富硒大豆低聚肽的抗氧化活性研究

研究了富硒大豆低聚肽在抗氧化方面的作用。将3周龄SD雄性大鼠90只,随机分为6组,即Ⅰ(对照组)、Ⅱ(大豆蛋白组)、Ⅲ(大豆多肽组)、Ⅳ(亚硒酸钠组)、Ⅴ(大豆低聚肽组)、Ⅵ(富硒大豆低聚肽组),在实验环境下,对各组饲喂低硒基础饲料的同时,对第Ⅱ组口腔灌喂大豆蛋白,对第Ⅲ组口腔灌喂大豆多肽,对第Ⅳ组口腔灌喂亚硒酸钠,对第Ⅴ组口腔灌喂大豆低聚肽,对第Ⅵ组口腔灌喂富硒大豆低聚肽,第Ⅰ组口腔灌喂同体积的饮用水。饲喂4周,处死后分别测定各实验大鼠血清和肝脏中的MDA(丙二醛)含量、GSH-Px和SOD活性。结果显示:第Ⅱ、Ⅲ、Ⅴ、Ⅳ、Ⅵ组均能降低血清和肝脏中MDA的含量,提高GSH-Px和SOD活性,但第Ⅱ、Ⅲ组作用不显著,第Ⅴ组作用显著,第Ⅳ、Ⅵ组作用极显著。各组样品对血清和肝脏中MDA含量和GSH-Px活性的影响效果趋于一致,但对血清SOD活性的影响明显强于对肝脏SOD活性的影响,实验结果说明富硒大豆低聚肽具有抗氧化功能,这种功能主要通过降低大鼠血清和肝脏中MDA的含量,提高GSH-Px和SOD活性来实现,富硒大豆低聚肽的抗氧化功能要强于无机硒,明显强于不含硒的大豆低聚肽,推测富硒大豆低聚肽中发挥抗氧化功能的主要是微量元素硒。     

玉竹糖蛋白体内抗氧化作用研究

目的研究玉竹糖蛋白粗提物的体内抗氧化作用。方法用石油醚提取玉竹糖蛋白,以高、中、低剂量饲喂小鼠,用试剂盒测定小鼠血清、肝脏、脑组织中的丙二醛(MDA)含量、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)的活性。结果玉竹糖蛋白粗提物可提高受试小鼠血清、肝脏和脑中SOD、CAT及GSH-Px活性,降低这些组织中MDA含量。结论玉竹糖蛋白粗提物具有一定的抗氧化活性。     

玉竹糖蛋白体内抗氧化作用研究

目的 研究玉竹糖蛋白粗提物的体内抗氧化作用.方法 用石油醚提取玉竹糖蛋白,以高、中、低剂量饲喂小鼠,用试剂盒测定小鼠血清、肝脏、脑组织中的丙二醛(MDA)含量、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)的活性.结果 玉竹糖蛋白粗提物可提高受试小鼠血清、肝脏和脑中SOD、CAT及GSH-Px活性,降低这些组织中MDA含量.结论 玉竹糖蛋白粗提物具有一定的抗氧化活性.     

蝇蛆肽对衰老小鼠的作用及机制的初探

目的:探讨蝇蛆肽对衰老小鼠的作用及其机制。方法:将60只小鼠随机分为6组,除空白组外,其余五组用D-半乳糖致衰老,分为衰老模型组、维生素C组以及蝇蛆肽低、中、高剂量组(2、4、8 g/kg)。测定小鼠的脾脏和胸腺指数。采用羟胺法测定小鼠肝脏和脑及血清中的超氧化物歧化酶(SOD)活力,可见光法测定过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)的活力,以硫代巴比妥酸(TBA)法测定丙二醛(MDA)的含量。结果:与空白组相比,模型组小鼠脾指数、胸腺指数及肝脏指数均有显著降低(p0.05),蝇蛆肽低、中、高剂量组脏器指数显著增高(p0.05)。与空白组比较,模型组肝、脑中SOD、CAT、GSH-Px均降低,且MDA含量增高(p0.05),血清中SOD、CAT降低、MDA含量增高(p0.05);与模型组比较,蝇蛆肽低、中、高剂量组肝、脑组织中SOD、CAT、GSH-Px均显著增高、MDA含量显著降低(p0.05),血清中SOD、CAT显著增高、MDA含量显著降低(p0.05)。结论:蝇蛆肽通过改变衰老小鼠的脏器指数而对其产生免疫调节作用,可显著提高小鼠肝脏和脑组织中的SOD、CAT、GSH-Px的活力,降低MDA的含量(p0.05),从而改变机体抗氧化能力。蝇蛆肽对衰老小鼠的影响机制可能与增强其体内抗氧化酶活力及改变脏器指数相关。     

