芥子酸改善高脂饮食模式下叙利亚仓鼠脂代谢与氧化应激水平

探讨芥子酸对高脂饮食仓鼠脂代谢和氧化应激的影响。比色法分别检测仓鼠血清和肝脏中总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-c)、低密度脂蛋白(LDL-c)、游离脂肪酸(NEFA),丙二醛(MDA)和总抗氧化力(T-AOC)水平。蛋白印迹法检测肝脏中PPAR-γ、CPT-1、ACC1、FAS、HMGCR、SREBP2和CYP7A1的表达。与高脂饮食组相比,芥子酸干预显著降低肥胖仓鼠体重(23.86%)、附睾脂肪(20.38%)和肾周脂肪(27.91%)指数(p0.05);改善血脂水平(至TG:183.51μmol/L、TC:1481.67μmol/L、HDL-c:507.81μmol/L、LDL-c:272.50μmol/L和NEFA:1.16 ng/L);分别降低MDA水平(至血清:7.85 nmol/L,肝脏:5.47 nmol/L)并提升T-AOC水平(至血清:12.63 U/mL,肝脏:113.72 U/mL)。芥子酸干预还能较高脂饮食组仓鼠显著提高PPAR-γ(2.00倍)、CPT-1(2.61倍)、CYP7A1(1.65倍),并显著抑制FAS(34.38%)、ACC1(52.73%)、SREBP2(53.49%)和HMGCR(32.68%)的表达水平(p0.05)。本研究提示,芥子酸能够显著改善高脂膳食诱导的仓鼠脂代谢紊乱,这与调控脂代谢相关蛋白的表达和减轻氧化应激水平有关。     

锦南复方对2型糖尿病大鼠血糖的辅助调节作用

本研究探讨了锦南复方对2型糖尿病大鼠的降糖作用。随机选取10只SD大鼠作为正常对照组,剩余40只采用高脂饮食喂养联合低剂量链脲佐菌素诱导2型糖尿病模型。将成模大鼠随机分为3组:模型组、阳性对照组(二甲双胍,200 mg/kg)、锦南复方组(锦南复方,500 mg/kg)。干预7周后,检测大鼠血糖、血脂、胰岛β细胞中γ-氨基丁酸(γ-aminobutyric acid,GABA)表达水平、Bax蛋白水平,RT-PCR检测肝脏中PPAR-α、PPAR-γ基因表达。电子扫描显微镜观察大鼠腹主动脉血管壁变化。结果表明,锦南复方组大鼠空腹血糖、餐后血糖、糖化血红蛋白、血清胰岛素、甘油三酯、总胆固醇、低密度脂蛋白、Bax蛋白相对表达量分别为18.45 mmol/L、21.39 mmol/L、8.97%、26.78 mIU/L、3.35 mmol/L、2.53 mmol/L、0.46 mmol/L、0.20,均显著低于模型组(p0.01);GABA、PPAR-α、PPAR-γ相对表达量为0.36、0.79、4.42,均显著高于模型组(p0.05)。锦南复方组大鼠血管内壁损伤程度低于模型组。推测降糖作用机制可能与增加胰岛GABA表达,启动PI3K/PKB通路,抑制胰岛β细胞凋亡,上调PPAR-α、PPAR-γ基因表达,加速肝脏脂肪酸的β氧化,减少脂肪酸含量有关。     

普洱茶改善高脂饲料饲喂大鼠的胰岛素抵抗作用

为研究普洱茶改善高脂饲料饲喂大鼠的胰岛素抵抗作用,将SD雄性大鼠随机分为5组,分别为正常对照组、高脂对照组和普洱茶低（0.45 g/kg·bw）、中（0.90 g/kg·bw）和高（1.35 g/kg·bw）剂量组。灌胃给药,测体重、空腹血糖（fasting blood glucose,FBG）、胰岛素（insulin,INS）及肝糖原水平,同时利用实时荧光聚合酶链式反应技术测定普洱茶对大鼠肝脏中葡萄糖激酶（glucokinase,GK）、肝糖原合成酶（glycogen synthetase 2,Gys-2）、葡萄糖-6-磷酸酶（glucose-6-phosphatase,G6pc）、胰岛素受体（insulin receptor,INSR）和附睾脂肪中葡萄糖转运蛋白-4（glucose transporter-4,GLUT-4）、过氧化物酶体增殖剂激活受体-γ（peroxisome proliferator activated receptor-γ,PPAR-γ）mRNA 表达水平的影响。结果显示：普洱茶能显著降低大鼠体重、脂肪系数、空腹血糖、胰岛素水平及G6pc表达水平,增加肝脏中GK、Gys-2和INSR表达水平,显著增加附睾脂肪组织中PPAR-γ和GLUT-4表达水平。结果表明,普洱茶能够通过增加GK、Gys-2、INSR、PPAR-γ和GLUT-4表达水平以及降低G6pc表达水平,改善大鼠的胰岛素抵抗状态,有效地降低血糖水平,从而预防II型糖尿病和胰岛素抵抗相关疾病的发生。     

