多花野牡丹红色素的提取及其稳定性研究

本文对多花野牡丹（Melastoma affine）果实胎座的色素进行了理化性质的探讨,对光、温度、氧化还原介质、7种金属离子、葡萄糖、蔗糖、苯甲酸钠对色素稳定性的影响进行了研究。结果表明,该色素为水溶性花青苷类色素,它在60 ℃以下稳定性较好,对光的耐受性较差。色素在酸性条件下稳定性好,耐还原性也较好,但耐氧化性较差。7种金属离子中,Fe3+、Cu2+、Mn2+、Zn2+对色素有明显降解作用,而Na+、Mg2+、Al3+对色素稳定性较好并有不同程度的护色作用。葡萄糖、蔗糖、苯甲酸钠对色素无不良影响。     

木莓果实红色素的理化性质及其稳定性

对木莓（Rubus swinhoei Hance)果实中提取的红色素理化性质进行了探讨,并就光、温度、pH值、氧化还原介质、7种金属离子、葡萄糖、蔗糖和苯甲酸钠等对其稳定性的影响进行了研究。结果表明,木莓鲜果中总花色苷含量高,属水溶性性花色苷类。该色素对热的耐受性较好,但耐氧化还原性和耐Vc较差;7种金属离子中Na^ 、Mg^2 、Al^3 和较高浓度Mn^2 (≥5.0mmol/L）对该色素的稳定性较好,并有不同程度的护色效果,Zn^2 对其稳定性较好,而Fe^3 和Cu^2 对共稳定性有明显的影响或破坏作用;葡萄糖、蔗糖和苯甲酸钠无不良影响。     

蜀葵天然色素及其稳定性研究

以新疆地产蜀葵（Althaea rosea L.Cavan.）花为实验材料,用50%乙醇 0.5%盐酸为浸提剂,物料配比为1：10,提取出蜀葵花紫红色素,并从光、温度、pH值,氧化剂,还原剂,蔗糖,苯甲酸钠和不同金属离子对色素稳定性的影响进行了初步研究,结果表明：该色素在pH2时耐光性较好,温度在65℃以下和pH值4以下时色素稳定性较好,色素耐氧化性和耐还原性较差;蔗糖和苯甲酸钠对色素稳定性无不良影响,金属离子Cu^2 ,Fe^3 ,Sn^2 和Pb^2 对该色素稳定性有不良影响,Zn^2 对色素的稳定性只有轻微影响,而Al^3 ,Na^ ,Mg^2 ,K^ ,Fe^2 和Ca^2 对色素的稳定性则皆无不良影响。     

一串红天然色素及其稳定性研究

以新疆地产一串红（Salvia splendens Ker-Gawl)的花为实验材料,从光、温度、pH值、还原介质、氧化介质、防腐剂、金属离子等影响因子方向对色素的稳定性进行了初步研究。结果表明：该色素属于花青苷类色素;对光、温度等比较稳定;可在偏酸或中性介质中使用;耐还原性和耐氧化性较差;蔗糖、防腐剂以及大多数金属离子对色素的稳定性无不良影响,但Fe^3 、Pb^2＋和Sn^2 对色素的稳定性有一定影响。     

榆叶梅天然色素及其稳定性研究

以新疆地产榆叶梅花为实验材料,对榆叶梅花食用色素提取时间、提取温度、物料配比进行不同组合的对比实验研究;对光、热、pH值、还原介质、氧化介质、蔗糖、防腐剂、维生素和金属离子等对色素的稳定性影响进行了研究。结果表明：榆叶梅花色一本正经不为水溶性色素属黄酮类色素。适用pH值范围较广,尤其酸性状态pH1－5最佳;蔗糖和防腐剂以及金属离子Zn^2 、Mg^2 、Ca^2 、K^ 、Na^2 对色素稳定性无不良影响;耐氧化剂与还原剂性能较差;而Fe^2 、Fe^3 、Cu^2 、Sn^2 、Pb^2 对色素稳定性有一定影响,其颜色相反发生改变。     

枣皮红色素的提取及其稳定性研究

对枣皮红色素的提取工艺及其稳定性进行了系统研究。结果表明枣皮红色素水溶性较好,色素溶液对光、热比较稳定;在酸、碱、金属离子、氧化剂、蔗糖等添加剂中具有较好的稳定性;但在含氧酸根阴离子、还原剂、Vc、苯甲酸钠、山梨酸钾等添加剂中稳定性较差。     

红龙草红色素稳定性的研究

分析了pH值、温度、光、过氰化氢、亚硫酸钠、Vc、葡萄糖、蔗糖和苯甲酸钠等对红龙草（Altemanthera dentate ‘Ruliginosa’）红色素稳定性的影响。结果表明,红龙草红色素对热的耐受性较强,但耐光照和耐氧化性较差,且还原剂亚硫酸钠对其也有微弱的影响;在不同的pH值条件下,其吸收峰没有改变,最大吸收波长为530nm;Vc和蔗糖对该色素没有破坏作用,并有一定的护色效果;葡萄糖和苯甲酸钠对该色素也无明显影响。     

红肉李色素稳定性的研究

本试验研究了红肉羊色素的稳定性。结果表明：红肉李色素耐热性很好,ｐＨ值对该色素有明显影响,宜在酸性食品中应用,金属离子Ｎａ＾＋、Ｚｎ＾２＋对该色素的色泽有增强作用、Ｆｅ＾２＋则有破坏作用。蔗糖对该色素无不良影响,而Ｖｃ则有不良影响,防腐剂苯甲酸钠亦有一定的不良影响。红肉李色素耐还原能力较强,耐氧化能力较差。     

食品添加剂和金属离子对高粱泡红色素稳定性的影响

探讨了5种常用食品添加剂和7种金属离子对高粱泡红色素稳定性的影响。结果表明:葡萄糖、蔗糖和苯甲酸钠对高粱泡红色素稳定性无不良影响,其中葡萄糖、蔗糖有不同程度的增(护)色效果;柠檬酸能显著提高色素的稳定性;而VitC能促进色素的氧化降解,有明显的破坏作用。金属离子中,Na⁺、Mg²⁺、Al³⁺、Zn²⁺等对高粱泡红色素稳定性无影响,且有一定增色作用;较高浓度(≥0.0025mol/L)Mn²⁺有一定不良影响,而Cu²⁺、Fe³⁺则有明显的破坏作用。     

榕树叶红色素的提取及其稳定性研究

为生产各种食用品、化妆品、医药药品等色素新产品提供重要原料,研究榕树叶红色素的提取条件和稳定性。以水作提取剂,在室温下浸提24h,用紫外分析法研究色素的稳定性。色素在330am有最大吸收峰,该色素水溶性较好,pH值对色素的稳定性影响较大,但热稳定性良好。苯甲酸钠、柠檬酸、醋酸、蔗糖及葡萄糖等食品添加剂对色素无明显影响,淀粉对其影响较大,耐光性较差。氧化剂、还原剂中除抗坏血酸对色素的影响明显外,其他均无明显影响,金属离子对其影响较小。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.