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胡萝卜汁加工与贮藏过程中胡萝卜素含量稳定性的研究

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食品科学 1992年第9期 52-54页

作者：廖显珍湖北省农科院加工所

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番茄红素对乳腺癌MDA-MB-231细胞周期和增殖的影响

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陕西医学杂志 2008年第11期37卷 1482-1484页

作者：王爱红王明全庞秋霞张立实延安大学医学院延安716000 延安大学附属医院介入放射科四川大学华西公共卫生学院

目的:研究番茄红素对体外培养的雌激素受体阴性(ER-)细胞MDA-MB-231的抑制作用及其可能作用机制。方法:采用MTT法和H3-TdR掺入法观察番茄红素对乳腺癌细胞增殖的影响;流式细胞仪观察同步化的细胞经番茄红素作用后细胞周期及凋亡的变化,R... 详细信息

目的:研究番茄红素对体外培养的雌激素受体阴性(ER-)细胞MDA-MB-231的抑制作用及其可能作用机制。方法:采用MTT法和H3-TdR掺入法观察番茄红素对乳腺癌细胞增殖的影响;流式细胞仪观察同步化的细胞经番茄红素作用后细胞周期及凋亡的变化,RT-PCR检测cyclinD1、bcl-2、bax的mRNA表达的变化。结果:番茄红素抑制MDA-MB-231细胞的增殖和DNA合成、诱导其凋亡、改变细胞周期分布(使G0/G1期细胞增多、而S期和G2/M期细胞减少)。RT-PCR结果显示cyclinD1和bcl-2的mRNA表达水平下调,而bax的mRNA表达水平上调。上述作用呈剂量效应关系。结论:番茄红素可诱导MDA-MB-231细胞凋亡、改变细胞周期分布、影响cyclinD1、bcl-2、bax的mRNA的表达,从而达到抑制肿瘤细胞增殖的可能。

关键词：类胡萝卜素类/分析乳腺肿瘤/病理学 @MDA-MB-231细胞细胞分裂细胞周期细胞凋亡

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Effect of selenium and vitamin E content of the maternal diet on the antioxidant system of the yolk and the developing chick

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BRITISH POULTRY SCIENCE 2000年第2期41卷 235-243页

作者： Surai, PF Scottish Agr Coll Dept Biochem & Nutr Auchincruive KA6 5HW Ayr Scotland

1. The effects of selenium and vitamin E supplementation of the maternal diet on their transfer to the egg yolk and tissues of the newly hatched chick and on the development of the antioxidant system in the chick liver in early postnatal life were investigated. 2. One hundred Cobb broiler breeder hens were divided into 10 equal groups and housed in pens at 25 weeks of age. Each hen received 1 of the treatment diet which included 0.2 or 0.4 mg/kg selenium, 40, 100, 200 mg/kg vitamin E or their combination. After 6 weeks, the hens M-ere artificially inseminated once per week. From week 8, eggs were collected and placed in an incubator. After hatching, chicks from each group were reared (under standard commercial conditions) to 10d of age. The chicks were fed on a standard starter commercial broiler diet. At the time of hatching, and at 5 and 10 days old, 4 chicks from each group were sacrificed and blood, liver and brain were collected for the subsequent biochemical analyses. 3. The inclusion of organic selenium or vitamin E in the commercial diet significantly increased their concentration in the egg and in the Liver of 1-d-old chicks obtained from the eggs enriched with these substances. A positive effect of such dietary supplementation was seen at d 5 and d 10 of postnatal development. *** was a positive effect of selenium supplementation of the maternal diet on glutathione concentration in the liver of 1-d-old and 5-d-old chicks. A combination of a dietary selenium supplementation with high vitamin E doses further increased glutathione concentration in the liver Dietary selenium supplementation significantly increased selenium-dependent glutathione peroxidase (Se-GSH-Px) activity in the liver of the 1-d-old and 5-d-old chicks and decreased liver susceptibility to peroxidation. 6. It is concluded that the nutritional status of the laying hen determines the efficiency of the antioxidant system throughout embryonic and early postnatal development of the offspring

关键词：动物饲料脑化学/生理学类胡萝卜素类/分析鸡/生长和发育鸡/生理学色谱法高压液相/兽医学营养保健品蛋黄/化学谷胱甘肽/血液谷胱甘肽过氧化酶/分析肝/化学丙二醛/分析硒/投药和剂量硒/血液硒/生理学分光光度法原子/兽医学维生素E/投药和剂量维生素E/血液维生素E/生理学动物鸡胚女(雌)性男(雄)性

