玉米大豆复合肽体内ACE抑制活性研究

为了考察玉米大豆复合肽的体内抑制血管紧张素转化酶(ACE)活性,采用自发性高血压鼠(SHR)为模型,进行了一次性给药和长期给药动物试验,并以卡托普利(Captopril)作为阳性对照,采用尾袖法测定SHR的血压变化.结果表明:一次性给药后,中(50 mg/kg·bw)、高剂量(100 mg/kg·bw)玉米大豆复合肽(CSP)组的降血压作用可一直持续3 h,血压值降低达显著水平(P<0.05);长期试验中,每日给予CSP,12 d后开始,与模型组SHR比较,中剂量组(25 mg/kg·bw)和高剂量组(50 mg/kg·bw)的SHR血压值均明显降低(P<0.05～P<0.01);高剂量(50 mg/kg·bw)给肽组的降血压效果略好于Captopril组,并对正常大鼠的血压无影响;CSP对大鼠有增加体重的作用.因此CSP对SHR具有良好的短期和长期降血压作用,并对正常血压大鼠无影响;CSP同时是大鼠良好的营养剂.     

大豆肽减肥降血脂作用的研究

采用大豆肽对Wistar大鼠进行实验,研究大豆肽的减肥降血脂作用。大豆肽减肥作用实验中,低剂量300 mg/kg.bw灌胃Wistar大鼠,其脂体比下降了34.85%。大豆肽降血脂作用实验中,低剂量300 mg/kg.bw灌胃Wistar大鼠,其血清总胆固醇下降了20.74%,同时其低密度脂蛋白下降了14.05%;中剂量600 mg/kg.bw灌胃Wistar大鼠,其高密度脂蛋白增加了9.03%,中剂量600 mg/kg.bw和高剂量1200 mg/kg.bw灌胃Wistar大鼠,其甘油三酯分别下降了45.10%和51.20%。研究结果表明大豆肽具有一定的减肥降血脂保健作用。     

米糠蛋白ACE抑制肽在大鼠体内降压效果的研究

采用灌胃和静脉注射的方法,观察了米糠蛋白ACE抑制肽对应激性高血压(SHR)大鼠的降压效果,并与卡托普利的降压效果进行了比较。分别以50、100、150 mg/kg·bw剂量的米糠蛋白ACE抑制肽一次性给药后,每2 h测量大鼠血压,连续测量8 h;实验持续4周,每天灌胃一次,每周测量血压及体重一次。SHR大鼠给予米糠蛋白ACE抑制肽后,血压均显著下降(p0.05),并均在灌胃后2 h达到最低值,血压下降最大幅度为(31±6.8)mm Hg;而正常大鼠灌胃米糠蛋白ACE抑制肽后血压无显著变化,灌胃卡托普利则会明显降低其血压;长期灌胃米糠蛋白ACE抑制肽可使SHR大鼠血压下降明显(p0.05),且降压效果稳定。     

玉米低聚肽降血压作用的实验研究

为了研究玉米低聚肽的降血压作用,以原发性高血压大鼠为实验动物,分别灌胃给予不同剂量(0.45、1.35、4.05g/kg.bw)的玉米低聚肽,空白对照组灌胃给予相应剂量的蒸馏水,阳性对照组灌胃给予10mg/kg.bw卡托普利。连续灌胃8周后,各组大鼠体重、心脏/体重比、心率无明显变化(P>0.05)。低、中剂量组和卡托普利组的收缩压均显著低于空白对照组(P<0.05),低剂量组与卡托普利组的降压效果相当。高剂量组和卡托普利组的血清醛固酮浓度显著低于空白对照组(P<0.01)。实验结果表明,玉米低聚肽具有明显的降血压作用,这一结果将为进一步开发降血压药物和功能食品提供了科学依据。     

玉米肽对半乳糖胺诱导肝损伤小鼠的保护作用

为了研究玉米肽对D-半乳糖胺(D-Gal)诱导小鼠化学性肝损伤的保护作用,将小鼠随机分成五组,即空白组、模型组和三个玉米肽(CP)组,每天灌胃一次,CP组灌胃玉米肽剂量分别为160、320、640 mg/kg·bw,空白组和模型组则灌胃等量生理盐水,10 d后模型组和CP组腹腔注射D-Gal(750 mg/kg·bw),诱导小鼠肝损伤.通过试剂盒的方法分别检测各组小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)活力,及谷胱甘肽(GSH)、甘油三酯(TG)含量;并进行肝组织病理学镜检.结果显示,与模型组比,以640mg/kg. bw剂量给予玉米肽,可极显著降低小鼠血清ALT、AST的活性和TG含量,提高血清中GSH的含量(P<0.01),且肝组织病理学镜检结果显示已接近正常组;CP组生化指标及肝组织病理学变化存在明显的剂量——效应关系.玉米肽对D-Gal诱导的小鼠肝损伤有很好的保护作用.     

