徽州贡菊总黄酮对D半乳糖致衰老小鼠的抗氧化作用

目的:探讨徽州贡菊总黄酮对衰老小鼠抗氧化作用的影响。方法:D-半乳糖致衰老模型法,采用200、400、800mg/(kg·dbw)剂量的徽州贡菊总黄酮给小鼠灌胃,检测血清和肝中超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GSH-Px)活性、过氧化氢酶(CAT)活性、总抗氧化能力(T-AOC)和血清、肝及脑中的MDA含量。结果:与模型组比较,不同剂量组能显著提高血清和肝组织中SOD、GSH-Px、CAT、T-AOC活性,降低血清、肝脏和脑组织中MDA含量。结论:徽州贡菊总黄酮具有一定的抗氧化功能。     

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。     

辣木多肽对D-半乳糖致衰老小鼠抗氧化功能的影响

探讨辣木多肽(MOPP)对D-半乳糖致衰老小鼠抗氧化能力的影响。小鼠腹腔注射D-半乳糖(120mg/kg)建立衰老模型。建模成功后,分设正常组,D-半乳糖衰老组,维生素C组,MOPP低剂量(10 mg/kg)和高剂量(100 mg/kg)组。连续给药6周后,依试剂盒说明分别测定血清总抗氧化力(T-AOC),脑、心脏和肝脏及血清中超氧化物歧化酶(superoxide dismutase,SOD),过氧化氢酶(catalase,CAT),谷胱甘肽过氧化酶(glutathioneperoxidase,GSH-Px)和丙二醛(malondiadehycle,MDA)水平。q RT-PCR法测定肝内Mn-SOD、Gu/Zn-SOD和CAT的m RNA表达。与衰老对照组相比,MOPP能分别有效提高衰老小鼠血清T-AOC能力(至13.73～17.98U/m L),及血清SOD(8.04～11.65 U/mg protein)、CAT(4.56～6.45 U/mg protein)和GSH-Px(7.28～10.65 U/mg protein)活性,并显著提升脑、心脏及肝组织中抗氧化物酶(SOD、CAT、GSH-Px)活力(p0.05)。同时,高浓度MOPP还能使血清、脑、心脏和肝组织中MDA水平显著降低43.6%,44.7%,31.4%和56.0%(p0.05)。此外,MOPP干预还能增强肝脏中SOD、CAT和GSH-Px的m RNA转录。本研究结果提示MOPP能明显提高D-半乳糖致老龄小鼠体内的抗氧化状态。     

覆盆子糖蛋白粗提物体内抗氧化作用研究

研究覆盆子糖蛋白粗提物对小鼠体内抗氧化作用.采用试剂盒测定小鼠血清、肝脏、脑中的丙二醛(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.实验结果表明:覆盆子糖蛋白粗提物可以提高受试小鼠血清、肝脏、脑中SOD、CAT及GSH-Px的活性,而降低这些组织中MDA的含量.说明覆盆子糖蛋白具有一定的抗氧化活性.     

蚕蛹多肽提高D-半乳糖致衰老小鼠的抗氧化及免疫能力

目的:研究蚕蛹多肽对D-半乳糖衰老模型小鼠抗氧化、提高免疫作用.方法:将昆明小鼠随机分为9组,包括空白组,衰老模型组,蚕蛹多肽(SPP)低、中、高剂量组,蚕蛹蛋白组,Vc组,谷胱甘肽组和鱼胶原蛋白肽组.除空白组外,其余8组腹腔注射D-半乳糖建立衰老模型,42d后眼球取血,颈椎脱臼处死小鼠,测定脑、肝脏中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)活性、总抗氧化能力(T-AOC)和丙二醛(MDA)含量,测定胸腺指数,脾指数,血清中白细胞数(WBC).结果:与衰老模型组相比,Spp中、高剂量组肝和脑中CAT、SOD、GSH-Px和T-AOC活力提高显著(p＜0.05或p＜0.01),同时SPP组肝和脑中MDA含量均有不同程度降低(p＜0.05或p＜0.01).此外,SPP能提高胸腺指数、脾指数与WBC,可以缓解小鼠衰老导致的免疫低下症状.与阳性对照蚕蛹蛋白组和鱼胶原蛋白肽组相比,SPP表现出更强的减缓小鼠衰老的作用,相当于等体外抗氧化效果的谷胱甘肽组.结论:SPP有较强的体内抗氧化活性和提高免疫功能,也为蚕蛹资源的回收利用提供思路.     

