Standardisierung der dünnschichtchromatographischen Trennungen von Flechtensäuren zur Chemotaxonomie von Flechten

Zusammenfassung Die dünnschichtchromatographische Trennung von Flechtenextrakten zur Unterstützung der Taxonomie wurde in Bezug auf die Trennleistung und auf die Reproduzierbarkeit optimiert. Dabei wurden besonders gute Trennleistungen erhalten mit dem Flie?mittelgemisch Benzol:Dioxa:Eisessig=90∶25∶4 bei Verwendung von Kieselgel, dessen Aktivit?t durch eine Umgebung mit relativer Feuchte von 70% festgelegt wurde, und mit Methylenchlorid als Eluiermittel bei Verwendung von mit Oxals?ure impr?gniertem Kieselgel und antiparallelem Aktivit?tsgradienten. Eine hohe Reproduzierbarkeit der Trennungen wurde erreicht durch Verwendung der Vario-KS-Kammer nach Geiss, die die Einstellung einer definierten Schichtaktivit?t bzw. eines definierten Aktivit?tsgradienten und eine reproduzierbare Vorbedampfung der Schicht mit Flie?mittel erm?glicht. Es konnte gezeigt werden, da? durch unterschiedliche chromatographische Trennungen der gleichen Extrakte und durch die Verwendung verschiedener Anf?rbereagenzien die Identifizierung und damit die Aussagekraft für taxonomische Probleme steigt.

---

Standardisation of the thin-layer chromatographic separation of lichen acids for the chemotaxonomy of lichens

Summary The thin-layer chromatography of lichen extracts for taxonomic studies has been optimized in relation to separation and to reproducibility. Especially good separations were found with benzene:dioxane:acetic acid (90∶25∶4) developer and silica gel thin-layer plates, whose activity was fixed by an ambient moisture content of 70%, and with methylene chloride developer and silica gel plates impregnated with oxalic acid and antiparallel activity gradient. High reproducibility of separation was obtained using the Geiss Vario-KS tank, which allows the activity of the plates or the activity gradient to be adjusted and which also allows reproducible exposure of plates to the vapour of developing solvents. By different chromatographic separations of the same extracts and by using different colour reactions the accuracy of identification for taxonomic studies has been improved.

     

Three antibacterial naphthoquinone analogues from cultured mycobiont of lichen Astrothelium sp.

<正>A new naphthoquinone compound named 7-hydroxyl-8-methoxyltrypethelone 3 together with two known compounds trypethelone 1 and trypethelone methyl ether 2 was isolated from cultured mycobiont of Astrothelium sp.The structures were elucidated by 1D and 2D NMR spectroscopic analysis as well as comparison with those reported in literatures.Compound 1 displayed significant antibacterial activity against Bacillus subtilis(ATCC 6633),and showed modest antibacterial activity against Staphylococcus aureus col(MRSA)(CGMCC 1.2465),while compounds 2 and 3 showed modest antibacterial activity against Enterococcus faecalis 850E(CGMCC 1.2135) and S.aureus col(MRSA)(CGMCC 1.2465).     

地衣协同进化研究进展

对地衣的协同进化研究现状和发展方向进行了较全面的综述,资料表明,地衣的起源可追溯到前寒武纪;在漫长的进化过程中,共生菌与共生藻之间的相互作用使地衣产生了一些特有的性状,诸如对共生菌,共生藻的生存均有利的形态结构,合成了某些地衣所特有的镒生代谢产物,地衣体内不同部位ＤＮＡ甲基化程度不同等。共生菌、藻的分离培养发现,分离培养状态下的真菌与藻类与共生状态下的在形态、生理和遗传上有较大的差异,地衣的人工重建表明,真菌与藻类在协同进化的过程中已产生了较高的专一性。     

Design,modification, and bio-evaluation of salazinic acid derivatives

Data on synthesized derivatives of salazinic acid are scarce, with existing reports addressing only derivative hexaacetyl salazinic acid. This study investigated a set of novel potential antidiabetic agents. Analogs of salazinic acid were designed and synthesized using bromination, nucleophilic addition, Friedel-Crafts alkylation, and esterification. Ten synthetic compounds were prepared and structurally elucidated, including eight new compounds (1a-1c, 2a, 3a, 3b, 4a, 4b) and two known analogs. Under bromination, salazinic acid (1) enabled the following reaction chain: oxidation, decarboxylation, and substitution. This yielded products 1a-1c, which were found to have unprecedented scaffolds. Parmosidone F (5) was prepared from 1 with orsellinic acid via Friedel-Crafts alkylation, confirming a previously reported biosynthesis route. These analogs were evaluated for enzyme inhibition of α-glucosidase, and all showed more potent activity than that of acarbose, a positive control (IC₅₀ 332 μM), with IC₅₀ values in the range 9.32–39.96 μM. An in silico molecular docking model confirmed that, in terms of enzyme inhibition, the compounds ranked as follows: 3b > 4b > 4a > 1c > 2a > 1b > 1a > 3a. The kinetics of enzyme inhibition showed 4a and 5 to be a non-competitive-type and mixed-type inhibitors, respectively.     

