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11.
Eight lichen species, Cetraria aculeata, Cladonia furcata, Pseudephebe pubescens, Sphaerophorus globosus, Stereocaulon alpinum, Umbilicaria antarctica, Usnea antarctica and Usnea aurantiacoatra, were collected from King George Island, maritime Antarctica, for the evaluation of antioxidant activities. Anti-linoleic acid peroxidation activity, free radical scavenging activity, reducing power and superoxide anion scavenging activity were assessed of methanol and acetone extract of the lichens in vitro. Extract of Umbilicaria antarctica, Cladonia furcata, Sphaerophorus globosus and Usnea antarctica were found to have strong in vitro antioxidant properties. In general, acetone extract exhibited stronger activities than methanol extract. The activity-guided bioautographic TLC and HPLC analysis demonstrated that lecanoric acid was the main antioxidant compound in the acetone extract of Umbilicaria antarctica, the most potent antioxidant lichen species among the test species. The results suggested that several Antarctic lichens and their substances can be used as novel bioresources of natural antioxidants.  相似文献   
12.
The aim of this study was to evaluate the antioxidant properties of an edible lichen Ramalina conduplicans. The extract exhibited potent anti-linoleic acid peroxidation activity, free radical-scavenging activity, and reducing power. The total phenolic contents were found to be high in the extract. Activity-guided bioautographic thin layer chromatography (TLC) and HPLC identified sekikaic acid and homosekikaic acid as the main free radical-scavenging compounds in R. conduplicans extract (IC50 [50% inhibition concentration] = 0.082 and 0.276 mg/ml, respectively). The results suggested that this edible lichen species have the potential to be utilized as food additives or as protective drugs.  相似文献   
13.
A new species of Kisaura Ross (Philopotamidae) from Japan and a new species of Psychomyia Latreille (Psychomyiidae) from Russia are described. Kisaura imparis n. sp. is closest to Kisaura aurascens (Martynov, 1934), but the lateral processes of tergum X are asymmetrical and the apex of tergum X is different. Psychomyia poltavkaensis n. sp. resembles Psychomyia n. sp., but the shape of tergum IX+X is more rounded, the apex of the basoventral process of each preanal appendage is unforked, and the inferior appendages are branched.  相似文献   
14.
Fifty-six species in 36 genera of macrolichens are reported from the Zhongdian area, northwest Yunnan, China during the lichenological expedition for highland macrolichen survey in June, 2004. More than 60% of these species have not been reported in South Korea. All of the 182 collected specimens are deposited in the Korean Lichen Research Institute (KoLRI) at Sunchon National University in Korea, and some of them are duplicated in the lichen herbarium, Crytogamic Herbarium, Kunming Institute of Botany, Academia Sinica (KUN-L) in China. This is the first report on the macrolichen flora in the visited areas.  相似文献   
15.
This study reports, for the first time, the investigation of the distribution of Korean saxicolous lichens in the coastal rocks of U-do islet, which is known as an unpolluted zone in Jeju. More than thirty lichens were obtained and investigated from the coastal rocks frequently contacted by seawater. A molecular analysis using PCR amplification of the rRNA ITS regions revealed the coastal rock lichens could be placed into 8 families and 14 genera, Ramalinaceae (Bacidia, Ramalina), Physciaceae (Buellia, Dirinaria, Phaeophyscia, Physcia, Pyxine), Lecanoraceae (Candelaria, Lecanora), Parmeliaceae (Xanthoparmelia), Graphidaceae (Graphis), Pertusariaceae (Pertusaria), Rhizocarpaceae (Rhizocarpon), and Teloschistaceae (Caloplaca), showing a diversity of lichens, with foliose (flat leaf-like), crustose (crust-like), and fruticose (miniature shrub-like) life forms might be distributed in the coastal rocks. These findings suggested the possibility that the lichens identified in the present work might be resistant to a salty environment.  相似文献   
16.
