翼蓼和中华抱茎蓼挥发油化学成分分析

采用水蒸气蒸馏法分别从翼蓼和中华抱茎蓼中提取其挥发油,并用气相色谱-质谱联用技术(GC-MS)对挥发油中的化学成分进行分离和结构鉴定,运用气相色谱峰面积归一化法确定各成分的相对百分含量.结果表明:翼蓼中总共鉴定出31种成分,中华抱茎蓼中鉴定出21种成分,分别占到挥发油总含量的84.0%和93.8%,翼蓼挥发油中主要成分是表蓝桉醇(15.9%)、甲苯(8.6%)、反式橙花叔醇(6.9%);中华抱茎蓼挥发油主要成分为邻苯二甲酸二异丁酯(19.9%)、2,4-戊二酮(17.2%)、邻苯二甲酸二丁酯(11.7%)、3-甲基-2,3-二氢苯并呋喃(10.7%).     

野生蜂窝草籽中挥发油的研究

采用水蒸气蒸馏法从野生蜂窝草籽中提取挥发油,利用气相色谱-质谱联用技术对其挥发油中的化学组分进行分离和结构鉴定,运用气相色谱面积归一化法确定各个组分的相对百分含量。从蜂窝草籽挥发油中鉴出56种成分,主要组分是油酸(12.57%),棕榈酸(10.36%),1-辛烯-3-醇(7.96%),石竹烯(5.98%),2,4,6-三甲基-1,3,6-庚三烯(5.63%)等。对蜂窝草籽挥发油进行了抗氧化实验和抗菌实验,结果表明蜂窝草籽挥发油对.OH有明显的清除作用,蜂窝草籽挥发油对实验菌株均有明显的抑制和灭活作用特别是对大肠杆菌ATCC25922株和肠炎沙门菌50040株的抗菌活性表现得更为显著。     

GC-MS法分析曼陀罗挥发油的化学成分

用水蒸气蒸馏法从曼陀罗中提取挥发油,并用气相色谱/质谱联用技术(GC-MS)对挥发油的化学成分进行分离鉴定,用气相色谱峰面积归一化法确定各组分的相对含量.结果从曼陀罗挥发油中鉴定出58种化合物,占总挥发油量的92.37%.其中主要成分为5,6-二氢-6-戊基-2H-吡喃-2-酮(44.29%)、二苯胺(12.50%)、四十四烷(10.41%)、二十烷(4.19%)、(E)-3-己烯-1-醇(2.38%)、3,7,11,15-四甲基-2-十六碳烯-1-醇(2.28%)等.     

野生荆条籽中挥发油成分的研究

用水蒸气蒸馏法从荆条中提取挥发油,用气相色谱-质谱联用技术对挥发油成分进行分离和结构鉴定。从荆条籽的挥发油中鉴定出了51个组分,用气相色谱面积归一法确定了各个组分的相对百分含量,其挥发油的主要组成是β-榄香烯(27.98%),芳樟醇(12.39%),贝壳杉烯(12.00%),δ-榄香烯(10.54%),乙酯异冰片脂(8.98%)等。     

利用GC-MS技术分析油橄榄叶挥发油化学成分

本文采用同时蒸馏萃取法(SDE)提取油橄榄叶挥发油化学成分,利用气相色谱-质谱(GC-MS)联用方法分析并用峰面积归一化法得出各化学成分在挥发油中的百分含量。结果从油橄榄叶挥发油中分离出62各色谱峰,鉴定出56个化合物,占挥发性组分总量的95.6%。其中主要成分为α-芹子烯(13.13%)、β-芹子烯(10.15%)、β-石竹烯(14.29%)、橙花叔醇(6.72%)、α-石竹烯(6.60%)、3-己烯-1-醇(5.03%)、苯乙醛(5.61%)等。     

