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Lecanora
About: Lecanora is a research topic. Over the lifetime, 445 publications have been published within this topic receiving 5205 citations.
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TL;DR: Axenic cultures ofLichen photobionts isolated from bark-inhabiting lichen thalli of the Physcietum adscendentis Ochsner were identified by light microscopy and sequence comparisons of internal transcribed spacer rDNAs to investigate principles of lichenization within a defined lichen sociological unit to support the assumption that Xanthoria parietina takes over its algal partner from a Physcia species.
Abstract: Axenic cultures of lichen photobionts isolated from bark-inhabiting lichen thalli of the Physcietum adscendentis Ochsner were identified by light microscopy and sequence comparisons of internal transcribed spacer rDNAs to investigate principles of lichenization within a defined lichen sociological unit. The photobiont identity of eight lichen species is reported for the first time (photobiont species in square brackets): Lecania cyrtella (Ach.) Th. Fr. [Trebouxia arboricola Puym.], Lecania naegelii (Hepp) Diederich & v. d. Boom [Dictyochloropsis symbiontica Tscherm.-Woess], Candelaria concolor (Dicks) B. Stein [Trebouxia jamesii (Hildreth & Ahmadjian) Gartner], Candelariella cf. reflexa (Nyl.) Lettau [T. jamesii], Lecanora spec. [T. arboricola], Phaeophyscia orbicularis (Neck.) Moberg [T. impressa Ahmadjian], Physcia adscendens (Fr.) H. Olivier [T. impressa] and Lecidella elaeochroma (Ach.) M. Choisy [T. arboricola] and could be confirmed for another two species, Physcia stellaris (L.) Nyl. [Trebouxia impressa] and Xanthoria parietina (L.) Th. Fr. [Trebouxia arboricola]. The observation that pioneer lichens without vegetative propagules, growing on smooth bark, had Trebouxia arboricola as photobiont can be explained by the assumption of a free-living population of Trebouxia arboricola. Species of photobionts from Xanthoria parietina were morphologically and genetically different from those of Physcia adscendens and Phaeophyscia orbicularis, respectively; a finding that does not support the previous assumption that Xanthoria parietina takes over its algal partner from a Physcia species, at least at the sites investigated.
164 citations
TL;DR: The present study shows that tested lichen extracts demonstrated a strong antioxidant, antimicrobial and anticancer effects, which suggest that lichens may be used as as possible natural antioxidant and antimicrobial agents to control various human, animal and plant diseases.
Abstract: The aim of this study is to investigate in vitro antioxidant, antimicrobial and anticancer activity of the acetone extracts of the lichens Cladonia furcata, Lecanora atra and Lecanora muralis Antioxidant activity was evaluated by five separate methods: free radical scavenging, superoxide anion radical scavenging, reducing power, determination of total phenolic compounds and determination of total flavonoid content The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method against six species of bacteria and ten species of fungi Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using MTT method Of the lichens tested, Lecanora atra had largest free radical scavenging activity (947% inhibition), which was greater than the standard antioxidants Moreover, the tested extracts had effective reducing power and superoxide anion radical scavenging The strong relationships between total phenolic and flavonoid contents and the antioxidant effect of tested extracts were observed Extract of Cladonia furcata was the most active antimicrobial agent with minimum inhibitory concentration values ranging from 078 to 25 mg/mL All extracts were found to be strong anticancer activity toward both cell lines with IC50 values ranging from 851 to 4022 μg/mL The present study shows that tested lichen extracts demonstrated a strong antioxidant, antimicrobial and anticancer effects That suggest that lichens may be used as as possible natural antioxidant, antimicrobial and anticancer agents to control various human, animal and plant diseases
95 citations
TL;DR: A phylogenetic analysis based on 16S rRNA gene sequence of 30 bacterial strains isolated from five epilithic lichens belonging to four species shows that these represent the main bacterial lineages Actinobacteria, Firmicutes, Proteobacteria and Deinococcus-Thermus.
Abstract: Antarctic habitats harbour yet unexplored niches for microbial communities. Among these, lichen symbioses are very long-living and stable microenvironments for bacterial colonization. In this work, we present a first assessment of the culturable fraction of bacteria associated with Antarctic lichens. A phylogenetic analysis based on 16S rRNA gene sequence of 30 bacterial strains isolated from five epilithic lichens belonging to four species (Lecanora fuscobrunnea, Umbilicaria decussata, Usnea antarctica, Xanthoria elegans) shows that these represent the main bacterial lineages Actinobacteria, Firmicutes, Proteobacteria and Deinococcus-Thermus. Within the Actinomycetales, two strains group in the genera Arthrobacter and Knoellia, respectively. Most of the other Actinobacteria form well-supported groups, but could be assigned with certainty only at the family level, and one is in isolated position in the Mycobacteriaceae. The strains in Firmicutes and Proteobacteria belong to the genera Paenibacillus,Bacillus and Pseudomonas, which were already reported from lichen thalli. Some genera such as Burkholderia and Azotobacter, reported in the literature as also associated with lichens, have not been detected in this study. One strain represents the first record of Deinococcus in epilithic lichens; it is related to the species Deinococcus alpinitundrae from Alpine environments and may represent a new species. Further separated and well-supported clades indicate the presence of possibly new entities. Some of the examined strains are related to known psychrophilic bacteria isolated from ice and other extreme environments, others with bacteria distributed worldwide even in temperate climates. Most of the strains tested were able to grow at low temperatures, but tolerated a wider range of temperature. Ecological and evolutionary implications of these lichen-associated bacteria are discussed.
84 citations
TL;DR: A comparative review of 57 Lepraria species and 2 varieties is provided together with species descriptions and a key and Lecanora leuckertiana is transferred to LepRaria.
Abstract: A comparative review of 57Lepraria species and 2 varieties is provided together with species descriptions and a key. Lecanora leuckertiana is transferred to Lepraria. In addition some putative taxa by different authors are discussed. ducing anthraquinones to Caloplaca Th. Fr. and Leproplaca (Nyl.) Nyl. ex Hue (a current synonym of Caloplaca) and species contain- ing pulvinic acid derivatives to Chrysothrix Mont. The number of species in Lepraria was further reduced when taxa producing dibenzofuranes were placed in Leproloma Nyl. ex Cromb. (Laundon 1989; Leuckert & Kummerling 1991). The concept of the
80 citations