金蝉花核苷类成分的LC-MS定性分析与HPLC含量测定

本文采用高效液相色谱-质谱联用法定性分析金蝉花中核苷类成分,并建立了高效液相色谱法同时测定6种核苷类成分含量的方法。结果定性分析出金蝉花中13种核苷类成分,腺嘌呤、尿苷、肌苷、鸟苷、腺苷和N6-(2-羟乙基)腺苷在2.34～18.67、4.77～38.13、3.48～27.87、1.13～9.07、4.76～38.04、2.84～22.76μg/mL范围内呈良好的线性关系(r0.999 1),平均加样回收率为97.32%～102.37%,且精密度、重复性、稳定性良好,可用于金蝉花中主要核苷类成分的同时测定;不同产地的金蝉花中核苷类成分含量存在差异,安徽大别山和江苏句容的6种核苷类总量相对较高,浙江天目山、安徽宣城和福建三明相对较低;不同部位的金蝉花样品中,腺嘌呤、尿苷、肌苷、鸟苷、腺苷在子实体中含量均高于菌核,而N6-(2-羟乙基)腺苷则在菌核中含量较高。以上结果可为金蝉花的质量控制及深入开发利用提供参考。     

灵芝孢子粉中核苷类成分分析

本文利用高效液相色谱方法（HPLC）同时对灵芝孢子粉中的15种核苷类成分的含量进行测定。采用Ultimate AQ-C₁₈（4.6mm×250mm,5μm）色谱柱,以甲醇和水为流动相进行梯度洗脱,流速1.0mL/min,检测波长259nm,柱温30℃,进样量10μL。方法学考察结果表明,该方法准确度高,稳定性、精密度、重现性好,适用于灵芝孢子粉中核苷类成分的测定分析。运用建立的方法对不同破壁时间、不同采收时期龙泉、奉化、大别山、黄山4个产区的灵芝孢子粉中的15种核苷类成分的含量进行测定。结果表明破壁处理对灵芝孢子粉中核苷类成分提取率的影响不大,不同产地的灵芝孢子粉中核苷类成分的组成和含量具有显著差异,且孢子粉中的核苷含量随着产粉时间的延长有所增加。各待测样品中均含有胞嘧啶、尿苷、腺嘌呤、鸟苷、腺苷等成分,其中尿苷、鸟苷、腺苷3种核苷的含量占总量的比例在待测样品中均达到70%以上,为灵芝孢子粉中的主要核苷类成分。     

不同采收期玄参中核苷类成分的含量分析

建立UPLC-QTRAP-MS/MS同时测定玄参中10种核苷类成分含量的方法,分析不同采收期玄参中核苷类成分动态积累变化。采用UPLC-QTRAP-MS/MS技术同时测定玄参样品中10种核苷类成分的含量。玄参核苷类成分中,以鸟苷、尿苷、腺苷、尿嘧啶含量较高;不同采收期玄参核苷类成分含量有所差异,11月份核苷含量相对较高。为探究玄参药材的品质形成机制及确定药材适宜采收期提供基础资料。     

高效液相色谱法测定三种虫草发酵液与菌丝体核苷化合物含量

本项研究测定了三种虫草(江西虫草、古尼虫草、戴氏虫草)发酵液与菌丝体中核苷类化合物的含量,并建立了定量分析的方法体系。其中,采用液体发酵的方法获得虫草菌丝体及其发酵液,应用超声破碎法提取虫草菌丝体中的核苷类化合物,最后应用高效液相色谱法-二极管阵列检测器进行色谱分析,并以保留时间和吸收光谱双指标作为定性依据。实验取得了预期结果:优化了5种核苷化合物:腺苷、虫草素、尿苷、肌苷、鸟苷的色谱分离条件,分析了3种虫草中核苷类化合物的含量,精密度、稳定性、重现性和回收率实验表明这一方法可高效地定量分析虫草中的核苷类化合物。实验表明,HPLC-DAD法对虫草中的核苷类化合物的定量分析是一种有效的方法,该方法可快速准确地检测虫草有效成分的含量,本研究同时测定了胞外部分的化合物含量,系首次对这三种虫草细胞内外成分同时进行测定,对虫草的品质评价体系及其质量控制标准的建立具有重要意义。     

