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1.
为研究海参蛋白肽对脂多糖(LPS)诱导小鼠RAW264.7巨噬细胞炎症反应的抑制作用及作用机制,本研究利用LPS刺激RAW264.7巨噬细胞建立炎症模型,采用Griess法测定细胞一氧化氮(NO)含量,实时荧光定量PCR测定细胞内诱导型一氧化氮合酶(i NOS)、肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、白介素-6(IL-6)以及血红素氧合酶-1(HO-1)m RNA表达。结果表明,海参蛋白肽以浓度依赖效应显著抑制LPS诱导RAW264.7巨噬细胞NO生成以及TNF-α、IL-1β、IL-6和i NOS m RNA表达(p0.05),显著提高细胞内HO-1 m RNA表达(p0.05)。HO-1抑制剂锌原卟啉Ⅸ(Zn PP-Ⅸ)部分逆转海参蛋白肽对LPS诱导RAW264.7巨噬细胞炎症反应的抑制作用。具有抗炎活性的海参蛋白肽富含甘氨酸、谷氨酸和天冬氨酸,分子量180~1000 u的组分为72.12%。这些结果说明海参蛋白肽通过上调细胞HO-1 m RNA表达发挥抑制LPS诱导RAW264.7巨噬细胞炎症反应的作用。  相似文献   

2.
目的:研究鹿皮蛋白酶解相关工艺,并对其酶解产物作出功效性评价。方法:以水解度作考察指标筛选酶制剂,运用响应面实验优化水解工艺参数,并研究水解液对RAW 264.7巨噬细胞增殖、NO分泌、LZM活力以及细胞因子TNF-α和IL-6分泌表达的影响。结果:表明以碱性蛋白酶酶解鹿皮蛋白的最适合条件是酶底比5%、pH=9、酶解时间5 h、酶解温度60 ℃,在此参数下水解度为48.64%。鹿皮蛋白酶解产物浓度为200.00 μg/mL时,可以显著提高RAW 264.7细胞的NO浓度,达到最大值(10.82 mmol/mL);显著促进RAW 264.7细胞中的LZM活性;显著增加免疫因子TNF-α、IL-6的分泌(P0.05)。结论:响应面法可较好地应用于鹿皮蛋白酶解工艺的优化,鹿皮蛋白酶解产物具有显著的免疫活性,研究结果可为鹿皮蛋白的高值化开发提供理论基础。  相似文献   

3.
以榆黄菇为原料,采用水提醇沉法提取榆黄菇粗多糖,Sevage法去除蛋白,利用DEAE-Cellulose离子交换和Superdex-75凝胶层析方法纯化获得PSI和PSII两个组分;通过脂多糖(LPS)刺激建立炎症模型;利用MTT法筛选出两个多糖的优势浓度,采用吸光度分析法测定一氧化氮合酶(NOS)的活力、酶联免疫吸附试剂盒测定细胞因子IL-1β、IL-6和TNF-α的分泌水平来评价多糖对RAW264.7细胞的抗炎作用。研究结果显示,LPS浓度为5 μg/mL时,细胞炎症水平达到最高,在模型的基础上筛选出PSI的优势浓度为500 μg/mL、PSII的优势浓度为200 μg/mL;与LPS模型组相比较,PSI对NOS活性、IL-1β、IL-6和TNF-α的分泌水平抑制率分别为37.54%、28.84%、28.27%和30.25%,PSII对NOS活性、IL-1β、IL-6和TNF-α的分泌水平抑制率分别为51.24%、37.56%、31.35%和32.67%。研究证实,榆黄菇多糖PSI和PSII对LPS诱导RAW264.7炎症细胞具有缓解作用,主要表现在抑制炎症细胞因子的分泌水平、促进细胞增殖、降低巨噬细胞的吞噬能力等方面,而对比PSI来说,PSII对于一氧化氮合酶(NOS)以及细胞因子IL-1β、IL-6和TNF-α的分泌水平的抑制力要更强,具有更好的抗炎效果。  相似文献   

