列当不同提取物降糖作用研究

目的研究列当不同提取物的降糖作用。方法本试验提取列当多糖、醇提物及水提物,应用四氧嘧啶建立小鼠糖尿病模型,并对列当提取物的降血糖作用进行综合评价。结果多糖和醇提物的低剂量、水提物中剂量均可显著降低小鼠的血糖值(P0.05)。其中醇提物低剂量组效果明显,对糖尿病具有一定的预防及治疗作用。多糖低剂量、醇提物和水提物的高剂量对体重的作用比较明显,其中水多糖低剂量组对糖尿病小鼠的体重有明显的提高。多糖3个剂量和醇提物中剂量、水提物高剂量组显著降低小鼠血脂(P0.05)。结论列当不同提取物多糖、水提物、醇提物具有明显的降血糖作用。     

茯苓不同溶剂提取物改善小鼠睡眠作用的比较

比较茯苓不同溶剂提取物改善小鼠的睡眠作用。通过直接睡眠实验、延长戊巴比妥钠睡眠时间实验、戊巴比妥钠阈下剂量催眠实验和巴比妥钠睡眠潜伏期实验研究茯苓不同溶剂提取物改善小鼠的睡眠作用,通过测定小鼠脑组织中5-HT、GABA和DA含量变化探讨茯苓不同溶剂提取物改善小鼠睡眠作用机制。结果显示,与空白对照组相比,水提物高剂量组(112.7 mg/kg)效果最佳(p0.05),其后是醇提物高剂量组(100.8 mg/kg)、多糖高剂量组(15.6 mg/kg)、水提物低剂量组(56.4 mg/kg)、醇提物低剂量组(50.4mg/kg),而多糖低剂量组(7.8 mg/kg)效果不明显(p0.05),其中,水提物高剂量组小鼠睡眠时间由1829.67 s显著延长至2979.83 s,睡眠发生率由10%显著提高至60%,睡眠潜伏期由2033.50 s显著缩短至1486.25 s;且茯苓不同溶剂提取物改善小鼠睡眠的效果与其调节小鼠脑组织中GABA和5-HT含量升高及DA含量下降的趋势相一致,其中,水提物高剂量组5-HT含量升至26.96 pg/mg,GABA含量升至817.40 pg/mg,DA含量降至3.41 pg/mg。本研究结果显示水提物高剂量组改善睡眠效果最佳,其作用机制与调节小鼠脑中GABA、5-HT和DA含量有关。     

苦瓜提取物抗氧化及抑制淀粉酶协同作用研究

通过析因设计研究不同溶剂苦瓜提取物的协同作用,为苦瓜功能保健食品的开发提供参考。以邻二氮菲-Fe2+氧化法抗氧化试验及α-淀粉酶的抑制试验研究苦瓜醇提物和水提物的剂量-反应关系,并进行3×3析因设计,通过析因分析研究苦瓜醇提物与水提物的协同作用。结果表明苦瓜的醇提物和水提物在抗氧化及α-淀粉酶抑制作用方面存在协同作用。协同抗氧化效果最好组合是水提物0.2 mg/m L,醇提物0.15 mg/m L;协同抑制α-淀粉酶效果最好的组合是水提物40 mg/m L,醇提物30 mg/m L。     

百合水提物对对氯苯丙氨酸失眠模型大鼠睡眠改善作用研究

目的 研究不同剂量的百合水提取物对对氯苯丙氨酸(PCPA)失眠模型大鼠睡眠作用的影响。方法 大鼠腹腔注射PCPA混悬液制备大鼠失眠模型。将造模成功大鼠随机分为模型对照组、百合水提物组-低、百合水提物组-中、百合水提物组-高,另设空白对照组。百合水提物组-低 (100 mg/kg.d)、百合水提物组-中(200 mg/kg.d)、百合水提物组-高(300 mg/kg.d)大鼠连续 7 d 给予相应浓度药液,模型对照组和空白对照组连续 7 d 给予生理盐水灌胃。给药期间,观察大鼠一般状态;给药结束后,观察大鼠体质量变化、睡眠潜伏期、总睡眠时间,同时评价不同脑组织中五羟色胺、5-羟基吲哚乙酸、多巴胺含量的变化。结果 百合水提物各剂量组的大鼠在给药期间的一般状态均优于模型组,体质量增加情况也与正常对照组无显著差异;百合水提物中、高剂量组的睡眠潜伏期与模型组相比显著缩短(P＜0.05),百合水提物各剂量组的睡眠时间与模型组相比显著延长(P＜0.05);与模型对照组比较,各给药组大鼠不同脑组织中的5-HT含量显著升高(P < 0.05,P < 0.01),百合水提物中、高剂量组大鼠不同脑组织中的5-HIAA 含量显著升高(P < 0.05,P < 0.01),同时上述２个给药组大鼠的下丘脑、中缝核中的DA含量显著降低(P < 0.05),海马中仅百合水提物高剂量组的DA含量与对照组相比显著降低(P < 0.05)。结论 百合水提物具有改善PCPA失眠模型大鼠睡眠情况的作用。     

