大孔树脂法精制栀子红色素

采用大孔树脂法对栀子红发酵液进行了精制.结果表明,大孔树脂GDX-201对栀子红色素具有良好的吸附效果,其精制过程为,栀子红发酵液经离心后,上清液上柱至吸附饱和,先用15%乙醇冲洗去杂,再用含0.5%Na2CO3的55%乙醇洗脱,回收洗脱液经浓缩干燥后,得到栀子红粉末,得率为88.55%,色价可达到95.67(E1%1cm,532nm),比精制前提高了近10倍.     

栀子黄色素标准品藏红花素的制备

用栀子果实为原料,采用大孔吸附树脂法联合硅胶层析法精制栀子黄色素的标准品藏红花素。其栀子黄色素树脂精制条件:吸附条件为树脂30 mL,栀子黄色素提取液上样量300 mL;吸附流速1.5 mL/min;洗脱条件为提取液杂质洗脱乙醇体积分数30%,洗脱体积150 mL;栀子黄色素洗脱乙醇体积分数50%,洗脱体积150 mL;在此条件下可制得色价≥300,OD值0.4的桅子黄色素,并用其硅胶层析精制藏红花素。硅胶柱层析条件,洗脱流动相:V(乙酸乙酯)∶V(甲醇)∶V(水)=10∶2∶1;V(乙酸乙酯)∶V(甲醇)∶V(水)=10∶3∶1,进行梯度洗脱制取藏红花素。栀子黄色素提取液经过分离纯化,红外光谱、质谱测定,确定为藏红花素的结构,经高效液相色谱检测,藏红花素的纯度达98%。     

大孔吸附树脂纯化栀子蓝色素的工艺研究

探讨大孔吸附树脂对栀子苷发酵液的纯化条件。以栀子蓝色素色价和含量为指标,比较了多种大孔吸附树脂对栀子蓝色素的静态吸附和洗脱效果,筛选出效果较好的D4020树脂进行动态吸附洗脱试验,对栀子蓝色素的纯化工艺进行优选。结果表明:纯化的最终条件为,上样时栀子苷发酵液A590nm为0.71,吸附流速1.5mL/min,树脂的饱和吸附量为6.5BV,用2BV的60%乙醇即可洗脱栀子蓝色素。精制的栀子蓝色素色价为130.82,得率为64.47%。     

中等纯度栀子苷的纯化和制备工艺研究

以树脂法分离富集栀子黄色素后的栀子苷粗提液为研究对象,探讨两步吸附树脂法分离纯化栀子苷的制备工艺。考察栀子苷在12种大孔吸附树脂中的静态吸附和解吸性能,并采用吸附动力学模型和颗粒内扩散模型对吸附过程进行预测性拟合。在此基础上选择非极性树脂X-5研究栀子苷的动态纯化,探索不同pH和不同浓度洗脱剂对栀子苷纯化的影响。结果表明:一级吸附动力学Lagergren方程能很好地拟合栀子苷的吸附过程,颗粒扩散是影响栀子苷吸附效果的主要作用因素,饱和吸附量为8.2mg/g(栀子苷/X-5树脂),进一步精制的优化条件为pH 5.5,20%乙醇洗脱。经3次重复性扩大验证实验,洗脱产物中栀子苷纯度可达65.4%,回收率92.3%。大孔树脂分离纯化栀子苷的优化工艺对规模化制备中等纯度的栀子苷及重结晶单体生产提供了科学基础和实验依据。     

栀子中熊果酸提取分离及纯化研究

建立一种栀子中熊果酸提取分离及精制的方法;采用超声提取法,研究提取次数、提取时间、超声功率和提取溶剂4个因素,并用正交法进行优化,将得到的提取物用大孔树脂进行精制,研究了精制工艺;栀子最佳提取工艺条件为浸提2次,每次60 min,超声功率为500 W,浸提溶剂为80%乙醇溶液。筛选出AB-8大孔树脂用于吸附分离熊果酸,其工艺为上柱浓度30 mg/mL,上柱流速为2 BV/h,洗脱流速2 BV/h,采用40%~90%乙醇溶液作为洗脱剂,得到熊果酸纯度在80%以上,且产率达到60%以上。     

