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1.
赵娟娟  熊汇竹  刘维维  石文  何慧 《食品科学》2018,39(11):201-206
目的:研究富硒玉米肽(selenium-enriched corn peptides,SeCPs)对扑热息痛(acetaminophen,APAP) 代谢相关酶的影响及其对肝损伤的防护作用。方法:利用碱醇液提取玉米蛋白,经酶解和超滤制备分子质量 小于5 kDa的混合玉米肽。建立扑热息痛致小鼠肝损伤模型,测定小鼠肝脏指数、血清谷草转氨酶(aspartate aminotransferase,AST)活力、肝脏中细胞色素P4502E1(cytochrome P4502E1,CYP2E1)、细胞色素P4501A2 (cytochrome P4501A2,CYP1A2)、谷胱甘肽巯基转移酶(glutathione S-transferase,GST)、尿苷二磷酸葡萄糖 醛酸转移酶(uridine diphosphate-dependent glycosyltransferase,UGT)质量浓度、磺基转移酶(sulfotransferase, SULT)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力及还原型谷胱甘肽(glutathione,GSH)含 量,苏木精-伊红(hematoxylin-eosin,HE)染色观察肝脏病理学变化。结果:与模型组相比,SeCPs组小鼠其肝脏 中的CYP2E1、CYP1A2、UGT质量浓度及SULT活力显著降低(P<0.05),GSH含量、GST质量浓度及GSH-Px活 力显著提高(P<0.05),肝脏指数和血清中AST活力明显降低,肝脏病理学情况显著改善。结论:SeCPs对过量扑 热息痛致肝损伤的防护作用效果显著性优于亚硒酸钠+玉米肽,即有机硒与玉米肽有良好的协同保肝作用。  相似文献   

2.
目的:通过大鼠毒性干预实验观察枸杞汁对邻苯二甲酸二(2-乙基己基)酯(di-(2-ethylhexyl)phthalate,DEHP)染毒大鼠肝脏中尿苷二磷酸葡萄糖醛酸转移酶1(uridine diphosphate glucuronosyltransferase 1,UGT1)活性及代谢解毒的影响,探讨枸杞汁对DEHP代谢的干预效果。方法:60只雄性大鼠随机分为对照组、DEHP组和枸杞汁干预组,每组20只,DEHP组和干预组在DEHP一次染毒(3 000 mg/kg mb)后连续7 d分别灌胃生理盐水和枸杞汁,对照组则给予同等体积的芝麻油或生理盐水,期间每天收集大鼠24 h尿液。在染毒1、3、5、7 d后各组分别随机处死5只。采用试剂盒检测肝脏UGT1的活力,高效液相色谱法检测血清中的邻苯二甲酸单(2-乙基己基)酯(mono-(2-ethylhexyl)phthalate,MEHP)以及尿液MEHP和邻苯二甲酸(phthalic acid,PA)含量。结果:枸杞汁干预组大鼠第5天UGT1活性显著高于DEHP组和对照组(P0.05),且相对于DEHP组血清中MEHP含量减少而尿液中MEHP和PA含量增加。结论:枸杞汁可能通过提高UGT1活力促进了DEHP的代谢与排泄,发挥了解毒效应,将来可能作为一种预防或对抗邻苯二甲酸酯类物质或其他有毒化学物潜在危害的保健药材或功能食品用于人群的健康防护。  相似文献   

3.
为探究丹参素(Salvianic acid,SA)对高脂血症大鼠的调节作用及机制,将40只SD大鼠随机分为正常对照组(S,n=10)、高血脂模型组(M,n=10)、丹参素高剂量组(SAH,n=10)和低剂量组(SAL,n=10)。高脂饲料喂养建立高脂血症模型,边造模边灌胃给药。8周后,采用ELISA法测定各组大鼠血清中总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、载脂蛋白AI(apo AI)和载脂蛋白B(apo B)的含量;RT-PCR和Western-blot检测卵磷脂胆固醇脂酰基转移酶(LCAT)和胆固醇7α-羟化酶(CYP7A1)的表达;HE染色检测肝脏组织病理学形态。结果发现丹参素能明显降低模型大鼠TC、TG、LDL-C和apo B含量(p0.05),上调HDL-C、apo AI、LCAT和CYP7A1的表达,同时减轻肝脏脂肪病变,高剂量组效果更显著。因此,丹参素对高血脂大鼠血脂紊乱的调节作用机制可能与调控脂质代谢载脂蛋白、LCAT和CYP7A1的表达有关。  相似文献   

