66 research outputs found

    Study and exploitation of Meretrix meretrix Linnaeus polypeptide health product

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    文蛤(MeretrixmeretrixLinnaeus)具有很高的营养价值和药用价值,其食用的营养价值之高和用途之广居各种贝类之首被誉为”天下第一鲜”。本文通过六种蛋白酶酶解文蛤蛋白的产物比较、成分分析和生理功能研究,以期获得具有质量稳定、颜色风味俱佳、多肽分子量小含量高、生理功能丰富的文蛤多肽保健品。 本文以酶解后产物中的游离氨基酸含量的多寡即降解度为标准,研究了菠萝蛋白酶、木瓜蛋白酶、复合胰蛋白酶、胰蛋白酶、中性蛋白酶和碱性蛋白酶六种蛋白酶各自酶解文蛤的pH、温度、酶量和时间等条件,发现它们酶解文蛤的最适pH依次为6.5,7.0,8.0,8.0,7.0,8.0;最适酶解温度除了菠萝蛋白酶...Meretrix meretrix Linnaeus has high nutrition value and medicine value, its edible nutrition value and usage is the best in all kinds of seashells and is honored as “the most delicious food in the world”. By comparing the product of 6 proteinases hydrolyzing and studying the product biology functions, in this paper we try to get Meretrix meretrix Linnaeus health care product with stable quality, g...学位:理学硕士院系专业:生命科学学院生物化学与生物技术系_生物化学与分子生物学学号:20042611

    中国与世界金融市场从分割走向整合——基于DCC-MGARCH模型的检验

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    本文结合我国金融自由化进程的变化轨迹和沿革路径,构建了中国金融自由化指数;采用非对称M-GARCH模型,并应用Engle提出的动态条件相关方法(DCC)捕捉资产价格的动态相关系数。在此基础上,通过对中国与亚洲、欧美7个重要的资本市场从1991~2008年18个年份的实证分析,我们发现,伴随着中国金融自由化政策的渐近推进和逐步深化,中国与这些市场的联动性越来越强,中国证券市场从最初的、相对独立的分割状态逐渐走向日益紧密的全球整合

    没食子酸衍生物对蘑菇酪氨酸酶的抑制机理

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    蘑菇褐变过程主要是由于其酪氨酸酶的催化作用引起的,寻找该酶抑制剂在食品保鲜和储藏中的应用具有重要的意义.作者在实验中,发现没食子酸十二烷基酯和没食子酸香叶酯对蘑菇酪氨酸酶有较强的抑制作用,测定它们抑制蘑菇酪氨酸酶二酚酶的酶活力下降50%的抑制剂浓度(IC50)分别为1.55和0.25 mmol/L.显示没食子酸香叶酯的抑制作用强度是没食子酸十二烷基酯的6倍.研究了这两种抑制剂对蘑菇酪氨酸酶的抑制作用动力学,结果表明:没食子酸十二烷基酯和没食子酸香叶酯对酶的抑制作用均表现为可逆反应,前者为反竞争性,其抑制常数KIS为0.636 mmol/L;而后者为混合型,抑制常数KI和KIS分别为0.133和0.453 mmol/L

    南瓜粉的酶法制备及营养成分分析

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    用菠萝蛋白酶对南瓜进行酶解,研制生产南瓜粉,实验结果表明:0.04%菠萝蛋白酶pH 6.35条件下,50℃酶解5h为最佳酶解条件.并对南瓜粉进行成分分析,其水分、灰分、脂肪、糖类物质、蛋白质、果胶含量分别为8.34%,5.61%,0.41%,58.46%,13.24%,1.82%.另外比较了南瓜粉与灵芝粉和莲子粉中的一些金素元素含量.研究结果为南瓜中有效营养成分的提取和开发利用提供了科学依据

