正交法优化海带岩藻多糖提取工艺

目的 研究岩藻多糖的提取工艺.方法 采用正交优化法,以海带为原料,最佳组合为料液比(1 g:20mL),温度80℃,提取3次,提取时间10 h.结果 岩藻多糖得率25%,经柱层析纯化,纯度达93%.结论 此工艺操作简便,成本较低.     

海带岩藻多糖的提取工艺优化及初步结构分析

采用高压均质与复合酶结合的方法提取海带岩藻多糖,在单因素实验的基础上,选料水比、酶用量、酶作用pH为自变量,以岩藻多糖得率为响应值,利用Box-Behnken实验设计和响应面分析法,优化得岩藻多糖最佳提取工艺条件为:料水比1∶35,酶解pH5.32,酶用量为2.5%,在此条件下,岩藻多糖得率为14.53%±0.05%;利用HPGFC测定岩藻多糖分子量为639、248、79ku;利用IC-PAD检测岩藻多糖的各组分及含量为:岩藻糖42.81%、鼠李糖1.95%、阿拉伯糖1.57%、半乳糖31.35%、葡萄糖3.30%、木糖5.56%、甘露糖13.30%。     

海带岩藻多糖的水提制备及其抗氧化活性研究

以热水浸提后乙醇沉淀的方法从海带中提取制备岩藻多糖。通过单因素试验和正交优化试验确定最佳提取工艺,可获得岩藻多糖最大提取率为4.99%,硫酸- 苯酚法测定多糖的含量为96.9%。多糖提取物对羟自由基、超氧阴离子自由基的清除作用,还原力测定以及在模拟胃液条件下对NO2 的清除实验结果表明,海带中岩藻多糖提取物具有较强的体外抗氧化性能,且随着多糖质量浓度的增大,其抗氧化活性整体呈逐渐增强趋势。     

低砷岩藻多糖的制备技术

介绍一种低砷含量的岩藻多糖制备技术:以羊栖菜为原料,在传统酸提岩藻多糖工艺的基础上,增加去除浸泡酸溶液及乙醇沉淀纯化岩藻多糖2个步骤,并对这2个步骤进行条件优化。去除浸泡酸溶液的最佳处理条件为使用5倍体积、浓度1%的柠檬酸溶液浸泡藻体,浸泡温度50℃、浸泡4 h后去除浸泡酸溶液,并使用等量的纯水洗涤一遍,然后补充等量的纯水。乙醇沉淀纯化岩藻多糖的最佳条件是:向浓缩液中加入乙醇,使乙醇浓度达到35%,静置30 min,即可离心去除沉淀,上清液浓缩去除乙醇后直接喷雾造粒。使用优化后的工艺进行提取,岩藻多糖中总砷含量由传统酸提工艺的40 mg/kg降低到(0.5~1)mg/kg,且产品得到进一步纯化,L-岩藻糖含量由20%提高到35%以上。     

酸法提取海带中岩藻聚糖硫酸酯的研究

研究了海带岩藻多糖的提取、影响因子,岩藻多糖的分离最适条件为：温度80℃,浸提时间10h,料液比为1：8.经浓缩后,再用终φ（乙醇）=60%醇析获得粗品.同时对其红外光谱性质作了研究.     

响应面法优化鹿角菜中岩藻多糖的超声波辅助提取工艺

采用超声波辅助提取鹿角菜中岩藻多糖,以岩藻多糖提取率为指标,研究超声时间、液料比、水浴温度和水浴时间4个参数对提取效果的影响,并采用Box-Benhnken设计(BBD)来优化提取工艺,确定提取条件为超声时间60 min,液料比51 m L∶g,水浴温度91℃,水浴时间5 h。在此条件下,岩藻多糖提取率达到5.961%,与理想预测值(5.993%)相比,相对误差小于5%;与传统水提法相比,提取总时间缩短了2.4 h,多糖提取率提高了0.79%。通过自由基体系评定发现,岩藻多糖具有较强的抗氧化活性,且还原力随着质量浓度的增加不断提高,对羟自由基(·OH)、超氧阴离子自由基(O~-_2·)和1,1-二苯基-2-三硝基苯肼(DPPH)自由基的半数抑制浓度IC_(50)分别为0.346、0.893和0.128 mg/m L;但与Vc相比,对羟自由基、超氧阴离子自由基清除作用较弱,但对DPPH的半数抑制浓度IC50小于Vc。     

超声辅助提取雨生红球藻渣多糖工艺优化

以提取过虾青素后的雨生红球藻渣为原料,采用超声辅助热水浸提法提取藻多糖。在单因素实验基础上,通过正交实验设计对雨生红球藻多糖提取工艺进行优化,并与传统的热水浸提工艺进行对比。结果表明,雨生红球藻多糖的最佳提取工艺为:超声功率400 W,超声时间30 min,水浴温度90℃,水浴时间3 h,料液比1∶25,在此条件下多糖得率为3.48%,得率比传统法提高了27%。超声辅助热水浸提法是雨生红球藻多糖提取的有效途径,为藻多糖的进一步研究提供基础,为雨生红球藻渣的综合开发利用提供理论依据。     

正交实验优选盐生藻多糖的提取工艺

以盐生藻为原料,盐生藻多糖得率为指标,运用稀酸、稀碱和蒸馏水为提取剂提取盐生藻多糖,得出合适的提取剂为稀酸.进一步的正交实验表明,盐生藻多糖的最适提取工艺为:提取75min,pH=4,固液比为1∶70,温度为95℃.     

纤细裸藻多糖提取工艺优化及其吸湿性、保湿性

以纤细裸藻为原料,利用超声波辅助法对纤细裸藻多糖进行提取。在单因素试验的基础上,以十二烷基硫酸钠（sodium dodecyl sulfate,SDS）浓度、超声时间以及料液比为自变量,多糖得率为响应值,基于Box-Behnken中心组合原理采用响应面法优化提取工艺。试验结果表明,纤细裸藻多糖的最佳提取工艺为SDS浓度20g/L,料液比1∶20（g/mL）,超声时间17 min;在此条件下纤细裸藻多糖的得率为35.28%。所得到的纤细裸藻多糖的吸湿性为19.07%（相对湿度81%）,在硅胶环境中的保湿性为46.16%,表明纤细裸藻多糖具有一定的吸湿和保湿性能。     

岩藻多糖的功能特性及其在食品中的应用

岩藻多糖是一种水溶性硫酸酯化杂多糖,是海带等褐藻中特有的海洋源纯天然多糖.概述了岩藻多糖的来源及提取方法、化学结构等理化性质.并对岩藻多糖的免疫调节、抗肿瘤、抗氧化、抗凝血和血栓、降血脂、抗菌、抗病毒、抗关节炎、预防胃溃疡、神经保护、调节脂肪代谢、缓解糖尿病并发症、调节骨代谢、对肠道屏障功能的保护作用、促进伤口愈合、抗衰老等多种功能特性进行阐述.系统介绍了岩藻多糖在日本、美国、韩国、中国等国家食品中的应用及研究进展.希望对进一步开发岩藻多糖在健康产业的应用有重要价值.     

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