油茶茶枯中茶皂素的提取工艺研究

油茶茶枯是南方地区一种常见的加工副产物,含有较高的茶皂素。茶皂素是工业生产中应用广泛的一种表面活性剂,性能优良,但目前茶皂素的提取工艺并不成熟。为了优化油茶茶枯中茶皂素提取的最佳工艺,提高油茶茶枯的利用率,该文以脱脂油茶茶枯粉末为原料,乙醇溶液作为浸提剂,以茶皂素的得率和含量作为提取效果的评价指标,通过单因子实验和正交试验探求油茶茶枯中茶皂素的最佳提取条件。结果表明:以提取时间、3%NaOH添加量、乙醇浓度、料液比、温度和提取次数6个因素作为单因子,对油茶茶枯中茶皂素提取得率和含量进行研究,在单因子实验的基础上进行正交试验得到茶皂素提取的最佳工艺条件为料液比1∶17,乙醇浓度75%,提取温度81℃,提取时间88min,3%NaOH添加量2.5mL(即每10g茶枯粉末中添加0.075g NaOH),提取次数2次。通过论证该结果表明,在最佳的提取条件下,提取得到茶皂素的最高含量为0.54mg·mL-1,得率为21.35%。该实验方法添加了NaOH后,在最佳条件下茶皂素的得率明显提高,对今后优化油茶茶枯中茶皂素的提取工艺具有很好的借鉴意义。     

一种提纯粗茶皂素的简易方法

对粗茶皂素的提取纯化工艺进行了研究。以质量分数为70％的粗茶皂素为原料,经2％NaOH溶解、盐酸酸析、95％乙醇溶解、丙酮沉析工艺得到精制茶皂素。检测结果表明,茶皂素质量分数大于95％,提取率大于80％,这种简便易行的工艺得到的茶皂素可作为开发新型植物灭螺剂的原料。     

油茶饼粕中茶皂素的提取及脱色研究

以油茶饼粕为原料,通过有机溶剂进行浸取,研究并确定提取了茶皂素的最佳工艺为乙醇体积分数75%,料液比(g:m l)为1:4,提取时间2 h,提取温度60℃;脱色的最佳条件为pH9,脱色温度60℃,脱色时间1 h,加入H2O220 mL。在此条件下提取的茶皂素得率为16.6%,纯化的茶皂素质量分数达到87.3%。     

鱼藤酮和茶皂素对槟榔红脉穗螟的联合毒力

【背景】鱼藤酮和茶皂素均为典型的植物源药剂,而两者混配对棕榈害虫的防治效果还未见报道。【方法】采用室内毒力测定方法研究了鱼藤酮和茶皂素以不同比例混配对槟榔红脉穗螟的联合毒力。【结果】鱼藤酮和茶皂素对红脉穗螟3龄幼虫的LC50分别为19.06和35.07 mg·L-1。鱼藤酮和茶皂素以有效成分1∶1、5∶1、1∶2和1∶5混配后,对红脉穗螟均表现出增效作用。其中以1∶5混配处理组的共毒系数最高,达327.26;1∶2混配处理组次之,共毒系数为298.16。【结论与意义】鱼藤酮和茶皂素以合理比例混配,对红脉穗螟具有增效作用。     

新型茶皂素毒鱼剂与传统茶皂素毒鱼剂对罗非鱼的毒杀效能比较

采用水箱养殖方式,通过新型茶皂素毒鱼剂与传统茶皂素毒鱼剂对罗非鱼的药效-剂量关系和毒鱼持续能力的对比。结果显示,新型茶皂素毒鱼剂对罗非鱼的6h有效致死剂量为5-6mg/L左右。6h半致死剂量LD50约为5.0mg/L,12h绝对致死剂量LD100为6.0mg/L。6h的最小致死剂量MLD为5.0mg/L,6h最大耐受剂量MTD为2.5mg/L左右。且其在毒鱼持续能力方面明显优于传统的茶皂素毒鱼剂。     

油茶籽粕中茶皂素的优化提取及抑菌活性的研究

以油茶籽粕为原料,采取超声波辅助乙醇提取法,考察了料液比、浸提时间、超声时间、乙醇体积分数对茶皂素得率的影响,并用响应面优化实验设计得出最优提取条件,优化条件为:料液比1∶7(m/V)、浸提时间93min、超声时间36 min、乙醇体积分数55%,在该条件下茶皂素得率为14.708%。依照此优化方案进行验证实验,结果显示模型可靠性较高,可以较好的预测实际情况。同时茶皂素抑菌效果表明茶皂素对金黄色葡萄球菌有较好的抑菌效果,而对大肠杆菌没有抑菌效果。     

茶皂素对菜青虫的拒食作用方式及机制

采用注射、熏蒸、点滴、饲喂、内吸等方法测定了茶皂素对菜粉蝶Ｐｉｅｒｉｓ　ｒａｐａｅ　Ｌ．５龄幼虫的拒食活性。结果表明,茶皂素对５龄菜青虫具有很强的饲喂拒食活性,２４小时选择性拒食中浓度ＡＦＣ_(５０)为４０．８８ｍｇ／Ｌ,非选择性拒食中浓度为３２１．９２ｍｇ／Ｌ;并具有一定的内吸拒食作用,尤其是根部施药法内吸拒食活性较明显。茶皂素对菜青虫无显著的注射、熏蒸、点滴拒食作用。     

茶皂素对尼索朗杀灭桔全爪螨的增效作用

本文就茶皂素对尼索朗杀灭桔全爪螨的增效作用,进行了室内及田间药效试验。     

茶皂素生产工艺及其应用的研究进展

本文综述了天然非离子表面活性剂茶皂素的生产工艺以及在实际中的应用 ,并就目前的生产和使用情况提出了一些看法和需要解决的问题。     

茶皂素光波干法提取与产品开发

本文考察茶皂素的微波光波组合无溶剂提取方法,发现微波光波提取干法不用溶剂,仅用微量的DMF作为能量传递介质,提取速度是传统提取方法的1800倍以上,成本明显降低.利用高倍FM、IR等手段对微波提取机理进行初步研究,从微波对植物组织结构的影响上阐明次生代谢产物的微波提取机理.利用提取的茶皂素开发成洗发香波,对多个配方进行了多方面的性能评价,其中两个配方的多项指标达到或优于国家标准.     

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.