    Photoreduction of Se(Ⅵ) by Marine Algae-Transitional Metals-Light System

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    以海洋绿藻(Tetraselmislevis,Chlorellaautotrophica,Dunaliellasalina,Nannochloropsissp.,Tetraselmissubcordi-formis)、硅藻(Phaeodactylumtricornutum)、红藻(Porphyridiumpurpureum)和过渡金属(铁、锰、铜)构建海藻-光二元体系、过渡金属-光二元体系、海藻-过渡金属-光三元体系,对比分析不同海藻、不同过渡金属、海藻与过渡金属耦合引发光化学过程,对Se(Ⅵ)还原转化的贡献率.二元和三元体系均可光还原转化Se(Ⅵ)为Se(Ⅳ).铁、铜、锰通过自身的光氧化还原过程诱发Se(Ⅵ)/Se(Ⅳ)的氧化还原;海藻的光化学活性首次被证实,表面壁可吸附富集海水中还原性的有机物、Se(Ⅵ)/Se(Ⅳ)和过渡金属,改变其氧化还原电位,提供光反应场所;Se(Ⅵ)的光还原转化率依海藻和过渡金属的种类、浓度不同而异;海藻浓度的提高、海藻与过渡金属的耦合作用有利于光还原转化率的提高.通过三元体系的光还原转化,Se(Ⅵ)/Se(Ⅳ)比值为1·17~2·85,接近海洋真光层Se(Ⅵ)/Se(Ⅳ)实际浓度比,即海藻和过渡金属引发的光化学过程对硒的价态分布起决定性作用.Seven marine phytoplankton, including five green algae (Tetraselmis levis, Chlorella autotrophica, Dunaliella salina, Nannochloropsis sp. and Tetraselmis subcordiformis), one diatom (Phaeodactylum tricornutum), one red alga (Porphyridium purpureum), and three usual transitional metals (Fe(Ⅲ), Cu(Ⅱ), Mn(Ⅱ)) were used to make up marine phytoplankton-light or transitional metals-light or marine phytoplankton-transitional metals-light system. In such system, Se(Ⅵ) could be transformed into Se(Ⅳ) by photoreduction. The species transformation of selenium could be photo-induced by redox reaction of transitional metals. The photochemical activity of marine phytoplankton was confirmed for the first time, because marine phytoplankton could adsorb and concentrated of selenium, transitional metals and organic substances (including the exudation of algae, as reducing agent) which redox potentials were changed. The ratios of Se(Ⅵ) to Se(Ⅳ) were dominated by the species, the concentration of marine phytoplankton and transitional metals, and it could be enhanced through increasing the concentration of marine algae or the combined effect from marine algae and transitional metals. After photoreduction by ternary system, the ratio of Se(Ⅵ) to Se(Ⅳ) ranges from 1.17 to 2.85, which is close to the actual value in euphotic layer of seawater. The photochemical process that is induced by marine algae and transitional metals dominative the leading effects on the distribution of oxidation states of selenium.国家自然科学基金资助项目(40131160735);; 福建省科技三项费用项目(K02093);; 福建省青年科技人才创新项目(2003J035);; 福建省教育厅A类项目(JA00233

    水杨酸的抑酶与抑菌作用

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    以水杨酸为效应物,研究其酶学效应和微生物效应.实验结果表明:水杨酸对马铃薯多酚氧化酶有明显的抑制作用,半抑制率(IC50)为2.05 mmol/L,抑制作用表现为非竞争性的可逆过程,其抑制常数为2.00 mmol/L.水杨酸对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌3种细菌和白色假丝酵母、黑曲霉两种真菌均有明显的抑制作用,其最小抑菌浓度(M IC)分别为0.75、0.5、0.5、0.25和0.75 mg/mL,最小杀菌浓度(MBC)分别为0.75、1.0、0.5、0.25和0.75 mg/mL.本研究为水杨酸在果蔬保鲜中的应用提供实验理论依据

