葛仙米藻胆蛋白提高小鼠免疫功能的研究

研究葛仙米藻胆蛋白对昆明小鼠的免疫增强活性。分别以100、300、500 mg/（kg·d）的葛仙米藻胆蛋白溶液剂量对小鼠连续灌胃30 d。然后分别对腹腔巨噬细胞吞噬率、自然杀伤（natural killer,NK）细胞活性,T淋巴细胞增殖、细胞因子、抗体、迟发型超敏反应（delayed type hypersensitivity,DTH）等免疫参数进行测定。结果表明：葛仙米藻胆蛋白可以提高腹腔巨噬细胞吞噬率、NK细胞活性、T淋巴系统增殖以及血清中白细胞介素（interleukin-2,IL-2）和IL-4细胞因子水平。同时葛仙米藻胆蛋白处理组的小鼠DTH显著高于对照组,表明葛仙米藻胆蛋白是一种潜在的免疫增强剂。     

江蓠藻膳食纤维对衰老小鼠免疫功能与抗氧化作用的影响

目的:研究江蓠藻膳食纤维对衰老模型小鼠免疫功能及抗氧化作用的影响.方法:小鼠随机分为空白对照组、模型对照组、燕麦膳食纤维组(400mg/kg体重)及江蓠藻膳食纤维高、中、低剂量组(800、400、200mg/kg体重).在给药的同时,除空白对照组外,其余各组小鼠每天颈背皮下注射10%D-半乳糖0.25mL,连续给药40d后,测定迟发性变态反应(DTH),腹腔巨噬细胞吞噬功能,胸腺、脾脏系数,血清及脾脏中超氧化物岐化酶(SOD)的活性、过氧化氢酶(CAT)及丙二醛(MDA)的含量.结果:江蓠藻膳食纤维能够明显促进迟发型超敏反应的发生,增强巨噬细胞的吞噬能力,提高脾脏和胸腺的脏器系数,激活小鼠血清及脾脏中抗氧化酶的活性,降低MDA的含量.结论:江蓠藻膳食纤维可增强衰老小鼠的免疫功能.     

白扁豆多糖对正常小鼠体内抗氧化和免疫实验研究

采用正常小鼠进行体内抗氧化和免疫实验,通过测定小鼠血清中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)的活力,来评价其抗氧化能力;通过观察正常小鼠腹腔巨噬细胞吞噬功能和小鼠血清溶血素形成的影响,来评价其免疫活性。结果表明,白扁豆多糖可使SOD、GSH-Px活力升高,可显著提高正常小鼠腹腔巨噬细胞的吞噬百分率和吞噬指数,促进溶血素形成。     

葛仙米藻胆蛋白粗提物、藻蓝蛋白和藻红蛋白的体外抗氧化活性比较研究

在体外模型上,对人工养殖的葛仙米藻胆蛋白粗提物、藻蓝蛋白和藻红蛋白的抗氧化活性进行比较研究。通过考察羟基自由基清除能力、超氧阴离子自由基清除能力、脂质过氧化抑制能力,对葛仙米中藻胆蛋白粗提物、藻蓝蛋白和藻红蛋白的抗氧化活性进行评价。体外抗氧化作用结果显示藻胆蛋白、藻红蛋白和藻蓝蛋白都有明显的抗氧化作用,但作用方式和抗氧化程度也有不同,在羟基自由基清除试验中,抗氧化活性由强到弱依次为藻胆蛋白藻蓝蛋白藻红蛋白;在超氧阴离子清除试验中藻红蛋白≧藻蓝蛋白藻胆蛋白;在抑制脂质过氧化试验中藻红蛋白藻胆蛋白藻蓝蛋白。人工养殖的葛仙米中藻蓝蛋白、藻红蛋白及藻胆蛋白粗提物具有很好的体外抗氧化活性,但三者抗氧化方式略有差异。     

藤本豆豆荚总黄酮对小鼠免疫功能的影响

研究藤本豆豆荚总黄酮对正常小鼠免疫功能及体内抗氧化活性的影响。以小鼠免疫器官系数、脾淋巴细胞增殖活性、巨噬细胞吞噬能力、细胞因子水平、血清SOD、GSH-Px和MDA为指标评价藤本豆豆荚总黄酮的免疫功能和体内抗氧化活性。结果表明,与阴性对照组比较,灌胃给予正常小鼠藤本豆豆荚总黄酮30d后,小鼠胸腺系数和脾脏系数分别增加12.34%和8.67%,小鼠脾脏淋巴细胞的增殖活性和巨噬细胞的吞噬能力分别增加114.68%和27.16%,小鼠血清IFN-γ、AKP、SOD和GSH-Px的活性分别提高8.25%,82.52%,10.47%,12.16%,血清MDA水平降低32.97%。藤本豆豆荚总黄酮具有增强正常小鼠免疫功能和体内抗氧化活性的作用。     

