白藜芦醇的雌激素作用研究

目的探索反式白藜芦醇经口摄入后,在体内的雌激素作用和剂量一反应关系。方法选用19日龄未成年大鼠做子宫增重试验,分别经灌胃给予0．1、0．3、0．6和1．0g／kgBW的白藜芦醇,以3．0p∥kgBW的雌二醇为阳性对照,并设立水和油的阴性对照组,所有剂量组连续灌胃3d。实验结束称量子宫的湿重和干重,对卵巢、子宫和阴道进行组织病理学检查,并测量子宫内膜上皮细胞高度。结果和对照组比较,白藜芦醇对子宫重量无影响;组织病理学结果显示,1．0g／kgBW白藜芦醇剂量组的子宫轻度增生,0．3、0．6和1．0g／kgBW白藜芦醇剂量组的阴道轻度增生,无剂量-反应关系;受试物组子宫内膜上皮细胞高度无明显变化。结论白藜芦醇经口摄入时雌激素作用较弱,且无剂量-反应关系。     

金雀异黄素对PCOS大鼠卵巢和子宫组织中P450arom mRNA的作用

目的:通过建立多囊卵巢综合征(PCOS)高雄血症动物模型,观察金雀异黄素(GEN)对大鼠卵巢组织中雌雄激素转换关键酶P450芳香化酶(P450arom)的影响。方法:按照胰岛素(INS)联合HCG造模法建立实验动物模型,分为阴性对照组、模型组、GEN低、中、高剂量组及雌激素阳性对照组,其中剂量组分别灌胃GEN 5,10,20 mg/(kg体质量),雌激素组给予己烯雌酚0.5 mg/kg,持续15 d,观察动情周期10 d。实验结束后,取大鼠血液、子宫和卵巢,ELISA方法测定大鼠血清中雌二醇(E2)、睾酮(T)水平,并计算E2/T比值。RT-PCR法测定大鼠子宫和卵巢中P450arom m RNA表达情况。结果:与模型组相比,中、高剂量组及雌激素组大鼠血清E2水平上升,差异显著(P0.05);各GEN剂量组大鼠血清睾酮水平下降,差异不显著(P0.05);各GEN剂量组及雌激素组E2/T比值升高,差异显著(P0.05)。与模型组相比,高剂量组大鼠卵巢和子宫中P450arom m RNA水平下降明显(P0.05),差异显著;中、低剂量组大鼠卵巢和子宫中P450arom m RNA水平也呈下降趋势,差异不显著(P0.05)。结论 :不同剂量GEN可通过升高大鼠血清E2/T比值,拟补芳香化酶芳香化的缺陷;高剂量【20 mg/(kg体质量)】金雀异黄素可使PCOS大鼠卵巢和子宫组织中P450arom m RNA表达量显著升高,其效果与雌激素相近。     

玫瑰精油抗血栓形成作用

目的：研究玫瑰精油对大鼠体外全血血小板聚集以及大鼠动-静脉旁路血栓形成的影响。方法：大鼠颈总动脉取血后,随机分为溶剂对照组,阿司匹林阳性对照组,玫瑰精油高(100μg/mL)、中(50μg/mL)、低(25μg/mL)剂量组,分别采用血小板聚集诱导剂二磷酸腺苷(ADP)、钙离子载体(A23187)和CaCl2激发血小板聚集,以电阻法分别检测玫瑰精油对体外全血血小板聚集的抑制作用。取Wistar大鼠50只,均于手术前3d进行分组灌胃给药,即溶剂对照组,阿司匹林阳性对照组(30mg/(kg ·d)),玫瑰精油(溶于注射用大豆油)高(100mg/(kg ·d))、中(50mg/(kg ·d))、低(25mg/(kg ·d))剂量组,然后采用大鼠动-静脉旁路血栓形成法观察玫瑰精油对血栓形成的抑制作用。结果：玫瑰精油能显著抑制ADP、A23187、CaCl2诱导的大鼠血小板聚集和动-静脉旁路血栓的形成。     