水生蔬菜提取物的抗氧化活性分析及其对菜籽油的抗氧化作用

研究七种常见水生蔬菜不同部位提取物的抗氧化活性以及对油脂抗氧化的效果。采用ABTS自由基清除法、DPPH自由基清除法检测菱角、芡实、莲藕、水芋头、茭白、荸荠和慈姑不同部位的醇提物、水提物的抗氧化活性,烘箱法测定对菜籽油过氧化值的影响。在30种提取物中DPPH自由基清除能力较强的三种提取物IC50值分别为:芡实壳醇提物(0.03 mg/mL)芡实壳水提物(0.04mg/m L)=菱角壳醇提物(0.04mg/m L);ABTS自由基清除能力较强的三种提取物Trolox含量分别为芡实壳醇提物(1.42g/g)芡实壳水提物(1.41 g/g)菱角壳醇提物(1.15 g/g);添加0.1%浓度的五种提取物第7 d的POV值分别为23.86 meq/kg、24.06 meq/kg、23.53meq/kg、24.43 meq/kg、22.40 meq/kg,五种提取物的油脂抗氧化效果均不如0.1%浓度的BHA。30种水生蔬菜提取物中,芡实壳和菱角壳的醇提物、水提物DPPH自由基清除能力最强,芡实壳醇提物、水提物ABTS自由基清除能力最强;芡实壳水提物、芡实壳醇提物、菱角壳水提物、菱角壳醇提物以及藕节醇提物对菜籽油有一定抗氧化的效果,但效果弱于相同剂量的BHA。     

菊苣仔根提取物对高脂血症仓鼠血脂的影响

探讨菊苣仔根提取物的降血脂功效.将雄性仓鼠随机分为6组,分别为空白组、模型组、添加菊苣仔根水提物及醇提物低、高剂量组(高脂饲料中质量分数均分别为1.0％、5.0％),饲养6周后对仓鼠进行眼底静脉丛采血,并检测相关指标.结果显示,与高脂模型组相比,添加菊苣仔根水提物及醇提物的低、高剂量组仓鼠血清中的总胆固醇(TC)、甘油三酯(TG)及非高密度脂蛋白胆固醇(non-HDL-C)水平均极显著降低(p＜0.01),水提物和醇提物高剂量组高密度脂蛋白胆固醇(HDL-C)水平呈极显著和显著升高(p＜0.01)、(p＜0.05),水提物低、高剂量组和醇提物高剂量组仓鼠血清和肝脏中的MDA含量均呈不同程度的降低.结论:菊苣仔根水提物和醇提物对高脂血症仓鼠血脂水平均具有降低作用,并有抑制脂质过氧化的作用.醇提物在降低总胆固醇(TC)、甘油三酯(TG)水平方面略优于水提物,而水提物对于高密度脂蛋白胆固醇(HDL-C)水平的升高作用则更加明显.     

山稔子提取物降血脂作用的研究

目的:研究山稔子提取物的降血脂作用。方法:分别用70%乙醇和蒸馏水对山稔子干粉进行回流提取,浓缩得到山稔子醇提物和水提物。在测定提取物中总多糖、总皂苷、总黄酮、总多酚含量的基础上,通过模拟人体胃肠道环境进行离体实验,对比分析山稔子干粉和2种提取物对胆酸盐的结合能力;以高脂饲料喂养小鼠建立高血脂模型,分别用不同剂量的2种提取物进行灌胃饲养,29 d后检测小鼠体重及血脂4项指标,并计算血脂综合指数(LCI)和动脉粥样硬化指数(AI)。结果:山稔子醇提物结合胆酸盐的能力较强。小鼠实验结果表明,与模型对照组相比,醇提物高剂量组的小鼠体重显著降低(P0.05),醇提物中、高剂量组和水提物高剂量组的小鼠血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)水平和LCI、AI值均显著降低(P0.05)。结论:山稔子醇提物和水提物都具有一定的降血脂作用。     