头花蓼挥发性成分研究

目的:研究头花蓼(Herba Polygoni Capitati)挥发性成分.方法:利用水蒸汽蒸馏法提取头花蓼挥发性成分,用GC/MS进行分离测定,结合计算机检索技术对分离的化合物进行结构鉴定,应用色谱峰面积归一化法计算各成分的相对百分含量.结果:分离出88个成分,确定了51个化合物,占挥发油总量的73.10%.结论:头花蓼挥发油成分大于2%的为1-辛烯-3-醇15.205%,2-己烯醛4.444%,γ-古芸烯4.220%,2-庚烯醛4.047%,壬醛3.280%,长叶冰片2.722%,蓝桉醇2.544%.含量最高的化合物为1-辛烯-3-醇.     

鸡骨柴不同器官挥发油成分分析

采用共水蒸馏法分别提取唇形科香薷属鸡骨柴茎、叶、花中的挥发油,用气相色谱-质谱联用(GC-MS)技术并结合Kovats保留指数(KI)对比法对挥发油进行了化学成分对比鉴定,运用面积归一化法确定各组分相对含量。分别从茎、叶、花中鉴定出24、33、42种成分。其中花和叶中的主要成分和相对含量相似,分别为1,8-桉树脑(21.9%,24.73%)、丁香烯(8.79%,8.51%)、γ-松油烯(4.57%,5.11%)、邻伞花烃(3.98%,6.13%)等,其次要成分差异较大。茎中的成分与花和叶中的相差较大,主要成分为棕榈酸(65.05%)、植醇(2.75%)、丁香烯(2.53%)等。结果表明,鸡骨柴茎、叶、花挥发油的成分和相对含量各不相同,均含有大量的活性成分,具有较高的应用潜力和综合开发前景。     

山莓叶挥发油化学成分的分析

本研究以水蒸气蒸馏法提取山莓叶挥发油,气相色谱-质谱法(GC-MS)鉴定挥发油的成分,峰面积归一化法确定各成分的相对含量,结果表明:山莓叶挥发油含化学成分133种,其中88种成分得以鉴定;在挥发油成分中,二十一烷(C21H44)相对含量最多,为15.7%,其次为植物醇(C20H40O)和(+)-香橙烯(C15H24),相对含量依次为12.3%,7.98%。     

花椒挥发油的化学成分分析及体外抑菌活性研究

目的:明确花椒挥发油的主要化学成分及对部分细菌、真菌的体外抑菌活性.方法:①采用水蒸气蒸馏法提取花椒中挥发油并进行GC/MS分析;②K-B纸片扩散法和浓度稀释法测试6种菌株(金黄色葡萄球菌ATCC25923、大肠埃希菌ATCC25922、铜绿假单胞菌ATCC27853、枯草杆菌ATCC6633、白色假丝酵母菌ATCC90028、近平滑假丝酵母菌ATCC22019)体外抑菌活性.结果:①GC/Ms法分离出80余个峰,鉴定出81种物质,用面积归一法确定其相对百分含量;其中5种化合物已占到总量的60%以上,分别为桉树脑15.64%、4-萜品醇15.60%、D-柠檬油精13.72%、β-月桂烯10.20%、α-蒎烯4.03%.②花椒挥发油除对铜绿假单胞菌抑菌活性不明显外,对其它5种菌株均有较好的抑菌活性.结论:①花椒挥发油中化学成分复杂,其中含量超过5%的成分仅4种且最高含量小于16%.②花椒挥发油具有明显体外抑菌活性.     

扁桃叶挥发油化学成分的研究

采用水蒸气蒸馏法提取,运用气相色谱-质谱联用技术(GC-MS),首次对扁桃叶挥发油的化学成分进行分析,并用气相色谱面积归一化法测定各成分的相对百分含量.共鉴定出其中的38种化合物,占挥发油总量的94.52%,其主要成分为:大根香叶烯(18.33%),喇叭醇(9.46%),石竹烯(9.04%),δ-杜松烯(5.73%),...     

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.     

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     

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.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various