竹菌化学成分的研究

从肉座菌科真菌竹菌（Engleromyces goelzeiP.Henn)的乙酸乙酯部分分离到一个新化合物（2S,3S,4R,10E）-2-[2′R）-2′-hydroxytetracosanoyl amino]-10-octadecene-1,3,4-triol(1)和12个已知化合物,分别为cerebrosideA,cerebrosideB,cerebrosideD,cytochalasinD,expoeycytochalasinD.cytochalasin C,loganin,cerevisterol,ergosta-7,22-=dien-3β,5α,6α-triol,ergosta-4,6,8(14),22-tetraen-3-one,ergosterol peroxide和ergosta-5,7,22-trien-3-ol。利用现代波谱方法（^1H-NMR,^13C-NMR,2D-NMR和ESI-MS等）及化学方法将化合物1鉴定为一新的神经酰胺,除化合物cytochalasinD外,其余的化合物均系首次从该真菌中发现,首次从真菌界分离鉴定了一个环烯醚萜甙类化合物loganin。     

1株地衣内生真菌Preussia africana的化学成分

对分离自树花属地衣Ramalina sp.的1株内生真菌Preussia africana乙酸乙酯提取物抑制5种人参病原真菌的活性进行了初步鉴定,均具有抑真菌活性,并对其次生代谢产物的化学成分进行了分析。采用色谱分离和NMR等波谱技术对分离得到的单体化合物进行结构解析,从中得到了14个化合物,分别鉴定为zygosporin E(1)、cytochalasin C(2)、cytochalasin Q(3)、cytochalasin D(4)、1,3,6-trihydroxy-8-methyl-9H-xanthen-9-one(5)、7-hydroxy-3-(2-hydroxy-propyl)-5-methyl-isochromen-1-one(6)、2-(2′-hydroxypropyl)-5-methyl-7-hydroxychromone(7)、preussochromoneC(8)、5-methoxy-3, 5′-dimethyl-2, 3′-oxybiphenyl-1, 1′, 2′-triol(9)、3-hydroxy-5-methylphenylether(10)、(R)-7...     

木奶果茎叶的化学成分研究

采用常压柱色谱和重结晶相结合的分离方法,从木奶果的茎叶提取物的乙酸乙酯部分中分离得到8个化合物,通过波谱方法及与已知样品对照的手段鉴定它们为(2S,3S,4R)-2-[(2R)-2-hydroxytetracosanoyl-amino]-1,3,4-octadecanetriol(1),Aralia cerebroside(2),(24S)-24-ethylcholesta-3β,5α,6β-triol(3),Stigmast-4-en-6β-ol-3-one(4),7-oxo-β-sitosterol(5),7α-methoxy-sigmast-5-en-3β-ol(6),β-sitosterol(7),daucosterol(8)。化合物1-6为首次从该种植物中发现的。     

亚稀褶黑菇的化学成分

从剧毒蘑菇─亚稀褶黑菇(Russula subnigricans Hongo)子实体中分离出5个已知化合物,经波谱分析鉴定为4个麦角甾醇(22E,24R)-ergosta-7,22-diene-3β,5α,6α,9α-tetraol(1)、(22E,24R)-ergosta-7,22-dien-3β,5α,9α-trihydroxy-6-one(2)、(22E,24R)-ergosta-7,22-dien-3β,5α,6β-triol(3)、(22E,24R)-5α,8α-epidioxyergosta-6,22-dien-3β-ol(4)和神经酰胺(2S,3S,4R,2′R)-2-(2′-hydroxytetracosanoylamino)octadecane-1,3,4-triol(5)。     

滇牡丹内生真菌Alternaria sp.PR-14的代谢产物研究

从滇牡丹内生真菌交链孢霉属(Alternaria sp.)菌株PR-14的发酵液提取物中分离得到6个化合物,通过波谱技术分别鉴定为交链孢酚(1)、djalonensone(2)、脑苷酯B(3)、脑苷酯C(4)、(2S,3S,4R,2’R)-2-(2’-hydroxytetracosanoylamino)octadecane-1,3,4-triol(5)和甘露糖醇(6),以上化合物均为首次从滇牡丹内生真菌中分离得到。     

肋果茶中的萜类化学成分研究

从肋果茶(Sladenia celastrifolia)95％乙醇提取物的乙酸乙酯部位中分离得到15个萜类化合物,经波谱学方法分别鉴定为sladeniafolin A(1),grasshopper ketone (2),(3S,5R,6S,7E,9R) -7-megastigmene-3,6,9-triol (3),hedytriol (4),(3S,5R,6R,7E,9R) -3,5,6,9-tetrahydroxy-7-megastigmene(5),1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′-trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien -2-one (6),2α,3α,19α,23-tetrahydroxyurs-12-en-28-oic acid (7),2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid(8),pomolic acid(9),3-O-acetyl pomolic acid(10),ursaldehyde (11),camarolide (12),3β-hydroxyurs-11-en-13β(28) -olide (13),3β-hydroxy -11α,12α-epoxy-urs-13β,28-olide (14)和28-0-β-D-glucopyranosyl euscaphic acid (15).以上化合物均首次从该植物中分离得到,其中1为新的C9裂环烯醚萜.     

