膳食5’-核苷酸对酒精性肝损伤大鼠肠道菌群的影响

目的:研究膳食5’-核苷酸对酒精性肝损伤大鼠肠道菌群的影响,并进一步探讨可能的作用机制。方法:雄性Wistar大鼠随机分为对照组、酒精组、葡萄糖等热量对照组、普通饲料组、质量分数0.04%、0.16%5’-核苷酸干预组,连续饲养7周,测定大鼠体质量、脏体比、血清乙醇体积分数、血清转氨酶活力、血脂水平及总蛋白含量等相关指标;平板培养大鼠粪便中的乳酸杆菌、双歧杆菌、大肠杆菌、肠球菌,计算大鼠粪便中各种细菌的菌落数。结果:膳食5’-核苷酸能够增加酒精引起的大鼠体质量降低,轻度抑制血清乙醇体积分数的升高,抑制酒精引起丙氨酸氨基转移酶、乳酸脱氢酶活力和甘油三酯水平等升高(P0.05),增加血清总蛋白、白蛋白及球蛋白含量(P0.05);并能够增加肝体比,减少盲体比(P0.05);膳食5’-核苷酸能够增加肠道乳酸杆菌数量,同时减少大肠杆菌及肠球菌的数量(P0.05)。结论:膳食5’-核苷酸能够改善酒精引起的大鼠肝脏损伤,调节肠道菌群可能是其作用机制之一。     

5'-核苷酸对慢性酒精中毒诱导大鼠结肠功能损伤的影响

探讨外源性5'-核苷酸对酒精诱导大鼠结肠功能紊乱的保护作用。50只SPF级雄性Wistar大鼠随机分为正常对照组、酒精模型组、等热量对照组及0.04%、0.16%核苷酸组。连续酒精灌胃6周后,结果发现,外源性5'-核苷酸能够有效改善酒精引起的大鼠结肠病理性改变,显著提高结肠功能相关蛋白Claudin和Occludin的表达水平(p0.01或p0.05),极显著降低大鼠结肠组织中Toll样受体4(TLR4)和分化抗原簇14(CD14)的表达水平(p0.01);外源性5'-核苷酸能够显著增加大鼠回肠内容物中双歧杆菌(酒精组8.00 log CFU/g,核苷酸组8.32 log CFU/g)和乳酸杆菌数量(酒精组7.44 log CFU/g,核苷酸组8.13 log CFU/g)(p0.05),同时显著减少肠球菌(酒精组7.52 log CFU/g,核苷酸组7.03 log CFU/g)及大肠杆菌数量(酒精组6.85 log CFU/g,核苷酸组6.19 log CFU/g)(p0.05)。因此,外源性5'-核苷酸能够通过调节肠道菌群改善酒精引起的大鼠结肠损伤。     

L-阿拉伯糖对正常及高糖高脂喂养大鼠生长及糖脂代谢的影响

目的观察L-阿拉伯糖对正常大鼠和高糖高脂喂养大鼠生长及糖脂代谢的影响。方法雄性Wistar大鼠60只,按体重和空腹血糖随机分为6组(n=10):空白对照组、高剂量对照组、模型对照组以及L-阿拉伯糖低、中、高剂量实验组,分别以普通饲料和高糖高脂饲料喂养6周,观察大鼠的体重、食物利用率,测定大鼠的糖脂代谢指标。结果L-阿拉伯糖对正常大鼠的体重、体脂、食物利用率、空腹血糖均无影响;能显著提高正常大鼠的糖耐量(P<0.01);降低正常大鼠的血清甘油三酯(P<0.05)并增高血清高密度脂蛋白胆固醇(P<0.01)。模型对照组和各实验组大鼠的体重、体脂、糖耐量、血清总胆固醇均显著高于空白对照组(P<0.05)。以87.5、175、525mg/kgBW剂量的L-阿拉伯糖灌胃高糖高脂饲料喂养的肥胖模型大鼠6周,各剂量L-阿拉伯糖均能显著改善肥胖模型大鼠的糖耐量(P<0.01),高剂量组大鼠的体脂含量明显下降(P<0.05)。结论L-阿拉伯糖能显著增强正常和高糖高脂喂养大鼠的糖耐量,降低大鼠血清甘油三酯,增高血清高密度脂蛋白胆固醇,并有降低大鼠体脂含量和减缓体重增加的趋势。     

