宾川葡萄籽原花青素纯化及对HepG2细胞增殖的影响

目的:研究云南大理宾川葡萄籽原花青素纯化及对肝癌HepG2细胞增殖的影响。方法:考察了上样液质量浓度、pH、流速、乙醇体积分数等对葡萄籽原花青素吸附及解析的影响,研究AB-8型大孔吸附树脂纯化云南大理宾川葡萄籽原花青素的条件。将纯化过程中乙醇梯度洗脱得到的不同极性葡萄籽原花青素作用于HepG2细胞,采用CCK8法检测不同浓度各极性葡萄籽原花青素对肝癌HepG2细胞增殖的影响。结果:AB-8树脂纯化葡萄籽原花青素的最佳工艺为上样液pH4.0,质量浓度为6.0 mg/mL,流速为1.0 BV/h,洗脱液的体积分数为30%,洗脱体积4 BV。此纯化使葡萄籽提取物中原花青素的含量从22.77%±0.32%提高至94.73%±0.6429%,回收率为80.55%±1.6499%。以10%、20%、30%、40%乙醇洗脱的葡萄籽原花青素极性部位各浓度对肝癌HepG2细胞的增殖均有抑制作用,其中未纯化部位（即提取物未经过大孔树脂纯化）给药浓度为200 μg/mL时抑制作用最为显著（P<0.001）,10%乙醇组IC₅₀为25.09 μg/mL,抑制效果良好。结论:云南大理宾川葡萄籽原花青素用AB-8型大孔树脂进行纯化,方法可行,该葡萄籽原花青素对肝癌HepG2细胞的增殖有较好抑制作用。     

葡萄籽原花青素的分离纯化及其抗氧化活性研究

本文以脱脂葡萄籽为原料从中提取原花青素,研究用大孔吸附树脂对原花青素分级纯化方法,以及纯化的原花青素产品清除超氧阴离子自由基、亚油酸体系的抗氧化等方面的抗氧化活性。结果显示:ADS-8大孔树脂对葡萄籽原花青素具有较强的吸附能力,得到的产物纯度达95%以上,是分离葡萄籽原花青素较理想的吸附剂;20%和40%的乙醇原花青素洗脱液具有很强的清除O2-·的能力,抑制邻苯三酚自氧化率分别达88.35%和67.2%,说明葡萄籽原花青素为抗自由基的有效活性成分;在亚油酸体系中,OPC’s的抗氧化能力高于VC和VE。     

鸡血藤原花青素的纯化及活性评价

采用大孔吸附树脂对鸡血藤原花青素进行纯化,并对原花青素纯度、1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除活性及α-葡萄糖苷酶抑制活性进行评价。比较3 种大孔吸附树脂对原花青素静态吸附及解吸附能力,从D101、X-5及AB-8树脂筛选出X-5型树脂用于纯化。对X-5型树脂的动态吸附及解吸附条件进行优化,获得最适条件为：上样质量浓度6.00 mg/mL,上样流速2 BV/h,上样量10 BV,洗脱流速1 BV/h,洗脱剂用量2 BV。利用不同体积分数乙醇洗脱可得到不同纯度的原花青素,其中70%乙醇纯化物原花青素纯度最高,具有最强的DPPH自由基清除活性及α-葡萄糖苷酶抑制活性。相关性分析表明原花青素可能是鸡血藤抗氧化及抑制α-葡萄糖苷酶的主要活性成分。     

三叶青原花青素纯化工艺及抗氧化、α-葡萄糖苷酶抑制活性研究

为了探索三叶青中原花青素的纯化工艺及其生物活性作用,制备经济高效的原花青素,比较5种大孔吸附树脂对三叶青原花青素静态吸附及解吸附能力,并对树脂的动态吸附及解吸附条件进行优化。同时,探讨乙醇洗脱对原花青素纯度及生物活性影响。结果表明,AB-8型树脂可用于三叶青中原花青素纯化,纯化三叶青原花青素的最适条件为:上样质量浓度6.00 mg/mL,上样流速2 BV/h,上样体积11 BV,洗脱流速1.5 BV/h,洗脱剂用量2 BV,70%乙醇吸附效果最好,纯化后的三叶青原花青素纯度达到97.31%±0.96%,比粗提物提高了2.2倍,1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除活性、ABTS+自由基清除活性及α-葡萄糖苷酶抑制活性得到了显著增强（P<0.05）,并且与原花青素含量之间存在极显著相关性（P<0.01）。因此,AB-8树脂纯化法简单、高效,且三叶青原花青素具有较强的体外抗氧化活性以及α-葡萄糖苷酶抑制活性,为综合开发利用三叶青原花青素提供科学参考。     

