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Slobodan Sukdolak - One of the best experts on this subject based on the ideXlab platform.
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Antimicrobial activity of extracts of the lichens Cladonia furcata, Parmelia caperata, Parmelia pertusa, Hypogymnia physodes and Umbilicaria polyphylla
Biologia, 2009Co-Authors: Branislav Ranković, Marijana Mišić, Slobodan SukdolakAbstract:Antimicrobial features of acetone, methanol and aqueous extracts of lichens of Cladonia furcata, Parmelia caperata, Parmelia pertusa, Hypogymnia physodes and Umbilicaria polyphylla were investigated by two different methods at the same time. Testing of antimicrobial activities of extracts from five species of lichens was performed by disc diffusion test in relation to Gram-positive and Gram-negative bacteria and fungal organisms, and through determination of minimal inhibitory concentration (MIC) by Broth Tube Dilution method. The obtained results indicated that acetone and methanol extracts of all investigated lichens in different concentrations manifested selective antibacterial and antifungal activity. That activity was more evident in relation to Gram-positive, than Gram-negative bacteria and fungal organisms. Acetone and methanol extracts of lichens Parmelia pertusa, Hypogymnia physodes and Umbilicaria polyphylla inhibited the growth of all tested microorganisms, most of all of lichens Cladonia furcata and Parmelia caperata . Although, the methanol extracts were generally the most active against the test organisms, the lowest MIC value was measured for acetone extract of species Cladonia furcata 0.39 mg/mL in relation to bacterium Bacillus subtilis . Aqueous extracts of investigated lichens were inactive against all tested organisms.
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the antimicrobial activity of substances derived from the lichens physcia aipolia Umbilicaria polyphylla parmelia caperata and hypogymnia physodes
World Journal of Microbiology & Biotechnology, 2008Co-Authors: Branislav Rankovic, M Misic, Slobodan SukdolakAbstract:In this study, in vitro antimicrobial activity of the physodic acid, usnic acid, atranorin and gyrophoric acid isolated from the lichens Hypogymnia physodes, Parmelia caperata, Physcia aipolia and Umbilicaria polyphylla, has been investigated. An antibiotic assessment was done against six bacteria (three Gram-positive and three Gram-negative) and eight fungi by determining the minimal inhibitory concentration (MIC) by the broth tube dilution method. The tested lichen substances inhibited growth of all the tested microorganisms. The bacteria showed a higher sensitivity against the tested fungi. The highest antimicrobial activity was found in the usnic acid of the Parmelia caperata lichen, where the lowest MIC was 0.0037 mg/ml against the Klebsiella pneumoniae (even lower than the one given by the streptomycin standard). The weakest antimicrobial activity was found in the physodic acid, which inhibited most of the microorganisms in the concentration of 1 mg/ml. Generally, all the components had relatively strong antimicrobial activity against the tested microorganisms, among which were human and animal pathogens. This could be of significance for their use for pharmaceutical purposes.
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antimicrobial activity of extracts of the lichens cladonia furcata parmelia caperata parmelia pertusa hypogymnia physodes and Umbilicaria polyphylla
British Journal of Biomedical Science, 2007Co-Authors: Branislav Rankovic, M Misic, Slobodan SukdolakAbstract:The antimicrobial activity of acetone, methanol and aqueous extracts of the lichens Cladonia furcata, Parmelia caperata, Parmelia pertusa, Hypogymnia physodes and Umbilicaria polyphylla is assessed. The extracts are tested on six species of bacteria and 10 species of fungi using the disk-diffusion method, and broth tube dilution is used to determine minimal inhibitory concentration (MIC). The tested bacteria were more sensitive than the tested fungi. Aqueous extracts of the investigated lichens showed no antimicrobial activity against any of the test organisms, whereas the acetone and methanol extracts showed antimicrobial activity. In general, methanol extracts had stronger activity than did acetone extracts. The strongest activity was recorded for the methanol extract of Parmelia pertusa, which had the lowest measured MIC value (0.78 mg/mL). The least active species was Parmelia caperata (highest MIC value: 50 mg/mL). Bacillus mycoides was the most sensitive of the tested bacterial species, while Candida albicans was the most sensitive fungal species.