大豆异黄酮对新生儿期大鼠子宫发育和雌激素受体表达的影响

目的研究母鼠暴露于大豆异黄酮对新生儿期大鼠子宫发育及雌激素受体表达的影响。方法将母鼠及其仔鼠随机分至6组,母鼠的大豆异黄酮暴露剂量分别为0、10、50、100、150、200mg/kgBW（i.g.）,暴露时间为产后第5至10天（PND5~10）。在PND11处死雌性仔鼠,称量子宫重量并进行病理学检查,利用ELISA方法测定血清雌二醇（E2）和孕酮（P）浓度,利用RT-PCR方法测定子宫中雌激素受体（ER）mRNA的表达。结果与对照组比较,大豆异黄酮150、200mg/kgBW剂量组仔鼠的子宫/体重比显著增加,子宫内膜增厚的差异有统计学意义（P〈0.05）;血清E2浓度明显高于对照组,SIF150组升高幅度最大,但各处理组血清P浓度呈下降趋势;100、150、200mg/kgBW剂量组仔鼠的子宫ERmRNA表达降低的差异有统计学意义（P〈0.05）。结论大豆异黄酮经母鼠暴露,可刺激雌性仔鼠的子宫发育,这种雌激素样效应至少与该物质对血液性激素和子宫ERmRNA表达的调节作用有关。     

雌激素与山核桃油干预对去卵巢大鼠海马早老基因-1与载脂蛋白E基因表达的影响

目的：观察雌激素干预后,核桃油对去卵巢大鼠海马组织早老基因-1(PS-1)与载脂蛋白E(aproE)基因表达及匀浆液中β淀粉样肽(Aβ)含量的变化。探讨核桃油对PS-1、aproE 表达的调节与雌激素(E2)间的关系。方法：以去卵巢雌性大鼠为动物模型,实验组灌胃给予核桃油100mg/(kg bw·d)(低剂量组)、200mg/(kg bw·d)(中剂量组)、400mg/(kg bw·d) (高剂量组) (n=16)。空白组给予相同剂量的生理盐水。各组一半的大鼠随机接受E2 处理,采用RT-PCR 检测大鼠海马PS-1 与aproE 基因表达,RIA 检测海马Aβ的含量的变化,放免法测血清E2 水平。结果：雌激素干预的模型鼠血清E2 水平显著高予未干预组(P ＜ 0.01);海马Aβ含量空白组最高,随核桃油剂量增加Aβ含量逐渐下降,中、高剂量组更显著(P ＜ 0.05),E2 干预后Aβ含量下降更明显;空白组PS-1 的表达最高而apoE 的表达最低,随核桃油剂量增加各剂量组PS-1 的表达仅轻度下降,apoE-mRNA 表达明显增加;雌激素干预后PS-1 的表达有所下降,apoE 基因各组间表达差异消失。结论：E2 和核桃油都可以通过降低去卵巢大鼠海马的PS-1 基因及增加aproE 基因的表达来降低Aβ的水平;但二者对PS-1 基因调节可能通过不同的途径实现,而对apoE基因可能通过相同的途径来调节。     

95%水胺硫磷慢性毒性和致癌性研究

目的研究95%水胺硫磷的慢性毒性和致癌性,提出其未观察到有害作用水平。方法480只断乳SD大鼠按体重随机分成4组,每组120只,雌雄各半。4组大鼠喂饲含有不同浓度水胺硫磷的块料,对照组、低剂量组、中剂量组和高剂量组的剂量分别是0、0.6、6和30mg/kg饲料,试验期2年。观察大鼠日常表现,检测体重、进食量、血常规、凝血时间、血生化、胆碱酯酶、尿常规等指标并进行大体和病理组织学检查,计算食物利用率、脏器系数和肿瘤发生率。结果试验第6、18、24个月,高剂量组雌性大鼠胆碱酯酶活性显著低于对照组(P0.01);试验第6、12、18和24个月,中、高剂量组雄性大鼠胆碱酯酶活性显著低于对照组(P0.01)。各组大鼠的其他指标,包括肿瘤发生率差异均无统计学意义。结论根据胆碱酯酶的检测结果确定水胺硫磷的未观察到有害作用水平:雌性为0.468mg/(kgBW·d)(中剂量),雄性为0.037mg/(kgBW·d)(低剂量)。未见致癌作用。     