聚酰胺柱层析提纯原花青素及其产物清除·OH自由基能力的研究

研究了聚酰胺柱层析技术吸附分离葡萄籽原花青素的效果,并对比了分级洗脱产物的清除羟自由基的能力。结果表明,聚酰胺吸附分离原花青素的适宜上样流速为0.45ml/min,上样浓度为5～8mg/ml。用80%丙酮溶液洗脱时,可获得最高的产率。在分级洗脱物中,80%和40%丙酮洗脱物的清除·OH能力最强,其次是60%浓度的丙酮洗脱液,各产物的抗氧化性均好于儿茶素。     

葡萄籽原花青素的提取与分离

原花青素是葡萄籽中含有的一种重要的生理活性物质。采用溶剂浸提的方法从葡萄籽中提取原花青素,并通过单因素试验和正交试验优化了最佳提取工艺参数为:乙醇浓度70%,浸提时间120m in,料液比1∶20,浸提温度40℃。选取四种不同的大孔树脂(DA201、AB-8、HPD-100、HPD-700)对最佳条件下提取的粗提液进行静态吸附、解吸实验和动态实验,结果表明:DA201为吸附葡萄籽原花青素的最佳树脂;当原花青素浓度为0.15mg/mL时,上样流速为1mL/m in,洗脱流速为1mL/m in,洗脱剂乙醇浓度为70%,用量为5BV时的纯化效果最佳。     

大孔树脂串联吸附原花青素和茶皂素的工艺研究

采用大孔树脂分级串联的方法吸附茶壳提取液中的原花青素和茶皂素,经试验得到最佳工艺条件:将茶壳提取液经过DM–130大孔树脂进行1级吸附,调节上柱液中茶皂素的浓度为1.5 mg/m L,pH为6,吸附流速为1.5 BV/h,吸附完毕后采用50%乙醇进行洗脱,洗脱液浓缩干燥后得到纯度为85.6%的茶皂素产品。收集流出液并经S–8树脂进行2级吸附,调节上柱液中原花青素的浓度为1 mg/m L,pH为4,吸附流速为2 BV/h,吸附完毕后采用30%乙醇进行洗脱,洗脱液浓缩干燥后得到纯度为73.7%的原花青素产品。     

AB-8树脂对葡萄籽原花青素按聚合度分离特性的研究

AB-8树脂对葡萄籽原花青素具有吸附量大、解吸率高、选择性好等特点,适于分离并得到纯度较高的葡萄籽原花青素。对其分级分离特性的研究表明,采用AB-8树脂吸附分离原花青素,通过逐步提高乙醇浓度(10%～50%)可以将原花青素按聚合度由低到高的顺序依次洗脱下来,从低浓度乙醇洗脱液中可以得到低聚体含量相对较高的原花青素组分,并且可用于原花青素的工业化生产。     

大孔树脂分离纯化芦苇叶总黄酮

研究5种大孔树脂纯化芦苇叶总黄酮的性能及工艺.结果表明:AB-8树脂对水提及醇提芦苇叶总黄酮皆有良好的吸附及解吸性能,当两种提取液上样液浓度分别为0.80mg/mL、1.12mg/mL,pH值皆为4,上样流速皆4 BV/h时吸附效果最好;洗脱液分别为60%和70%乙醇,洗脱液用量皆为3倍树脂柱体积,洗脱流速皆为2BV/h时,洗脱效果最好.     

大孔树脂纯化胭脂萝卜花青素及抗氧化活性研究

以重庆市特色蔬菜胭脂萝卜为原材料提取花青素,以吸附率和解析率为指标考察6种大孔树脂对胭脂萝卜花青素的纯化效果,从中筛选出最佳大孔树脂并探讨其吸附性能和纯化工艺,分析最佳树脂纯化前后胭脂萝卜花青素的色价及抗氧化活性。结果表明,AB-8树脂在吸附和解析3h后其吸附率和解析率达到91.2%和96.6%。AB-8树脂的纯化工艺为:上样浓度为0.80 mg/mL,上样液pH 4,上样流速8 mL/min,洗脱流速6 mL/min。经AB-8树脂纯化后的胭脂萝卜花青素色价是粗提液的9倍。0.75mg/mL的胭脂萝卜花青素纯化液抗氧化活性显著高于同浓度的花青素粗提液及维生素C,经AB-8树脂纯化的胭脂萝卜花青素纯化液对羟自由基、DPPH自由基及油脂的清除能力显著提高。以上结果表明,AB-8树脂是胭脂萝卜花青素的最佳纯化树脂。     

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