红茶多酚对H22荷瘤小鼠的免疫调节和抗氧化作用

本试验以从坦洋工夫红茶中提取的茶多酚为原料,研究其对H22荷瘤小鼠的免疫调节和抗氧化作用。对实验动物灌胃不同剂量的红茶多酚[250 mg/(kg·d)和500 mg/(kg·d)]14 d后,腋下接种H22细胞构建肿瘤模型,并继续灌胃21 d,然后通过MTT法检测各组小鼠脾脏中淋巴细胞增殖能力和NK细胞活性,以中性红为指标检测其腹腔巨噬细胞吞噬能力,流式细胞术确定其血液中淋巴细胞亚群分布,同时采用试剂盒检测小鼠血清中白细胞介素-2(IL-2)、干扰素-γ(IFN-γ)、肿瘤坏死因子-α(TNF-α)的水平和肝脏组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活力以及丙二醛(MDA)的含量。结果表明,红茶多酚可显著抑制体内肿瘤的生长,实验期结束时低剂量组和高剂量组的抑瘤率分别达到46.04%和63.32%。与模型组相比,红茶多酚可有效保护荷瘤小鼠的脾脏和胸腺,显著增强其脾淋巴细胞的增殖能力和NK细胞的杀伤活性(P0.05),并显著提高腹腔巨噬细胞的吞噬能力、外周血T淋巴细胞的比例以及血清中IL-2、IFN-γ、TNF-α的水平(P0.05),同时红茶多酚可使小鼠肝脏组织中的SOD、GSH-Px活力升高,MDA含量降低(P0.05)。红茶多酚具有良好的抗肿瘤作用,其机制可能与增强机体的免疫调节活性,提高抗氧化能力有关。     

桦褐孔菌水提物免疫活性的研究

研究桦褐孔菌水提物对免疫低下BALB/c小鼠的免疫调节作用。方法:72只BALB/c小鼠按体重随机分为6组(n=12),各组分别为:正常实验组、模型对照组、阳性对照组、桦褐孔菌水提物低剂量组、中剂量组、高剂量组;通过小鼠腹腔注射环磷酰胺的方式,建立免疫缺陷模型,饲养13天后,断颈处死,评价小鼠体重、脾脏指数、胸腺指数、NK细胞杀伤活性、腹腔巨噬细胞吞噬能力、脾脏淋巴细胞的增殖能力、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)、丙二醛(MDA)、总抗氧化能力(T-AOC)、过氧化氢酶(CAT)、碱性磷酸酶(AKP)等含量的变化情况,考察桦褐孔菌水提物的免疫调节作用。结果表明:桦褐孔菌水提物剂量组与模型组比较,剂量组500mg/kg、1000mg/kg、2000mg/kg对环磷酰胺致免疫低下小鼠的体重和脏器指数都有显著的提高作用,能明显增强小鼠腹腔巨噬细胞的吞噬能力,促进脾脏淋巴细胞的增殖能力,显著的提高NK细胞的杀伤活性;提高免疫低下小鼠肝脏和血清中的GSH-Px、SOD、CAT、AKP等酶的活性,从而提高免疫低下小鼠的免疫功能。     

富硒青钱柳-黄精复方茶饮对小鼠的免疫调节作用

目的 从细胞免疫、体液免疫、单核-巨噬细胞功能、NK细胞活性四个方面研究富硒青钱柳-黄精复方对正常小鼠免疫功能的影响。方法 C57BL/6正常小鼠随机分为对照组、阳药组、富硒青钱柳复方低中高剂量组,灌胃给药30 d后,分别测定小鼠体质量、胸腺和脾脏指数、淋巴细胞增殖转化能力、腹腔巨噬细胞吞噬鸡红细胞能力、NK细胞活性及血清溶血素(HC50)水平等免疫学指标。结果 富硒青钱柳-黄精复方对小鼠体质量没有明显影响,高中低剂量均可提高淋巴细胞增殖刺激指数、腹腔巨噬细胞吞噬百分率及吞噬指数(P < 0.05或P < 0.01),中剂量可显著提高胸腺指数及NK细胞活性(P < 0.01),低剂量可显著提高HC50(P < 0.01)。结论 富硒青钱柳-黄精复方可显著增强正常小鼠的免疫功能。     

白首乌总甙对小鼠免疫功能的影响

研究了白首乌总甙对小鼠免疫器官称重的影响,对小鼠腹腔巨噬细胞(MΦ)的形态、吞噬消化功能、酸性磷酸酶(Acpase)活性以及与同体胸腺细胞结合的能力等指标进行了研究.结果表明,白首乌总甙对小鼠免疫器官的称重没有影响;能激活小鼠腹腔MΦ,显著提高其吞噬消化功能,从而提高小鼠的非特异性免疫力;能显著提高MΦ提呈抗原的能力,从而提高机体的特异性免疫作用.     

松针提取物抗衰老氧化作用研究

目的观察松针的抗衰老作用。方法玉米须粗多糖按100、200、400mg/kg连续灌胃3～7d,观察小鼠的存活时间,连续游泳时间和免疫器官重量试验。大鼠连续灌胃20d,测血清LPO含量和SOD活性。结果松针能明显提高小鼠耐氧及抗疲劳能力,增加正常小鼠免疫器官重量,并明显增强小鼠网状内皮系统的吞噬功能。可明显降低老年大鼠血清过氧化脂质(LPO)含量,提高超氧化物歧化酶(SOD)活性。结论松针具有抗衰老作用。     

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.     

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.     

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.     

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.     

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.