大豆异黄酮对青年雌性大鼠卵巢、子宫组织中Bcl-2 mRNA 和Bax mRNA 表达的影响

目的：通过动物实验研究,观察Bcl-2 mRNA 和Bax mRNA 在青年雌性大鼠卵巢和子宫组织中的表达情况,从细胞凋亡角度研究大豆异黄酮对青年雌性大鼠的抗衰老作用。方法：选用2 月龄青年雌性大鼠50 只,按体质量分成5 组,每组10 只,分别为对照组(基础饲料)、低剂量组(大豆异黄酮100mg/(kg bw·d))、中剂量组(大豆异黄酮200mg/(kg bw·d))、高剂量组(大豆异黄酮300mg/(kg bw·d))、雌激素组(己烯雌酚0.5mg/kg 饲料),实验周期7 周。采用原位杂交法检测各组大鼠卵巢和子宫组织中Bcl-2 mRNA 和Bax mRNA 的表达水平。结果：大豆异黄酮能够增强大鼠卵巢和子宫组织中Bcl-2 mRNA 的表达水平;而各剂量组大鼠卵巢和子宫组织中Bax mRNA水平呈下降趋势。结论：大豆异黄酮可以增强抗凋亡基因Bcl-2 mRNA,拮抗促凋亡基因Bax mRNA 的水平,推测这是大豆异黄酮对青年雌性大鼠发挥抗衰老作用的途径之一。     

转Cry1Ac/SCK基因糙米作鲤鱼日粮原料营养学评价

利用转Cry1Ac/SCK基因糙米制作饲料,以亲本糙米为对照组,进行56 d饲喂鲤鱼试验;于饲喂28 d和56 d后,评价转Cry1Ac/SCK基因糙米对鲤鱼生长性能和肌肉组成成分的影响.结果表明:转Cry1Ac/SCK基因糙米与亲本糙米相比,水分、粗蛋白质、粗脂肪、粗灰分、粗纤维、氨基酸、钙和总磷等指标均无显著差异(P＞0.05);在第一生长阶段(1～28 d)和第二生长阶段(29～56 d),转Cry1Ac/SCK基因糙米组与亲本糙米组相比,鲤鱼的生长性能和肌肉营养成分指标未见显著差异(P＞0.05).     

排铅食品对铅中毒小鼠的排铅作用

目的评价排铅食品对铅中毒小鼠的排铅功效。方法选用90只18～22g昆明种雄性小鼠,随机分为6组:阴性对照组,醋酸铅模型组,阳性药物组,排铅受试物低剂量组、中剂量组和高剂量组。除阴性对照组自由饮用去离子水外,其他各组均自由饮用1.00g/L醋酸铅水溶液染毒。30d后,剂量组按人体推荐摄入量0.60g/(kgBW·d)的5、10和20倍经口灌胃排铅受试物,阳性药物组灌胃二巯基丁二酸(dimercaptosuccinic acid)溶液,模型对照组和阴性对照组灌胃去离子水。1个月后测定全血、肝、股骨、肾和脑中铅含量。结果排铅食品3个剂量组血、肝、肾和脑铅含量比醋酸铅模型组明显降低(P0.05或P0.01),高、中剂量组股骨铅含量比醋酸铅模型组明显降低(P0.01)。结论排铅食品具有明显促进小鼠体内铅排出作用。     

酸枣仁提取物与茶氨酸复合配方对睡眠的改善作用

为探究酸枣仁提取物与茶氨酸的复合配方对小鼠睡眠的影响及其作用机理,将雄性Balb-c小鼠随机分成3组,酸枣仁提取物、茶叶茶氨酸低剂量组[酸枣仁提取物105 mg/(kg·d)、茶氨酸58 mg/(kg·d)]和高剂量组[酸枣仁提取物158 mg/(kg·d)、茶氨酸87 mg/(kg·d)],以及对照组(蒸馏水),连续...     

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