口腔扁平苔藓中Caspase-3和PTEN 蛋白的免疫组织化学观察

目的：探讨Caspase-3和FIEN蛋白在口腔扁平苔藓病变发生发展中的作用及两者间的关系。方法：采用S—P免疫组化方法对28例口腔扁平苔藓及5例正常口腔黏膜中Caspase-3和PTEN蛋白表达进行检测。结果：口腔扁平苔藓病损中Caspase-3的阳性率上皮层和固有层均为100％，与正常口腔黏膜相比，表达有显著统计学意义（P〈0．01）。口腔扁平苔藓病损中PTEN蛋白阳性率为100％，与正常口腔黏膜相比，无统计学差异（P〉0．05）。口腔扁平苔藓中Caspase-3与PTEN蛋白表达呈正相关，（P〈0．05）。结论：Caspase-3和PTEN蛋白均参与口腔扁平苔藓病变的发生及发展过程，且两者之间具有相关性。     

局部激素制剂涂布治疗糜烂型扁平苔藓的疗效观察

探讨地塞米松制剂局部涂布治疗糜烂型扁平苔藓的疗效。将46例患者随机分为治疗组和对照组,每组23例。治疗组用地塞米松制剂局部涂布,连用3周;对照组给予地塞米松口服,3周为一疗程。结果表明:治疗组疗效优于对照组。说明地塞米松制剂局部涂布能有效治疗糜烂型扁平苔藓,延长复发期。     

A rapid and reliable method for Pb isotopic analysis of peat and lichens by laser ablation-quadrupole-inductively coupled plasma-mass spectrometry for biomonitoring and sample screening

An analytical protocol for rapid and reliable laser ablation-quadrupole (LA-Q)- and multi-collector (MC-) inductively coupled plasma-mass spectrometry (ICP-MS) analysis of Pb isotope ratios (²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb) in peats and lichens is developed. This technique is applicable to source tracing atmospheric Pb deposition in biomonitoring studies and sample screening. Reference materials and environmental samples were dry ashed and pressed into pellets for introduction by laser ablation. No binder was used to reduce contamination. LA-MC-ICP-MS internal and external precisions were <1.1% and <0.3%, respectively, on both ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb ratios. LA-Q-ICP-MS internal precisions on ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb ratios were lower with values for the different sample sets <14.3% while external precisions were <2.9%. The level of external precision acquired in this study is high enough to distinguish between most modern Pb sources. LA-MC-ICP-MS measurements differed from thermal ionisation mass spectrometry (TIMS) values by 1% or less while the accuracy obtained using LA-Q-ICP-MS compared to solution MC-ICP-MS was 3.1% or better using a run bracketing (RB) mass bias correction method. Sample heterogeneity and detector switching when measuring ²⁰⁸Pb by Q-ICP-MS are identified as sources of reduced analytical performance.     

Isolation and synthesis of pygmanilines,phenylurea derivatives from the Northeastern Atlantic lichen Lichina pygmaea

A library of 864 extracts prepared from Irish marine organisms was screened in the search for novel antioxidants. Chemical investigation of the most promising extract obtained from the common lichen Lichina pygmaea led to the isolation of five resorcinol derivatives. An unusual urea moiety was found embedded in two of these compounds, pygmanilines A (1) and B (2) and their structures were confirmed by one-step chemical syntheses.     

电感耦合等离子体发射光谱法/质谱法检测地衣样品中主次微量元素的方法优化

地衣是应用广泛的大气污染生物监测器。电感耦合等离子体发射光谱法/质谱法(ICP-MS/AES)是植物元素定性定量分析的重要和高效的方法。但受严重大气污染影响,我国部分地区的地衣元素水平远高于其他植物,且在空间、时间、物种和元素类别方面存在巨大差异。虽然地衣在大气污染监测方面具有良好的应用前景,但我国地衣元素分析测试方面尚缺乏专门的方法学研究,这限制了大气质量的地衣生物监测在我国的开展。因此,有必要对地衣样品元素含量的ICP-MS/AES法进行优化。以国家一级标准物质GBW10014(圆白菜)、GBW10015(菠菜)、GBW10052(绿茶)和地衣标准物质(IAEA-336)为材料,探讨了地衣样品的不同消解方法、取样量、分析谱线、同位素、内标元素及仪器参数对ICP-MS和ICP-AES结果的影响。确定了适用于大批量地衣元素测试的干法灰化-碱熔ICP-AES和微波消解ICP-MS的优化条件,该优化条件具有线性关系好(r>0.999 0)、检出限低、准确度高和精密度好的特点。以优化后的测试方法测定采自我国太行山区和南极阿德利岛的地衣样品,结果表明太行山地衣体内元素含量远高于南极阿德利岛,大气沉降对太行山地衣元素组成的相对贡献也较大。验证了优化方法的适用性,为京津冀环境治理提供科学数据和技术支持。     

Biosynthesis of Lichen Substances,Products of a Symbiotic Association

Lichens are composed of algae and fungi living together in symbiotic association and forming characteristic, often polycyclic lichen substances that are rarely encountered in other organisms. While the cultures of the unassociated individual constituents of the lichens can live for an unlimited time some doubt surrounds their viability in nature; their biosynthetic powers are not additive in the lichens. The results concerning the biosynthesis of the lichens that are discussed in the present article were obtained mainly with ¹⁴C-labeled compounds.