青藏茶藨子种子中的脂肪酸含量分析

藨用超临界萃取技术对青藏高原藏药特有植物青藏茶藨子种子中脂肪酸进行了萃取,其萃取率为12．0%。用毛细管气相色谱进行分离和分析,结果表明不饱和脂肪酸在90％以上。其中α-亚麻酸26．23％、γ-亚麻酸2．60%、亚油酸43．21％。     

糖茶藨种子脂肪酸含量分析

用超临界萃取技术对产于青藏高原上的糖茶蔗种子中脂肪酸进行萃取,其萃取率为12％。用毛细管气相色谱对萃取的脂肪酸进行了分离和分析。结果表明不饱和脂肪酸的质量分数在90％以上。其中α-亚麻酸（α-linolenic acid）为27.4％,У-亚麻酸（У-linolenic acia）为2．70％。亚油酸（1inoleic acid）40．0%,油酸（oleic acid）21．0％。     

滇池水华蓝藻中γ-亚麻酸的提取与含量分析

目的：在控制水华蓝藻的同时,有效利用滇池富营养化水体的水华蓝藻。方法：藻类资源。以从滇池中收集的水华蓝藻干粉为材料,对从水华蓝藻中γ-亚麻酸的含量进行了分析,对提取γ-亚麻酸的几个基本参数进行了研究。结果：直接用萃取溶剂浸泡藻粉,并用超声波破碎细胞,可以简化操作且增加γ-亚麻酸得率;石油醚是比较合适的萃取溶剂;进行皂化反应时所用皂化液为(KOH-CH3CH2OH-H2O)。最适反应温度为50～60℃,γ-亚麻酸酯在氮气保护下进行酸化可以防止游离出来的γ-亚麻酸被氧化。滇池水华蓝藻中γ-亚麻酸的含量达到0．8957％。     

藏药波棱瓜籽油脂中脂肪酸的HPLC与GC—MS分析

分别采用柱前衍生-高效液相色谱荧光检测法(HPLC-FLD)和气相色谱质谱法(GC-MS),分析了超临界CO2萃取得到的藏药波棱瓜籽油脂中脂肪酸的成分.用荧光衍生试剂1-[2-(对甲苯磺酸酯)乙基]-2-苯基咪唑[4,5-f]9,10-菲(TSPP)作为柱前衍生化试剂对39种饱和与不饱和脂肪酸标品进行衍生,经梯度洗脱实现了39种游离脂肪酸(FFA)衍生物完全分离,使用外标法定量,建立了同时测定39种脂肪酸绝对含量的方法,对超临界CO2萃取结合正交实验得到的波棱瓜籽油样品及超声波萃取与微波回流萃取油脂中的脂肪酸进行了定量分析,对比了这些样品中油酸、亚油酸、亚麻酸的质量百分含量及不饱和脂肪酸占总脂肪酸的含量.结果表明:波棱瓜籽油中油酸、亚油酸、亚麻酸质量百分含量分别高达34.65%(147.14 mg/g,下同)、22.85%(97.03 mg/g)、20.86%(88.56 mg/g),不饱和脂肪酸占总脂肪酸的79%.同时,采用GC-MS分析,对比了酸催化与碱催化的甲酯化法分析波棱瓜籽油中脂肪酸的优劣,得出了GC-MS分析波棱瓜籽油脂肪酸的条件,并讨论了液相色谱与气质联用分析脂肪酸的特点.     

石榴籽油的提取及成分分析

采用正交试验方法研究了超临界CO_2萃取石榴(Punica granatum L)籽油的技术体系,并用气相色谱-质谱联用仪对石榴籽油的化学成分进行了分析。结果表明,超临界CO_2萃取石榴籽油的最佳工艺条件为:萃取压力25 MPa,萃取温度30℃,分离温度55℃,萃取时间70min,在此条件下油脂产率为20.4%。GC-MS分析的结果显示,石榴籽油的主要成分是脂肪酸。饱和脂肪酸以棕榈酸为主,不饱和脂肪酸主要是亚麻酸和亚油酸,占脂肪酸总量的86.86%。     