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Value assignment of retinol, retinyl palmitate, tocopherol, and carotenoid concentrations in Standard Reference Material 2383 (Baby Food Composite)

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JOURNAL OF AOAC INTERNATIONAL 1999年第2期82卷 288-296页

作者： Sharpless, KE Arce-Osuna, M Thomas, JB Gill, LM Natl Inst Stand & Technol Gaithersburg MD 20899 USA

In 1997, the National institute of Standards and Technology (NIST) released Standard Reference Material (SRM) 2383 Baby Food Composite, This SRM can be used as a control material when assigning values to in-house control materials and when validating analytical methods for the measurement of proximates, vitamins, minerals, and trace elements in baby foods and similar matrixes. The Certificate of Analysis for SRM 2383 provides certified and reference values for concentrations of lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, beta-carotene, delta-tocopherol, gamma-tocopherol, alpha-tocopherol, retinol, and retinyl palmitate for 2 types of sample preparation-extraction and saponification, The assigned values were based on the agreement of measurements made by NIST and collaborating laboratories. The Certificate of Analysis also provides reference and information values for concentrations of proximates, minerals, and additional vitamins;assignment of these values is discussed in a companion paper (this issue, page 276).

关键词：类胡萝卜素类/分析色谱法/方法色谱法/标准婴儿食品/分析质量控制参考标准参考值维生素A/类似物和衍生物维生素A/分析维生素E/分析

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Development and evaluation of a new method for the determination of the carotenoid content in selected vegetables by HPLC and HPLC-MS-MS

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JOURNAL OF CHROMATOGRAPHIC SCIENCE 2000年第10期38卷 441-449页

作者： Huck, CW Popp, M Scherz, H Bonn, GK Univ Innsbruck Inst Analyt Chem & Radiochem A-6020 Innsbruck Austria Bionorica Plantamed GMBH D-92318 Neumarkt Oberpfalz Germany Deutsch Forsch Anstalt Lebensmittelchem D-85748 Garching Germany

Epidemologic studies have shown inverse correlation between the consumption of carotenoid-rich vegetables and the incidence of cancer. Therefore, analytical techniques for the quantitative determination of carotenoids in complex sample matrices are important. The most used method is reversed-phase (RP)-high-performance liquid chromatography (HPLC). In this study, seventeen mobile-phase systems described in the literature and six RP-HPLC columns with differences in particle size and porosity are evaluated. Derived from these results, a new mobile-phase (acetonitrile, methanol, chloroform, and n-heptane) including solvent modifiers is presented, which allows an improved and more efficient separation of carotenoids. From all columns tested, the best chromatographic parameters are found using a silica C18 column (250 ￥ 2 mm, 5 μm, 100 A). As was found, absorbance detection at 450 nm allows the determination of the carotenoids down to the picogram range with good linearity (R2 > 0.98). For the identification and quantitation of carotenoids in complex sample matrices (containing additionally other ultraviolet-absorbing compounds), the optimized RP chromatographic system is coupled to a mass spectrometer (MS) using an atmospheric pressure ionization interface. The calibration plots show high linearity (R2 > 0.99), and the detection limit is found in the lower nanogram range. Furthermore, collision-induced dissociation in the ion source allows for the identification of carotenoids by their characteristic fragmentation pathways. In this study, a total of nine species of vegetables commonly consumed in Central Europe are analyzed for their contents of carotenoids (namely lutein, zeaxanthin, b-cryptoxanthin, and b-carotene) by RP-HPLC and RP-HPLC–MS–MS. It is found that good sources for lutein are spinach, kale, and broccoli, and sources for b-carotene are broccoli, spinach, kale, carrots, and tomatoes. This new method is an improvement for the identification and quantitation

关键词：类胡萝卜素类/分析色谱法高压液相/方法质谱分析法/方法参考标准蔬菜/化学

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Liquid chromatographic determination of carotenoids and vitamins A and E in multivitamin tablets

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JOURNAL OF AOAC INTERNATIONAL 1999年第1期82卷 68-72页

