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1.
Twenty-five Frullania species (liverworts) were chemically investigated. Fourteen species produce allergy-inducing sesquiterpene lactones. Eighteen species contain bibenzyls. The sesquiterpene lactones and bibenzyls are obtained as the major components and they are valuable chemosystematic markers of Frullania species. On the basis of their chemical constituents, Frullania species can be divided into five chemotypes: sesquiterpene lactone-bibenzyl type; sesquiterpene lactone type; bibenzyl type; monoterpene type and cyclocolorenone type.  相似文献   

2.
Two new bibenzyls have been isolated from Radula complanata and their structures have been elucidated by chemical and spectral evidence. In addition to the above two bibenzyls and four known bibenzyls, two new acidic bibenzyls have been isolated as their methyl esters.  相似文献   

3.
Three liverworts, Trichocolea tomentella, Neotrichocolea bissethii and Trichocoleopsis sacculata belonging to Jungermanniales were chemically investigated. Isoprenyl benzoates are the important chemical markers of Trichocolea tomentella. Neotrichocolea bissethii elaborates sesquiterpenes as the major components. The sacculatane-type diterpenes and pinguisane-type sesquiterpenes are the significant chemosystematic markers of Trichocoleopsis sacculata. These three species are chemically quite different. Trichocoleopsis sacculata is chemically rather close to Porella species. The present chemical results support the recent morphological classification of the above three species proposed by Schuster. Some species of Jungermanniales are chemically identical to those of Metzgeriales and these results also support the phylogenetic classification in which the two orders have been united within the subclass Jungermanniae.  相似文献   

4.
Six new bibenzyls have been isolated from the liverwort, Radula variabilis and their structures have been established by chemical and spectral evidence. In addition, a new dihydrochalcone and a new bibenzy] have been isolated as their methyl ethers. Except for two of the bibenzyls, the present compounds have a unique seven-membered heterocyclic ring and they are the first members of a new group of natural product.  相似文献   

5.
Four novel prenyl bibenzyls, perrottetin A–D were isolated from the liverwort Radula perrottetii together with a new sesquiterpene phenol, ent-2, 3-dihydroxycuparene and a prenyl dihydrochalcone, and their structures were determined by spectral methods and chemical transformations. Further investigation of the French species R. complanata resulted in the isolation of four new bibenzyls, 3, 4′-dimethoxybibenzyl, 3,5-dihydroxy-4-(2, 3-epoxy-3-methylbutyl)bibenzyl, radulanin H and radulanolide. R. buccinifera was chemically close to R. complanata. The composition of bibenzyls found in R. perrottetii and R. oyamensis were different from that of the other Radula species referred to in the section Radula. Some prenyl bibenzyls showed antimicrobial activity against Streptococcus aureus (20 μg/ml). The allergenic activity of R. complanata is due to (+)-frullanolide from the liverwort Frullania dilatata which is intermingled in R. complanata.  相似文献   

6.
A series of ent-sesquiterpenoids corresponding to the optical antipodes of those in higher plants have been isolated from the liverwort Marchantia polymorpha. These sesquiterpenoids provide yet another example of the peculiar stereospecificity of the biogenesis of the liverwort sesquiterpenoids and suggest a special taxonomic position of the liverworts in the plant kingdom.  相似文献   

7.
A new bibenzyl having a dihydrooxepin ring was isolated from the acetone extract of the liverwort Radula tokiensis, together with the previously known 5 bibenzyls and 3 sesquiterpenes, trans-β-farnesene, cuparene and (Jcuparenol. Two known bibenzyls were isolated from R. japonica. The bibenzyl derivatives are significant chemosystematic markers of the Radulaceae.  相似文献   

8.
The chemical constituents of the volatile oils from Chrysanthemum indicum, C. yoshinaganthum and C. cuneifolium, three botanically related tetraploid species, are described. By spectroscopic methods, 42 compounds were identified, including 22 monoterpenoids, 17 sesquiterpenoids and 3 acetylenic compounds. The sesquiterpenoids estafiatin (C. yoshinaganthum) and valeranone (C. indicum) have been found for the first time in Chrysanthemum species.  相似文献   

