响应面法优化阿魏菇多糖的超声辅助提取工艺及抗氧化活性研究

为研究阿魏菇多糖(Pleurotus ferulae polysaccharides,PfP)的超声提取工艺及体外抗氧化活性,在单因素试验的基础上,采用中心组合设计(box-behnken design,BBD)和响应面方法(response surface methodology,RSM),研究超声时间、超声温度、液料比及提取次数对PfP提取率的影响,优化PfP的超声辅助提取工艺;通过测定对Fe~(3+)还原能力和对DPPH自由基、羟基自由基(·OH)的清除能力,对PfP的体外抗氧化活性进行研究。结果显示,超声温度、超声时间以及液料比均对PfP的提取率有显著影响,其中料液比影响最大,超声时间影响最小;最佳工艺条件为:超声温度66℃、超声时间27min、液料比29∶1(mL/g)、提取2次,在此条件下PfP提取率达到14.69%。体外抗氧化试验结果表明,PfP使Fe3+还原产生的最大吸光值为0.54,对DPPH和·OH的最大清除率分别为85.61%和56.1%,其抗氧化活性均在一定浓度范围呈剂量正相关效应。     

响应面优化百里香多糖提取工艺及其抗氧化作用

利用响应面分析法对百里香多糖的提取工艺进行优化,在单因素试验基础上,选取提取pH、料液比、提取时间进行三因素三水平的Box-Behnken试验,Design-Expert 8.0软件进行试验数据分析,得到百里香多糖最佳提取条件,并对提取的百里香多糖进行抗氧化研究。结果显示,百里香多糖的最佳提取条件为料液比1∶40.8,提取时间10.5min,提取pH 13.4,在此条件下百里香多糖的提取率为5.45%;百里香多糖具有一定抗氧化活性。     

白蜡多年卧孔菌多糖提取工艺优化及其抗氧化活性

采用超声辅助水提醇沉法提取白蜡多年卧孔菌（Perenniporia fraxinea）子实体与菌丝体多糖,利用单因素试验结合Box-Behnken响应面法优化子实体与菌丝体多糖提取工艺参数,并测定其DPPH·、ABTS+·清除能力。结果表明,子实体多糖的最佳提取工艺条件为：料液比1∶60（g∶mL）、提取时间76 min和超声时间16 min,在此优化条件下,子实体多糖提取率为4.39%;菌丝体多糖的最佳提取工艺条件为：料液比1∶30（g∶mL）、提取时间101 min和超声时间16 min,在此优化条件下,菌丝体多糖提取率为6.33%。当子实体和菌丝体多糖质量浓度为2.0 mg/mL时,子实体对DPPH·、ABTS+·清除率分别为45.67%和72.89%,菌丝体多糖对DPPH·、ABTS+·的清除率分别为51.67%和75.83%。子实体和菌丝体多糖能降低植物油过氧化值（POV）,表明白蜡多年卧孔菌多糖具有一定的抗油脂氧化的能力。     

利用响应面分析法优化向日葵盘中果胶的提取工艺

通过响应面分析法对向日葵盘果胶的提取工艺进行优化。利用响应面实验设计考察提取温度、提取时间、料液比和pH值四因素对果胶提取率的影响。研究发现:提取时间、温度和pH值对提取率有显著影响,向日葵盘果胶的最佳提取条件是:提取温度为79℃、提取时间为80min、料液比0·04、pH值在3·20;向日葵盘果胶最大提取产量为0·522g/g。     

灵芝菌丝体总三萜超声辅助提取工艺优化

以灵芝菌丝体为原料,在单因素试验基础上,通过正交试验和Box-Behnken响应面设计法优化超声辅助提取灵芝菌丝体总三萜工艺。结果表明,超声辅助提取灵芝菌丝体总三萜正交试验最佳工艺为:超声功率90 W、超声时间50 min、pH 8、料液比1∶40(g/mL),在此条件下灵芝菌丝体三萜平均提取率为0.76%;超声辅助提取灵芝菌丝体总三萜响应面试验最佳工艺为:超声功率90 W、超声时间42 min、pH 8、料液比1∶30(g/mL),在此条件下,灵芝菌丝体总三萜平均提取率为1.09%,与最大预测值1.13%相差0.04%。这两种方法得到的提取工艺参数可靠,可为灵芝三萜工业化生产提供技术参考。     

