水蒸气蒸馏法提取的龙须菜挥发油对卤虫的半数致死量(LD50)分别为0.126,0.162mg/mL。     

微波辅助提取-气相色谱-质谱联用快速分析花椒挥发油

建立微波辅助提取-气相色谱-质谱联用快速分析花椒挥发油的方法。采用微波辅助提取-水蒸气蒸馏法(MAE-SD)提取挥发油,正交试验设计优化微波辅助提取条件,气相色谱-质谱联用分析挥发油的化学成分和理化性质,同时将微波辅助提取与传统水蒸气蒸馏法进行比较。结果表明：MAE-SD的最佳工艺为微波功率400W、加水量15mL/g、浸泡30min,提取20min;经GC-MS分析,分离得到137种成分,质谱鉴定相似度在90%以上的化合物59种;根据峰面积归一法,相对含量较高的成分有桧萜(3.72%)、β-月桂烯(8.34%)、枞萜(15.15%)、松油烯(3.65%)、桉树脑(6.25%)、α-蒎烯(4.95%)、β-芳樟醇(3.05%)、4-萜品醇(10.48%)、松油醇(3.55%)、α-松油醇酯(4.09%);与水蒸气蒸馏法相比,挥发油的成分种类和理化性质接近,但相对含量存在一定差异。MAE-SD可快速高效提取挥发油类成分,联合GC-MS可对挥发油进行快速分析。     

花椒挥发油超临界CO2萃取的工艺优化及GC-MS分析

本文以花椒油得率为指标,通过响应面法优化超临界CO_2法萃取花椒挥发油工艺,并利用GC-MS分析挥发油的成分,同时以水蒸气蒸馏法作对比。结果表明,当温度42℃,压力30 MPa,提取180 min时,超临界CO_2法的得率高达12.70%,是水蒸气蒸馏法得率的2.27倍。GC-MS分析发现两种提取方法所得挥发油的组成相似,含量差异较大,主要成分有花椒油素(32.99%/10.56%)、芳樟醇(4.68%/4.84%)、桉叶油醇(3.92%/5.84%)、α-松油醇(4.55%/7.04%)、4-萜烯醇(2.95%/10.42%)、乙酸松油酯(5.19%/7.24%)、薄荷酮(5.40%/4.41%)、茴香脑(2.91%/3.73%)等,其中超临界CO_2法所得挥发油中的花椒油素含量最高,达到32.99%。这说明与传统的水蒸气蒸馏法相比,超临界CO_2萃取法的提取效率更高,而且所得挥发油含有高含量的花椒油素,这为花椒油素的提纯,花椒挥发油的开发利用提供了参考。     

武陵青花椒壳挥发油成分及脂肪酸分析

分别采用水蒸气蒸馏法和同时蒸馏萃取法提取武陵青花椒壳中的挥发油成分,提取率分别为6.4%和8.5%。再用气相色谱-质谱法(GC-MS)对挥发油成分进行分析,用峰面积归一化法确定各组分的相对含量。两种方法均鉴定出43种化合物,其中水蒸气蒸馏法以β-芳樟醇(66.91%)、反式-橙花叔醇(6.28%)、D-柠檬烯(5.24%)、4-萜烯醇(2.6%)为主,同时蒸馏萃取法以β-芳樟醇(64.32%)、D-柠檬烯(5.97%)、反式-橙花叔醇(4.17%)、反式-9-十八烯酸(3.09%)为主。同时对挥发油进行甲酯化,然后用GC-MS对挥发油中含有的脂肪酸进行了分析,共分离鉴定出6种脂肪酸。结果表明:两种方法提取的挥发油的组成及含量存在差异,挥发油中主要为不饱和脂肪酸。水蒸气蒸馏法对无极性和弱极性的萜烯和萜醇类化合物提取效果较好,而同时蒸馏萃取法适于各种极性化合物,对极性稍强的脂肪酸和酯类有较好的提取效果。     

啤酒糟挥发油化学成分的GC-MS分析及对DPPH自由基的清除作用

采用水蒸气蒸馏法提取啤酒糟挥发油,利用气相色谱-质谱联用法(GC-MS)分析挥发油的化学成分,并以面积归一化法测定各成分的相对含量。从挥发油中共鉴定出38个化合物,占挥发油总量的91.09%,含量较高的成分有棕榈酸(48.90%)、亚油酸(26.10%)、肉豆蔻酸(3.02%)、硬脂酸(2.74%)、糠醛(1.47%)、苯乙醛(0.94%)。利用分光光度法测定啤酒糟挥发油对DPPH自由基的清除作用,其清除作用明显,清除率与样品量呈量效关系,25%挥发油IC50值为50.53μL。     

鼠曲草挥发油的提取及GC-MS分析

用水蒸气蒸馏法提取鼠曲草挥发油,采用minitab软件对鼠曲草挥发油的提取工艺进行响应面分析,利用气相色谱-质谱联用(GC-MS)对挥发油成分进行分析.结果表明:从鼠曲草挥发油中分离鉴定了25个组分,占总峰面积含量的98.69%,主要含长链脂肪酸及其衍生物.主要挥发性成分的面积归一化法含量为:棕榈酸38.30%,亚油酸16.70%,亚油酸乙酯7.44%,肉豆蔻酸6.33%,油酸4.86%,硬脂酸2.28%,6,10,14-三甲基十五烷-2-酮2.83%,十五烷酸1.72%等.     

黄金茶挥发油提取工艺优化、成分分析及抗氧化研究

目的:优选黄金茶挥发油提取的最佳工艺,并对黄金茶挥发油进行成分分析、抗氧化研究。方法:通过正交试验设计优化微波辅助水蒸气蒸馏法提取挥发油工艺;通过气相色谱-质谱（GC-MS）分析黄金茶挥发油的化学成分;以DPPH自由基、还原力和金属离子螯合能力为指标评价黄金茶挥发油的体外抗氧化能力。结果:微波辅助水蒸气蒸馏法提取黄金茶挥发油的最优工艺为微波时间10 min,料液比1: 25 g/mL,水蒸气蒸馏时间5 h,在此条件下提取黄金茶挥发油得率为1.7792%。黄金茶挥发油中鉴定出21种化学物质,其中成分主要为酯类和萜类化合物,（1-甲基-4-丙-1-烯-2-基环己基）乙酸酯的含量达到50.67%,其次是α-蒎烯（6.92%）、α-乙酸松油酯（5.77%）、环氧化蛇麻烯II（3.96%）、伪柠檬烯（3.21%）、右旋大根香叶烯（3.12%）等。抗氧化实验显示黄金茶挥发油具有抗氧化作用,清除DPPH自由基的IC₅₀为81.6 mg/mL,在10 mg/mL时与阳性对照BHT还原力接近,对金属离子螯合能力的半数抑制浓度为17.16 mg /mL。结论:本文采用微波辅助水蒸气蒸馏法对黄金茶挥发油的提取条件进行了优化,通过GC-MS分析了黄金茶挥发油的成分,并证实该挥发油具有抗氧化作用。     

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