显齿蛇葡萄叶对食品防腐作用的研究

为了研究显齿蛇葡萄对食品的防腐效果,分别采摘3、7、11月份的显齿蛇葡萄叶作为实验材料,以大肠杆菌、金黄色葡萄球菌、苏云金芽胞杆菌、藤黄八叠球菌和枯草芽胞杆菌五种微生物为实验菌株,用药敏纸片扩散法测定不同生长时期的显齿蛇葡萄叶抑菌圈直径,通过二倍稀释法测定MBC值,以平板菌落计数反映添加有不同提取物浓度的食品中微生物的生长状况。结果表明7月份采摘的显齿蛇葡萄提取物对金黄色葡萄球菌抑菌作用最强,抑菌圈直径达到27.0mm,MBC为5%;当提取物浓度为4MBC时,肉汤食品抑菌时间延长达140h。显齿蛇葡萄有广谱抑菌作用,并且对猪肉、牛奶、西瓜和豆浆都有防腐作用。     

显齿蛇葡萄中总黄酮的测定

目的研究显齿蛇葡萄总黄酮含量测定的最佳提取条件。方法以显齿蛇葡萄为原料,用乙醇-水为溶剂,加热超声浸提,并通过试验优化出最佳的提取工艺条件,以芦丁为标准品,选择波长415 nm,采用三氯化铝分光光度法进行总黄酮含量的测定。结果在提取温度60℃、提取时间30 min、乙醇浓度95%、提取次数3次时,黄酮的提取效率最高;在此方法下,标液浓度在0.5～56μg/mL范围内,浓度与吸光值呈良好线性关系,回归方程为Y=0.0287X,r~2=0.9998,方法最低检出限为2 mg/kg,样品加标的平均回收率为98.30%,标准偏差(relative standard deviation,RSD)分别为0.94%、1.62%;通过实验室间结果比对,检测结果稳定,RSD均2.0%。结论该方法精密度及稳定性好,可以较好地提取显齿蛇葡萄中的总黄酮。     

绿凤藤茶成分分析

目的：为合理开发利用药食两用植物显齿蛇葡萄提供依据。方法：将绿凤显齿蛇葡萄、显齿蛇葡萄（绿叶）、显齿蛇葡萄（红叶）按方差分析要求种植在相同的生态环境中给予相同的田间管理，同时播种和收获干全草进行成分分析。结果：绿凤显齿蛇葡萄所含总黄酮、总氨基酸、维生素E分别高于显齿蛇葡萄（绿叶）36.3%、32.5%、49.9%，分别高于显齿蛇葡萄（红叶）30.7%、23.5%、85.6%，均达到极显著水平；总糖分别低于显齿蛇葡萄（绿叶）、显齿蛇葡萄（红叶）2.2%、10.2%。结论：绿凤显齿蛇葡萄不仅各有风味，适口性好，而且有效成分含量更高，应用领域更宽，市场需求量更大，医疗保健效果更好，更具有工业开发价值。     

显齿蛇葡萄中黄酮类化合物对α-葡萄糖苷酶的抑制作用研究

目的:研究显齿蛇葡萄醇提物及8种主要黄酮化合物对α-葡萄糖苷酶的抑制作用。方法:用75%无水乙醇回流提取制备显齿蛇葡萄提取物,对其进行α-葡萄糖苷酶抑制实验。之后选取显齿蛇葡萄中8种主要黄酮化合物对α-葡萄糖苷酶的抑制效果进行分析。结果:醇提物在(0.1~1.0)mg/mL之间对α-葡萄糖苷酶具有明显的抑制作用,其半抑制浓度(IC50)为0.338mg/mL。8种黄酮化合物均对α-葡萄糖苷酶产生不同程度的抑制作用,其中槲皮素的抑制效果最强,半抑制浓度为0.083 mg/mL,是醇提物的1/4。结论:显齿蛇葡萄醇提物与主要黄酮化合物对α-葡萄糖苷酶具有较明显的抑制作用,为显齿蛇葡萄进一步开发与利用提供了理论基础。     

