辣椒素剂量对去势雌性大鼠血脂、肝脂及盲肠内环境的影响

目的：探讨辣椒素剂量对去势雌性大鼠血脂、肝脂及盲肠内环境的影响。方法：选用30 只雌性SD大鼠随机分组为5 组,其中1 组大鼠进行伪切除手术作对照（伪切除组）,另外4 组大鼠做双侧卵巢切除手术,基础饲料喂养恢复1 周后,分为不灌胃辣椒素（空白组）和灌胃5.0、10.0、15.0 mg/（kg·d）辣椒素剂量组（低、中、高剂量组）。喂食相同基础饲料28 d后解剖,测定大鼠血清和肝脏中胆固醇、甘油三酯含量及盲肠面积,盲肠内容物水分含量、pH值、短链脂肪酸和微生物等指标。结果：空白组大鼠的体质量、采食量、血脂、肝脏总脂肪、总胆固醇、甘油三酯总含量均显著高于伪切除组。辣椒素可降低双侧卵巢切除大鼠的体质量增加量、血清和肝脏中胆固醇和甘油三酯含量,且具有明显的剂量关系;同时可以降低盲肠组织总质量、盲肠体质量比、盲肠内容物短链脂肪酸含量,显著降低盲肠内容物有益菌数量（P＜0.05）;辣椒素可以显著升高游离氨含量和pH值,增加有害菌数量（P＜0.05）,但辣椒素各剂量组之间没有显著性差异。结论：辣椒素对因雌激素缺乏引起高脂血症雌性大鼠具有较好的降血脂、降肝脂作用,但对盲肠内环境具有一定的损伤作用。     

薛荔籽果胶对去势雌性大鼠矿物质吸收的影响

目的:探讨薛荔籽果胶对去势雌性大鼠矿物质吸收的影响。方法:将30只SD成年雌鼠随机分为5组。4组大鼠做双侧卵巢切除手术,一周后分为空白组和薛荔籽果胶高、中、低剂量组;用伪切除同龄大鼠作对照(Sham组)。喂养4周后解剖,测定盲肠内容物pH值、短链脂肪酸、骨钙、骨磷含量及矿物质元素的表观吸收等指标。结果:去势雌性大鼠对钙、镁、磷、锌和铁元素的表观吸收率及骨钙和骨磷含量显著低于正常大鼠(P<0.05)。薛荔籽果胶能显著增加去势雌性大鼠短链脂肪酸含量和盲肠面积(P<0.05),降低盲肠pH值,并且在一定程度上抑制钙、镁、磷、锌和铁元素的表观吸收率。结论:薛荔籽果胶能降低去势雌性大鼠矿物质的表观吸收率。     

薛荔籽果胶对高脂膳食去势大鼠脂质代谢及盲肠内环境的影响

目的：研究薛荔籽果胶对高脂膳食去势大鼠脂质代谢及盲肠内环境的影响。方法：将40 只健康雌性Sprague-Dawley（SD）大鼠随机分为5 组,其中1 组作为空白对照进行卵巢伪切除手术（Sham组）,另外4 组进行双侧卵巢切除手术（OVX组）,1 周后分为模型对照组和饲喂5%、10%、15%薛荔籽果胶低、中、高剂量组。喂养4 周后解剖测定大鼠血脂和肝脂含量、肝脏组织形态,以及盲肠内容物含水率和短链脂肪酸（shortchainfatty acids,SCFAs）含量等指标。结果：模型对照组大鼠的血脂以及肝脏质量、肝脏脂肪含量、每克肝脏中胆固醇、甘油三酯含量显著高于双侧卵巢伪切除组（P＜0.05）。薛荔籽果胶对双侧卵巢切除大鼠的血脂浓度几乎没有影响,而肝脏质量有升高趋势,但无显著性差异;同时能显著升高盲肠壁湿质量、盲肠壁表面积、盲肠组织湿质量和盲肠内容物湿质量（P＜0.05）;也能升高盲肠内容物中各SCFAs和总SCFAs含量,且具有明显的剂量关系。结论：薛荔籽果胶对高脂膳食引起高脂血症去势大鼠的血脂、肝脂没有降低效果,反而升高了肝脂水平,但在肠道方面,能改善高脂膳食去势大鼠肠道健康。     