HPLC法同时测定延胡索不同部位中11种核苷类成分

目的：测定并评价不同产地延胡索药材不同部位中11种核苷类成分的含量。方法：采用高效液相色谱法测定核苷类成分的含量，并对测定结果进行聚类分析。结果：不同产地延胡索中核苷类物质含量由高到低为鸟苷>尿苷>腺苷>肌苷>胞苷>尿嘧啶>2’-脱氧肌苷>2’-脱氧胸苷>腺嘌呤>胸腺嘧啶>2’-脱氧腺苷，11种核苷总含量整体表现为叶>茎>块茎，不同产地延胡索核苷类总含量由高到低为浙江磐安>浙江东阳>陕西汉中>重庆万州>重庆开州，块茎中的11种核苷成分含量比无显著性差异，但茎和叶差异较大。结论：此方法可用于延胡索不同部位中核苷类成分的测定，为其综合利用提供思路。     

古尼虫草核苷类成分的高效液相色谱分析

以已知核苷为标样,并以冬虫夏草做对比,利用反相高效液相色谱法对古尼虫草及其发酵菌丝体的核苷类化学成分进行了分析,结果表明古尼虫草和冬虫夏草主要含有7种标样核苷中的腺苷、胞苷、尿苷,其含量相当,而古尼虫草发酵菌丝体中腺苷和尿苷的含量是古尼虫草子座或僵虫体的2～3倍。     

古尼虫草核苷类成分的高效液相色谱分析*

以已知核苷为标样,并以冬虫夏草做对比,利用反相高效液相色谱法对古尼虫草及其发酵菌丝体的核苷类化学成分进行了分析,结果表明古尼虫草和冬虫夏草主要含有7种标样核苷中的腺苷、胞苷、尿苷,其含量相当,而古尼虫草发酵菌丝体中腺苷和尿苷的含量是古尼虫草子座或僵虫体的2~3倍。     

食用菌菌丝体中糖醇类成分含量测定的研究

采用高效阴离子色谱-脉冲安培法(HAPEC-PAD)对食用菌菌丝体中糖醇类成分赤藓糖醇、阿糖醇和甘露醇进行分析,并对赤藓糖醇测定的方法进行考察,结果表明该方法对赤藓糖醇的分析具有灵敏度高、分离度好、检测效率高等特点。不同食用菌菌丝体均含有糖醇类成分,但含量和种类差异大,同时发现百令胶囊的测定结果与药典有较大差异,主要含有赤藓糖醇,而非甘露醇。此研究为糖醇类成分的质量标准的建立奠定了基础。     

不同产地冬虫夏草的质量参数测定

冬虫夏草Ophiocordyceps sinensis是传统的名贵中药,其不同产地的质量评价存在争议。本文对从青海、四川、西藏和云南采集的冬虫夏草进行形态和分子鉴别,测定腺苷、肌苷、麦角甾醇、虫草酸和多糖的含量,检测甲醇提取物抗DPPH自由基和抗小鼠乳腺癌细胞MT-1的活性。结果表明,采集的样品均为冬虫夏草;在四种样品中,虫草酸和多糖的含量高于腺苷、肌苷和麦角甾醇的含量;采自云南和青海冬虫夏草的五种活性成分含量均高于西藏和四川冬虫夏草的含量;云南和西藏的冬虫夏草清除DPPH自由基活性高于青海和四川的冬虫夏草;不同产地的冬虫夏草抑制MT-1活性没有显著性差异。结果为综合科学评价冬虫夏草质量提供参考。     

中国被毛孢发酵液的活性成分分析及清除自由基和抗白色假丝酵母活性的研究

测定处于不同生长期的中国被毛孢Hirsutella sinensis菌株RCEF0273胞外多糖含量、发酵液中5种核苷代谢量和氨基酸含量,并对其菌株次生代谢产物清除自由基活性和抑菌效果进行了测定分析,发现:中国被毛孢胞外多糖含量最高可达到1.9480g/L,发酵液中尿苷、鸟苷、肌苷、胸腺嘧啶核苷和腺苷5种核苷含量最高分别为10.4132mg/g、12.1929mg/g、2.2698mg/g、1.1000mg/g和1.8181mg/g,其菌株发酵液冻干粉中氨基酸总量为3.2560mg/g,活性测定结果显示中国被毛孢发酵液的正丁醇相有很强的清除自由基活性和抑菌活性。在10mg/mL的测试浓度下,37℃孵育15min后其自由基清除率可达93.25%,在2mg/mL的测试浓度下,其抗白色假丝酵母Candida albicans的抑菌圈直径达到21.42mm。     

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.     

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.     

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