豆渣多糖的提取及其抗氧化活性研究

对豆渣多糖提取的工艺条件及其体外抗氧化活性进行了研究。通过单因素试验分析了pH值、液料比、提取温度、提取时间对多糖提取率的影响。在此基础上通过正交试验得到了豆渣多糖提取的最佳工艺条件,即pH5.0,液料比35∶1,温度80℃,时间4h。体外抗氧化实验结果表明,豆渣多糖对超氧阴离子自由基和羟基自由基具有较强的清除能力,提示它在天然抗氧化剂及功能性食品领域具有很大的开发应用价值。     

响应面法优化杏鲍菇多糖提取工艺

对杏鲍菇内多糖的提取条件进行研究,首先采用单因素法对影响酶解杏鲍菇水溶性多糖含量的因素以及酶解条件进行选取,然后在单因素试验的基础上,采用响应面法对杏鲍菇多糖的提取工艺进行优化,确定杏鲍菇多糖提取工艺的最佳参数,为其进一步的开发利用提供参考,杏鲍菇经过打浆、酶解后,通过水提醇沉的方法进行多糖的提取。结果表明:酶加量、料液比、pH值、酶解温度和酶解时间对多糖的提取具有明显的影响。杏鲍菇的最佳提取工艺参数为:纤维素酶0.9%、中性蛋白酶0.2%、料液比1∶2(g/mL)、pH 5.5、酶解温度50℃、酶解时间3 h,在该条件下杏鲍菇多糖提取率为3.24%。     

酶法提取杏鲍菇多糖及抗氧化活性研究

以杏鲍菇为原料,采用水提和复合酶法提取杏鲍菇多糖,用苯酚-硫酸法测定多糖含量,探讨提取工艺条件,用Sevag法脱蛋白对杏鲍菇多糖进行纯化,并对其抗氧化活性进行研究。试验结果表明,水提最佳条件为料液比1∶20(g/m L)、时间50 min、温度30℃,多糖提取率为13.64%;酶法提取最佳工艺条件为酸性纤维素酶2.0%、酸性蛋白酶1.5%、料液比1∶20(g/m L)、温度30℃、时间50 min,多糖提取率为15.86%;复合酶法比水提法提取率提高了16.28%。采用Sevag法对杏鲍菇粗多糖进行纯化,多糖纯度提高了40.37%。杏鲍菇粗多糖,精多糖对OH·、O2-·和DPPH均有较强的清除能力,且随其浓度的增加清除率逐渐增大;相同质量浓度粗多糖的清除效果大于精多糖,但都明显低于VC。     

茯苓菌丝体多糖的提取工艺优化研究

研究了茯苓菌丝体多糖的提取工艺,在单因素试验的基础上,采用响应面法对茯苓菌丝体多糖提取工艺进行了优化。试验结果表明:优化后的菌丝体多糖提取工艺条件为液料比20∶1 (mL/g)、pH 7.1、提取温度66℃,提取时间31 min。在此工艺条件下,多糖提取率为3.36%。     

杏鲍菇蛋白质提取及功能性质测定

以杏鲍菇副产物为原料,通过干燥、粉碎、碱提、酸沉、回调、冻干等工艺提取杏鲍菇蛋白质。研究了pH值、固液比、提取温度和提取时间等单因素对蛋白质提取率的影响,并经正交试验优化提取工艺条件,分析了杏鲍菇蛋白的等电点、溶解度、吸油性、吸水性、起泡性和起泡稳定性以及乳化性和乳化稳定性。结果表明:杏鲍菇蛋白质适宜提取工艺条件为pH值11.0、固液比1:40(g/mL)、提取时间40 min、杏鲍菇蛋白质提取率为(42.37±1.63)%、纯度(63.4±0.87)%。     

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press