9.
Amber is renowned for the exceptional preservation state of its inclusions, allowing detailed morphological analysis and providing relevant environmental, palaeoecological, geographical, and geological information. Amber deposits are predominantly known from North America, Europe, and Asia, and are considered to be rare on the continents that formed Gondwana. The recent discovery of fossiliferous amber deposits in Ethiopia, therefore, provides an inimitable opportunity to close gaps in the fossil record of African terrestrial biota and to study organisms which are otherwise rare in the fossil record. Here we show that diverse cryptogams are preserved in highest fidelity in Miocene Ethiopian amber. We describe gametophyte fragments of four liverworts: Thysananthus aethiopicus sp. nov. (Porellales, Lejeuneaceae), Lejeunea abyssinicoides sp. nov. (Porellales, Lejeuneaceae), Frullania shewanensis sp. nov. (Porellales, Frullaniaceae), and Frullania palaeoafricana sp. nov. (Porellales, Frullaniaceae). Furthermore, we describe a pleurocarpous moss of the extant genus Isopterygium (Hypnales, Pylaisiadelphaceae) and a lichen representing the order Lecanorales. These new specimens represent the first amber fossils of liverworts, mosses, and lichens from the African continent and render Ethiopian amber as one of the few worldwide amber deposits preserving bryophytes (mosses and liverworts) or lichens. Fossil species of Thysananthus were recorded in Eocene Baltic and Oligocene Bitterfeld as well as Miocene Dominican and probably also Miocene Mexican ambers. Fossils that can unequivocally be assigned to Lejeunea have only been found in Dominican amber so far. Neotropical ambers contain only one taxon of Frullania to date, while the genus is most diverse in Baltic, Bitterfeld, and Rovno ambers, formed in temperate regions. The new fossils support a tropical to subtropical origin of Ethiopian amber. The new African liverwort fossils are included in an updated list of leafy liverworts described from worldwide Cenozoic ambers to date.  相似文献   

10.
采用正己烷萃取法,结合GC-MS(气相色谱-质谱联用)技术,并通过谱库、保留指数和文献检索定性,内标法定量,分析9种唇形科芳香植物叶片的挥发性萜类成分并比较其差异,所得结果不仅为芳香植物的高效利用、合理开发提供参考,还为植物萜类的代谢研究提供依据。结果显示:从9种芳香植物中共检测到77种挥发性萜类物质,藿香中检测到的种类最多,为46种,迷迭香(35种)、百里香(33种)、药用鼠尾草(33种)和美国薄荷(31种)次之,石竹烯和蛇麻烯为9种植物共有成分。迷迭香中检测到的挥发性萜类的含量最高,其次是药用鼠尾草和藿香。单萜类成上分明显高于倍半萜类,因此迷迭香、药用鼠尾草、藿香、百里香和美国薄荷,较适宜作为提取挥发性萜类的材料;香蜂花只适宜柠檬醛的提取,牛至、凤梨鼠尾草和南欧丹参不适宜作为提取挥发性萜类的材料。上述芳香植物在正常环境中生成单萜类化合物的能力高于生成倍半萜类化合物的能力,可能与其含有的萜类合酶有关。  相似文献   

11.
Four liverworts, Marchantia berteroana, M. foliacea, Plagiochila stephensoniana and Porella elegantula collected in New Zealand were chemically investigated. M. berteroana contains cuparene and (?)-2-hydroxycuparene as the major components. γ-Cadinene is the major component of M. foliacea. 4-Hydroxy-3′-methoxybibenzyl is a chemical marker for P. stephensoniana which belongs to the non-pungent type of Plagiochila species. P. elegantula synthesizes perrottetianal and belongs to the non-pungent type of Porella species.  相似文献   

12.
13.
Vasorelaxant effects of a series of bis(bibenzyls) from liverworts such as Marchantia polymorpha and Marchantia paleacea on rat aorta demonstrated that they relaxed phenylephrine (PE)-induced contractions, which may be mediated through the increased release of NO from endothelial cells as well as opening of K(+) channels, and inhibition of Ca(2+) influx through voltage-dependent Ca(2+) channels (VDCs) and/or receptor-operated Ca(2+) channels (ROCs). Structure-activity relationship based on their structures was discussed. The presence of two aromatic rings which can be connected through two atoms bridge spacer may play an important role for vasorelaxant effect.  相似文献   