Lichens produce various unique chemicals that can be used for pharmaceutical purposes. To screen for novel lichen secondary metabolites showing inhibitory activity against lung cancer cell motility, we tested acetone extracts of 13 lichen samples collected in Chile. Physciosporin, isolated from Pseudocyphellaria coriacea (Hook f. & Taylor) D.J. Galloway & P. James, was identified as an effective compound and showed significant inhibitory activity in migration and invasion assays against human lung cancer cells. Physciosporin treatment reduced both protein and mRNA levels of N-cadherin with concomitant decreases in the levels of epithelial-mesenchymal transition markers such as snail and twist. Physciosporin also suppressed KITENIN (KAI1 C-terminal interacting tetraspanin)-mediated AP-1 activity in both the absence and presence of epidermal growth factor stimulation. Quantitative real-time PCR analysis showed that the expression of the metastasis suppressor gene, KAI1, was increased while that of the metastasis enhancer gene, KITENIN, was dramatically decreased by physciosporin. Particularly, the activity of 3’-untranslated region of KITENIN was decreased by physciosporin. Moreover, Cdc42 and Rac1 activities were decreased by physciosporin. These results demonstrated that the lichen secondary metabolite, physciosporin, inhibits lung cancer cell motility through novel mechanisms of action.  相似文献   
17.
Lichens are symbiotic organisms which produce distinct secondary metabolic products. In the present study, we tested the cytotoxic activity of 17 lichen species against several human cancer cells and further investigated the molecular mechanisms underlying their anti-cancer activity. We found that among 17 lichens species, F. cucullata exhibited the most potent cytotoxicity in several human cancer cells. High performance liquid chromatography analysis revealed that the acetone extract of F. cucullata contains usnic acid, salazinic acid, Squamatic acid, Baeomycesic acid, d-protolichesterinic acid, and lichesterinic acid as subcomponents. MTT assay showed that cancer cell lines were more vulnerable to the cytotoxic effects of the extract than non-cancer cell lines. Furthermore, among the identified subcomponents, usnic acid treatment had a similar cytotoxic effect on cancer cell lines but with lower potency than the extract. At a lethal dose, treatment with the extract or with usnic acid greatly increased the apoptotic cell population and specifically activated the apoptotic signaling pathway; however, using sub-lethal doses, extract and usnic acid treatment decreased cancer cell motility and inhibited in vitro and in vivo tumorigenic potentials. In these cells, we observed significantly reduced levels of epithelial-mesenchymal transition (EMT) markers and phosphor-Akt, while phosphor-c-Jun and phosphor-ERK1/2 levels were only marginally affected. Overall, the anti-cancer activity of the extract is more potent than that of usnic acid alone. Taken together, F. cucullata and its subcomponent, usnic acid together with additional component, exert anti-cancer effects on human cancer cells through the induction of apoptosis and the inhibition of EMT.  相似文献   
18.
Aspicilia humida Lee is described as a new lichen-forming fungus from a wetland forest, South Korea. The new species is distinguishable from Aspicilia aquatica (Fr.) Körb., the most similar species, by the absence of prothallus, black disk without green color in water, olive-brown epihymenium, shorter hymenium, hymenium I + yellowish blue-green, wider paraphysial tips without a vivid pigment, smaller asci, smaller ascospores, and the presence of stictic acid. Molecular analyses employing internal transcribed spacer (ITS) and mitochondrial small subunit (mtSSU) sequences strongly support A. humida as a distinct species in the A. cinerea group. A surrogate key is provided to assist in the identification of all 28 aspicilioid species of Korea.  相似文献   
19.
对云南茶叶农场中的附生地衣进行调查发现: 附生在茶树上的地衣有25 属, 51 种; 其中, 45 种是首次报道附生在茶树上, 包括2 个中国新记录种: 癞屑衣( Lepraria lobificans) 和阿曼原胚衣( Protoblastenia amagiensis) , 以及20 个云南新分布种。壳状地衣的共生菌丝侵入茶叶树干外皮层组织, 在生长过程中产生地衣酸, 一定程度的加速了农场中茶树的老化; 靠近茶树发芽点生长的壳状地衣和叶状地衣, 造成芽体发育不良, 对茶叶的产量和品质有一定影响。  相似文献   
20.
报道了宁夏沙坡头沙漠地区地衣3个中国新记录种:Fulgensia desertorum,Rinodina bischoffii和Seirophora orientalis,描述了3种地衣的表型特征,生态学特征及分布情况。  相似文献   
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