黄秋葵果实粉对衰老模型小鼠抗氧化能力的影响

探讨黄秋葵果实粉(OFP)对D-半乳糖致衰老模型小鼠抗氧化能力的影响。以昆明种小鼠为研究对象,颈背部皮下注射D-半乳糖造模。正常对照组、模型对照组饲喂基础饲料,实验组小鼠饲喂含受试物低、中、高剂量(32.00、64.00、128.00 g/kg)饲料,实验期56 d,测定血清和肝组织匀浆中超氧化物岐化酶(SOD)、谷胱苷肽过氧化物酶(GSHPx)、过氧化氢酶(CAT)的活性及丙二醛(MDA)的含量。D-半乳糖致衰小鼠SOD活性、GSH-Px活性和CAT活性均明显下降,MDA含量明显上升,与正常小鼠比较差异显著;饲喂不同剂量的黄秋葵果实粉后均能提高小鼠血清、肝脏组织中的SOD、GSH-Px和CAT活性,同时降低血清、肝脏组织中MDA含量。适量摄入黄秋葵果实粉能显著提高衰老小鼠的抗氧化能力,具有一定延缓衰老的作用。     

贡菊多糖对D-半乳糖致衰老小鼠的抗衰老作用

目的:探讨贡菊多糖对D-半乳糖所致衰老小鼠的抗衰老的作用。方法:将小鼠随机分为5组:空白对照组,D-半乳糖衰老模型对照组(80mg/kg·d bw),贡菊多糖低、中、高剂量组(50、100、150mg/kg·d bw),考察血清和肝中SOD、GSH-Px、CAT、T-AOC和血清、肝及脑中的MDA等指标。结果:贡菊多糖能拮抗D-半乳糖所致的小鼠衰老,使小鼠血清及肝组织SOD、GSH-Px、CAT、T-AOC活性明显回升,血清、肝脏和脑组织中MDA的水平下降。结论:贡菊多糖具有延缓衰老的作用。     

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.     

鸡骨胶原蛋白肽对D-半乳糖致衰小鼠抗氧化性的研究

目的:采用D-半乳糖注射昆明种成年小鼠,建立衰老模型,研究鸡骨胶原蛋白肽对D-半乳糖致衰小鼠抗氧化能力的影响。方法:昆明种成年小鼠,随机分为正常组、模型组、低剂量组、高剂量组及VE对照组。以小鼠血清、肝脏及脑组织中的SOD、GSH-Px、CAT的活性及MDA含量为指标,考察鸡骨胶原蛋白肽在体内的抗氧化性能。结果:鸡骨胶原蛋白肽能够显著提高致衰小鼠体内肝组织、脑组织中的GSH-Px、CAT(P<0.05)和SOD活力(P<0.05),而血清、肝组织和脑组织中的MDA含量(P<0.05)则显著降低。结论:摄入适当的鸡骨胶原蛋白肽可以有效地增强小鼠机体的抗氧化能力,从而延缓D-半乳糖诱发的小鼠衰老。     

水牛乳多肽对衰老模型小鼠机体抗氧化作用的研究

采用小鼠D-半乳糖致衰老模型,研究水牛乳多肽对亚急性致衰老小鼠机体抗氧化的作用,测定各模型组小鼠全脑、肝、心组织脏器指数以及小鼠血清、脑组织、心、肝中的丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化物酶(CAT)活性。结果表明:水牛乳多肽对小鼠脏器以及血清中SOD活性水平的升高有明显作用,其中,对小鼠心脏、全脑以及血清中SOD活性水平有显著影响(P<0.05),能明显降低小鼠脏器以及血清中的MDA含量,说明水牛乳多肽在一定程度上能够提高D-半乳糖模型衰老小鼠的抗氧化能力。     

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.     

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.     

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.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

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.