基于高通量测序分析毛菊苣醇提物对db/db小鼠肠道菌群的影响

该文探究毛菊苣醇提物对糖尿病小鼠（db/db小鼠）肠道菌群的影响。该研究以m/m小鼠为正常对照组（CON组）,db/db小鼠随机分为模型组（MOD组）、二甲双胍组（MET组）、毛菊苣醇提物低剂量组（CGL组）、毛菊苣醇提物高剂量组（CGH组）。灌胃给药8周,对小鼠体质量、空腹血糖、肝脏总胆固醇（TC）、甘油三酯（TG）进行分析,对小鼠粪便进行16S rRNA测序分析,探究毛菊苣醇提物对小鼠肠道菌群的影响。毛菊苣醇提物高剂量组可调节db/db小鼠体质量及血糖,显著降低db/db小鼠TC、TG水平（P<0.05）;测序结果显示CON组、MOD组、CGH组三组小鼠肠道菌群情况存在差异,毛菊苣醇提物给药可改善db/db 小鼠的肠道菌群失调,上调db/db小鼠肠道菌群中有益菌双歧杆菌属（Bifidobacterium）、Romboutsia、普雷沃氏菌属（Prevotella）菌群相对丰度。研究证明了毛菊苣醇提物给药能调节db/db小鼠肠道菌群,通过提高有益菌相对丰度调节糖脂代谢,可为新疆地产毛菊苣药材资源的开发利用提供全新的研究思路。     

食用玫瑰花水提物对大鼠肠道微生物和基因表达的影响

利用16S rDNA测序方法研究大鼠灌胃玫瑰水提物对肠道微生物的影响,结合转录组测序结果探讨玫瑰水提物对机体的功能作用。选用6周龄SD大鼠,灌胃蒸馏水作为对照组,实验组分别灌胃低、中、高剂量玫瑰水提物,每组8只。结果表明:低、中、高剂量玫瑰水提物均对正常大鼠血脂和生长发育指标无显著影响;不同组别的大鼠粪便中普雷沃氏菌科(Prevotellaceae)和盲肠内容物中普雷沃氏菌属(Prevotella)含量差异明显,均为高剂量组<对照组<中剂量组<低剂量组;与对照组相比,不同剂量的玫瑰水提物均显著影响大鼠肝脏的转录组学,低剂量玫瑰水提物有101个差异表达基因,显著富集于抗原加工和提呈(ko04612)通路;中剂量组也有101个差异表达基因,主要集中在抗原加工和提呈、TNF信号通路(ko04668)等4条通路高剂量组有76个差异表达基因,主要集中在抗原加工和提呈、MAPK信号通路(ko04010)等6条通路不同剂量之间也有明显变化。这说明玫瑰水提物对大鼠肠道普雷沃氏菌属影响较大,同时也显著影响肝脏免疫应答。提示玫瑰水提物可通过干预肠道微生物多样性进而影响机体健康,并具有潜在的诱导肿瘤细胞衰老和提高机体免疫功能的作用。     

桂花醇提物对雌性果蝇抗氧化活性及延缓衰老的研究

目的:研究桂花醇提物延长寿命及应激状态下抗衰老的活性。方法:乙醇提取桂花减压浓缩后得桂花醇提物,进行雌性果蝇的生存试验和应激试验,测定平均寿命、最高寿命绘制生存曲线及体内蛋白质、丙二醛含量和过氧化氢酶、超氧化物歧化酶活性。结果:桂花醇提物能够延长雌性果蝇的寿命,有一定的抗衰老活性,在一定范围随剂量而增加,10、15mg/m L剂量组与对照组有显著的差异性(P0.01),应激状态下桂花醇提物15mg/m L剂量组与对照组有显著的差异性(P0.01)。结论:桂花醇提物具有延长寿命的作用,在应激条件下也有一定的抗衰老活性,尤其是15mg/m L剂量时效果显著,可重点针对高浓度剂量研究其抗衰老活性并明确分子机制。     

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.     

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.     

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.     

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.     

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.