辣椒素对肠道菌体外发酵的影响

食用辣椒会带来肠道不适反应,对肠道环境存在潜在影响.实验拟通过体外发酵验证辣椒素对肠道发酵环境的影响.向大鼠盲肠内容物发酵液中添加0.05％、0.10％、0.15％三种浓度辣椒素,培养10h后检测发酵液中pH、游离氨、短链脂肪酸(SCFA)及双歧杆菌、乳酸杆菌、大肠杆菌3种微生物的变化趋势,探讨辣椒素对肠道发酵环境的影响.结果表明,与空白组相比,添加辣椒素使盲肠内容物发酵液pH、游离氨浓度升高,短链脂肪酸含量降低,双歧杆菌、乳酸杆菌数量下降,而大肠杆菌数量上升.所有变化均与辣椒素添加剂量存在相关性.研究结果表明,辣椒素对肠道发酵环境有潜在危害.     

花椒精非挥发性成分对大鼠肠道健康的影响

目的:研究花椒精中非挥发性组成成分对大鼠肠道健康的影响。方法:4组实验鼠分别被灌胃相同量的大豆油、花椒精去除挥发油成分(RE)、花椒麻味物质(NTC)和花椒精除去以上两部分后的剩余物(REN)的大豆油溶液,4周后处死取样,测定各相关指标。结果:灌胃NTC组盲肠壁面积减小,游离氨浓度显著升高,短链脂肪酸含量无显著变化,盲肠内容物中乳酸菌等有益菌数量减少,大肠杆菌等有害菌数量显著上升;RE组各指标变化趋势与NTC组相同,但没有NTC作用效果显著;灌胃REN组短链脂肪酸浓度显著增大,游离氨浓度显著升高,pH呈下降趋势,盲肠壁面积增大,盲肠内容物中部分有益菌和有害菌数量均有上升趋势。结论:RE和NTC均会抑制大鼠肠道发酵,对肠道健康有害,且NTC的作用强于RE组分。     

辣椒素对糖尿病大鼠肠道健康的影响

目的：研究辣椒素对链脲佐菌素（streptozotocin,STZ）诱导的糖尿病大鼠肠道环境的影响。方法：将40 只Sprague-Dawley（SD）雄性大鼠按体质量随机分为5 组,每组8 只。其中一组为正常对照组（CON组）,其余4 组采用STZ诱导大鼠建立糖尿病模型,分别为模型空白组,辣椒素低（3.0 mg/（kg•d））、中（6.0 mg/（kg•d））、高（9.0 mg/（kg•d））剂量组。实验期间给大鼠喂食基础饲料,自由采食和饮水。饲养28 d后将大鼠处死解剖,测定各组大鼠体质量、盲肠壁表面积、盲肠内容物的水分含量、pH值、游离氨含量以及微生物数量、短链脂肪酸（short-chain fatty acid,SCFA）含量和肠道组织形态等指标。结果：辣椒素使糖尿病大鼠的总游离氨含量、pH值、水分含量均升高,SCFA含量降低,盲肠内容物中有益菌数量降低,有害菌数量显著增加（P＜0.05）。结论：灌胃低、中、高剂量的辣椒素对糖尿病大鼠肠道环境均有一定的损害作用。     

魔芋葡甘低聚糖对大鼠肠道环境的影响

目的：研究以半干法酶解制备的魔芋葡甘低聚糖（konjac oligosaccharides,KOS）对大鼠肠道环境的影响。方法：将KOS掺入到饲料中饲喂Sprague-Dawley（SD）大鼠,30 d后测定大鼠盲肠内容物各项指标和盲肠、小肠的理化指标。结果：KOS可以明显增加大鼠粪便含水率及盲肠壁表面积、小肠的拉伸性能、盲肠内容物中双歧杆菌和乳酸菌的数量;降低盲肠内容物pH值及含水率、游离氨及挥发性醛类和含氮类物质含量;抑制大肠杆菌和梭状芽孢杆菌的生长,增加短链脂肪酸的产生量。结论：KOS可以调节大鼠肠道菌群组成,改善肠道环境,促进肠道健康,是一种优良的益生元。     

