苦荞粉中的化学成分

从荞麦属植物苦荞（Fagopyrum tataricum）的籽粒面粉中分离鉴定出9个化合物,其结构分别为：β-谷甾醇棕榈酸酯（1）,β-谷甾醇（2）,豆甾-4-烯-3,6-二酮（3）,胡萝卜甙（4）,尿嘧啶（5）,山萘酚-3-O-芸香糖甙（6）,芦丁（7）,山奈酚（8）和槲皮素（9）。除芦丁和槲皮素外,其余化合物均为首次从苦荞粉中分离得到。     

纸莎草的化学成分研究

采用正相硅胶柱、Sephadex LH-20、高效液相色谱、MCI等色谱方法从纸莎草全株中分离得到19个化合物,采用1D、2D NMR、质谱等技术鉴定化合物的结构,分别鉴定为:α-香附酮(1)、香附酸(2)、广藿香烯酮(3)、4,5,6,7,8,8a-六氢-3,4,8,8-四甲基-1H-3a, 7-亚甲基甘菊环-4-醇甲酸酯(4)、(6S)4-烯-广藿香醇(5)、桉烷双烯萜(6)、β-谷甾醇(7)、(24R)-24-乙基胆甾烷-4-烯-3,6-二酮(8)、豆甾-4,22-二烯-3-酮(9)、(24R)-24-乙基-5α-胆甾烷-3β,5-二醇-6-酮(10)、豆甾醇(11)、豆甾-4-烯-6β-醇-3-酮(12)、豆甾-3,6-二酮(13)、豆甾-4-烯-3-酮(14)、顺,顺-9,12-十八(碳)二烯酸(15)、棕榈酸甲酯(16)、正二十八烷酸(17)、3-壬基环氧乙烷-2-甲酸甲酯(18)、9,10-二氯-十八烷酸甲酯(19)。所有化合物均为首次从纸莎草中分离得到。化合物1、2、3、5、6、10、12、13、16能够明显抑制TNF-α所诱导的质粒转染的HEK293T细胞中NF-κB信号通路的激活,IC_(50)值在34.96～98.23μM之间。     

白木香内生真菌Botryosphae riarhodina A13固体发酵产物的分离鉴定北大核心CSCD

运用硅胶柱、反相硅胶柱、凝胶柱、HPLC和薄层制备等色谱技术及重结晶从白木香内生真菌Botryosphaeria rhodina A13的固体发酵产物中分离纯化了10个化学成分,通过化合物波谱数据及理化性质鉴定它们的结构分别为豆甾-4-烯-3-酮（1）、豆甾-5-烯-3β-醇-7-酮（2）、豆甾-4-烯-3,6-二酮（3）、（22E,24S）-5α,6α-环氧基-24-甲基胆甾-8（14）,22-二烯-3β,7α-二醇（4）、5,4＇-二羟-7-甲氧基黄酮（5）、香草酸（6）、对甲氧基苯甲酸（7）、尿嘧啶（8）、2-甲氧基对苯二酚（9）、2-甲基-3,5-羟基色酮（10）。其中化合物1～10均为首次从该属真菌中分离得到,化合物4具有细胞毒活性。     

羊角天麻化学成分及β-羟高铁血红素形成抑制活性研究

为探究羊角天麻(Dobinea delavayi)的β-羟高铁血红素形成抑制活性成分,本实验采用硅胶、Sephadex LH-20柱色谱等方法进行化合物的纯化分离,通过理化性质及波谱数据鉴定化合物结构。结果从羊角天麻中分离得到12个化合物,分别鉴定为3,4,2′,4′-四羟基二氢查尔酮(1)、紫铆花素(2)、3,4,2′,4′,α-五羟基查尔酮(3)、金色草素(4)、芒果苷(5)、没食子酸(6)、二十四亚甲基环阿尔廷醇(7)、6β-羟基-豆甾-4-烯-3-酮(8)、β-谷甾醇(9)、胡萝卜苷(10)、棕榈酸甲酯(11)、1-棕榈酸单甘油酯(12),其中化合物1~4、6~8均为首次九子母属植物中分离得到。活性研究结果显示,化合物1~6均具有β-羟高铁血红素形成抑制活性,其中黄酮类化合物2~4具有较强的抑制活性,其IC50分别为120.3、61.5、56.0μg/mL。     