乳糖饮水对Sprague-Dawley大鼠糖、脂、尿酸代谢的影响

目的：探讨不同质量浓度乳糖饮水对Sprague-Dawley（SD）大鼠糖、脂、尿酸代谢的影响。方法：分别以清水,50、100、150 g/L乳糖水饲喂大鼠8 周,观察不同时间点大鼠的能量摄入及体质量等一般状态指标。取大鼠血清检测血糖（glucose,GLU）、尿酸（uric acid,UA）、甘油三酯（triglyceride,TG）、总胆固醇（totalcholesterol,TC）、高密度脂蛋白胆固醇（high density lipoprotein cholesterol,HDL-C）、低密度脂蛋白胆固醇（low density lipoprotein cholesterol,LDL-C）水平。结果：与正常组相比,150 g/L乳糖组大鼠的能量摄入显著降低,且于实验第1、2周体质量显著降低（P＜0.05）。各剂量乳糖组大鼠的GLU水平均高于正常组（P＜0.05或P＜0.01）。50、100 g/L乳糖组大鼠的UA水平低于正常组（P＜0.05或P＜0.01）,150 g/L乳糖组大鼠的UA水平于第1周一次性升高（P＜0.05）。100 g/L乳糖组大鼠的TG水平于第6周显著升高（P＜0.05）,150 g/L乳糖组大鼠的TG水平于第1～3周显著升高且TC水平于第2、3、7周显著升高（P＜0.05或P＜0.01）。乳糖组大鼠的LDL-C水平均显著或极显著升高（P＜0.05或P＜0.01）。结论：不同质量浓度乳糖摄入可对大鼠血糖、血脂、尿酸代谢产生不同影响,使用时应控制乳糖适宜的摄入剂量。     

食用白酒对大鼠血压的影响

研究食用白酒对大鼠血压的影响。将32只健康成年雄性SD大鼠随机分为酒样1组、酒样2组、酒样3组和生理盐水对照组。各酒样组大鼠分别给予相应的酒样5 mL/kg·d,对照组给予等体积量的生理盐水灌胃。每天上午9:00、下午18:00各灌胃1次,上午和下午的灌胃剂量均为当天灌胃总量的一半。灌胃12周后,各组大鼠分别先后用尾套法和颈总动脉插管法测其血压。结果表明,各酒样组大鼠收缩压值略高于生理盐水对照组大鼠,但无统计学差异(P0.05);各酒样组间大鼠收缩压值无明显差异(P0.05);饮用3种52%vol食用白酒(5 mL/kg·d)12周可使大鼠血压略升高,但是血压升高不显著。     

探究复配蓝莓提取物叶黄素制剂的急性及长期毒性

目的：本文研究了蓝莓提取物叶黄素对大鼠、小鼠的急性毒性经口试验及大鼠的30 d喂养试验。方法：急毒试验采用最大剂量耐受法,复配蓝莓提取物叶黄素制剂(以下简称试样)的人(以60 kg计)推荐量为16.67 mg·(kg bw·d)^-1,采用经口灌胃给试样方式,按20 g·(kg bw)^-1剂量分两次给予试样。30 d喂养试验设3个试样剂量组和空白对照组,高、中、低3个剂量分别为1.67 g·(kg bw)^-1、0.83 g·(kg bw)^-1、0.42 g·(kg bw)^-1,相当于人推荐量的100倍、50倍和25倍。结果：在急性毒性经口试验中,大鼠、小鼠体重均增加,均无死亡情况和中毒症状。在大鼠的30 d喂养试验中,其体重、周进食量及总食物利用率、周食物利用率、大鼠血液学、血液生化指标、大鼠脏体比等指标与对照组比较,p> 0.05,均无显著性意义。大鼠组织病理学观察中均未观察到有异常现象。结论：蓝莓提取物叶黄素经口最大耐受剂量大于20 g·(kg bw)^-1     