    P TYPE GRADIENT ENHANCED DQF COSY EXPERIMENTS SHOW LOWER t 1 NOISE THAN N TYPE *

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    脉冲相位的不稳定性是导致二维谱中的T1噪声的原因之一.本文从理论上和实验上对脉冲相位不稳定性所引起的T1噪声进行了研究.从角动量算符IX,Iy和Iz推导中发现,由于磁化矢量在P型和n型dQfCOSy实验的脉冲梯度场中进动方向的内在差异,一部分脉冲相位误差在P型dQfCOSy实验会被重聚掉,在n型dQfCOSy实验中却会被加重.因此P型dQfCOSy实验的T1噪声比n型小.理论推导还得到T1噪声在P型和n型中的理论比值为3∶11.以上理论结果得到我们实验结果的支持t 1 noise, stemming from the instabilities of pulse phases in 2D spectroscopy, has been investigated theoretically as well as experimentally.Based on the angular momentum operator I x,I y,I z formalism, our deductions show that the different precessing directions of the magnetization between P type and N type gradient enhanced DQF COSY experiments result in that P type gradient enhanced DQF COSY experiments refocus the phase errors of pulses, while N type gradient enhanced DQF COSY experiments strengthen the effect of the phase errors of pulses.Therefore, t 1 noise in P type gradient enhanced DQF COSY experiments is lower than that in N type.In addition, the theoretical ratio of P type to N type is 3∶11, which is supported by our experimental results

    文蛤多肽粉对人肝癌细胞SMMC-7721的抑制作用及免疫调节作用

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    将文蛤肉以复合胰蛋白酶酶解,经喷雾干燥工艺得到了文蛤多肽粉,研究文蛤多肽粉对肝癌细胞的抑制作用和对昆明种小鼠的急性毒理作用和免疫调节作用,结果显示文蛤多肽粉对体外培养的肝癌细胞SMMC-7721具有明显的杀伤作用,使细胞变形以至破裂从而抑制癌细胞的生长,抗肿瘤作用明显;文蛤多肽粉给药组的胸腺指数和脾脏指数较空白对照组明显升高,提示文蛤多肽粉能促进小鼠胸腺和脾脏的生长发育,增强免疫力

    闽南文化研究国际笔谈会论点选载

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    2013年12月21日,由闽南师范大学闽南文化研究院主办的“2013闽南文化研究国际笔谈会“在国际学术交流中心召开。来自海峡两岸及日本、新加坡等国家的闽南文化研究方面的专家、学者二十余人出席了会议。会议围绕着闽南文化的内涵、外延及特征,闽南文化的当代价值与社会功能,闽南文化研究的理论与方法,闽南文化的跨文化阐释,闽南文化的世界性及其意义,闽南文化与两岸交流,闽南文化的生态保护,闽南文化学科建设与人才培养等议题展开了深入的研讨,言简意赅,探幽发微,对当下闽南文化理论研究势必产生积极的影响。本期节录专家们的精彩发言,以飨读者,也希望由此来带动和促进闽南文化研究的进一步升华

    Economic Integration and Stock Market Linkages:Analysis of the data based on relevant experience

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    作为一个兼具经济一体化和股市快速发展双重特征的经济体,中国可以作为一个很好的研究样本来考察经济一体化与股市联动性二者之间的动态关系。运用多元GARCH模型和向量自回归模型剖析经济一体化对股市联动性所起的作用,结果表明,在1991至2007的17个年份中,在中国经济一体化进程的推进下,中国、美国和中国香港三地股市的联动性越来越强,中国证券市场日益溶入全球资本市场。进一步的研究还发现,金融自由化、贸易自由化和经济趋同化三个维度对股市联动性的影响具有差异性。Abstract:China, as an economy characterized by both economic integration and rapid development of stock markets, is an ideal sample for the study of dynamic relations between economic integration and stock market linkages. Looking into the impact of economic integration on stock market linkages through GARCH modeling and vector autoregression modeling, we conclude that during the 17 years between 1991 and 2007, with the impetus provided by China. s economic integration, linkages between stock markets in China, the USA and Hong Kong have become stronger and that China. s stock markets are increasingly integrated into the global capital market. Our evidence also confirms that three dimensions, i. e. financial liberalization, trade liberalization and economic convergence, influence stock market linkages differently.国家自然科学基金重点项目“公司财务管理若干基础问题研究”(70632001);国家统计科学研究计划项目“经济一体化统计测度及其对金融危机传染影响研究”(2009LY087
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