罗汉松内生真菌Pestalotiopsis heterocornis的代谢产物研究

从罗汉松内生真菌Pestalotiopsis heterocornis的发酵培养液中分离得到10个代谢产物,应用质谱、核磁共振等现代波谱学方法鉴定为jesterone(1),hydroxy-jesterone(2),ambuic acid(3),6β-羟基-豆甾-4-烯-3-酮(4),(24S)-麦角甾-5-烯-3β,7α-二醇(5),7,22-二烯-3β,5α,7β-三羟基-麦角甾醇(6),麦角甾-7,22-二烯-3-酮(7),(4E,8E,2S,3R,2'R)-N-2'-羟基棕榈酰-9-甲基-4,8-sphingadienin(8),鲨肝醇(9),棕榈酸(10)。以上化合物均为首次从内生真菌P. heterocornis的代谢产物中分离得到,化合物4,6,7为首次从拟盘多毛孢属真菌代谢产物中分离得到。     

清香木姜子的化学成分

从清香木姜子（Litsea euosma W．W．Smith）的枝叶中分离得到1个新化合物-α-吡喃酮衍生物（1）以及3个已知化合物：阿魏酸酯衍生物（2）,6-氧-棕榈酰-β-胡萝卜甙（3）和葡萄糖（4）,经波谱学鉴定新化合物α-吡喃酮衍生物的结构为：5-经基-6-甲基-3-（10-十一烯基）-5,6-二氢吡哺-2-酮。     

红背山麻杆根中PTP1B抑制活性成分研究

运用硅胶和凝胶色谱等天然产物分离技术从红背山麻杆根中分离得到9个化合物,结合各化合物理化性质和光谱数据鉴定其结构,包括6个三萜类成分鲨烯(1)、乙酰基木油醇酸(2)、木栓酮(3)、3-乙酰氧基-12-齐墩果烯-28-酸甲酯(4)、马斯里酸(5)、马斯里酸甲酯(6)和3个甾醇成分β-谷甾醇(7)、β-谷甾醇-3-O-硬脂酸酯(8)、豆甾-4-烯-3,6-二酮(9)。化合物2、3和7为首次从该植物中分离得到,其余化合物均为首次从该属植物中分离得到。以体外酶学方法测定化合物PTP1B抑制活性,化合物2、5、6和8具有PTP1B抑制活性。     

草鞋木的化学成分研究

采用硅胶、Sephades LH-20、RP-18等色谱技术,对草鞋木(Macaranga henryi)枝条中的化学成分进行了研究,共分离得到8个化合物,通过NMR、MS等波谱学技术将其结构分别鉴定为:12-O-tetradecanoylphorbol-13-acetate(1),trigowiin A(2),daturadiol(3),山楂酸甲酯(4),3β-羟基豆甾-5-烯-7-酮(5),3β-羟基豆甾-5,22-二烯-7-酮(6),豆甾-3,5-二烯-7-酮(7),丁香脂素(8)。化合物5为首次从该种植物中分离得到,其余化合物均为首次从该属植物中分离得到。     

空心莲子草的化学成分研究

用硅胶柱层析和凝胶柱层析对药用植物空心莲子草Alternanthera philoxeroides (Mart.)Griseb全草的石油醚提取物进行分离纯化,从中分离得到7个化合物,通过波谱学数据和已知化合物数据作比较,分别鉴定为2-羟基-3-甲基-蒽醌(2-hydroxy-3-methyl-anthraquinone,1),2-羟基-1-甲氧基-蒽醌(2-hydroxy-1-methoxyl-anthraquinone,2),二十四烷酸α-单甘油酯(tetracosanoic acid 2,3-dihydroxypropyl ester,3),二十六烷酸α-单甘油酯(hexacosanoic acid 2,3-dihydroxypropyl ester,4),十八烷酸α-单甘油酯(monostearin,5),△5,22-豆甾烯醇-3-O-β-D-葡萄糖苷-6′-棕榈酸酯(△5, 22-stigmast-3-O-β-D-glucopyranosyl-6′-hexadecanoate,6),豆甾醇-3-O-β-D-吡喃葡萄糖苷(stigmasterol-3-O-β-D-glucopyranoside,7).化合物1和2为首次从该植物中分离得到,3～6均首次从该属植物中分离得到.     

维药瘤果黑种草籽化学成分研究

为研究维药瘤果黑种草籽的化学成分,采用硅胶、ODS柱色谱等方法分离纯化,分离并鉴定了16个化合物,利用理化性质及波谱方法鉴定化学成分的结构分别为:Nigeglanine(1)、附子碱(2)、L-色氨酸(3)、L-色氨酸甲酯(4)、5,7-二羟基-异苯并呋喃酮(5)、豆甾醇(6)、豆甾醇-3-O-β-D-葡萄糖苷(7)、β-谷甾醇(8)、β-胡萝卜苷(9)、亚油酸(10)、邻苯二甲酸二丁酯(11)、棕榈酸(12)、十六烷酸1-甘油酯(13)、硬酯酸(14)、硬酯酸2-甘油酯(15)和蔗糖(16)。其中化合物3～5、7、9、11和15为首次从该种药材中得到。     

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.