双酶法制备玉米肽及其对D-半乳糖胺致肝损伤小鼠的保护作用

目的：研究双酶法制备的玉米肽(CCP)对D-半乳糖胺(D-GalN)诱导小鼠化学性肝损伤的保护作用。方法：将60只小鼠随机分成正常对照组、模型组、联苯双酯阳性对照组、玉米肽低、中、高剂量组,每天灌胃一次,阳性对照组灌胃联苯双酯 200mg/kg bw,玉米肽组分别灌胃CCP180、360、720mg/kg bw,正常组、模型组灌胃等量生理盐水。10d后,除正常组外,其余各组小鼠均腹腔注射D-Gal(700mg/kg bw),诱导小鼠肝损伤。通过试剂盒的方法分别检测各组小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)活力,肝组织中丙二醛(MDA)、谷胱甘肽(GSH)含量及超氧化物歧化酶(SOD)活力;并进行肝组织病理学镜检。结果：与模型组比,以720mg/kg bw剂量给予CCP,可极显著降低小鼠血清ALT、AST的活性和肝组织中MDA含量(p＜0.01),并可显著提高肝组织中SOD的活力和GSH的含量(p＜0.05～0.01),其保肝效果与200mg/kg bw联苯双酯接近;肝组织病理学镜检结果显示已接近于正常组。结论：双酶法制得的玉米肽对D-GalN诱导的小鼠肝损伤有良好的保护作用。     

玉米肽对免疫性肝损伤小鼠的保护作用

研究了玉米肽(CCP)对卡介苗与脂多糖(BCG+LPS)诱导的小鼠免疫性肝损伤的保护作用.将60只小鼠随机分成正常组、模型组、水飞蓟宾阳性对照组、CCP低、中、高剂量组,第1 d,除正常组外,其余各组均经尾静脉注射BCG致敏;玉米肽组分别灌胃CCP 150、300、600 mb/kg·bw,阳性对照组灌胃水飞蓟宾50 mg/kg·bw,正常组、模型组则给予等量生理盐水,每天灌胃一次.15 d后,除正常组外,其余各组经尾静脉注射LPS攻击,诱导小鼠肝损伤.用试剂盒的方法分别检测各组小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)活力,肝组织中丙二醛(MDA)、谷胱甘肽(GSH)、NO含量及超氧化物歧化酶(SOD)与谷胱甘肽过氧化物酶(GSH-Px)的活力;并进行肝组织病理学镜检.结果与模型组相比,CCP高剂量组可极显著降低血清中ALT、AST活性(P<0.01),提高肝组织中GSH含量和SOD、GSH-Px活力,并降低肝组织中MDA、NO的含量(P<0.01),其护肝效果与50 mg/kg·bw水飞蓟宾接近;肝组织病理学镜检结果显示接近于正常组.玉米肽对卡介苗与脂多糖(BCG+LPS)诱导的小鼠免疫性肝损伤有良好的保护作用.     

海苔发酵提取物对原发性高血压大鼠的降压效果研究

使用可以产生GABA的植物性乳酸菌对海苔进行发酵,得到富含10.5%GABA的海苔发酵提取物。本实验验证了海苔发酵提取物对原发性高血压模型大鼠(SHR)的降压效果。单次经口灌胃给药实验中,分别以2mg/kg·bw和0.2mg/kg·bw剂量的海苔发酵提取物一次性灌胃给药,给药后2、5、9、24h进行血压测定。结果表明,海苔发酵提取物2mg/kg·bw剂量组在给药后5h和24h均有显著降压效果(p<0.05,p<0.01)。长期摄食给药实验中,含有海苔发酵提取物0.001%和0.003%的饲料剂量组对成长期SHR和老龄期SHR分别摄食给药,给药后每2～3d进行一次血压和体重测量,结果显示含有海苔发酵提取物0.003%的饲料剂量组使成长期SHR和老龄期SHR血压均显著下降(p<0.01,p<0.05)。     

灵芝肽对乙醇诱导肝损伤小鼠的保护作用

目的：研究灵芝肽(GLP)对乙醇诱导的肝损伤小鼠的保护作用。方法：将60 只小鼠随机分成6 组,每组10 只,分别为正常组,乙醇肝损伤模型组,硫普罗宁(Tiopronin)阳性对照组,GLP 低、中和高剂量组。每天灌胃一次,GLP 低、中、高剂量组分别灌胃GLP 60、120、180mg/kg bw,阳性对照组灌胃硫普罗宁溶液50mg/kg bw,正常组、模型组灌胃等量生理盐水;每次给药3h 后,除正常组外,各组均灌胃50% 乙醇16mL/kg bw,连续灌胃2 周,建立小鼠酒精性肝损伤模型。通过脏器质量和体质量计算肝、脾脏指数;按照试剂盒的方法测定小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)、甘油三酯(TG)含量,肝匀浆中超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量、还原性谷胱甘肽(GSH)含量等指标。结果：60mg/kg bw GLP 能极显著降低酒精性肝损伤所引起的ALT、AST 活性和MDA、TG 含量的升高(P ＜ 0.01),有效地拮抗肝脏中SOD的活性与GSH含量的降低(P ＜ 0.05～0.01)。结论：60mg/kg bw GLP 对乙醇诱导的肝损伤小鼠有显著的保护作用,180mg/kg bw GLP 的保肝效果好于50mg/kg bw硫普罗宁。     

α-酪蛋白源ACE抑制肽对高血压大鼠血压的影响

研究水解α- 酪蛋白所得水解产物对原发性高血压大鼠(SHR)血压的影响。用α- 酪蛋白水解产物以低、中、高3 个剂量(0.0245、0.1225、0.6125g/kg bw)分别灌胃SHR 大鼠,0.6125g/kg bw 灌胃正常Wistar 大鼠,测定灌胃后1～8h 尾动脉收缩压(SBP)。结果显示,单次灌胃8h 内,高剂量α - 酪蛋白水解产物对正常Wistar 大鼠的血压无影响;3 种剂量对SHR的血压升高有明显抑制作用,且高剂量组在0～6h 内降压效果最佳,SBP 维持在较低水平的时间最长,达到6h,SBP 值下降了(29.50 ± 1.0)mmHg。连续灌胃高剂量α- 酪蛋白水解产物可较长时间维持低水平SBP。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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