复合蛋白肽对高脂饮食诱导肥胖大鼠糖脂代谢的影响

目的：探究复合蛋白肽对高脂饮食诱导肥胖大鼠糖脂代谢的改善作用。方法：将雄性SD大鼠随机分为肥胖模型组、空白对照组，肥胖模型组给予高脂饲料持续喂养4w,筛选肥胖敏感大鼠分为低(LPP)、中(MPP)、高(HPP)剂量组，饲料中复合蛋白肽的含量分别为25%、50%、100%,另设与低、中剂量组等热量饲喂的模型对照组1(MC1)和高剂量组等热量的模型对照组2(MC2)。给予复合蛋白肽干预4w后，检测各组大鼠体重与脂肪含量、肝脏脂肪蓄积以及棕色脂肪能量代谢相关蛋白情况。结果：复合蛋白肽能够显著降低肥胖大鼠的体重、脂肪含量及血脂水平，同时能够降低肝脏脂滴密度，增加线粒体氧化磷酸化复合物(OXPHOS)、解偶联蛋白1(UCP1)表达水平。结论：复合蛋白肽能降低肥胖大鼠体内脂肪含量和血脂水平，可能与增强棕色脂肪组织中OXPHOS和UCP1表达相关。     

辣木提取物降脂作用的研究

目的探讨辣木提取物预防性降脂的作用。方法选用SD雄性大鼠为研究对象,通过喂养高脂膳食建立预防性肥胖高血脂模型,用辣木提取物进行辅助降脂试验,依据保健食品功能学评价规程进行。大鼠随机分为正常对照组、高脂模型对照组、辣木提取物高剂量组、中剂量组、低剂量组,实验后检测各组大鼠体重、血液生化指标(总胆固醇、甘油三酯、低密度脂蛋白、高密度脂蛋白)、脂肪重量和脂/体比、Lee′s指数。结果大鼠灌胃辣木提取物40 d后,各实验组血脂水平明显低于高脂模型对照组,其中高剂量组的血清总胆固醇、甘油三脂与高脂模型对照组相比分别有显著性差异(P0.05)和极显著性差异(P0.01)。辣木提取物各剂量组大鼠的肾周脂肪重量和附睾脂肪重量、脂/体比、Lee′s指数极显著低于高脂模型对照组(P0.01)。结论辣木提取物具有良好的辅助降血脂作用。     

复合沙棘原液对高脂血症大鼠的降脂作用

目的:探究复合沙棘原液对高脂血症模型大鼠的降血脂作用的影响。方法:将60只Wistar大鼠随机分为空白对照组、高脂模型组、阳性对照组(洛伐他汀胶囊1.80 mg/kg·bw)、复合沙棘原液低(3.57 mL/kg·bw)、中(7.14 mL/kg·bw)、高(14.28 mL/kg·bw)剂量组,并通过高脂饲料喂养法构建高脂血症大鼠模型。空白对照组和高脂模型组灌胃等量生理盐水,实验组大鼠分别灌胃相应剂量的复合沙棘原液及洛伐他汀混悬液。给药28 d后,观察与分析各组大鼠的体重、Lee’s指数、血清血脂水平、抗氧化水平、肝脏指数及肝脏病理形态。结果:与空白对照组相比,高脂模型组大鼠体重、Lee’s指数均极显著升高(P<0.01),表明模型构建成功;阳性对照组、复合沙棘原液高剂量组与高脂模型组相比血清中总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)、丙二醛(malondialdehyde, MDA)含量均降低,高密度脂蛋白胆固醇(h...     

