外源咖啡酸和阿魏酸对黑莓汁中花色苷的辅色研究

为增强黑莓汁中花色苷的稳定,添加适量咖啡酸和阿魏酸到黑莓清汁中,采用可见吸收光谱和高效液相色谱-质谱研究其对黑莓花色苷的辅色作用。研究结果表明:黑莓汁中添加咖啡酸和阿魏酸显著增加了花色苷的最大吸收值(Aλmax),最大吸收波长(λmax)红移,说明咖啡酸和阿魏酸对黑莓汁中花色苷产生了辅色作用,辅色效应随时间的延长和咖啡酸、阿魏酸浓度的增加显著增强。HPLC-DAD-MS分析发现,咖啡酸辅色产生了两种新的花色苷衍生物(矢车菊素-3-O-葡萄糖苷-4-乙烯基儿茶酚和矢车菊-3-O-草酸酐酰葡萄糖苷-4-乙烯基儿茶酚),阿魏酸辅色产生了三种新的花色苷衍生物(矢车菊素-3-O-葡萄糖苷-4-乙烯基愈创木酚、矢车菊-3-O-草酸酐酰葡萄糖苷-4-乙烯基愈创木酚和矢车菊-3-O-阿拉伯糖苷-4-乙烯基愈创木酚),这些衍生物均为羟苯基-吡喃花色苷。     

当归不同提取液中阿魏酸、咖啡酸含量及抗氧化作用的比较研究北大核心CSCD

为考察不同提取条件对当归提取液中阿魏酸和咖啡酸的含量及抗氧化作用的影响,本研究通过HPLC外标一点法检测当归提取液中阿魏酸和咖啡酸的含量,通过DPPH法和ABTS法检测当归提取液的抗氧化作用。研究结果表明,不同提取条件下当归提取液中阿魏酸的含量为0. 574～0. 707 mg/g,咖啡酸为0. 012～0. 082 mg/g;碱水溶液提取时阿魏酸与咖啡酸的含量最高,其抗氧化活性也最强,而95%乙醇提取时的含量最低,抗氧化活性最弱;提取溶剂随醇浓度的增加,咖啡酸的含量逐渐减少,阿魏酸的含量呈现先增加后减少的趋势,30%～50%乙醇提取时各组分有良好的协同抗氧化作用。     

肉桂酸和咖啡酸对莴苣生长的化感作用及其机理研究

该研究以莴苣为受体植物,分析了酚酸类化感物质肉桂酸和咖啡酸对莴苣幼苗生长的活性效应及其作用机理,以揭示酚酸类化合物的化感作用机制。结果显示:(1)不同浓度的肉桂酸均对莴苣幼苗根长、茎长及鲜重产生明显的抑制作用,当肉桂酸的浓度为1 000μmol/L时其对莴苣幼苗根长、茎长及鲜重的抑制率分别达到了89%、74%和49%;咖啡酸对莴苣幼苗根长和茎长均表现出低浓度(0.1、1.0和10μmol/L)促进、高浓度(100和1 000μmol/L)抑制的活性作用模式,且高浓度下肉桂酸对幼苗生长的抑制作用明显强于咖啡酸。(2)较低浓度(0.1、1.0和10μmol/L)的肉桂酸和咖啡酸对莴苣根尖细胞活力均无明显影响;高浓度(100和1 000μmol/L)的肉桂酸和咖啡酸使莴苣根尖细胞的死亡数明显增加。(3)低浓度(0.1和1.0μmol/L)的肉桂酸和较低浓度(0.1、1.0和10μmol/L)的咖啡酸对莴苣根部的活性氧积累均无明显影响;当肉桂酸处理浓度大于10μmol/L及咖啡酸处理浓度大于100μmol/L时,随着浓度的升高莴苣根部活性氧的积累大量增加。研究表明,一定浓度的肉桂酸和咖啡酸均能够诱导莴苣体内活性氧的产生和积累,并降低幼苗根尖细胞的活力,进而影响莴苣幼苗的生长发育,且肉桂酸的生长抑制作用明显强于咖啡酸。     

