马齿苋多糖对四氯化碳诱导的小鼠急性肝损伤的保护作用

目的:探讨马齿苋多糖对CCl₄诱导的小鼠急性肝损伤的保护作用。方法:采用CCl₄建立小鼠急性肝损伤模型。随机将60只小鼠分成正常组、模型组、联苯双酯组(200 mg/kg·d)、马齿苋多糖低、中、高剂量组(1.5、3、6 g/kg/d),连续给药7 d后,除正常组小鼠外,其他各组小鼠腹腔注射0.2%CCl₄花生油10 mL/kg;采用ELISA法检测血清中AST、ALT和ALP含量及肝组织匀浆液中MDA、SOD、GSH和GSH-Px活性,HE染色观察肝组织病理学变化,Western Blot检测肝脏组织细胞核内Nrf-2和HO-1蛋白的表达水平。结果:与模型组比较,马齿苋多糖低剂量组能够显著性降低血清中ALP含量(P<0.05),同时显著性升高肝组织匀浆液SOD水平及Nrf-2蛋白表达水平(P<0.05);马齿苋多糖中剂量组能够显著性降低肝脏指数、血清中AST、ALT含量及肝组织匀浆液中MDA水平(P<0.05),同时显著性升高肝匀浆液中GSH、GSH-Px水平(P<0.05),极显著性降低血清中ALP含量和升高肝组织匀浆液中SOD水平及Nrf-2和HO-1蛋白表达(P<0.01);马齿苋多糖高剂量组能够显著性降低肝脏指数和血清中AST含量(P<0.05),同时显著性升高肝组织匀浆液中GSH和GSH-Px水平(P<0.05),极显著性降低血清中AST、ALP、MDA含量(P<0.01),同时极显著性升高肝组织匀浆液中SOD水平及Nrf-2和HO-1蛋白表达水平(P<0.01);另外,肝组织病理学观察结果表明,马齿苋多糖可以减轻CCl₄对肝脏的病理损伤。结论:马齿苋多糖对CCl₄诱导的肝损伤有一定的保护作用,其机制与激活Nrf-2/HO-1信号通路有关。     

美味牛肝菌多糖对急性肝损伤小鼠的保肝作用

用不同剂量的美味牛肝菌多糖(Boletus edulis polysaccharides,BEP)给予小鼠灌胃连续30d后,按10mL/kg剂量腹腔注射含体积分数0.2%CCl4的花生油溶液,建立CCl4诱导小鼠肝损伤模型。测定肝脏指数、肝脏重量、血清谷丙转氨酶(ALT)、谷草转氨酶(AST),以及肝组织中超氧化物岐化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)及还原型谷胱甘肽(GSH)水平,并进一步观察肝脏组织病理学变化。结果表明:BEP能显著抑制CCl4急性肝损伤小鼠肝脏指数、血清ALT、AST水平以及肝脏MDA含量的升高,提高肝脏GSH-Px、SOD及GSH活性,其中800 mg/(kg BW獉d)剂量水平效果最佳,BEP对CCl4急性肝损伤小鼠有一定的保护作用。     

大豆皂苷对四氯化碳致肝损伤小鼠肝脏氧化应激的干预作用

研究大豆皂苷对四氯化碳(CCl4)所致急性肝损伤小鼠肝脏氧化应激的干预作用。将实验小鼠按体重随机分为5组,即正常对照组、模型对照组、水飞蓟素组(阳性对照组)及大豆皂苷高、低剂量组。每日给药1次,连续7 d。实验末期,除正常对照组外,其余组小鼠腹腔注射CCl4建立急性肝损伤模型,比色法检测血清白蛋白(Alb)含量、血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、碱性磷酸酶(ALP)活性以及肝脏超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPx)活性及还原型谷胱甘肽(GSH)、丙二醛(MDA)含量。结果显示,大豆皂苷明显增高CCl4致急性肝损伤小鼠血清Alb水平,降低血清ALT、AST和ALP活性;升高肝组织总SOD、CAT和GPx活性,提高肝GSH水平,降低肝MDA水平;升高肝线粒体Na+-K+-ATPase、Ca2+-Mg2+-ATPase和Mn-SOD活性,降低肝线粒体MDA含量。这说明大豆皂苷可降低CCl4致急性肝损伤小鼠肝脏氧化应激,对肝损伤具有保护作用。     