中链甘油三脂和共轭亚油酸复配食用油对大鼠脂肪囤积及认知功能的影响

为了研究中链甘油三脂和共轭亚油酸复配食用油对大鼠脂肪囤积及认知功能的影响,将SD大鼠随机分为对照（蒸馏水）、猪油、健康油脂和复配油脂组,灌胃大鼠4周,记录大鼠体重、摄食和饮水量;进行水迷宫测试;测定Lee’s指数、肾周、腹部、附睾和心外膜脂肪重量,以及血糖、肝功、血脂代谢、瘦素、TNF-α的水平;观察小肠和肝小叶组织结构变化。与对照组相比,猪油组大鼠肾周脂肪、附睾脂肪、心外膜脂肪重量、TNF-α和谷丙转氨酶显著升高;与猪油组相比,健康油脂组、复配组不同剂量大鼠空腹血糖值、谷丙转氨酶、TNF-α、肾周脂肪、附睾脂肪和心外膜脂肪重量显著降低;与对照和猪油组相比,复配油脂低剂量组的甘油三酯明显降低。复配油脂在控制甘油三酯水平和炎性反应上有一定优势。     

L-肉碱对肥胖大鼠体脂含量及肥胖基因表达产物的影响

为探讨L -肉碱对肥胖大鼠体重、体脂、胰岛素及肥胖基因表达产物 (瘦素 )等水平的影响 ,以高脂饲料诱导大鼠肥胖模型 ,将肥胖模型鼠随机分为 4组 :对照组与 12 5、2 5 0、5 0 0mg kgBW 3个剂量的L -肉碱组 ,每天 1次经口给予 ,共 6周。观察大鼠体重、睾丸 肾脂肪垫重量、胰岛素(INS)及瘦素 (Leptin)水平等的变化。结果显示 3个肉碱组的体重均低于对照组 ,2 5 0与5 0 0mg kgBW组的睾丸 肾脂肪垫重量、胰岛素和瘦素显著低于对照组 (P <0 0 5 ) ,提示L -肉碱具有抑制肥胖大鼠肥胖的作用。     

葛根素提取物改善妊娠期糖尿病大鼠的氧化应激损伤

本文研究葛根素提取物对妊娠期糖尿病模型大鼠氧化应激的作用。建立妊娠期糖尿病模型大鼠,采用葛根素提取物进行干预。检测大鼠空腹血糖(FPG)、高密度脂蛋白(HDL-C)、低密度脂蛋白(LDL-C)、丙二醛(MDA)、一氧化氮(NO)、超氧化物歧化酶(SOD)、白介素-6(IL-6)、C反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α),醌氧化还原酶1(NQO1)、血红素氧合酶-1(HO-1)及核因子E2相关因子2(Nuclear factor E2 related factor 2)Nrf2蛋白的含量水平。结果表明,葛根素高剂量组FPG、LDL-C和HDL-C分别为9.05 mmol/L、0.79 mmol/L和0.72 mmol/L(p<0.05);葛根素高剂量组MDA、NO和SOD分别为7.15 nmol/mg、90.76μmol/L和9.29 U/mg(p<0.05);葛根素高剂量组IL-6、CRP和TNF-α分别为135.51 ng/L、7.18 mg/L和15.06μg/μL(p<0.05)。结果说明葛根素提取物可降低空腹血糖,改善MDA、NO及SOD水平。     

L-阿拉伯糖对营养性肥胖大鼠的减肥作用研究

通过高脂饮食诱导建立营养性肥胖大鼠模型,研究L-阿拉伯糖(LA)对其的减肥作用。通过高脂饮食诱导60 d建立肥胖模型,灌胃给予治疗80 d,检测体重、血糖、肥胖指数(Lee’s指数)、脂肪湿重、脂肪系数和肝指数的变化情况。结果发现,灌胃治疗80 d后,与肥胖模型组相比,L-阿拉伯糖给药组能明显减轻肥胖大鼠体重,明显抑制血糖升高,明显降低Lee’s指数、脂肪湿重、脂肪系数和肝指数。L-阿拉伯糖对营养性肥胖大鼠有较好的减肥和降血糖效果。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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.     

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.     

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.     

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.