银木叶精油化学成分的研究

用毛细管气相色谱-质谱-计算机联用技术、毛细管气相色谱保留指数法和标准品叠加法分析了银木叶精油的化学成分。从分离出来的250个成分中,初步鉴定出59个成分,其含量占总组成的97.27％。最主要成分是樟脑(28.57％)等。     

夜合花叶的精油成份研究

利用气相色谱—质谱—计算机联用技术对夜合花[Magnolia coco(Lour.)DC.]叶的精油成份进行了分析。从分离出的139个色谱峰中鉴定出25个化合物,其含量占总组成的66.358％,主要成份是β-松油烯(37.570％),松油醇4(6.504％),α-蒎烯(3.499％),去氢白菖蒲烯(2.758％),芳樟醇(2.440％),1-(1,5-二甲基-4-己烯)苯(2.436％)等。     

超临界CO2提取栀子花头香精油组成研究

本文报道了用毛细血管气相色谱、色谱-质谱计算机联用技术以及薄层色谱等方法分析了采用超临界 CO_2提取的栀子花头香精油化学成分。从分离出来的58个峰中初步鉴定出24个组分,占色谱峰总面积的93％。其中主要成分是顺-3-已烯醇(1.68),惕各酸甲酯(3.92％),苯甲酸甲酯(37.34％),芳樟醇(20.54％),香苇醇(10.33％),惕各酸顺-3-已烯酯(20.30％)等。     

GC-MS分析伊犁绢蒿挥发油化学成分

利用水蒸气蒸馏法提取伊犁绢蒿挥发油,出油率为0．25％。采用色谱-质谱-计算机联用技术,从检出的30个成分中鉴定出28个,所鉴定成分占挥发油色谱总峰面积的98．66％。其主要化学成分为α-苎酮(78．74％)、樟脑(6．17％)、桧烯醇乙酸酯(1．94％)、β-苎酮(1．40％)、乙酸乙酯(1．14％)等,占总挥发油成分的89．46％。     

国产松露乙醚提取物的GC-MS分析

采用气相色谱-质谱(GC-MS)法分析我国云南产黑松露(Tuber indicum)乙醚提取物的化学成分.从中鉴定了56个化合物,占提取物总含量的87.37％,化合物组成特征:以脂肪酸类化合物为主,占59.98％,其中含亚油酸达26.51％;醇、酯、醛和烃类化合物分别占7.96％、2.79％、2.44％和13.12％,另外还含有少量的苯衍生物,占1.08％.     

四川米易逸生植物毛叶丁香罗勒精油化学成分研究

用气相色谱保留指数定性法,气相色谱-质谱-计算机联用技术和标准品叠加法研究了米易县的逸生植物——毛叶丁香罗勒(Ocimum gratissimum L.var.suvae Willd)的精油化学成分。从分离出的53个色谱峰鉴定出21个化合物.主要成分是丁香酚(84.500％)、顺-罗勒烯(4.567％)、顺-石竹烯(1.516％),α-依兰油烯(2.457％)。已鉴定成分相对含量占全油的96.641％.此精油的丁香酚含量明显高于其它地区栽培的同种植物.     

木姜子叶精油的化学成分研究

采用气相色谱-质谱联用仪对产于秦岭太白山的木姜子叶的挥发油成分进行分析鉴定,从分离出的79个峰中鉴定了32种成分,其含量占挥发油总量的90.59％,主要成分为1,3,3-三甲基-乙-氧杂双环[2,2,2]辛烷(59.96％),1,8-桉油醇(8.96％),香茅醛(6.86％),2-甲基-5-(1-甲基乙烯基)环己酮(4.34％)和澄花醇乙酯(3.19％)。     

广西小叶红叶藤挥发油化学成分及抗氧化性研究

采用气相色谱-质谱联用技术对小叶红叶藤挥发油的化学成分进行分析,并用DPPH·法、ABTS,+法和铁氰化钾还原法对其抗氧化能力进行研究.结果表明:从小叶红叶藤挥发油分离出221个色谱峰,共鉴定64个化合物,占挥发油总量的95.72％,主要成分为dl-薄荷酮(53.43％)、(E)-薄荷酮(14.20％)、5-甲基-2-...     

粘叶莸精油化学成分的研究

用气相色谱保留指数定性法,色谱-质谱-计算机联用实验和标准品迭加法分析了粘叶莸 (Caryopteris glutinosa) 精油的化学成分,从分离出的76个色谱峰中鉴定出30个化合物,并测定了它们的相对含量,其主要成分为β-蒎烯(52.630％)、柠檬烯(15.030％、α-蒎烯(13.810％),香叶烯(2.890％)、红没药烯(2.419％)、α- 烯 (1.074％) 和香桧烯 (1.010％)。     

大果木姜子精油化学成分的研究

用毛细管色谱-质谱-计算机联用,毛细管色谱-红外光谱-计算机联用,毛细管色谱保留指数和标准品叠加法,分析了大果木姜子(Cinnamomum migao H.W.Li)果实精油的化学成分。从分离出的63个峰中鉴定出47个成分,其中主要成分是1,8-桉叶素(23.75％),香桧烯(10.63％),柠檬烯(8.77％)和α-松油醇(6.36％)等。     

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.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

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.