Qiming Zhou - One of the best experts on this subject based on the ideXlab platform.
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distribution patterns of haplotypes for symbionts from Umbilicaria esculenta and u muehlenbergii reflect the importance of reproductive strategy in shaping population genetic structure
BMC Microbiology, 2015Co-Authors: Shunan Cao, Fang Zhang, Chuanpeng Liu, Zhihua Hao, Yuan Tian, Lingxiang Zhu, Qiming ZhouAbstract:The diversity of lichen fungal components and their photosynthetic partners reflects both ecological and evolutionary factors. In present study, molecular investigations of the internal transcribed spacer of the nuclear ribosomal DNA (ITS nrDNA) region were conducted to analyze the genetic diversity of Umbilicaria esculenta and U. muehlenbergii together with their associated green algae. It was here demonstrated that the reproductive strategy is a principal reason for fungal selectivity to algae. U. muehlenbergii, which disperses via sexual spores, exhibits lower selectivity to its photosynthetic partners than U. esculenta, which has a vegetative reproductive strategy. The difference of genotypic diversity (both fungal and algal) between these two Umbilicaria species is low, although their nucleotide diversity can vary greatly. The present study illustrates that lichen-forming fungi with sexual reproductive strategies are less selective with respect to their photobionts; and reveals that both sexual and vegetative reproduction allow lichens to generate similar amounts of diversity to adapt to the environments. The current study will be helpful for elucidating how lichens with different reproductive strategies adapt to changing environments.
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Additional file 1: Table S1. of Distribution patterns of haplotypes for symbionts from Umbilicaria esculenta and U. muehlenbergii reflect the importance of reproductive strategy in shaping population genetic structure
2015Co-Authors: Shunan Cao, Fang Zhang, Chuanpeng Liu, Zhihua Hao, Yuan Tian, Lingxiang Zhu, Qiming ZhouAbstract:Haplotypes information of Umbilicaria and other six lichen genera across six sites. Table S2. Sequences retrieved from Genbank. Table S3. Primers used in this study. (DOC 285 kb
Stojanović Gordana - One of the best experts on this subject based on the ideXlab platform.
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Biological activities of Umbilicaria crustulosa (Ach.) frey acetone extract
Serbian Chemical Society, 2017Co-Authors: Zlatanović Ivana, Stanković Miroslava, Mitić Violeta, Stankov-jovanović Vesna, Zrnzević Ivana, Đorđević Aleksandra, Stojanović GordanaAbstract:This paper reports for the first time the effect of an acetone extract of Umbilicaria crustulosa on the micronucleus distribution of human lymphocytes, and on the cholinesterase activity and antioxidant activity by the cupric ion reducing antioxidant capacity (CUPRAC) method. Additionally, the total phenolic compounds (TPC) and the antioxidant properties were estimated via DPPH, ABTS and TRP assays. Moreover, the antibacterial activity against two Gram-positive and three Gram-negative bacteria were determined. Acetone extract of U. crustulosa at concentration of 1 and 2 μg mL-1 decreased a frequency of micronuclei (MN) by 10.8 and 16.8 %, respectively, acting more or slightly less than the synthetic protector amifostine (AMF, WR-2721, 11.4 %, at concentration of 1 μg mL-1). The tested extract did not inhibit cholinesterase activity nor did it exhibit activity toward the examined bacteria. The extract reduced the concentration of DPPH and ABTS radicals by 88.7 and 96.2 %, respectively. Values for total reducing