咖啡酸代谢物的抗肾炎活性分析

在研究治疗肾功能紊乱植物的细胞培养时, 建立了一个Eritrichium sericeum的E-4愈伤组织株系, 发现此株系可产生大量的咖啡酸代谢物、(–)-rabdosiin (1.8%干重)和迷迭香酸(4.6%干重), 通过诱导(–)-rabdosiin的含量提高至4.1% (干重)。将E-4愈伤组织喂服Masugi肾炎大鼠, 结果发现, 与对照组(未喂服E-4愈伤组织的Masugi肾炎大鼠)相比, 处理组(喂服E-4愈伤组织)中的大鼠出现如下症状: 尿多、排泄物中肌氨酸酐降低、尿蛋白水平降低; 当对照组中所有大鼠都出现疼痛症状时, 处理组中仍有约/4的大鼠表现出健康状况良好。以上结果表明, E-4株系具有缓解肾炎症状的潜在功能。此外, 利用富含多酚的rolC转基因的细胞株系, 研究了愈伤组织中咖啡酸代谢物的诱导合成机制。结果发现,在rloC转基因的E. sericeum愈伤组织中,咖啡酸代谢物的高产与迷迭香酸生物合成中的关键基因CYP98A3的高表达有关。     

微生物异源合成咖啡酸及其酯类衍生物研究进展 *

咖啡酸及其酯类衍生物如绿原酸、迷迭香酸和咖啡酸苯乙酯等具有天然抗氧化、抗肿瘤、抗病毒和抗炎等重要的药理活性,具有广阔的药用开发前景。从天然药物中提取或者化学合成咖啡酸及其酯类衍生物,存在含量低、提取效率不高、催化成本高昂以及环境污染等问题。随着咖啡酸及其酯类衍生物合成途径解析和合成生物学的快速发展,微生物异源合成咖啡酸及其酯类衍生物的研究已逐渐展开。对微生物异源合成咖啡酸及其酯类衍生物合成途径的最新进展以及代谢工程策略进行了综述,并讨论了目前存在的问题和未来的发展趋势。     

川芎晒干过程中阿魏酸和阿魏酸松柏酯含量的变化

为了解新鲜川芎采后干燥过程中阿魏酸和阿魏酸松柏酯含量的动态变化规律,采用高效液相色谱法测定了川芎晒干过程中总阿魏酸、游离阿魏酸和阿魏酸松柏酯的含量。结果显示,在整个晒干过程中(30 d),总阿魏酸、游离阿魏酸和阿魏酸松柏酯含量呈先升高后下降的变化趋势,晾晒第3 d时总阿魏酸含量最高(0.23%),因此在晾晒的第3 d利用快速干燥技术能较好地保留川芎药材中总阿魏酸含量,使其发挥更佳的药效。川芎药材中的阿魏酸松柏酯能水解产生阿魏酸,因此研究川芎干燥过程中的生理响应与含水量的关系对阿魏酸积累有重要意义。由于川芎在用药过程中是以总阿魏酸含量发挥药效的,所以以总阿魏酸含量作为川芎药材质量控制指标更加科学。     

蜂胶中提取的咖啡酸苯乙酯和咖啡酸苄酯抑制食管癌Eca109细胞的功效

本文研究了蜂胶中两种主要组分咖啡酸苯乙酯(CAPE)和咖啡酸苄酯(CABE)对食管癌Eca109细胞的抑制功效及初步作用机理。通过SRB法检测了细胞存活率;划痕法结合Transwell实验检测对Eca109细胞迁移和浸润的影响;DAPI染色结合Western blotting检测了对Eca109细胞凋亡和凋亡执行者Caspase 3和PARP蛋白表达的影响;通过两种荧光探针分别检测了对细胞内活性氧(ROS)和线粒体膜电位(MMP)的影响。结果表明,CAPE和CABE能够显著抑制Eca109细胞增殖,诱导其凋亡,上调Caspase 3和PARP的水平,同时CAPE和CABE显著上调ROS水平并降低MMP水平。说明CAPE和CABE是两种有潜力的治疗食管癌的天然产物。     