基于文献分析的中国猕猴桃属植物亚麻酸资源研究

通过调查和文献整理,对中国猕猴桃属植物资源中含α-亚麻酸的猕猴桃种类、分布特点以及α-亚麻酸含量、提取方法进行统计分析。结果表明,我国已报道富含亚麻酸的猕猴桃属共有11个物种、10个栽培品种;富含α-亚麻酸的猕猴桃植物资源主要分布在长江流域,少量分布在东北和西南地区;猕猴桃籽油中α-亚麻酸含量总体集中在40%~70%之间,属于高含量亚麻酸资源植物;不同提取方法对猕猴桃亚麻酸的提取效果有较大影响,以尿素包合法和分子蒸馏技术分离纯化的提取效果较好,提取的α-亚麻酸含量高达87.20%。     

α-亚麻酸对干旱胁迫下水稻种子萌发的影响

亚麻酸属ω-3系统的多不饱和脂肪酸,是细胞膜的重要组成部分。在干旱胁迫下,植物通过释放α-亚麻酸重塑细胞膜的流动性,但外源添加α-亚麻酸能否提高植物对干旱的抗性尚未可知。该研究采用PEG6000模拟干旱胁迫,探讨了种子萌发过程中α-亚麻酸对水稻萌发和幼苗生长过程中抗旱性的影响。结果表明:在14%和16%PEG干旱胁迫下,水稻种子推迟萌发,幼苗的生长受到抑制。25μmol·L~(-1)和250μmol·L~(-1)的α-亚麻酸可缓解干旱对水稻幼根和幼苗生长的抑制,且随着干旱程度的增加,缓解作用增强。16%PEG胁迫下,25μmol·L~(-1)、250μmol·L~(-1)的α-亚麻酸分别提高幼苗的根长34.3%和29.1%、苗长67.8%和52.0%、根重43.9%和35.2%、苗重59.1%和43.6%。α-淀粉酶活力测定发现,25μmol·L~(-1)和250μmol·L~(-1)的α-亚麻酸分别提高干旱胁迫下水稻种子α-淀粉酶活力为56.7%~70.7%和36.8%~43.8%。水稻幼根活力测定显示,25μmol·L~(-1)和250μmol·L~(-1)的α-亚麻酸分别提高干旱胁迫下幼根活力为11.4%~28.4%和5.4%~22.2%。此外,还对不同干旱胁迫下水稻种子α-淀粉酶活性和幼根活力的变化进行了讨论,认为α-亚麻酸主要通过提高种子萌发过程中α-淀粉酶的活性来缓解所遭遇的干旱胁迫,而对水稻幼根活力的影响则相对有限。     

γ-亚麻酸高产菌株的选育及发酵产物的分离提取

以深黄被孢霉AS3.3410为出发菌株发醇产生γ-亚麻酸,其菌体得率为10%,油脂含量为27%,γ-亚麻酸含量为3.3%。经过紫外线诱变处理。得到变异株M_6,其菌体得率为25%,油脂含量为32.8%,γ-亚麻酸含量为8.84%。传代实验表明,M_6具有良好的遗传稳定性。经摇瓶发酵条件试验,选出了最佳培养基配方,以10升罐进行发酵,结果为:菌体得率29.3%,油脂含量44.7%,γ-亚麻酸含量9.44%。菌体油脂提取方法的研究表明,以乙醇和正己烷对湿菌体进行分步抽提效果较好。     

椒目中高纯度α-亚麻酸的提取分离

椒目作为一种新的木本油脂资源,其油脂中约含有30%的α-亚麻酸,采用本文创制的综合方法可对其中的α-亚麻酸进行有效分离和纯化,为椒目的综合开发和利用奠定了研究基础.椒目经皂化酸解得游离的混合脂肪酸,依次经梯度冷冻、尿素包合及硝酸银络合,得高纯度α-亚麻酸.经HPLC分析,以本文的方法得到的α-亚麻酸含量高达91.6%以上.     

影响米根霉产γ-亚麻酸的几种因素

利用气相色谱仪对根霉属的部分菌株进行脂肪酸成分分析,发现中华根霉(Rhizopus chinensis)、米根霉(Rhizopus oryzae)和匍枝根霉(Rhizopus stolonifer)均能产生γ-亚麻酸,其中米根霉R316菌丝体中γ-亚麻酸的含量较高达11.47%,对R316的液体发酵产脂条件进行研究,发现液体摇瓶培养菌丝体的油脂含量可达53.24%,γ-亚麻酸的含量提高到20.12%。R316菌丝体生长的最适碳源为葡萄糖、最适氮源为蛋白胨、最适培养温度20℃。但γ-亚麻酸积累的最适碳源为甘油、最适氮源是尿素、最适温度15℃。同时发现逆境是高产多不饱和脂肪酸的关键。     

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.