松籽壳总黄酮超声提取工艺响应面优化

为研究松籽壳总黄酮超声提取工艺,以超声波功率、乙醇体积分数、料液比、提取时间为考察因素,采用Box-Be-hnken试验设计进行工艺参数优化。结果表明,松籽壳总黄酮的最优提取工艺条件:超声波功率250W、乙醇体积分数50%、料液比1∶25(m∶V)、提取时间31min。该条件下,松籽壳总黄酮得率为15.37mg/g。     

拐枣总黄酮超声波辅助提取工艺优化

为开发利用拐枣中总黄酮资源,采用响应面法优化乙醇-超声波辅助提取拐枣中总黄酮的工艺。结果表明,拐枣总黄酮乙醇-超声波辅助提取最优工艺条件为:乙醇体积分数50%、料液比1:50(g/mL)、提取温度55 ℃、超声波功率300 W、提取时间60 min,在此条件下总黄酮提取得率为3.60%±0.03%。表明拐枣总黄酮可采用乙醇-超声波辅助提取。     

超声波辅助提取祁连圆柏叶总黄酮工艺的研究

研究超声波辅助提取祁连圆柏叶总黄酮的最佳提取工艺条件。以祁连圆柏叶为原料,考察乙醇体积分数、料液比、提取时间、超声功率对其总黄酮提取率的影响,并在此基础上采用L9(34)正交试验设计对提取工艺进行优化。结果表明,总黄酮的最佳提取工艺为:乙醇体积分数90%、料液比1︰20、提取时间40 min、超声功率105 W。     

响应面法优化超声波辅助提取湖北海棠叶中总黄酮工艺

采用超声波辅助提取湖北海棠叶中总黄酮,并利用响应面法对提取工艺参数进行优化。在料液比、乙醇体积分数、超声时间、超声功率等单因素试验基础上,进行四因素三水平的Box-Behnken设计,利用响应面法分析4个因素对湖北海棠叶中总黄酮得率的影响。超声波法提取湖北海棠叶中总黄酮的最佳工艺条件为液料比50:1(mL/g)、乙醇体积分数67.35%、超声时间3.2h、超声功率162.4W,总黄酮得率预测值为12.78%,验证值为12.76%,与理论值的相对误差为0.02%,表明该优化方法合理可行。     

万年蒿总黄酮超声波提取工艺的优化

以万年蒿为原料,研究超声波提取万年蒿总黄酮的最佳工艺。通过单因素试验研究乙醇体积分数、料液比、超声波功率及超声时间对总黄酮提取量的影响。以此为基础,采用L9(34)正交试验设计,优化超声波提取万年蒿总黄酮工艺条件;并将其与传统的热回流法和浸提法进行了比较。超声波提取万年蒿总黄酮的最佳提取工艺参数为:乙醇体积分数60%,料液比1∶20(g:mL),超声波功率350 W,超声时间60 min。在此工艺条件下,万年蒿总黄酮提取量为69.55 mg/g。     

超声波法提取紫薯茎叶中总黄酮的工艺优化

以紫薯茎叶为实验材料,采用超声波辅助溶剂法提取其中的总黄酮,考察液料比、提取时间、提取温度、超声功率和乙醇体积分数对紫薯茎叶中总黄酮得率的影响。基于单因素实验,选取四个主要影响因素液料比、超声时间、超声功率、乙醇浓度,应用Box-Behnken响应面实验设计法优化工艺条件。研究表明,紫薯茎叶中总黄酮的最佳提取工艺条件是:液料比18:1 (mL/g)、提取时间50 min、超声功率200 W、乙醇体积分数75%,总黄酮实际得率为3.46%,与预测值3.51%相接近,研究结果为总黄酮的高效提取及紫薯茎叶的综合利用提供了参考。     

响应面法优化白茅根总黄酮超声辅助提取工艺

以白茅根为原料,利用超声波辅助提取,响应面法优化白茅根总黄酮的提取工艺参数。在单因素试验基础上,选取乙醇体积分数、液料比、超声功率、提取时间为影响因素,用响应面分析法优化白茅根总黄酮的提取工艺条件。结果表明,在乙醇体积分数50%,液料比25∶1(m L/g),超声功率530 W,提取时间30 min的最佳提取工艺条件下,提取到2.18 mg/g的白茅根总黄酮,与理论预测值2.21 mg/g相近。说明采用响应面法优化白茅根总黄酮提取工艺具有可行性。     

响应面法优化超声波辅助提取文冠果种皮总皂苷的工艺

采用超声波辅助萃取法提取文冠果种皮中的总皂苷。考察了乙醇体积分数、超声波功率、料液比、提取时间和提取温度对总皂苷提取率的影响,在单因素试验的基础上选取对总皂苷提取率影响显著的料液比、乙醇体积分数和超声波功率,利用Box-Behnken设计原理,以总皂苷提取率为响应值进行响应面试验,建立了回归方程,得到了优化的提取条件(料液比1∶30,乙醇体积分数73%,超声波功率220 W)。在提取温度50℃、提取时间90 min及优化的提取条件下,文冠果种皮总皂苷提取率达0.30%。     

超声波辅助法提取假苹婆树叶总黄酮及其清除羟自由基能力

利用超声波辅助提取技术研究假苹婆树叶总黄酮的提取工艺及其抗氧化活性。以总黄酮得率为研究对象,考察了料液比,乙醇体积分数、提取功率、提取时间及提取温度对提取效果的影响,通过正交试验对提取工艺进行了优化。结果表明,最佳提取工艺条件为:乙醇体积分数为60%,提取功率为60 W,料液比为1:25(g/mL),70℃提取65 min,该条件下总黄酮得率为2.36%±0.0002%。抗氧化试验表明,假苹婆提取液对羟自由基的清除能力随着提取液中总黄酮浓度的增大而增强,当假苹婆树叶总黄酮的质量浓度为4.92 mg/mL时,清除率达到73.58%。     

超声波提取枣树皮中总黄酮的条件研究

采用超声波法提取金丝小枣枣树皮中的总黄酮。通过单因素试验研究了料液比、乙醇体积分数、提取时间、超声功率和超声温度等因素对总黄酮提取率的影响,并进行了四因素三水平正交试验,确定了枣树皮总黄酮的最佳提取条件。结果表明:最佳提取条件为料液比1∶15(g/m L),乙醇体积分数50%,提取时间50 min,超声功率342 W,提取温度70℃,提取两次。此条件下总黄酮的平均提取率为5.53%。     

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.     

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.