power (TRP) and cupric reducing capacity (CUPRAC) were 0.6197±0.0166 μg ascorbic acid equivalents (AAE) per mg of dry extract, and 19.7641±1.6546 μg trolox equivalents (TE) per mg of dry extract, respectively. The total phenol content was 350.4188 ±14.587 μg gallic acid equivalents (GAE) per mg of dry extract. The results of the present study showed that U. crustulosa acetone extract is a promising candidate for in vivo experiments considering its antioxidant activity and protective effect on human lymphocytes. [Projekat Ministarstva nauke Republike Srbije, br. 172047
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IZOLOVANJE I IDENTIFIKACIJA SEKUNDARNIH METABOLITA VRSTE Umbilicaria CRUSTULOSA (ACH.) FREY
'University of Nis - Faculty of Philosophy', 2016Co-Authors: Zlatanović Ivana, Zrnzević Ivana, Petrović Goran, Jovanović Olga, Stojanović GordanaAbstract:Herein, we have studied secondary metabolites of Umbilicaria crustulosa (Ach.) Frey. By using preparative HPLC, four compounds were isolated from the U. crustulosa methanol extract. The structure of isolated lichen substances was determined on the basis of their 1H, 13C and 2D NMR spectra as follows: methyl orsellinate, lecanoric acid, methyl lecanorate and gyrophoric acid. In addition to methanol, the composition of acetone and ethanol extracts were also studied (analytical HPLC). Relative distributions (%) of the detected constituents were as follows (in methanol/acetone/ethanol extracts): methyl orsellinate (5.7/1.5/0.9), lecanoric acid (17.9/5.7/6.7), crustinic acid (8.0/2.8/2.5), methyl lecanorate (4.8/0/0) and gyrophoric acid (59.2/78.0/85.7). A significant difference in the chemical profiles of the studied extracts was in the presence/absence of methyl esters of lichen acids. Nonetheless, the chemical composition of the ethanol extracts (no ethyl esters were detected) and the fact that treatment of acetone and ethanol extracts with methanol does not lead to changes in their composition suggests that methyl esters were not artifacts of the isolation procedure. The lower content of methyl orsellinate and the absence of methyl lecanorate from acetone and ethanol extracts may be the result of different solubilities of these compounds in methanol, ethanol and acetone.U ovom radu, ispitivani su sekundarni metabolite vrste lišaja Umbilicaria crustulosa (Ach.) Frey. Primenom preparativne HPLC metode izolovana su 4 jedinjenja iz metanolnog ekstrakta U. crustulosa. Na osnovu rezultata 1H, 13C i 2D-NMR eksperimenata, utvrđeno je das u ova jedinjenja: metil-orselinat, lekanorna kiselina, metil-lekanorat i giroforna kiselina. Pored metanolnog, analiziran je i hemijski sastav acetonskog i etanolnog ekstrakta (analitička HPLC analiza). Procentna zastupljenost (%) detektovanih sastojaka bila je sledeća () u metanolnom/acetonskom/etanolnom ekstraktu): metil-orselinat 5.7/1.5/0.9), lekanorna kiselina ((17.9/5.7/6.7), krustinska kiselina (8.0/2.8/2.5), metil-lekanorat (4.8/0/0) i giroforna kiselina (59.2/78.0/85.7). Značajnu razliku u hemijskom profilu proučavanih ekstrakata činilo je pisustvo/otsustvo estara lišajevskih kiselina. Ipak, na osnovu hemijskog sastava etanolnog ekstrakta (nisu detektovani odgovarajući etil-estri) i činjence da tretiranje acetonskog i etanolnog ekstrakta metanolom ne dovodi do promena u njihovom sastavu, izgleda da detektovani metil-estri nisu artefakti nastali u toku ekstrakcije. Manji sadržaj metilorsenilata i odsustvo metil-lekanorata u acetonskom i etanolnom ekstraktu u odnosu na metanolni je verovatno posledica različite rastvorljivosti ovih jedinjenja u metanolu, etanolu i acetonu
S Ott - One of the best experts on this subject based on the ideXlab platform.