作者： Sun, JD Enzymat Therapy Inc Green Bay WI 54311 USA

Carotenoids and vitamins A and E in multivitamin tablets can be determined simultaneously by reversed-phased liquid chromatography (LC) with a programmable UV detector. Samples were dissolved in dimethyl sulfoxide and then extracted with hexane. A portion was injected onto a Symmetry C-18, 150 x 4.6 mm id, 5 mu m column and chromatographed with a mobile phase of acetonitrile- 0.25% ammonium acetate in methanol and 0.05% triethylamine in dichloromethane. A step gradient was used. The system was operated at 25 degrees C with a flow rate of 1.5 mL/min. UV detection was at 325 nm for retinols, 285 nm for tocopherols, and 450 nm for carotenoids. Detection limits were less than 0.3 ng for retinol and retinyl acetate;2 ng for alpha-tocopherol acid succinate;10 ng for alpha-tocopherol, gamma-tocopherol, and alpha-tocopherol acetate;and 0.4 ng for alpha-carotene and beta-carotene. Intraday and interday coefficients of variation ranged from 1.40 to 5.20%. The sample preparation method and LC assay are practical for quality control and routine analysis of multivitamin tablets.

关键词：类胡萝卜素类/分析色谱法液相复方合剂结果可重复性片剂维生素A/分析维生素E/分析

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Preparation of Standard Reference Material 2383 (Baby Food Composite) and use of an interlaboratory comparison exercise for value assignment of its nutrient concentrations

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JOURNAL OF AOAC INTERNATIONAL 1999年第2期82卷 276-287页

作者： Sharpless, KE Gill, LM Margolis, SA Wise, SA Elkins, E Natl Inst Stand & Technol Gaithersburg MD 20899 USA Natl Food Processors Assoc Washington DC 20005 USA

The preparation of the recently released Standard Reference Material (SRM) 2383 Baby Food Composite and the process used for value assignment of nutrient concentrations are reported. SRM 2383 can be used as a control material when assigning values to in-house control materials and when validating analytical methods for measuring proximates, vitamins, and minerals in baby food and similar matrixes. The SRM was prepared as a commercial baby food would be prepared, with the same ingredients. The Certificate of Analysis for SRM 2383 provides assigned values for concentrations of proximates, vitamins, and minerals for which product labeling is required by the Nutrition Labeling and Education Act of 1990. These assigned values were based on measurements by the National institute of Standards: and Technology (NIST) and/or collaborating laboratories. Assignment of analyte concentrations based solely on analyses by collaborating laboratories is described in this paper. Certified values are provided for retinol, tocopherols, and several carotenoids including total beta-carotene the certification of and methodology used for measurement of these analytes is discussed in a companion paper (this issue, page 288). Reference values are provided for solids, ash, fat, nitrogen, protein, carbohydrate, calories, vitamin B-1, vitamin B-2, vitamin B-6, niacin, biotin, calcium, phosphorus, magnesium, manganese, iron, zinc, copper sodium, potassium, and chloride. Reference values for addi tional carotenoids are reported in the companion paper (this issue, page 288). Information values are provided for iodine, selenium, molybdenum, vitamin D, vitamin B-12, folic acid, pantothenic acid, choline, inositol, sugars, total dietary fiber and 3 classes of fats.

关键词：碳水化合物/分析类胡萝卜素类/分析能量摄取脂肪类/分析婴儿食品/分析实验室/标准矿物质/分析氮/分析蛋白质类/分析参考标准参考值维生素A/分析维生素E/分析维生素类/分析

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PCB-induced oxidative stress in the unicellular marine dinoflagellate Lingulodinium polyedrum

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ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2003年第1期45卷 59-65页

作者： Leitao, MAD Cardozo, KHM Pinto, E Colepicolo, P Univ Sao Paulo Inst Quim Dept Bioquim BR-05599970 Sao Paulo Brazil

The susceptibility of the dinoflagellate Lingulodinium polyedrum to Arochlor 1254, a commercial mixture of polychlorinated biphenyl (PCB) congeners was examined through toxicity bioassays based on cell survival and measures of oxidative balance and adaptive response to PCB stress. The highest Arochlor 1254 concentration that did not cause observed effects (NOEL) on cell growth was 100 (48 h) and 25 ppb (96 h). The concentration that caused maximum effect (MEC) was 300 ppb (48 h) and 250 ppb (mul L-1) (96 h). The concentrations that promoted 50% cell death (LC50) were 146 and 122 ppb after 48 and 96 h, respectively. The cell numbers were lower after 96 h of exposure than after 48 h, suggesting that neither recovery nor growth occurred. Under exposure to 120 ppb Arochlor 1254 for 48 h the oxidative damage in proteins was 121% higher than the control, as measured by reactive carbonyl levels, but no oxidative damage was found in lipids measured as malondialdehyde contents. Total superoxide dismutase (SOD) activity increased to plateau levels 146% greater than control values. The cells also exhibited increased ascorbate peroxidase (APx) activity (50%) and peridinin content (27%). No changes were observed in beta-carotene under these experimental conditions. Therefore, SOD and APx induction and increased peridinin content may be principal primary adaptive responses to an increase of reactive oxygen species in Arochlor 1254 stress as indicated by protein oxidative damage and are an early marker of Arochlor 1254 contamination.

