超声辅助提取苯酚-硫酸法测定野生平盖灵芝多糖含量

测定平盖灵芝多糖含量,并与不同品种灵芝多糖含量进行对比,为其开发利用提供数据支持。采用超声辅助热水提取技术提取平盖灵芝多糖,对超声提取条件(温度,料液比,提取时间)进行系统优化,并采用苯酚-硫酸法测定平盖灵芝多糖含量。结果表明:超声辅助热水浸提结合苯酚-硫酸法测定灵芝多糖的方法效率高,最佳提取条件为:提取温度90℃,料液比1∶15(g/m L),提取时间30 min。含量测定结果表明,不同品种的灵芝多糖含量存在一定差异,平盖灵芝的多糖含量最高,为2.68%;赤芝多糖含量其次,为2.01%;黑芝和紫芝多糖含量较为接近,分别为1.62%和1.61%。平盖灵芝多糖含量较高,研究结果为平盖灵芝的开发利用提供了方法和数据支持。     

苯酚-硫酸法与蒽酮-硫酸法测定地参多糖的比较研究

苯酚-硫酸法和蒽酮-硫酸法是测定多糖含量的常用方法,运用这2种方法测定地参中多糖的含量,比较2种方法的优劣,发现苯酚-硫酸法较优,并对苯酚-硫酸法做更深入的优化试验。在单因素试验结果的基础上,选取苯酚用量、硫酸用量、加热时间3个因素进行响应面优化试验,得出最佳试验条件为苯酚用量0.8 mL、硫酸用量3.5 mL、加热时间9 min。利用该条件对地参多糖进行测定,得出地参多糖含量的平均值为14.41%,相对标准偏差为2.76%,表明苯酚-硫酸法稳定可靠,更能准确测定地参中多糖的含量。     

灵芝深层液体发酵多糖的提取与测定

阐述了灵芝深层液体发酵多糖的提取及分析方法,采用乙醇沉淀提取多糖,柱层析法纯化多糖,多糖的测定采用苯酚—硫酸法,并对测定条件进行选择,确定最佳测定条件:波长为497nm、显色温度为30℃、显色时间为20min。     

5种灵芝孢子粉多糖含量的分析对比研究

采用超声波辅助热水法提取灵芝孢子粉多糖,结粜表明该方法精密度良好,超声处理时间为25min,处理温度为70℃.多糖含量采用传统的苯酚-硫酸法榆测.实验结果表明,3号灵芝孢子粉样品中多糖含量高,并且所含灵芝多糖稳定性好.     

复方灵芝胶囊中粗多糖测定方法研究

目的建立复方灵芝胶囊中粗多糖的含量测定方法。方法将复方灵芝胶囊内容物用糖化酶酶解,醇沉法提取粗多糖,苯酚-硫酸法测定其含量,并对糖化酶用量、酶解时间条件进行了优化。结果糖化酶用量0.1 g,酶解时间60 min为优,测定粗多糖的标准曲线相关系数为0.9995,平均回收率为98.41%,RSD为3.50%。结论该方法操作简便,显色稳定、重现性及稳定性良好,适用于复方灵芝胶囊中粗多糖的含量检测。     

苯酚-硫酸法测定银杏外种皮多糖的含量

目的:建立分光光度法测定银杏外种皮多糖的方法.方法:采用苯酚-硫酸法对银杏外种皮多糖含量进行测定,在单因素实验结果的基础上,进行正交实验设计,考察苯酚用量、硫酸用量和显色温度对吸光度的影响.结果:硫酸用量是影响显色的重要因素.最佳条件为5%苯酚1.2 mL、硫酸4 mL、显色温度30℃和显色时间20 min,该方法平均回收率为99.60%,RSD=3.02%(n=5).结论:该法快速.重现性好,适用于银杏外种皮多糖的含量测定.     

苯酚-硫酸法测定南瓜籽多糖含量的条件优化

对苯酚-硫酸法测定南瓜籽多糖含量的条件进行探讨,研究在苯酚-硫酸法中吸收波长、浓硫酸用量、苯酚用量、显色温度和显色时间等因素对显色结果的影响,并对该法的精密度、加标回收率等进行研究。结果表明,优化后的测定条件为显色波长486nm、6%苯酚的用量1.0mL、浓硫酸用量5.0mL、30℃水浴30min。该条件下,平均加样回收率为100.75%,相对标准偏差(RSD)为0.83%。证明苯酚-硫酸法是测定南瓜籽多糖含量的一种稳定性好、回收率高的简便方法。     

改进苯酚-硫酸法快速测定虫草多糖含量

改进苯酚硫酸法利用全波长酶标仪测定虫草多糖的含量,并对虫草多糖测定样品的制备和测定条件进行了研究.结果表明,2 g样品在212°F条件下水浴2 h,加入25 mL无水乙醇混匀,以3 000 r/rain离心5 min即可制得合适的待测定样品.在待测样品中加入硫酸9 mL,显色1 min后,在酶标仪上用490 nm波长测定样品的吸光值.     

牛肝菌多糖的含量测定

苯酚-硫酸法是测定多糖的常用方法,影响该法显色的因素较多,对不同多糖物质,其最佳显色条件不同。采用正交试验设计法确定牛肝菌多糖的最佳显色条件。结果表明,在显色时间25m in、显色温度70℃、苯酚1.2mL、硫酸8.0mL条件下,采用苯酚-硫酸法测定牛肝菌多糖含量时,平均回收率达99.0%,RSD3.70%(n=6)。     

甘肃河西沙区锁阳多糖提取工艺优化及含量测定

采用水提醇沉法,利用L9(33)正交试验优选锁阳多糖的提取工艺,用硫酸苯酚比色法对甘肃河西沙区不同地区锁阳中多糖含量进行测定。结果表明：提取最佳工艺条件为料液比1:15(g/mL)、提取时间90min、提取次数为2次;甘肃河西沙区不同地区锁阳多糖含量差别显著。锁阳多糖可作为控制锁阳质量的一项指标性成分。     

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.