咖啡酸抗人乳头瘤病毒感染的研究

宫颈癌(Cervical cancer,CC)是妇科最常见的恶性肿瘤之一,而高危型人乳头瘤病毒(Human papillomavirus,HPV)的持续感染是诱导宫颈癌发生的重要危险因素。目前全球抗HPV药物极为匮乏,寻找新的高效、低毒、价廉的广谱抗病毒药物对HPV感染的防治至关重要。本文研究发现,咖啡酸(Caffeic acid,CA)能有效抑制三株不同亚型的HPV感染(HPV-6、HPV-16及HPV-18),其半数抑制浓度在12.1～16.5μg/mL之间。Time-of-addition结果证实,咖啡酸对病毒进入靶细胞的早期阶段具有一定抑制作用。Temperature shift实验发现,咖啡酸能一定程度抑制HPV病毒颗粒黏附于靶细胞表面。表面等离子共振分析表明,咖啡酸与HPV-16型病毒的主要衣壳蛋白L1具有极强的结合力。综上,咖啡酸具有较高的抗HPV活性,其作用机制可能是与病毒衣壳蛋白L1结合,从而阻止病毒黏附并进入靶细胞。咖啡酸具有安全、价廉、易得等优势,有望被开发成新型的抗HPV病毒感染的抑制剂,因其尚能同时抵抗多种性传播性病毒的感染,对HPV并发的多种性传播性疾病具有较好的预防作用,应用前景广泛。     

咖啡酸对慢性铝负荷大鼠肝损伤的保护作用

目的 观察5-脂氧酶(5-LO)抑制剂咖啡酸对慢性铝负荷所致大鼠肝损伤的保护作用,并初步探讨其可能的机制。方法 将SD大鼠分为空白对照组、慢性铝负荷模型组、咖啡酸低剂量组和咖啡酸高剂量组,除空白对照组外,每组大鼠每天灌胃给予葡萄糖酸铝(Al3+ 200 mg·kg-1·d-1),给药组大鼠在给铝后1周分别灌胃给予2个剂量的咖啡酸,每周5 d,连续20周。建模完成后,用生化法检测大鼠血清中丙氨酸氨基转移酶(ALT),天门冬氨酸氨基转移酶(AST)和碱性磷酸酶(ALP)活性,以及肝组织丙二醛(MDA)含量,超氧化物歧化酶(SOD)活性,采用苏木精-伊红染色法观察大鼠肝脏组织形态学变化,用免疫组织化学法检测大鼠肝组织5-LO蛋白表达情况。结果 与空白对照组大鼠比较,慢性铝负荷模型组大鼠血清ALT、AST、ALP活性显著升高,肝组织MDA含量显著增加,SOD活性显著下降,肝细胞出现明显空泡性变、点状坏死、肝细胞排列紊乱,肝组织5-LO在血管周围肝细胞胞浆中表达明显。与铝负荷模型组比较,给予咖啡酸后大鼠肝细胞损伤减轻,血清ALT、AST、ALP活性明显降低,肝组织MDA含量显著减少,SOD活性显著上升,肝组织5-LO表达明显减少。结论 咖啡酸能减轻慢性铝负荷所致肝损伤,机制可能与其抑制5-LO表达、减轻氧化应激反应损伤有关。     

组胺H_1受体激动剂PEA抑制胃酸分泌效应的中枢机制

本文分析了中枢注射ＰＥＡ抑制胃酸分泌效应的脑内过程。雄性Ｗｉｓｔａｒ大鼠,摘除双侧肾上腺,用３７℃的生理盐水通过恒流泵进行连续胃液流。第三脑室给药,观察其对五肽促胃液素（１６０μｇ／ｋｇ,ｓ．ｃ．）诱导的胃酸分泌的影响。结果如下：（１）预先脑室注射抗ＣＲＦ血清（２．５μｌ,１：２００００）可阻断１ＯμｇＰＥＡ的中枢抑酸效应;（２）分别脑室给予ＣＲＦ（１．０和２．０μｇ）和β－内啡肽（０．９４和１．２５μｇ）均明显抑制胃酸分泌;（３）预先注射纳洛酮（５．０μｇ,ｉ,ｃ．ｖ,）可取消ＣＲＦ（１．０μｇ）的中枢抑酸效应,而预先注射抗ＣＲＦ血清（２．５μｌ）对β－内啡肽（０．９４μｇ）的中枢抑酸效应无明显影响。结果提示：ＰＥＡ可能首先引起ＣＲＦ释放,后者再刺激内源性阿片肽释放,从而导致迷走介导的胃酸分泌抑制效应。     