4.
目的:探讨血管紧张素转移酶2(ACE2)在糖尿病致大鼠肝脏氧化应激损伤中的作用和可能机制。方法:24只健康雄性SD大鼠,随机选取8只作为正常对照组,剩余16只按60mg/kg(以体质量计)一次性腹腔注射STZ溶液制备糖尿病肝脏氧化应激损伤模型,成模后大鼠随机分为2组:糖尿病组和胰岛素治疗组(优泌林 3.7×10-8mol/d),30d后宰杀,取血液和肝脏组织等进行各指标测定:1)测定血清中AGEs含量;2)测定肝脏组织中过氧化氢(H2O2)、丙二醛(MDA)的含量及过氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活力;3) 肝脏组织中血管紧张素Ⅱ(AngⅡ)、血管紧张素1-7(Ang1-7)的含量,ACE和ACE2酶活力的测定。结果:1)正常对照组大鼠空腹血糖均值为(5.39±0.30)mmol/L,糖尿病组大鼠空腹血糖均值持续维持在(28.24±2.51)mmol/L(远高于高水平高血糖状态指标值16.6mmol/L),胰岛素治疗后大鼠空腹血糖水平明显下降至(11.18±1.26)mmol/L,显著高于正常对照组(P<0.05),但同时显著低于糖尿病组(P<0.05),且治疗后期已经低于10.0mmol/L并逐渐接近正常对照组。糖尿病组大鼠血清中的AGEs的含量显著高于正常对照组和胰岛素治疗组(P<0.05)。2) 与正常对照组和胰岛素治疗组相比,糖尿病组大鼠肝脏组织中的MDA和H2O2极显著增多(P<0.01),SOD和GSH-Px的活力极显著降低(P<0.01); AngⅡ的含量显著增多(P<0.01),Ang1-7含量显著降低(P<0.01),ACE的酶活力显著升高(P<0.01),而ACE2的酶活力显著降低(P<0.01)。 结论: 糖尿病时大鼠肝脏组织局部AngⅡ显著升高,ACE2活力下降,肝脏组织处于氧化应激状态。胰岛素治疗后,ACE2活力增高,致AngⅡ降解,AngⅡ含量显著降低,肝脏的氧化应激减缓,提示ACE2对糖尿病大鼠肝脏氧化应激损伤有一定的保护作用,其机理可能与对AngⅡ降解作用增强有关。  相似文献   

5.
目的:研究绿茶水提物对铝暴露大鼠脑组织氧化应激的干预作用。方法:将雄性SD大鼠分为空白对照组、染铝组、绿茶水提物干预组、绿茶水提物阳性对照组,饲料染铝(111.9 mg/kg BW),用绿茶水提物(1.5%)进行干预,试验4周。采用ICP-MS法测定血清及脑铝含量,试剂盒法定量测定大鼠脑组织丙二醛(MDA)含量、乙酰胆碱酯酶活力、抗氧化酶活力及还原型谷胱甘肽(GSH)含量,并测定血清谷胱甘肽还原酶(GR)、谷胱甘肽-S-转移酶(GST)、谷胱甘肽过氧化物酶活(GSH-Px)。结果:绿茶水提物显著降低铝暴露大鼠血清铝含量(P0.01),以及铝元素在脑组织中的蓄积(P0.01),有效抑制脑组织中MDA的生成量,显著增加脑组织及血清的抗氧化能力。结论:绿茶水提物具有抗氧化和减缓脂质过氧化的作用,对铝暴露引起的大鼠脑组织氧化应激具有保护作用。  相似文献   