发育期补充DHA对大鼠空间学习记忆能力的影响

研究发育期补充DHA对大鼠空间学习记忆能力的影响.将144只初断乳雄性SD大鼠按照随机数字表法随机分为6组:阴性对照(正常饲料)组、阴性对照(EFA缺乏饲料)组、阳性对照(脑复康400 mg/( kg· d))组、DHA小、中、大剂量(150、300、600 mg/( kg·d))组,每组24只.分别在喂养4周、8周、12周时,Morris水迷宫进行行为学测试,并同步测定大鼠脑组织总蛋白含量、乙酰胆碱酯酶(AChE)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量以及血液血常规检查.水迷宫结果显示:喂养8周时,与阴性对照组相比,阳性对照组和DHA中剂量组逃避潜伏期均明显缩短(P＜0.05)、有效时间比和穿越平台次数均明显增加(P＜0.05);喂养12周时,与阴性对照组相比,DHA大剂量组潜伏期明显延长(P＜0.01),脑组织MDA含量明显增加(P＜0.05),SOD活性明显降低(P＜0.05);其余各组AChE、SOD活性、MDA含量差异均不显著.研究可以得出:DHA增强大鼠空间学习记忆具有明显的量效和时效关系;发育期长时间大剂量的补充DHA,会造成学习记忆能力下降,可能有一定的毒副作用.     

添加DHA的食用油对SD大鼠肝抗氧化活性的研究

为了研究添加DHA的食用油对肝抗氧化活性的影响,本文选取96只初断乳SD雄性大鼠(80±10)g,按照随机数字表法分为8组,阴性对照组(大豆油和花生油等比例混合)、阳性对照组(DHA藻油),以250、500、750 mg DHA分别调配入60 g大豆油、花生油中,作为DHA低、中、高剂量调配油的处理组。对各处理组按1 m L混合油/100 g体重·d喂养分别达到4周和8周时,对SD大鼠肝组织中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和乙酰胆碱酯酶(ACh E)活性进行检测。结果表明:DHA中剂量组大鼠肝组织SOD活性极显著高于阴性对照组(p0.01),MDA含量极显著低于阴性对照组(p0.01),ACh E活性无显著性差异(p0.05);DHA高剂量组肝组织SOD活性显著低于阳性对照组(p0.05),MDA含量显著高于阳性对照组(p0.05),ACh E无显著性差异(p0.05);其余各组ACh E、SOD活性及MDA含量均无显著性差异(p0.05)。适量补充DHA,有增强大鼠机体抗氧化的能力,然而一旦DHA摄入过量,反而会对机体抗氧化能力产生消极作用。     

玉米须多糖的提取工艺优化及抗氧化活性研究

研究了玉米须多糖的提取工艺条件和抗氧化活性。通过单因素试验和正交试验确定了最佳工艺参数,即超声处理次数350～450次,超声波功率300 W,浸提时间在5～6 h,乙醇体积分数约60%。并按200、400 mg/kg给老年大鼠连续灌胃30 d,测血清MDA含量,脑和肝组织脂褐质(Lf)含量,皮肤和肝组织羟脯氨酸(HYP)含量及血清SOD,CAT,GSH-Px活性。结果表明:两剂量组均能明显降低老年大鼠血清MDA含量及脑和肝组织Lf含量,明显提高血清SOD,CAT,GSH-Px活性及皮肤HYP含量。     

