低聚原花青素对草莓色素的抗氧化活性研究

草莓红色素属花色苷类化合物,在酸性条件下相对稳定,光、热对色素具有一定的降解作用.本文采用60%的乙醇溶液从葡萄籽中提取出天然抗氧化剂低聚原花青素,研究了它对草莓色素的抗氧化活性.结果表明,低聚原花青素能抑制草莓色素的氧化降解,具有明显的护色作用,同时还可起到防腐效果.     

几种天然花色苷色素稳定性的比较与分析

比较了几种天然花色苷色素的稳定性 ,用纸层析法分离了这几种色素 ,得出了每种色素所含主要花色苷数量。讨论了花色苷种类多少对色素稳定性的影响。实验研究表明 ,色素所含花色苷种类越多 ,色素稳定性越高     

几种天然花色苷素稳定性的比较与分析

比较了几种天然花色苷色的稳定性，用纸层析法分离了这几种色素，得出了每种色素所含主要花色苷数量，讨论了花色苷种类多少对色素稳定性的影响。实验表明，色素所含花色苷种类越多，色素稳定性越高。     

体外模拟人肠道微生物对葡萄酒花色苷稳定性的影响

分析肠道微生物对葡萄酒花色苷稳定性的影响及花色苷结构与稳定性的关系,旨在为花色苷的消化吸收和提高葡萄酒花色苷生物利用率提供指导。采集健康受试者的肠道微生物,利用体外培养方法混合培养肠道微生物与赤霞珠红葡萄酒样品24h,分别于0、4、12、24h取样进行花色苷的高效液相色谱分析。结果表明,肠道微生物促进葡萄酒花色苷的降解。与肠道微生物共培养24h后,葡萄酒总花色苷的降解率达到19.10%,而对照组仅为9.57%;肠道微生物作用下,葡萄酒中5种基本花色苷的降解水平均高于无菌对照组,但不同处理间没有显著差异;对比无菌对照组,葡萄酒中3种酰化花色苷含量在肠道菌群的作用下显著降低。花色苷B环取代基与酰基种类影响花色苷的稳定性。B环羟基数量增加,花色苷稳定性下降;B环甲氧基数量增加,花色苷稳定性增强。乙酰化花色苷稳定性强于对香豆酰化花色苷。肠道微生物对葡萄酒花色苷降解的促进作用与花色苷结构有关。     

一种优质的食用天然色素—萝卜红花色苷的性质研究

从红心萝卜中提取、精制得到紫红色的萝卜红花色苷色素。色素易溶于水、甲醇、乙醇等极性溶剂;色素在pH值为1．0～6．0范围内保持稳定,呈鲜艳的红色;随pH值的升高色素的稳定性下降;温度对色素的稳定性影响显著,温度超过60℃时,色素的稳定性迅速降低;色素对日光照射敏感,连续照射25d后色素的保留率为82%;分别在－18℃、4℃、20℃、37℃下贮藏15周,色素几乎没有降解,表现出良好的贮藏稳定性。萝卜红花色苷在canola油中有较强的抗氧化性。     

花色苷类物质化学成分及抗衰老机制研究进展

花色苷作为一种功能性天然食用色素,在天然保健品及功能性食品中具有广泛的应用前景.文章对花色苷类物质的种类、成分、抗氧化活性、抗衰老能力及药理学研究进行综述,并重点对其抗衰老作用及机制提出展望.     

食用植物中花色苷研究

植物食物中的花色苷是一类水溶性色素,属类黄酮化合物,近年研究表明具有抗氧化、抗突变肿瘤、防治心血管疾病、抗炎等多种生理功能.对花色苷生理活性及部分作用机制进行了综述.     

植物花色苷的提取和鉴定研究

植物中的花色苷作为一种天然色素,具有重要的生物活性．文章对花色苷种类、提取分离和鉴定及其稳定性等方面的研究进行综述．     

龙陵紫皮石斛花色苷色素抑菌作用初探

以龙陵紫皮石斛(Dendrobium devonianum)紫茎为试材,研究其色素的抑菌作用。用溶剂法提取花色苷,通过固体和液体培养基的试验方法,研究了龙陵紫皮石斛花色苷对大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphyloccocus aureus)、枯草芽孢杆菌(Bacillus subtilis)的抑菌作用。3种类型紫皮石斛花色苷对枯草芽孢杆菌抑菌作用较为显著,且抑菌作用与花色苷浓度呈正相关。抑菌作用大小为:枯草芽孢杆菌金黄色葡萄球菌大肠杆菌。     

矮牵牛花色素成分的初步分析

以矮牵牛梦幻系列不同花色为试验材料,进行了特征显色反应和紫外-可见光谱扫描分析。结果表明:矮牵牛不同花色的色素由类黄酮和类胡萝卜素两大类组成,不含有查耳酮、橙酮、儿茶素等;淡粉红色和粉红色花含有花色苷及黄酮类化合物,红色、紫红色、紫青色和鲑红色矮牵牛的色素主要由花色苷、黄酮类化合物和类胡萝卜素组成。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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