6.
探究甜叶菊提取物对脂质代谢、氧化应激和肠道微生态的影响。选取健康昆明鼠,构建脂代谢紊乱模型,分析其血脂、氧化应激及其肠道菌群变化。甜叶菊提取物显著降低了血脂(甘油三酯、胆固醇、低密度脂蛋白和游离脂肪酸)含量,显著提高了血清中抗氧化酶[超氧化物歧化酶(superoxide dismutase, SOD)和谷胱甘肽氧化物酶(glutathione peroxidase, GSH-Px)]水平,降低了丙二醛含量。病理组织切片显示,甜叶菊提取物显著改善了肝脏和结肠组织的损伤。高通量测序结果显示提取物提高了肠道拟杆菌水平,降低了厚壁菌水平。甜叶菊提取物能够调节脂质代谢,维持氧化应激平衡,抑制肝脏脂质堆积,同时具有益生元活性。  相似文献   

7.
目的研究夏枯草水提物对吡唑-脂多糖诱导的小鼠肝脏损伤的保护作用。方法将42只小鼠随机分为6组:正常对照组、模型组、夏枯草水提物低、中、高剂量组以及阳性对照组。灌胃给予小鼠夏枯草水提物,同时采用腹腔注射吡唑-脂多糖造成小鼠肝损伤模型,检测血清谷丙转氨酶(ALT)、谷草转氨酶(AST)和肝组织过氧化氢(H2O2)、丙二醛(MDA)、过氧化氢酶(CAT)、总超氧化物歧化酶(T-SOD)和谷胱甘肽(GSH)的活性/含量以及细胞色素酶CYP2E1和CYP2A5的蛋白表达水平。结果吡唑-脂多糖能够引起提高CYP2E1和CYP2A5的蛋白表达以及肝脏氧化应激并造成肝损伤;夏枯草水提物能够显著降低CYP2E1和CYP2A5的蛋白表达,降低氧化产物H2O2和MDA的含量,以及提高抗氧化系统中CAT、T-SOD活性和GSH含量。结论研究表明夏枯草可能通过抑制CYP2E1和CYP2A5的蛋白表达降低吡唑-脂多糖诱导肝组织内的氧化应激,从而对吡唑-脂多糖引起的肝损伤起保护作用。  相似文献   

8.
目的:基于胰岛素-铁代谢交互作用探讨膳食脂肪酸构成对肝脏糖水平的影响。方法:21日龄清洁级雄性SD大鼠60只,随机分为:对照组、15%大豆油组(15%SO)、15%猪油组(15%PO)、15%橄榄油组(15%OO)、15%鱼油组(15%FO)及1∶1 SO∶FO组。首先以气相色谱法测定油脂脂肪酸构成,之后以不同油脂干预大鼠13周,测定其肝脏葡萄糖、胰岛素含量,检测血红蛋白、血清铁、铁蛋白以及肝脏中的铁含量,以普鲁士蓝染色观测肝脏组织铁沉积情况,以实时荧光定量聚合酶链式反应(qRT-PCR)检测大鼠肝脏组织铁代谢关键基因的表达量。结果:SO中n-6不饱和脂肪酸含量为46.37%,FO中n-3不饱和脂肪酸含量为37.55%,PO中饱和脂肪酸含量为24.78%,OO中单不饱和脂肪酸含量为36.39%。各组大鼠肝脏中葡萄糖含量无明显差异,而1∶1 SO∶FO组大鼠肝脏胰岛素水平显著低于对照组及15%SO组(P<0.05)。各组大鼠血红蛋白及铁蛋白含量无显著性差异,而15%SO组血清铁含量最高且显著高于对照组及1∶1 SO∶FO组(P<0.05)。与对照组相比,15%PO组肝脏铁含量...  相似文献   