紫山药多糖对D-半乳糖衰老模型大鼠肝、脑的影响

目的:探讨紫山药多糖对D-半乳糖所致衰老模型大鼠的抗衰老作用及其作用机理。方法:以D-半乳糖建立大鼠衰老模型,灌胃紫山药多糖(20、100、500 mg/(kg·d))45 d后,检测大鼠肝、脑组织中总抗氧化能力(total antioxidant capacity,T-AOC)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力,检测谷胱甘肽(glutathione,GSH)及过氧化终产物丙二醛(malondialdehyde,MDA)含量,应用免疫印迹实验评价肝、脑中p53、p21蛋白的表达。结果:100 mg/(kg·d)紫山药多糖可显著提高D-半乳糖衰老模型大鼠肝、脑中T-AOC、GSH-Px活力、GSH含量,降低过氧化产物MDA含量,抑制衰老基因p53、p21的蛋白表达。结论:紫山药多糖具有显著的抗大鼠肝、脑衰老损伤的作用,作用机理可能与p53/p21信号通路有关。     

雨生红球藻虾青素对糖尿病大鼠脑损伤的干预作用

目的:研究雨生红球藻虾青素对2型糖尿病大鼠脑组织的影响。方法:72只大鼠随机分为糖尿病模型组、正常组、雨生红球藻虾青素低剂量组【50 mg/(kg·d)】、雨生红球藻虾青素中剂量组【100 mg/(kg·d)】、雨生红球藻虾青素高剂量组【200 mg/(kg·d)】、降糖药物(盐酸二甲双胍)组,每组12只。采用腹腔注射链脲佐菌素(STZ)加高糖高脂饲料制备大鼠2型糖尿病模型。12周后,10%水合氯醛麻醉处死大鼠,4℃下取其脑部,检测GSH-Px活性、SOD活性和MDA含量;HE染色光镜下观察大鼠脑组织形态结构;免疫组化测定大鼠脑组织含IL-1β、TNF-α的细胞数量。结果:与模型组比较,高剂量虾青素可显著提高2型糖尿病大鼠脑组织GSH-Px和SOD的活性,显著降低MDA的含量,显著降低IL-1β、TNF-α的细胞数量,对糖尿病大鼠脑组织结构具有保护作用。结论:雨生红球藻虾青素对2型糖尿病大鼠脑组织具有保护作用,其作用机制可能与改善大鼠脑的氧化应激反应,降低炎性因子有关。     

东北山核桃仁油对D-半乳糖衰老小鼠抗氧化能力的影响

研究东北山核桃仁油(Juglans mandshurica Oil,JMO)对D-半乳糖衰老小鼠抗氧化能力的影响。采用连续颈背部注射D-半乳糖建小鼠亚急性衰老模型的方法,造模6周。建模同时,以VC为阳性物质对照组,JMO低、中、高剂量组分别灌胃5、10、20mL/(kg.d),同时设模型对照组,灌胃生理盐水。6周后测定小鼠血清、肝脏、脑组织中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)和单胺氧化酶(MAO)的含量。结果表明:模型对照组血清、肝脏和脑组织匀浆中T-AOC、S OD、C A T、G S H-P x含量均显著降低,M AO和M D A含量显著升高,与正常对照组比较差异显著;1 0、2 0mL/(kg.d)中、高剂量JMO可显著提高衰老小鼠机体总抗氧化能力T-AOC水平,显著提高抗氧化酶SOD、CAT和GSH-Px的活性,明显降低MAO活性和脂质过氧化物MDA含量,与模型对照组比较有显著性差异。提示,JMO能抑制机体内脂质过氧化物的生成,有效清除机体内产生的过量自由基,显著提高亚急性衰老小鼠的抗氧化能力,具有量效关系。     

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