显齿蛇葡萄叶总黄酮对原发性高血压大鼠的降血压研究

为了探讨显齿蛇葡萄叶总黄酮对原发性高血压大鼠的影响,采用超声波辅助提取,D-101大孔树脂纯化制备显齿蛇葡萄叶总黄酮,将SHR大鼠40只随机分成正常组、模型组、显齿蛇葡萄叶黄酮组(100、200和400 mg/kg)和依那普利组(5 mg/kg),显齿蛇葡萄叶黄酮组和依那普利组按照体重分别给予对应药物灌胃10周,分别在10周和12周测定血压及血清中各项指标。同时利用显齿蛇葡萄叶黄酮不同剂量喂养正常大鼠6个月,测定血压及血清各项指标。结果显示,显齿蛇葡萄叶黄酮治疗原发性高血压大鼠10周后能明显降低血压,另外也降低血清中血浆肾素、血管紧张素Ⅱ、内皮缩血管肽和丙二醛的含量和提高一氧化氮、超氧化物歧化酶、过氧化氢酶、谷胱甘肽的含量,对正常Wistar大鼠喂养后发现对血压基本没有影响。提示显齿蛇葡萄叶黄酮对原发性高血压大鼠具有明显的降血压效果,潜在的机理可能与肾素-血管紧张素的-醛固酮系统(RAAS)调制和抗氧化系统有关,另外显齿蛇葡萄叶黄酮对正常大鼠的血压没有影响,表明显齿蛇葡萄叶黄酮可用来作为天然药物或功能食品来预防高血压。     

显齿蛇葡萄叶有效成分的提取工艺研究

正显齿蛇葡萄为葡萄科蛇葡萄属的一种野生木质落叶藤本植物,又名白茶、藤茶、龙须茶、甘露茶等。2013年12月24日国家卫生计生委发布了《关于批准显齿蛇葡萄叶等3种新食品原料的公告》,确定了显齿蛇葡萄叶可以作为新资源食品来使用。显齿蛇葡萄叶中黄酮化合物含量高达43.4~45.5%,富含二氢杨梅素、槲皮素、显齿蛇葡萄素、山奈酚等成分。由于人体不能直接合成黄酮化合物,只能从食品中间接获得,因此研究植物中黄酮化合物的提取方     

显齿蛇葡萄生化成分分析

分析了显齿蛇葡萄春、夏、秋幼叶、幼茎及春、夏幼嫩茎叶加工样中水浸出物、水溶性糖、水溶性蛋白质、氨基酸总量、多酚类物质总量、黄酮类物质总量、总灰分等。结果表明:显齿蛇葡萄春、夏幼嫩茎叶的水浸出物含量高(近50%),其中水溶性糖含量约为10%,氨基酸含量约为5%,具有丰富药理功能的多酚类化合物含量约为20%,黄酮类化合物含量在30%以上,其黄酮类化合物含量之高在植物界中十分罕见。由此说明显齿蛇葡萄可作为一种集营养、保健和药用功能为一体的资源加以开发利用。     

荧光分析法测定显齿蛇葡萄中总黄酮的含量

根据黄酮类化合物的荧光性质,以芦丁为标样,本文采用荧光光度法测定显齿蛇葡萄中总黄酮的含量,系统研究了溶剂、pH值、表面活性剂及放置时间对荧光强度的影响。结果表明:在95%的乙醇中加入pH=2的缓冲液芦丁荧光强度最大。本方法的检测限为2.07×10-9mol/L,线性回归方程y=1.775x-0.5372,相关系数(R)0.9971,荧光强度与浓度的线性范围在1.64×10-9~4.95×10-5mol/L-,相对标准偏差为1.62%。     

显齿蛇葡萄及提取物在食品中的应用

正显齿蛇葡萄为葡萄科葡萄属的类茶植物,又名白茶、藤茶、甘露茶等,分布于湖南、湖北、云南、广东、广西等地,是中国特有植物,民间将其幼嫩茎叶代茶饮,具有清热解毒、消炎镇痛、祛风湿强筋骨等功效,是《本草纲目》遗漏的珍品。显齿蛇葡萄的营养成分中国预防医学科学院营养与食品卫生所营养成分分析显示:显齿蛇葡萄富含蛋白质、膳食纤维、维生素、脂肪、胡萝卜素,常量元素钾、钠、钙、镁、磷和微量元素铁、锌、锰、硒、碘等。其嫩叶中黄酮含量高达45.52%,号称黄酮王,其中二氢杨梅素在嫩茎叶中的含量最高可达38.5%。显齿蛇葡萄在食品中的应用2013年12月24日,国家卫生计生委发布了《关于批准显齿蛇葡萄叶     

关于批准显齿蛇葡萄叶等3种新食品原料的公告(2013年第10号)

<正>根据《中华人民共和国食品安全法》和《新食品原料安全性审查管理办法》有关规定,现批准显齿蛇葡萄叶、磷虾油、马克斯克鲁维酵母为新食品原料。生产经营上述食品应当符合有关法律、法规、标准规定。特此公告。附件:显齿蛇葡萄叶等3种新食品原料国家卫生计生委2013年12月24日附件显齿蛇葡萄叶等3种新食品原料     

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.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.