耳状网褶菌的化学成分

从野生真菌耳状网褶菌（Paxillus pamuoides Fr.)子实体中分得4个化合物,经光谱和化学方法分别鉴定为（2S,3S,4R,2′R）-2－（2′－羟基二十四碳酰氨基）十八碳－1,3,4－三醇（1）、5α,8α－表二氧－（22E,24R）－麦角甾－6,22－二烯－3β-醇[5α,8α-epidioxy-(22E,24R)-ergosta-6,22-dien-3β－o1,2]、（22E,24R）－麦角甾－4,6,8（14）,22－四烯－3－酮[(22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one,3]和对羟基苯甲酸乙酯（ethyl 4-hydroxybenzoate,4)。其中化合物4作为天然产物属首次报道。化合物1－4为本科真菌中首次分得。     

黄白红菇的化学成分

从野生真菌黄白红菇Russula ochroleuca(Pers).Fr.子实体中首次分得11个化合物,经光谱法和化学法分别鉴定为2个脑苷脂,1－0－β－D－吡喃葡萄糖基－（2S,3R,4E,8EE,2'R）－2－N－(2'－羟基棕榈酰）－9－甲基－4,8－sphingadienine(cerebrosideB,1)和1－O－β－D－啉喃葡萄糖基－（2S,3R,4E,8E,2'R) -2-N-(2'-羟基十八酰B,I）和－9－甲基－4,8－sphingadienine(cerebrosideD,2);3个麦角甾醇,5α,8α－epidioxy-(22E,24R)-ergosta-6,22-dien-3β-ol3,(22E,24R)-ergosta-7,22-dien-3β-ol4,(24S)－ergosta-7-en-3β-ol5.2个含氮杂环化合物,尿嘧啶（uracil6),腺嘌adenine7),1个含硫化合物,硫代乙酰酐（thioacetic anhydride8),以及乙基－β－D－吡喃呤（adenine7),1个含硫化合物,硫代乙酸酐（thioacetic anhydride8),以及乙基－β－D－吡喃葡萄糖苷（ethy1-β－D－glucopyranosde9),D－阿洛醇（D-allitol10),硬脂酸（stearic acid11),化合物1和2为首次从红菇科真菌获得,8作为天然产物系首次报道。     

耳状网褶菌菌丝体的化学成分研究

从耳状网褶菌 (PaxilluspanuoidesFr.)培养发酵的菌丝体中首次分出 6个化合物。通过光谱分析鉴定为 :2 1 hydroxylanosta 8,2 4 dien 3 one (1)、2 3 methylergosterolperoxide (2 )、(2S ,3S ,4R ,2′R) 2 (2′ 羟基二十四碳酰氨基 )十八碳 1,3,4 三醇 [2S ,3S ,4R ,2′R) 2 (2′ hydroxytetracosanoylamino)oc tadecane 1,3,4 triol](3)、D 赤藓醇 (D erthyritol) (4 )、对羟基苯甲酸 (p hydroxybenzoicacid) (5 )和琥珀酸(succinicacid) (6 )。化合物 1、2和 3为首次通过发酵获得     

剑叶龙血树内生真菌Colletotrichum sp.B-152次生代谢产物研究CSCD

采用色谱技术和波谱学分析从剑叶龙血树内生真菌Colletotrichum sp.B-152的培养液和菌丝中,鉴定出了9个化合物:2-hydroxy-4-methyl-1-phenyl-3-pentanone(1)、4-methyl-1-phenyl-2,3-pentanediol(2)、胸腺嘧啶核苷(3)、腺嘌呤核苷(4)、(22 E,24 R)-ergosta-7,22-diene-3β,5α,6β-triol(5)、(4 E,8 E)-N-D-2′-hydroxypalmitoyl-1-O-β-D-glycopyranosyl-9-methyl-4,8-sphingadienine(6)、tuberosider(7)、(22 E,24 R)-5α,8α-epidioxyergosta-6,22-dien-3β-ol(8)、十七烷酸(9),其中化合物1作为天然产物首次报道,化合物2~4、6、7、9首次从刺盘孢属Colletotrichum真菌中分离得到。采用滤纸片扩散法对单体化合物的抑菌活性进行测定,9个化合物对至少一种指示菌表现出不同程度的抑制作用,其中化合物7和8表现出较为广谱的抑菌活性。     

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.     

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     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.