芸豆芽菜多酚对氧化损伤小鼠体内抗氧化及肝脏损伤修复作用

本实验探究了芸豆芽菜多酚对D-半乳糖造模的氧化损伤小鼠体内抗氧化及肝脏损伤修复作用。腹腔注射D-半乳糖溶液构建氧化损伤小鼠模型,经连续灌胃不同剂量(20、40、60 mg/(kg·d))芸豆芽菜多酚28 d后测定小鼠体质量、肝脏脏器系数、血清超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate transaminase,AST)活力及丙二醛(malondialdehyde,MDA)含量并取肝脏制作苏木精-伊红染色切片,观察小鼠肝脏损伤及修复状况。与模型对照组小鼠比较,各灌胃给药组小鼠体质量及肝脏脏器系数无显著性差异(P0.05),芸豆芽菜多酚中、高剂量组小鼠血清SOD、GSH-Px活力显著上升(P0.05),MDA含量显著下降(P0.05),肝脏功能指示指标ALT与AST活力显著下降(P0.05),且综合肝组织病理学染色切片结果观察发现芸豆芽菜多酚可使肿胀的肝细胞恢复正常形态,并可减少胞间出血点及炎性细胞浸润现象,且作用效果与剂量呈正相关。     

黑米对高脂膳食饲喂雄性小鼠抗氧化相关基因的调控

目的:研究黑米对高脂喂养小鼠血清、肝脏和脑组织抗氧化水平以及肝脏抗氧化相关基因表达的影响。方法以喂养高脂高胆固醇膳食的雄性C57BL/6J小鼠为动物模型随机分为四组,每组12只,以高脂高胆固醇膳食组为对照组(C组,52.6 g玉米淀粉/100 g粮)、三个实验组分别在小鼠高脂饲料中补充白米(C+W组,52.6 g白米/100 g粮)和黑米(C+BL,26.3 g黑米/100 g粮和C+BH,52.6 g黑米/100 g粮)。8周后收集血液及组织进行检测,测定血清、肝脏和脑组织中总超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)和丙二醛含量(MDA)水平以及肝脏抗氧化相关基因SOD、CAT、GSH-Px、HO-1、NF2L2等的mRNA表达。结果:白米组(C+W)血清、肝脏及脑中SOD、GSH-Px、CAT活性和MDA含量较高脂对照组无统计学差异,C+BL组(P<0.05)和C+BH组(P<0.01)血清中SOD酶活力较对照组升高,且C+BH组MDA含量显著降低(P<0.05);与高脂组相比,黑米实验组(C+BL和C+BH)肝脏中SOD酶活性显著升高(P<0.05),C+BH组MDA含量显著降低(P<0.05);C+BH组脑中GSH-Px酶活性与高脂组相比显著升高(P<0.05),C+BL组(P<0.05)和C+BH组(P<0.01)脑中SOD酶活较对照组升高,C+BH组MDA含量显著降低(P<0.05)。RT-PCR结果显示,与高脂组相比,黑米添加组(C+BL和C+BH)SOD2、CAT mRNA表达极显著上调(P<0.01),GSH-Px mRNA表达显著上调(P<0.01),C+BH组HO-1 mRNA表达水平显著升高(P<0.05)。结论:高脂膳食造成氧化应激,黑米膳食干预抗氧化可能是增加抗氧化酶的表达来减少氧化损伤。     

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.     

酵母源金属硫蛋白排汞及对汞致肝脏及机体氧化损伤的修复作用

目的:探讨两种酵母源金属硫蛋白(metallothioneins,MT)-1、MT-2对氯化汞急性汞中毒小鼠排汞及对汞致肝脏及机体氧化损伤的修复作用。方法:氯化汞急性汞中毒小鼠模型通过颈部皮下注射氯化汞生理盐水溶液构建,急性汞中毒小鼠经连续灌胃二巯基丙磺酸钠(dimercaptopropansulfonate sodium,DMPS)及不同剂量(0.16、0.40、0.80 mg/(kg·d))酵母源MT 14 d后,测定小鼠体质量、肝脏脏器系数、血液及肝脏Hg~(2+)的含量、血清谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力、超氧化物歧化酶(superoxide dismutase,SOD)活力、机体总抗氧化能力(total antioxidative capacity,T-AOC)及丙二醛(malondialdehyde,MDA)含量和两项肝功能指示指标:谷丙转氨酶(alanine aminotransferase,ALT)及谷草转氨酶(aspartate transaminase,AST)活力。结果:相较于正常组小鼠,模型组小鼠体质量下降、肝脏脏器系数上升,差异具有统计学意义(P0.05);血液及肝脏Hg~(2+)含量显著上升(P0.05);血清GSH-Px、SOD活力及T-AOC显著降低(P0.05),MDA含量显著升高(P0.05);两项肝功能指标ALT及AST活力显著升高(P0.05)。经灌胃给药处理后,与模型组小鼠相比,酵母源MT中、高剂量处理组及二巯基丙磺酸钠阳性对照组小鼠体质量均显著上升(P0.05),并与正常组小鼠无显著性差异(P0.05);各给药处理组小鼠脏器系数均较模型组小鼠显著下降(P0.05)且呈一定的剂量-效应关系。各灌胃给药处理组小鼠血液及肝脏Hg~(2+)含量均不同程度下降;血清GSH-Px、SOD活力及T-AOC均不同程度回升,MDA含量及两项肝功能指标ALT及AST活力均不同程度降低。在0.16~0.80 mg/kg剂量范围内,高剂量酵母源MT给药效果最佳,与其他灌胃给药处理组差异显著(P0.05)。结论:两种酵母源MT对急性汞中毒小鼠具有良好的结合机体内游离Hg~(2+)及修复肝脏损伤及机体氧化损伤作用,且作用效果与给药剂量呈正相关。     