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metabolic response to desiccation stress in strains of green algal photobionts trebouxia from two antarctic lichens of southern habitats
Phycologia, 2016Co-Authors: Andres Sadowsky, Tabea Mettleraltmann, S OttAbstract:Abstract: Desiccation tolerance is a feature of most lichens. These symbiotic associations of a fungal partner (mycobiont) and a photosynthetic partner (photobiont) experience severe desiccation on a regular basis. Many lichen species colonise extreme habitats, such as the cold deserts of Antarctica. Although the stress physiology of lichens has been studied extensively, little is known about the photobionts' physiological potential. To assess the contribution of photobionts to lichen success in Antarctic terrestrial environments, the photosynthetic partners of Umbilicaria decussata (Umbilicariaceae, lichenised ascomycetes) and Usnea lambii (Parmeliaceae, lichenised ascomycetes) from extreme habitats in southern Antarctica were isolated. Significant differences regarding stress tolerance of the two green algae had been shown previously despite their close phylogenetic relationship. A deeper understanding and explanation of these differences were obtained by examination of the metabolite profiles and dynam...
Branislav Rankovic - One of the best experts on this subject based on the ideXlab platform.
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the antimicrobial activity of substances derived from the lichens physcia aipolia Umbilicaria polyphylla parmelia caperata and hypogymnia physodes
World Journal of Microbiology & Biotechnology, 2008Co-Authors: Branislav Rankovic, M Misic, Slobodan SukdolakAbstract:In this study, in vitro antimicrobial activity of the physodic acid, usnic acid, atranorin and gyrophoric acid isolated from the lichens Hypogymnia physodes, Parmelia caperata, Physcia aipolia and Umbilicaria polyphylla, has been investigated. An antibiotic assessment was done against six bacteria (three Gram-positive and three Gram-negative) and eight fungi by determining the minimal inhibitory concentration (MIC) by the broth tube dilution method. The tested lichen substances inhibited growth of all the tested microorganisms. The bacteria showed a higher sensitivity against the tested fungi. The highest antimicrobial activity was found in the usnic acid of the Parmelia caperata lichen, where the lowest MIC was 0.0037 mg/ml against the Klebsiella pneumoniae (even lower than the one given by the streptomycin standard). The weakest antimicrobial activity was found in the physodic acid, which inhibited most of the microorganisms in the concentration of 1 mg/ml. Generally, all the components had relatively strong antimicrobial activity against the tested microorganisms, among which were human and animal pathogens. This could be of significance for their use for pharmaceutical purposes.
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antimicrobial activity of extracts of the lichens cladonia furcata parmelia caperata parmelia pertusa hypogymnia physodes and Umbilicaria polyphylla
British Journal of Biomedical Science, 2007Co-Authors: Branislav Rankovic, M Misic, Slobodan SukdolakAbstract:The antimicrobial activity of acetone, methanol and aqueous extracts of the lichens Cladonia furcata, Parmelia caperata, Parmelia pertusa, Hypogymnia physodes and Umbilicaria polyphylla is assessed. The extracts are tested on six species of bacteria and 10 species of fungi using the disk-diffusion method, and broth tube dilution is used to determine minimal inhibitory concentration (MIC). The tested bacteria were more sensitive than the tested fungi. Aqueous extracts of the investigated lichens showed no antimicrobial activity against any of the test organisms, whereas the acetone and methanol extracts showed antimicrobial activity. In general, methanol extracts had stronger activity than did acetone extracts. The strongest activity was recorded for the methanol extract of Parmelia pertusa, which had the lowest measured MIC value (0.78 mg/mL). The least active species was Parmelia caperata (highest MIC value: 50 mg/mL). Bacillus mycoides was the most sensitive of the tested bacterial species, while Candida albicans was the most sensitive fungal species.