黄鳍金枪鱼头蛋白酶解液及其分级组分对小鼠免疫功能的影响

研究黄鳍金枪鱼头蛋白酶解液(EPTH)及其截留相对分子质量(MWCO)10 000和5 000超滤膜的分级组分Ⅰ(10 000)、组分Ⅱ(5 000～10 000)与组分Ⅲ(<5 000)对小鼠免疫功能的影响.采用灌胃给药,每天1次,分别于第14、19、32及35天测定有关免疫功能指标.结果表明:组分Ⅱ显著提高小鼠胸腺指数、脾脏指数、廓清指数,显著促进小鼠脾细胞抗体形成功能,提高骨髓细胞DNA含量,对小鼠淋巴细胞转化能力无显著影响;EPTH显著提高小鼠骨髓细胞DNA含量;组分Ⅰ、组分Ⅲ显著提高小鼠脾脏指数.组分Ⅱ富集了更多的免疫活性物质,具有增强小鼠免疫功能的作用.     

黄豆芽多糖对免疫抑制小鼠的实验研究

目的:研究黄豆芽多糖(BSPS)对免疫功能低下小鼠的免疫调节作用.方法:采用药物、荷瘤的方法建立免疫抑制小鼠动物模型,利用MTT方法、淋巴细胞转化及巨噬细胞吞噬中性红实验,检测黄豆芽多糖对免疫抑制小鼠免疫反应的影响.结果:黄豆芽多糖可增强吞噬细胞的吞噬功能,增加抗体形成细胞的数量,促进淋巴细胞转化.证明黄豆芽多糖具有增强小鼠免疫功能的作用.     

复合乳酸菌粉冲剂增强免疫力作用的研究

研究了复合乳酸菌粉((嗜酸乳杆菌+乳双歧杆菌+低聚木糖)的益生菌冲剂在增强儿童免疫力方面的作用,研究方法依照《保健食品检验与评价技术规范》(2003版)之"增强免疫力功能检验方法"。结果表明:对SPF级昆明种小鼠经口每日分别给予该复合益生菌产品0.25、0.50、1.50 g/kg.BW,相当于人推荐日服量的5、10、30倍共4周,实验显示:绵羊红细胞诱导的小鼠迟发型变态反应试验和ConA诱导的小鼠脾淋巴细胞转化增殖试验结果呈阳性,说明该样品具有增强细胞免疫功能作用(P<0.05);同时受试动物NK细胞活性试验结果呈阳性,说明该样品具有显著增强NK细胞活性作用(P<0.01)。实验证明摄入该复合益生菌产品具有增强免疫力的功能作用。     

羊肚菌胞外多糖抗肿瘤作用的研究

目的：研究羊肚菌胞外多糖（EPM）对S180荷瘤小鼠的抗肿瘤作用与免疫功能的影响。方法：将昆明种小鼠接种S180腹水瘤后随机分组,灌胃给予200、400mg／kg剂量的EPM,以灌胃生理盐水和环磷酰胺为空白对照组和阳性对照组,研究EPM对荷瘤小鼠的抑瘤率、存活期和免疫功能的影响;通过与肿瘤细胞共培养,观察EPM对肿瘤细胞增殖的影响。结果：EPM能够显著提高荷瘤小鼠的脾脏指数、T．淋巴细胞百分率和巨噬细胞吞噬率;2个剂量的EPM对肿瘤8180的抑制率分别为49．04％和64．42％,并且可以显著延长荷瘤小鼠的存活时间;体外实验发现羊肚菌多糖EPM具有直接杀死S180肿瘤细胞的作用,最高抑制率为46．3％,结论：MEP具有显著的抗肿瘤活性和增强免疫功能。     

甘薯叶柄藤多糖的免疫调节作用研究

研究薯蔓多糖(PSPV)对动物的非特异性免疫和特异性体液免疫调节作用。采用碳粒廓清实验研究PSPV对正常和免疫低下小鼠的非特异性免疫功能;血清溶血素测定法研究PSPV的特异性体液免疫功能。结果表明:PSPV可提高正常和免疫低下小鼠的廓清指数K和呑噬指数α,800mg／kg剂量的PSPV可显著提高小鼠血清的血清溶血素HC50。结论:PSPV具有促进单核巨噬细胞系统吞噬功能的作用,可增强小鼠的非特异性免疫功能,同时也可极显著地增强小鼠的特异性体液免疫功能。     