脑室注射组胺H1受体激动剂对大鼠胃酸分泌的作用机制

本文对中枢注射ＰＥＡ抑制胃酸分泌的作用机制进行分析。雄性Ｗｉｓｔａｒ大鼠,重２００－３００ｇ,用３７（生理盐水通过恒流泵进行连续胃灌流。第三脑室给药,观察其对五促胃液素（１６０μｇ／ｋｇ,ｓ．ｃ．）诱导的胃酸分泌的影响。结果如下：（１）预先注射纳洛酮２．５μｇ可阻断１０μｇＰＥＡ的中枢抑酸效应;（２）双侧膈下迷走神经切除可翻转ＰＥＡ（５－２０μｇ）的抑酸效应,且有量效关系;双侧肾上腺摘除对ＰＥＡ中     

EFFECTS OF SINGLE AND MULTIPLE EXPOSURES OF FERULIC ACID ON THE VEGETATIVE AND REPRODUCTIVE GROWTH OF PHASEOLUS VULGARIS BBL-290

Phaseolus vulgaris BBL-290 plants were grown in growth chambers in the Southeastern Plant Environment Laboratory and exposed to either single (at seedling, flower, or podfill) or multiple (biweekly or weekly) treatments of ferulic acid (FA). In the first experiment, plants were harvested one week after FA treatment (0, 1.0, 2.0 mM) and at final harvest (56 days old). FA delayed leaf expansion during the seedling and flowering stages. The total plant leaf area and the plant dry weight of plants treated with 1.0 and 2.0 mM FA as seedlings were reduced one week after treatment by 38–48%. The total plant leaf area and the plant dry weight of plants treated at flowering with 2.0 mM FA were reduced by 25% one week after treatment. Treatment with 2.0 mM FA at podfill caused the senescence and abscission of older leaves and reduced total plant leaf area, plant dry weight and mean pod dry weight by 54, 40, and 48%, respectively, one week after treatment. The plants treated at the seedling and flowering stages recovered by final harvest. In a subsequent experiment, FA (0, 0.50, 1.0, 1.5 mM) reduced total plant leaf area at the seedling and flowering stages but not at podfill. The youngest expanding leaves were most sensitive to FA at flowering. The leaf area of these leaves was reduced by 35 and 25%, one and two weeks after treatment, respectively. Their absolute growth rates were reduced from 31 to 56% one week after treatment at flowering. Their relative growth rates were reduced by 50% one week after treatment. Growth rates then recovered within two weeks after treatment. In the final experiment, biweekly exposures of FA (0.25, 0.50, 0.75, 1.0) reduced total plant leaf area but did not affect any other growth parameters. Weekly exposures of FA (0.25, 0.50, 0.75, 1.0) reduced total plant leaf area up to 34%, absolute growth rate up to 58%, leaf number up to 31% and pod number up to 58%. As the frequency of exposure to FA increased, the concentration necessary to affect bean plant growth and development decreased.     

DISAGGREGATION OF BRAIN POLYSOMES AFTER d-LYSERGIC ACID DIETHYLAMIDE ADMINISTRATION IN VIVO: MECHANISM AND EFFECT OF AGE AND ENVIRONMENT1

Abstract— The cell-free protein synthesis activity and tRNA content of the increased pool of brain monosomes produced after d -lysergic acid diethylamide (LSD) administration were analyzed. Decreased reinitiation of protein synthesis rather than RNase activation or premature termination was shown to be the mechanism which results in brain polysome disaggregation after administration of the drug in vivo. At a constant dosage of 50 μg/kg the degree of polysome shift increases with age from 3-week-old rabbits to adults. There is also an extensive disaggregation of fetal brain polysomes when LSD is administered maternally. The LSD-induced polysome shift was shown to be altered by holding cage environment, pre-LSD sedation and post-LSD handling with brief restraint. It was apparent that elements of environment and physiological arousal were involved in the macromolecular effect of the drug on the protein synthesis apparatus of the brain.     