4.
夏炎  管晓辉  崔艳艳  高超  陈玲  董然  沈明浩 《食品科学》2017,38(19):182-188
探讨蒲公英糖蛋白(glycoprotein from Taraxacum,TG)对由脂多糖引起的RAW264.7细胞炎症的抗炎效果,并阐明其活性的基本分子机制。利用脂多糖刺激RAW264.7细胞,建立体外炎症模型,采用噻唑蓝比色法检测TG对RAW264.7细胞的增殖毒性,Griess试剂法检测了一氧化氮(nitric oxide,NO)的分泌情况,反转录聚合酶链式反应检测炎症细胞因子——白细胞介素-6(interleukin 6,IL-6)和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)m RNA以及诱导型一氧化氮合酶(inducible nitric oxide synthase,i NOS)m RNA的表达水平,酶联免疫吸附测定法测定IL-6和TNF-α的分泌量,Western blot检测P-IκB-α蛋白的表达水平,用以研究TG对核转录因子-κB(nuclear factor-kappa B,NF-κB)信号转导通路的抑制作用。结果表明:TG能够显著甚至极显著地抑制NO的分泌,IL-6、TNF-α、i NOS的m RNA的表达,IL-6和TNF-α的分泌(P0.05、P0.01)。TG高度显著上调了IκB-α的蛋白表达(P0.001),并显著下调了P-IκB-α的蛋白表达(P0.05),且与TG质量浓度成正比。其中在TG质量浓度为250、500、1 000μg/m L时对TNF-α分泌量的抑制率分别为28.6%、65.4%、89.3%,对IL-6分泌量的抑制率分别为32.3%、54.1%、85.7%。TG间接抑制了NF-κB信号转导途径,有显著的体外抗炎效果且抗炎效果与TG的质量浓度呈剂量依赖性。  相似文献   

5.
采用酶解技术对马氏珠母贝肉进行水解,水解率可以达到66.2%。水解液经浓缩、调配、喷雾干燥制成风味独特、营养丰富的马氏珠母贝肉干粉,可广泛应用于调味料生产。  相似文献   

6.
以马氏珠母贝肉为研究对象,采用正交实验对其酶解条件进行优化,并测定其酶解产物对SD大鼠血清生化指标的影响。结果表明:马氏珠母贝肉酶解的最优条件是酶用量0.6%、温度70℃、时间35min、pH8.0,在此条件下马氏珠母贝肉蛋白质水解度高达54.79%。马氏珠母贝肉酶解产物的调配试剂注射使SD大鼠血清中前白蛋白、载脂蛋白A1显著上升(p<0.05),谷丙转氨酶、谷草转氨酶、载脂蛋白B、肌酸激酶MB型同工酶、超敏C反应蛋白、葡萄糖、间接胆红素显著下降(p<0.05),结合相关研究结果,推测出马氏珠母贝肉酶解产物有保肝、保心血管的功效。  相似文献   

7.
分别用碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、胃蛋白酶和胰蛋白酶制备山杏仁蛋白酶水解物,通过格里斯实验和ELISA方法,研究山杏仁蛋白酶水解物对巨噬细胞产生炎症因子NO、TNF-α和IL-1β的影响。结果表明山杏仁木瓜蛋白酶水解物显著抑制炎症因子NO、TNF-α和IL-1β产生,其抑制率分别为62%、11%和21%,而其它四种蛋白酶水解物没有显示明显的抗炎作用。将山杏仁木瓜蛋白酶水解物分离制备为5~10,3~5,1~3 kDa和小于1 kDa等不同分子量组分,进一步研究其抗炎活性,结果表明小于1 kDa低分子量组分具有较高抗炎活性,其对NO、TNF-α和IL-1β产生的抑制率分别为81%、59%和46%。分析氨基酸组成与含量结果表明,抗炎活性较强的小于1 kDa组分中,疏水性氨基酸和亲水性氨基酸含量均较高,同时谷氨酸、天冬氨酸和精氨酸等具有抗炎作用的氨基酸含量也较高。以上结果表明,山杏仁蛋白被木瓜蛋白酶水解后能够释放抗炎生物活性肽,该活性肽的分子量小于1 kDa,可能是具有两亲性的结构。  相似文献   