14.
The drimane-type sesquiterpenoids (-)-polygodial (1), (-)-isopolygodial (4), drimenin (5), and isodrimenin (6) were isolated from a pungent Argentine collection of the fern Thelypteris hispidula, along with other terpenoids. As the mentioned drimanes have been previously found in liverworts, the present results strongly support the theory that Pteridophytes and Bryophytes share the same line of evolution. Our present investigations indicate that two chemotypes of T. hispidula are widespread in the northwest of Argentina. Plants belonging to the pungent chemotype contain drimanes, while nonpungent plants lack drimanes.  相似文献   

15.
The volatile components of 25 taxa of the liverwort family Frullaniaceae from New Zealand, Australia and South America have been analyzed by GC-MS. The present Frullania species are chemically divided into five major types: (1) sesquiterpene lactones, (2) sesquiterpene lactones-bibenzyls, (3) bibenzyls, (4) 2-alkanone and (5) triterpene types; the latter two chemo-types are newly proposed for the genus. Schusterella chevalierii, belonging to the Frullaniaceae, is closely related chemically to the sesquiterpene lactone type of the Frullania species since it elaborates two eudesmanolides, beta-cyclocostunolide and dihydro-beta-cyclocostunolide as major components.  相似文献   

16.
本文报道钱江源国家公园叶附生苔类植物4科9属19种, 较之前记录增加3科8属17种。与钱江源处于同纬度的我国其他地区相比, 钱江源叶附生苔类植物的种数仅次于西藏墨脱, 排名第二。鳞叶疣鳞苔(Cololejeunea longifolia)和尖叶薄鳞苔(Leptolejeunea subacuta)是钱江源国家公园最常见的2种叶附生苔类植物。丰富的叶附生苔类植物表明钱江源国家公园具有较合适的叶附生苔类植物生长环境, 这可能与该地区长期有效的保护密切相关。  相似文献   

17.
Three germacrane-type sesquiterpenoids, (+)-germacrone-4,5-epoxide, germacrone and (+)-curdione were biotransformed by Aspergillus niger to give hydroxylated guaiane-type sesquiterpenoids together with allylic alcohols and spirolactone.  相似文献   

18.
The antifungal activity of natural sesquiterpenoids patchoulol, ginsenol, cedrol and globulol against the fungus Botrytis cinerea has been determined. The diminishing of the effect after 3–6 days suggests that a mechanism of detoxification is present. Biotransformation of these fungistatic compounds has been investigated as a method of studying this mechanism.  相似文献   

19.
刘润  张朝晖  申家琛  王智慧 《生物多样性》2018,26(12):1277-1972
岩溶洞穴的开发与利用导致的重金属污染严重威胁洞穴环境及地下水, 因此对洞穴环境的监测具有重要的现实意义。本文通过对典型的暗河型溶洞贵州织金洞内的苔藓群落特征及其重金属污染状况进行研究, 拟揭示苔藓群落对洞穴重金属污染的指示意义。共发现苔藓群落类型34个, 苔藓植物种类20科33属49种, 含苔类8科8属12种, 藓类12科25属37种。优势科为丛藓科、凤尾藓科和提灯藓科, 物种占比率分别为16%、14%、14%。Hg污染超标倍数最高达59.45倍, 在距洞口不同深度均远高于Cr和Zn, 说明洞内Hg污染较为严重。苔藓群落指标随着重金属污染含量的上升总体呈下降趋势。所测定的重金属中基质Hg含量与苔藓群落指标的拟合程度最好, 与其对应的苔藓群落指标均呈显著负相关关系(P < 0.05), 说明苔藓群落特征能够很好地反映洞内Hg污染的变化趋势。RDA排序结果分析表明: 洞穴苔藓群落为适应低光度环境会表现出向光性运动、喜钙生基质、耐重金属等生理特征。蛇苔(Conocephalum conicum)植物体内的Hg含量与其基质Hg含量具有显著相关性(P < 0.05), 说明蛇苔受基质Hg污染影响较大。在今后的治理过程中, 可以考虑将蛇苔作为洞内环境的生物监测材料之一。  相似文献   

20.
广东八宝山叶附生苔的研究   总被引:6,自引:0,他引:6  
  相似文献   

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