不同发酵天数的芝芪菌质对免疫抑制小鼠免疫功能的影响

为筛选较佳的芝芪菌质发酵时间,本实验通过小鼠碳粒廓清实验,鸡红细胞吞噬功能实验,小鼠血清溶血素、Ig M和Ig G的含量检测,以及小鼠脾淋巴细胞增殖实验,考察了不同发酵天数的芝芪菌质对免疫抑制小鼠非特异性和特异性免疫功能的影响。结果表明:发酵25、30 d的芝芪菌质具有显著的免疫增强功效(p0.05,0.01;0.05),提示可有效增强免疫功能低下人群的机体免疫力。     

大豆肽免疫调节作用的研究

目的:研究大豆肽对正常及免疫低下小鼠免疫功能的影响。方法:腹腔注射环磷酰胺以引起小鼠免疫功能低下,观察大豆肽对正常及免疫功能低下小鼠胸腺指数、脾脏指数、脾淋巴细胞对ConA的刺激指数(SI)、抗体生成细胞含量(PFC)和血清溶血素(HC50)等指标的影响。结果:大豆肽不仅能增强正常小鼠免疫功能,而且能显著提高环磷酰胺致免疫功能低下小鼠的胸腺指数、脾脏指数、脾淋巴细胞对ConA的刺激指数、抗体生成细胞含量和血清溶血素的含量。结论:大豆肽对机体的免疫功能有一定的增强作用。     

高活性大豆肽增强免疫及减肥作用的研究

目的:研究高活性大豆肽对免疫功能的调节作用及对营养性肥胖的预防作用。方法:测定高活性大豆肽剂量组动物的细胞免疫和体液免疫两项功能,综合考察高活性大豆肽的免疫功能。建立大鼠高脂肥胖模型,高活性大豆肽灌胃,以大鼠体重、脂/体比为标准,观察高活性大豆肽的预防肥胖作用。结果提示:高活性大豆肽剂量组动物的迟发型变态反应试验、小鼠半数溶血值测定实验、小鼠巨噬细胞吞噬鸡红细胞试验及自然杀伤细胞(NK cell)活性测定实验均有显著增强作用,说明高活性大豆肽对实验小鼠的机体具有免疫增强作用。高活性大豆肽剂量组动物的平均体重及体脂均显著低于肥胖模型组,说明高活性大豆肽对实验大鼠具有减肥作用。     

两种灵芝多糖对小鼠免疫功能增强作用研

研究两种不同工艺提取的灵芝多糖-超声提取多糖(UCP)和碱提多糖(ACP)对小鼠免疫功能的增强作用。实验小鼠分别按低、中、高剂量胃饲两种灵芝多糖提取物,测试其对小鼠免疫功能的影响(小鼠碳廓清实验、迟发性变态反应、血清溶血素测定、NK细胞活性实验)。结果表明,各剂量组的UCP和ACP血清溶血素含量,ACP各剂量和UCP高剂量组的小鼠迟发型变态反应(DTH),高剂量组的ACP小鼠碳廓清能力,高剂量组UCP和ACP中、高剂量的小鼠NK细胞活性,UCP低剂量组的小鼠胸腺指数,与对照组比较均有显著性差异(p<0.05)。说明两种灵芝多糖均能提高小鼠的免疫功能,ACP的作用优于UCP,且灵芝多糖对小鼠免疫功能的增强作用并不是剂量越大越好,而是存在最适剂量。     

鲜驴奶的保健功效研究

目的:研究鲜驴奶对小鼠免疫功能的影响;及鲜驴奶体外抑制结核杆菌生长作用.方法:应用环磷酰胺制备免疫低下小鼠模型,以不同剂量鲜驴奶作为受试物灌胃20d,研究鲜驴奶对小鼠脾脏及胸腺指数、抗体分泌细胞功能、血清溶血素水平、脾脏淋巴细胞转化功能等免疫指标的影响;按照<结核病诊断细菌学检验规程>以覆盖法研究鲜驴奶体外抑制结核杆菌生长作用.结果:鲜驴奶高剂量组可以增加血清溶血素含量并可提高小鼠脾细胞抗体分泌细胞功能;大剂量 (0.4、0.5ml)驴奶脂肪抑菌效果明显.结论:鲜驴奶对免疫力低下小鼠的免疫功能具有一定的增强作用;鲜驴奶脂肪在体外具有抑制结核杆菌生长的作用.     

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.     

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.     

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.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.