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1.
Cilien und Rhizinomorphe entstehen bei Umbilicaria cylindrica aus dem Rindengewebe, wobei ein Zusammenhang mit dem Wachstum der Pruina besteht. Ein ontogenetischer Unterschied zwischen Cilien und Rhizinomorphen besteht nicht. Junge Thallusloben entwickeln sich laminai auf alten Thalli. Hierbei kann der Mutterthallus auf zwei verschiedene Weisen aufgebrochen werden. Anhangsorgane entwickeln sich bevorzugt an Orten starken Thalluswachstums, zu denen neben jungen Loben manchmal auch Fruchtkörperanlagen gehören.  相似文献   

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The antimicrobial properties of acetone, methanol, and aqueous extracts of the lichens Lasallia pustulata, Parmelia sulcata, Umbilicaria crustulosa, and Umbilicaria cylindrica were studied comparatively in vitro. Antimicrobial activities of the extracts of different lichens were estimated by the disk diffusion test for Gram-positive bacteria, Gram-negative bacteria, and fungal organisms, as well as by determining the MIC (minimal inhibitory concentration). The obtained results showed that the acetone and methanol extracts of Lasallia pustulata, Parmelia sulcata, and Umbilicaria crustulosa manifest antibacterial activity against the majority of species of bacteria tested, in addition to selective antifungal activity. The MIC of lichen extracts was lowest (0.78 mg/ml) for the acetone extract of Lasallia pustulata against Bacillus mycoides. Aqueous extracts of all of the tested lichens were inactive. Extracts of the lichen Umbilicaria cylindrica manifested the weakest activity, inhibiting only three of the tested organisms.  相似文献   

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Sterols extracted from Xanthoria parietina with organic solvents and released by saponification of the residual lichen tissue were analysed by GC-MS. The main components of the solvent-extractable sterols were two C28 trienes and those of the more tightly bound sterols were ergost-5-en-3β-ol and two C29 compounds. The structures of the C28 compounds were shown to be ergosta-5,7,22-trien-3β-ol, Ia (ergosterol) and the previously unreported ergosta-5,8,22-trien-3β-ol, IIa, for which the name lichesterol is proposed. The main C29 sterol was identified as (24R)-24-ethylcholesta-5,22-dien-3β-ol (poriferasterol).  相似文献   

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A mixture of C27, C28 and C29 sterols was isolated from the lichen Pseudevernia furfuracea and characterized by means of GLC and MS. Mono-, di- and tri-unsaturated sterols were identified as well as a small amount of fully saturated sterols (stanols). Only a part of the total sterols present in the lichen tissue was easily extractable with organic solvents. Another portion was only obtained after saponification of the lichen residue remaining after extraction with organic solvents. The composition of these two fractions difrered considerably, the former contained predominantly 5a,8a-epidioxy-5a-ergosta-6,22-dien-3β-ol (ergosterol peroxide) and 24-ethylcholesta-5,22-dien-3β-ol while in the latter 24-ethylcholesta-5,22-dien- 3β-ol and C28 triene sterols were the main components.  相似文献   

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Investigation of extracts of Boehmeria cylindrica resulted in identification of cryptopleurine and 3,4-dimethoxy-ω-(2′-piperidyl)acetophenone, known alkaloids, as agents responsible for intense activity against Candida albicans. Julandine, the secophenanthroquinolizidine alkaloid related to cryptopleurine, was also active but not definitely identified in the extracts examined.  相似文献   

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The pythiaceous fungus, Zoophagus insidians synthesizes ergosterol as its dominant sterol. This observation is unusual because the Pythiaceae were previously throught to be incapable of sterol synthesis and the pantonemic fungi in general to not produce ergosterol.  相似文献   

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Inhibitors of the thiol proteinase, papain (EC 3.4.22.2), were shown to be present in 11 species of 10 genera of plants. The inhibitor activity was nondialyzable, and precipitated by ammonium sulfate. Tissue cultures from a number of plant genera consisting of rapidly dividing cells contained latent papain inhibitor that could be activated upon heating. Four isoinhibitors of plant thiol proteinases from seeds of the legume Vigna unguiculata subsp. cyclindrica were purified to apparent homogeneity by acrylamide gel electrophoresis with or without sodium dodecyl sulfate. The inhibitors were present in very small amounts compared to the trypsin inhibitors and the degree of purification of the homogeneous isoinhibitors on the assumption that all were present initially in equal amounts was 15,000- to 60,000-fold. The isoinhibitors did not inhibit pepsin, bromelain, and the serine proteinases, trypsin, chymotrypsin, and subtilisin. They were specific for papain, chymopapain, and ficin but their inhibition of the proteinase, esterase, and amidase activities of the three enzymes differed.  相似文献   

13.
第一次在一个Ae.cylindrica系统中发现了Ph1-like基因,但它的作用略小于Ph1。同时证明了Ae,cylindrica在控制染色体配对基因方面存在多态现象。ph1b基因可以诱导普通小麦与Ae.cylindrica间的部分同源染色体配对,同时用普通小麦对(中国春ph1b突变体×Ae.cylindrica)F_1回交获得了成功。表明利用ph1b基因通过诱导部分同源染色体配对可以把Ae.cylindrica中的有益基因导入到普通小麦中。  相似文献   

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The roots and the aerial parts of M. divaricatum contain a large variety of esterified glycosides of hydroxythymol. Their structures were elucidated mainly by spectroscopic methods.  相似文献   

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Two new compounds isolated from an extract of a Central Asian lichen [Umbilicaria proboscidea (L.) Schrader=Syn.: Gyrophora proboscidea (L.) Ach.] are glucosides with mono- and di-prenylated xanthones as the aglycones and a saccharide moiety from two glucoses linked at C-7. The structures were elucidated on the basis of extensive spectroscopic analysis (1D and 2D NMR, MS, IR and UV) and by hydrolysis.  相似文献   

19.
The investigation of further Othonna species affords 23 new furanoeremophilanes and a new benzofuran-derivative. All these compounds are closely related to those isolated before from other Othonna species. Highly oxidized furanoeremophilanes seem to be typical of this genus.  相似文献   

20.
The investigation of three South American Wedelia species affords besides known acetylenes several new kaurenic acid derivatives, which have been isolated as their methyl esters. Their structures are elucidated by spectroscopic methods. Chemotaxonomic aspects are discussed.  相似文献   

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