高色价栀子蓝色素的制备及其纯化工艺研究

以栀子黄废液中的栀子苷为原料,采用酶促反应制得栀子蓝色素,并利用壳聚糖衍生物作为层析柱填料对其进行精制纯化.通过正交实验确定了最佳的酶促反应工艺条件为:浓度为40%的栀子苷溶液100mL,反应温度50℃,反应时间50h,β-葡萄糖苷酶3mL,甘氨酸10g.层析法精制纯化的工艺务件为:层析柱径长比是1:20,上样量/填料比为1:40,蒸馏水作为洗脱剂,洗脱速度为0.1mL/s.精制得到的栀子蓝色素粉末的色价(E1cm 1%)为238,OD值为0.24,达到了国际市场标准.     

栀子黄色素的提取及精制研究

本文通过正交试验,确定了超声波法提取栀子黄色素的最佳工艺条件为:乙醇溶液60%、温度为45℃、提取时间20min。同时,本文对几种大孔树脂对栀子黄色素的精制条件和效果进行了研究。结果表明:D3520、D140树脂的精制效果较好,适合制备高色价的栀子黄色素。经D140树脂精制后的栀子黄色素的色价达到401,得率为1.80%;经D3520树脂精制后的栀子黄色素的色价达到434,得率为1.33%。二者比较,D3520精制的栀子黄色素的色价略高,OD比值略低,而D140树脂的吸附容量更大。     

栀子黄色素的提取及精制研究

通过正交试验,确定了超声波法提取栀子黄色素的最佳工艺条件为:乙醇溶液60%、温度为45 ℃、提取时间20 min.同时,对几种大孔树脂对栀子黄色素的精制条件和效果进行了研究.结果表明:D3520、D140树脂的精制效果较好,适合制备高色价的栀子黄色素.经D140树脂精制后的栀子黄色素的色价达到401,得率为1.80%;经D3520树脂精制后的栀子黄色素的色价达到434,得率为1.33%.二者比较,D3520精制的栀子黄色素的色价略高,OD比值略低,而D140树脂的吸附容量更大.     

HPD-400大孔吸附树脂分离纯化栀子黄色素的研究

文章研究了吸附树脂法精制栀子黄色素的工艺条件.实验结果表明:大孔树脂HPD-400比较适合吸附和分离栀子黄色素,其吸附率为96.88％,pH对吸附率的影响不大,在25℃温度条件下,以适宜的乙醇浓度和速度洗脱,得到的栀子黄色素色价＞400,OD值＜0.4.     

凝胶层析法精制栀子黄色素的研究

研究了凝胶层析法精制栀子黄色素的工艺条件。其较佳的工艺条件是 :以葡聚糖凝胶为支持剂 ,双柱串联层析 (联洗 ) ,单柱高 30cm ,柱径 2cm ,洗脱流速 4mL/min ,以蒸馏水为洗脱剂 ,加样量 1 8mL ,精制得率 4 8 9%     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

Focus on China's Paper Industry

In the English section of this issue, 〈China Paper Newsletters〉 will introduce ＂National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the ＇13th Five-Year Plan＇＂, ＂2013 Annual Report of China＇s Paper Industry＂, and news of projects and other policies.     

Listen to downstream & search for innovation

正Nowadays,textile enterprises are all taking efforts in transformation and upgrading,like improving producing capacity and optimizing production structure to face market downturn.It claimed a higher request to the standard of textile equipments.In the upcoming of ITMA ASIA+CITME 2014exhibition,this magazine have interviewed several branch associations and a series of relative enterprises,to summarize industrial developing status