THE EFFECT OF TEMPERATURE ON L-LACTIC ACID PRODUCTION AND METABOLITE DISTRIBUTION OF Lactobacillus casei

The effect of temperature on the growth and L-lactic acid production of Lactobacillus casei G-03 was investigated in a 7-L bioreactor. It was found that the maximum specific growth rate (0.27 hr^?1) and L-lactic acid concentration (160.2 g L^?1) were obtained at a temperature of 41°C. Meanwhile, the maximum L-lactic acid yield, productivity, and dry cell weight were up to 94.1%, 4.44 g L^?1 hr^?1, and 4.30 g L^?1, respectively. At lower or higher temperature, the Lactobacillus casei G-03 showed lower acid production and biomass. Moreover, the main metabolite distribution of strain G-03 response to variations in temperatures was studied. The results suggested that temperature has a remarkable effect on metabolite distribution, and the maximum carbon flux toward lactic acid at the pyruvate node was obtained at 41°C, which had the minimum carbon flux toward acetic acid.     

激光所致核酸损伤的分子机制

本文综述了近来有关紫外激光诱导核酸损伤(主要是碱基损伤、单链断裂和双链断裂)形成的化学过程的文献报导,主要是讨论了双光子激发核酸碱基,致使核酸产生单链断裂和双链断裂的光致电离过程,以及由此归纳出来的激光诱导核酸链断裂的化学模型     

EFFECT OF INDOLE-3-ACETIC ACID,KINETIN, AND ETHYLENEDIAMINETETRAACETIC ACID ON PLANT GROWTH AND UPTAKE AND TRANSLOCATION OF LEAD,MICRONUTRIENTS, AND MACRONUTRIENTS IN ALFALFA PLANTS

Alfalfa plants germinated and grown for 15 d in soil containing 80 mg Pb kg^?1 were treated with ethylenediaminetetraacetic acid (EDTA) at 0.8 mM and indole-3-acetic acid-kinetin (IAA-KN) at 100 μM. Fifteen days after the treatment application, the concentration of lead (Pb), macronutrients, and micronutrients was determined using inductively coupled plasma/optical emission spectroscopy. The chlorophyll content and plant growth were also measured. Roots of plants exposed to Pb alone, Pb–EDTA, and Pb–EDTA-IAA-KN had 160, 140, and 150 mg Pb kg^?1 DW, respectively. Pb was not detected in the stems of plants exposed to Pb alone; however, stems of plants treated with EDTA and EDTA–IAA-KN had 78 and 142 mg Pb kg^?1 DW, respectively. While the Pb concentration in leaves of plants treated with EDTA and EDTA–IAA-KN was 92 and 127 mg kg^?1 DW, respectively. In addition, EDTA and EDTA–IAA-KN significantly increased the translocation of zinc and manganese to leaves. The x-ray absorption spectroscopic studies demonstrated that Pb(II) was transported from roots to leaves without a change in the oxidation state.     

东莨菪碱抑制呼吸效应及其机制

本文给兔侧脑室、犬椎动脉以及静脉注射东莨菪碱,从呼吸频率、潮气量、通气量及血气分析多项指标皆观察到东莨菪碱有明显抑制作用,且存在剂量依赖关系。东茛菪碱尚能拮抗毛果靶香碱的呼吸效应,但不能拮抗６β－乙酰氧基去甲托烷呼吸抑制效庆,反而起协同作用。上述结果提示示东莨菪碱引起呼吸抑制可能与民呼吸中枢Ｍ１受体有关。     

INFLUENCE OF FERULIC ACID ON MINERAL DEPLETION AND UPTAKE OF 86Rb BY PAUL'S SCARLET ROSE CELL-SUSPENSION CULTURES

The influence of 10^-4 m ferulic acid on mineral depletion and ion uptake in sterile cultures of Paul's Scarlet rose was examined. The effect of ferulic acid on the rate of depletion of Mg²⁺, Ca²⁺, K⁺, P, Fe³⁺, Mn²⁺, and Mo³⁺ from the medium during the 14-day growth cycle varied with the age of the cells and the ion under consideration. In general, rates of uptake were higher than control rates in older cells and less than control rates in cells 3–5 days old. The degree of inhibition of uptake of ⁸⁶Rb also varied with age. Young (4–5 day) cells showed approximately 50% inhibition at high concentrations of RbCl (system 2) and approximately 25% inhibition at low concentrations of RbCl (system 1). In contrast, the rate of ⁸⁶Rb uptake in 10-day cells was not significantly altered by incubation in ferulic acid.