β-葡聚糖生物强化大米28天经口毒性研究

目的 通过28 d经口毒性试验研究,对β-葡聚糖生物强化大米的安全性进行评价。方法 将断乳SD大鼠随机分为对照组和低、中、高剂量组(2.5、5.0和10.0 g/kg BW),每组22只,雌雄各半。按照10 mL/kg BW经口灌胃,连续给予28 d,实验前后对大鼠进行眼部检查,处死动物后进行尿常规、血液学、血生化、脏器系数测定及组织病理学检查。结果 与对照组相比,给药组动物外观、体质量、食物利用率、脏器系数、血生化和尿常规检测均没有明显差异;雄性中、高剂量组和雌性高剂量组在第4周的进食量与对照组相比具有统计学差异(P<0.05或P<0.01),但均无时间上的延续性,认为无毒理学意义;雄性中、高剂量组的血小板含量与对照组相比具有统计学差异(P<0.05),但无剂量-反应关系,仅限单个指标异常,且均在实验室参考值范围之内,认为不具有毒理学意义;高剂量组病理学检查未见与受试物有关的病理性改变。结论 在本试验条件下,SD大鼠短期经口摄入β-葡聚糖生物强化大米未见毒性作用,但长期食用的安全性尚需进一步研究。     

曲酸对动物的毒性研究及安全性评价

目的:研究曲酸对动物的毒性作用及安全性评价。方法:急性毒性实验、105d喂养实验。结果:曲酸对小鼠有明显的急性毒性作用,LD50为2571mg/kgbw,在105d大鼠喂养实验中,曲酸对大鼠生长发育、总食物利用率、血液生化指标、多个脏器的脏器系数,以及部分血液指标均无显著影响,但曲酸使雌、雄鼠白细胞数、淋巴细胞数明显下降,中性粒细胞数明显增加,各剂量组之间有剂量-效应关系,T3、T4有下降趋势,500mg/kgbw组少数动物出现了睪丸发育不良、甲状腺间质增生、肾脏和肝脏部分病理改变。结论:曲酸属低毒物质,长期高剂量使用可能会影响实验动物的生长发育及器官的结构和功能改变。     

脱脂大米胚芽降脂减肥作用研究

目的:探讨脱脂大米胚芽对大鼠肥胖及高血脂的预防性作用。方法:将50只大鼠按血清总胆固醇(TC)水平随机分为阴性对照组、肥胖模型组和3个添加不同剂量的脱脂大米胚芽组20、100、300mg/kgbw。每周称重1次,第5周末断头取血,测TC、TG和HDL-C;剥离肾及睾丸周围脂肪并称重。结果:肥胖模型组与阴性对照组相比,大鼠体重、体脂比、TC、TG水平显著增加;3个脱脂大米胚芽添加组大鼠体重、体脂比、TC、TG水平均低于肥胖模型组,且有显著性或极显著性差异。结论:脱脂大米胚芽能够预防大鼠肥胖及高脂血症的形成。     

黄秋葵水提物对2型糖尿病大鼠糖脂代谢的影响

目的:探索黄秋葵水提物对2型糖尿病大鼠糖、脂代谢的影响。方法:将雄性SD大鼠按体重随机分为正常对照组和实验组,分别饲以普通饲料和高糖高脂饲料。4周后,实验组大鼠腹腔注射链脲佐菌素(STZ)建立2型糖尿病模型,之后按血糖随机分为模型组、阳性对照组(0.64 g/kg降糖宁混悬液灌胃)、黄秋葵水提物高、中、低剂量组(分别以2.60、1.56、0.78 g/kg黄秋葵冻干粉添加到饲料中),持续4周。记录大鼠体重、摄食量、饮水量、尿量,检测空腹血糖及总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)。结果:黄秋葵高剂量组血糖低于模型组和低剂量组(p0.05,p0.05);黄秋葵各剂量组的TC值显著低于模型组(p0.01);高剂量组LDL-C低于模型组(p0.01)。结论:黄秋葵水提物能显著降低2型糖尿病大鼠的血糖和血脂水平。     

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