关键词：生物学鉴定法类胡萝卜素类/分析腰鞭毛虫目/生理学氧化性应激过氧化物酶类/药理学超氧化物歧化酶/药理学存活率分析动物

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Targeted disruption of the plastid RNA polymerase genes rpoA, B and C1:: molecular biology, biochemistry and ultrastructure

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PLANT JOURNAL 1999年第5期18卷 477-489页

作者： De Santis-Maciossek, G Kofer, W Bock, A Schoch, S Maier, RM Wanner, G Rüdiger, W Koop, HU Herrmann, RG Univ Munich Inst Bot D-80638 Munich Germany

The plastid encoded RNA polymerase subunit genes rpoA, B and C1 of tobacco were disrupted individually by PEG-mediated plastid transformation. The resulting off-white mutant phenotype is identical for inactivation of the different genes. The mutants pass through a normal ontogenetic cycle including flower formation and production of fertile seeds. Their plastids reveal a poorly developed internal membrane system consisting of large vesicles and, occasionally, flattened membranes, reminiscent of stacked thylakoids. The rpo(-) material is capable of synthesising pigments and lipids, similar in composition but at lower amounts than the wild-type. Western analysis demonstrates that plastids contain nuclear-coded stroma and thylakoid polypeptides including terminally processed lumenal components of the Sec but not of the Delta pH thylakoid translocation machineries. Components using the latter route accumulate as intermediates. In striking contrast, polypeptides involved in photosynthesis encoded by plastid genes could not be detected by Western analysis, although transcription of plastid genes, including the rm operon, by the plastid RNA polymerase of nuclear origin is found as expected. Remarkably, ultrastructural, sedimentation and Northern analyses as well as pulse experiments suggest that rpo(-) plastids contain functional ribosomes. The detection of the plastid-encoded ribosomal protein Rpl2 is consistent with these results. The findings demonstrate that the consequences of rpo gene disruption, and implicitly the integration of the two plastid polymerase types into the entire cellular context, are considerably more complex than presently assumed.

关键词：类胡萝卜素类/分析叶绿素/分析指导DNA的RNA聚合酶类/遗传学指导DNA的RNA聚合酶类/代谢诱变植物蛋白质类/遗传学植物蛋白质类/代谢植物芽/化学植物芽/超微结构植物有毒质体/酶学质体/超微结构烟草/酶学烟草/遗传学

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CYTOPLASMIC AND OUTER MEMBRANES SEPARATION IN RHODOPSEUDOMONAS-SPHAEROIDES

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ARCHIVES OF MICROBIOLOGY 1975年第3期105卷 269-275页

作者： GUILLOTIN, J REISSHUSSON, F CNRS LAB PHOTOSYNTH F-91190 GIF SUR YVETTE FRANCE

A cell envelope fraction had been prepared after mechanical disruption of lysozyme-EDTA spheroplasts from depigmented Rhodopseudomonas sphaeroides (aerobically grown in the light). On linear sucrose gradients this fraction can be separated in a cytoplasmic membrane fraction and an outer membrane fraction. The cytoplasmic fraction (buoyant density: 1.18 g/cm3) has been characterized by its succinic dehydrogenase activity and by its composition. The outer membrane fraction (buoyant density: 1.21 g/cm3) does not contain any respiratory activity nor hemoproteins. The same fractionation has been done on cells repigmented in the dark by lowering the O2 pressure. In that case the same two fractions have been detected in addition to the chromatophore fraction (buoyant density: 1.14 g/cm3). However both, and specially the outer membrane fraction, were contaminated by chromatophore material.

关键词：需氧生活细菌载色体细菌叶绿素类/分析类胡萝卜素类/分析细胞分级分离/方法细胞壁/分析离心法梯密度黑暗血红素蛋白类/分析膜/分析氧分压光合作用红杆菌球形/细胞学球粒体/分析琥珀酸脱氢酶/分析泛醌/分析

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