9.
目的:初步探讨沙棘熊果酸对酒精性肝损伤大鼠肝法尼醇X受体(Farnesoid X receptor, FXR)信号通路关键蛋白表达的影响。方法:6周龄SPF级SD大鼠随机分为4组,每组9只,分别为正常对照组、酒精模型组、熊果酸对照组和熊果酸+酒精组,干预时间为8周。采用苏木精-伊红(H&E)染色法观察大鼠肝组织病理学变化;测定大鼠血清中谷丙转氨酶(Alanine aminotransferase,ALT)、谷草转氨酶(Aspartateaminotransferase,AST)活力和血清总胆汁酸(Total bile acid,TBA)、肝脏甘油三酯(Triglyceride,TG)、总胆固醇(Total cholesterol,TC)含量;酶联免疫吸附(Enzyme linked immunosorbent assay,ELISA)法检测血清细胞因子肿瘤坏死因子α(Tumor necrosis factor-α,TNF-α)、白细胞介素1β(Interleukin 1β,IL-1β)、白细胞介素10(Interleukin 10,IL-10)含量;免疫印迹法(Western blotting)测定大鼠肝FXR信号通路相关蛋白表达情况。结果:与正常对照组相比,酒精模型组大鼠肝脏存在大小不一的脂肪空泡和大量炎性细胞浸润;血清ALT、AST活力,TNF-ɑ、IL-1β水平,TBA含量和肝脏TG、TC含量均显著升高(P<0.05)、IL-10水平显著下降(P<0.05)。经熊果酸干预后,肝脏脂肪变性得到明显改善,炎性细胞浸润减少;血清ALT、AST活力,TNF-ɑ、IL-1β水平,TBA含量和肝脏TG含量均有不同程度的显著下降(P<0.05),IL-10水平显著提高(P<0.05)。Western blotting结果显示,与正常对照组相比,模型组大鼠肝脏FXR蛋白表达显著降低(P<0.05),CYP7A1和SREBP-1c蛋白表达均显著升高(P<0.05);而经熊果酸干预后,FXR蛋白表达明显提高,CYP7A1及SREBP-1c蛋白表达明显下调,且差异均具有统计学意义(P<0.05)。结论:沙棘熊果酸能够明显改善酒精诱导的肝脏损伤,其作用机制可能与上调肝FXR、抑制CYP7A1和SREBP-1c的蛋白表达,从而维胆汁酸稳态、调节脂质代谢有关。  相似文献   

10.
目的:研究无斑鹞鲼肉对大鼠脂质代谢的影响,以提高低值水产品的利用价值。方法:将SD 大鼠分3 组,对照组(酪蛋白)、10% 鹞鲼肉组(酪蛋白+ 鹞鲼肉)和20% 鹞鲼肉组。分别测定大鼠血清甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、游离脂肪酸(FFA)浓度,以及肝脏TG、TC、磷脂(PL)浓度,并测定肝脏脂质代谢相关酶--葡萄糖-6- 磷酸(G6PDH)脱氢酶、苹果酸酶、脂肪酸合成酶、磷脂酸磷酸酶和肉碱棕榈酰转移酶的活性。结果:摄食鹞鲼肉可显著降低大鼠血清TG、TC 和FFA 含量(P < 0.05),对血清HDL-C 浓度无明显影响,但能显著降低大鼠动脉硬化指数(AI)。另外,鹞鲼肉可明显降低肝脏TG 和TC 含量(P < 0.05),抑制肝脏脂肪合成相关酶的活性,但对脂肪酸分解酶活性则未见明显影响,同时FAS、CPT-1、CPT-2 mRNA 表达量也无明显变化。结论:摄食无斑鹞鲼肉具有降低大鼠血清和肝脏脂肪含量的作用,主要是通过抑制脂肪酸和TG 的合成实现。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

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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.  相似文献   

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<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  相似文献   

19.
《印刷工业》2014,(11):95-95
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%.  相似文献   

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《印刷工业》2014,(8):103-103
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  相似文献   

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