纳米甘薯渣纤维素对高脂膳食大鼠肠道内环境及形态的影响

目的：探讨纳米甘薯渣纤维素对高脂膳食大鼠肠道内环境及形态的影响。方法：选用40 只Sprague-Dawley（SD）成年雄性大鼠随机分为5 组,其中1 组大鼠喂食基础饲料（正常组）,另外4 组大鼠喂食高脂饲料和添加不同粒度甘薯渣纤维素的高脂饲料,分为对照组、普通甘薯渣纤维素组（OC组）、微晶甘薯渣纤维素组（MCC组）和纳米甘薯渣纤维素组（CNC组）,实验期28 d后解剖,测定大鼠采食量、体质量、盲肠组织和盲肠内容物相关指标、粪便干质量、小肠液干质量和总胆汁酸含量、小肠形态等。结果：纳米甘薯渣纤维素可以显著降低高脂膳食大鼠体质量和盲肠游离氨含量,显著升高盲肠组织各项指标、盲肠内容物短链脂肪酸含量、pH值以及小肠液总胆汁酸含量（P＜0.05）,同时具有增加小肠绒毛长度及肌层厚度的作用。结论：随着甘薯渣纤维素粒度的减小,其对肠道内环境及形态作用愈加明显,说明纳米甘薯渣纤维素能有效降低SD雄性大鼠体质量,提高其肠道健康。     

5 种食品原料对高脂饮食诱导的肥胖大鼠肠道菌群和短链脂肪酸的影响

香蕉粉、魔芋精粉、抗性糊精、玉米淀粉以及左旋肉碱这5 种食品原料据报道都有减肥功能,但它们对肠道微生物和代谢产物的影响以及与肠道菌群相关的减肥机制的差异尚不清楚。本研究采用16S rRNA测序检测肥胖大鼠肠道内容物,并通过高效液相色谱法（high performance liquid chromatography,HPLC）测定粪便中短链脂肪酸的含量。结果显示：益生菌属Ruminococcus_2、Coprococcus_2和Ruminiclostridium_5分别在玉米淀粉、香蕉粉和抗性糊精组中富集。Spearman相关性分析和典型关联分析（canonical correlation analysis,CCA）结果表明,肠道微生物的变化与糖脂代谢相关的生化参数密切相关。以可溶性膳食纤维为主的原料（魔芋粉和抗性糊精）和以不可溶性膳食纤维（抗性淀粉）为主的原料（香蕉粉和玉米淀粉）对短链脂肪酸的产生能力贡献度相当,均优于左旋肉碱。5 种原料增殖肠道益生菌、抑制有害菌的效果依次为抗性糊精＞香蕉粉＞玉米淀粉＞魔芋精粉,增加短链脂肪酸含量的能力依次为香蕉粉＞抗性糊精＞玉米淀粉＞魔芋精粉,而左旋肉碱对肠道菌群和短链脂肪酸几乎没有什么影响。CCA结果显示,糖脂代谢生化指标与肠道微生物群落的相关程度为空腹血糖水平＞高密度脂蛋白胆固醇水平＞总胆固醇水平＞低密度脂蛋白胆固醇水平＞总甘油三酯水平。Spearman相关性分析表明Ruminococcus_2与丁酸含量呈正相关,Escherichia.Shigella与乙酸、丁酸和总短链脂肪酸含量呈正相关。     

不同加工方式对青稞降脂益肠功效的影响

目的：探讨不同加工方式对青稞生理功效的影响。方法：按体质量将去势大鼠随机分为5 组,分别为空白组、炒制处理组、微波处理组、蒸煮处理组、挤压膨化处理组。分别饲喂对应的实验饲料4 周后,测定大鼠血脂、盲肠内容物中菌群、代谢产物等指标。结果：不同加工方式处理的青稞均能增加盲肠组织、盲肠内容物、盲肠内容物中短链脂肪酸（short-chain fatty acids,SCFAs）和高密度脂蛋白（high-density lipoprotein cholesterol,HDL-C）含量,降低肠道pH值、肠内容物游离氨、血清总胆固醇、甘油三酯和低密度脂蛋白（low density lipoproteincholesterol,LDL-C）含量,以及促进有益菌并抑制有害菌的增殖。结论：不同加工方式处理的青稞均有一定程度的改善肠道健康和降血脂作用,其中微波处理组和挤压膨化处理组效果较好。     

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