8.
研究蒙古口蘑多糖提取物对脂多糖(LPS)诱导小鼠单核巨噬细胞(RAW264.7细胞)炎症保护作用的机理。用不同预量质量浓度的蒙古口蘑多糖处理RAW264.7细胞,通过CCK-8法检测细胞活性;Griess法测定NO的产生量;酶联免疫吸附测定肿瘤坏死因子-α(TNF-α),白介素1β(IL-1β);实时定量检测缺氧诱导因子1α(HIF-1α)、诱导型一氧化氮和酶(iNOS)、核因子κB(NF-κB)、信号转导和转录激活因子3(STAT3)和环氧化酶2(COX-2)的mRNA表达量;免疫印迹检测HIF-1α、NF-κB、STAT3和COX-2蛋白质的表达量。结果表明,蒙古口蘑多糖提取物作用RAW264.7细胞的最大剂量为100μg/mL;与LPS模型组相比,蒙古口蘑多糖提取物质量浓度0.01、0.1、1、10μg/mL均能有效抑制NO(抑制率分别是38.21%、64.17%、58.16%和79.42%)、TNF-α(抑制率分别为27.91%、36.31%、36.14%、45.09%)和IL-1β(抑制率分别为47.75%、58.47%、60.21%、64.55%)的产生;在质量浓度为10μg/mL的蒙古口蘑多糖提取物作用下,除NF-κB外,HIF-1α、STAT3、COX-2和iNOS的mRNA的表达量均降低;免疫印迹的结果也显示,除NF-κB外,HIF-1α、NF-κB、STAT3及COX-2的蛋白质的表达量均有不同程度的降低。蒙古口蘑多糖提取物对脂多糖(LPS)诱导的RAW264.7细胞具有保护作用,其抗炎的机制主要通过JAK-STAT3及HIF-1α信号通路,而不主要通过NF-κB信号通路发挥作用。  相似文献   

9.
为探讨高核苷酸酵母水解物对RAW264.7小鼠巨噬细胞免疫活性调节及其相关作用机制,采用脂多糖(1μg/mL)刺激RAW264.7细胞来建立体外细胞炎症模型,以不同质量浓度的高核苷酸酵母水解物干预来明确其抗炎效果。ELISA法检测细胞培养上清中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)的含量,RT-PCR法检测相关mRNA表达水平,Western blot法检测细胞iNOS及胞核内核转录因子NF-κBp65蛋白水平。结果表明:高核苷酸酵母水解物作用RAW264.7细胞的安全范围≤150μg/mL。与LPS模型组相比,质量浓度60~150μg/mL的高核苷酸酵母水解物能显著增强RAW264.7吞噬能力,高核苷酸酵母水解物(60~150μg/mL)能有效抑制脂多糖(lipopolysaccharide,LPS)诱导RAW264.7细胞释放NO、TNF-α、IL-1β和IL-6炎症因子及相关mRNA表达,降低iNOS及NF-κB蛋白水平。研究结果证实了高核苷酸酵母水解物对LPS刺激RAW264.7细胞炎症的保护作用,作用机制与NF-κB通路有关,为食疗干预慢性病提供一定的理论依据。  相似文献   

10.
该研究以商业菌株鼠李糖乳杆菌(Lactobacillus rhamnosus)LGG为阳性对照菌,体外评估实验室保藏的5株乳杆菌对巨噬细胞RAW264.7细胞活性、吞噬活性及免疫活性分子NO、肿瘤坏死因子-α(TNF-α)与白细胞介素-10(IL-10)分泌水平的影响,以期从中筛选出具良好免疫调节作用的菌株。结果表明,鼠李糖乳杆菌260具有更优的免疫调节作用,在特定乳杆菌活菌浓度时,能显著提高巨噬细胞RAW264.7的细胞活性、吞噬活性及NO、TNF-α和IL-10的分泌水平(P<0.05)。最高细胞增殖率为196.62%;最低乳酸脱氢酶(LDH)释放量为554.36 U/100 mL;最高吞噬活性为136.86%;最高NO分泌量为5.70 μmol/L;最高IL-10分泌量为15.56 pg/mL,最高TNF-α分泌量为50.98 pg/mL。  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   

15.
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.  相似文献   

16.
17.
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.  相似文献   

18.
19.
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   

20.
<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   

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