竹叶黄酮对CCl4所致小鼠肝细胞损伤的保护作用

以研究竹叶黄酮对CCl4所致小鼠肝细胞损伤的保护作用为目的,通过建立CCl4损伤肝细胞模型,观察不同剂量的竹叶黄酮对谷丙转氨酶(ALT)、谷草转氨酶(AST)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)、肝糖元含量的影响,并观察空白对照组、模型组及各剂量组肝组织石蜡切片的病变情况.结果显示,与空白组相比,模型组ALT、AST、MDA显著升高(p＜0.05),肝糖元含量、GSH-Px和SOD活性明显下降(p＜0.05).与模型组比较,在各剂量竹叶黄酮的影响下,ALT、AST和MDA含下降(p＜0.05),GSH-Px、SOD活性和肝糖元含量显著升高(P＜0.05),并呈剂量依赖性,肝组织病变程度明显低于模型组.本实验证明竹叶黄酮对CCl4所致小鼠肝细胞损伤有较好的保护作用.     

美拉德反应对金带细鲹鱼肉蛋白酶解物体内抗氧化性的影响

本文研究了金带细鲹鱼肉蛋白酶解物及其美拉德反应修饰物在动物体内的抗氧化性,通过检测灌胃30 d的对照组和各剂量组小鼠血清和肝脏中丙二醛(MDA)含量、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、谷胱甘肽(GSH)含量等指标的变化来研究修饰产物在动物体内的抗氧化活性。结果表明:酶解物及其美拉德反应修饰产物均能降低小鼠血清和肝脏中MDA的形成,增加小鼠血清及肝脏中SOD、GSH-Px的活力和GSH的含量,尤其是高剂量组的抗氧化效果明显,抗氧化活性随剂量的增加而增强,美拉德反应修饰产物能够显著增强小鼠血清及肝脏中SOD、GSH-Px的活力和GSH的含量(p0.05)。这表明,美拉德修饰反应可提高金带细鲹鱼肉蛋白酶解物在小鼠体内的抗氧化活性,修饰产物在小鼠体内的抗氧化性可能与其清除自由基能力有关。     

仙草提取物对CCl_4致小鼠肝损伤的保护作用

将70只雄性昆明小鼠随机分成7组:正常对照组、模型对照组、阳性对照组、醇提组、水提低、中、高剂量组.醇提组按500 mg/kg灌胃仙草醇提物,低、中、高剂量组分别按200、500、1 000mg/kg灌胃仙草水提物,阳性对照组按200 mg/kg灌胃联苯双酯,正常对照组和模型对照组以等体积蒸馏水灌胃,连续30 d.以CCl_4制成小鼠肝脏损伤模型,检测并比较各组小鼠血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)活性和血清白蛋白(Alb)、甘油三酯(TG)含量,肝组织匀浆中丙二醛(MDA)含量和超氧化物歧化酶(SOD)、谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-PX)活性.仙草水提物低、中、高剂量组与模型对照组相比均能显著降低ALT(P<0.05)、AST、TG值(P<0.01),显著增加Alb含量(P<0.05),极显著降低小鼠肝组织匀浆MDA值(P<0.01),极显著升高GSH、GSH-PX值(P<0.01),对SOD酶活性(P>0.05)无显著影响;同时,仙草水提物低、中、高剂量组与联苯双酯阳性对照组相比各指标无显著差异(P>0.05),而仙草醇提物与模型对照组相比上述各生化指标无显著差异(P>0.05).仙草水提物对CCl_4所致的小鼠肝损伤具有一定保护作用.     

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.     

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.     

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