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1.
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
2.
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
3.
Heng Luo Yoshikazu Yamamoto Jung A Kim Jae Sung Jung Young Jin Koh Jae-Seoun Hur 《Polar Biology》2009,32(7):1033-1040
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
4.
Branislav Ranković Marijana Mišić Slobodan Sukdolak 《World journal of microbiology & biotechnology》2008,24(7):1239-1242
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. 相似文献
5.
Branislav Ranković Darko Ranković Marijana Kosanić Danijela Marić 《Central European Journal of Biology》2010,5(5):649-655
The aim of this study was to characterize the antioxidant and antimicrobial activity of the methanol extracts of: Anaptychya ciliaris, Nephroma parile, Ochrolechia tartarea and Parmelia centrifuga. The methanol extract of the P. centrifuga showed a strong antioxidant activity, in comparison to the extracts from A. ciliaris, O. tartarea and N. parile which were relatively weaker. Furthermore, the methanol extract of the lichen P. centrifuga was shown to contain the highest total phenol content (54.19 mg/g of the dry extract). Interestingly, a statistically significant
positive relationship between the antioxidant activity and the total phenol content was observed. The minimum inhibitory concentration
(MIC) against six bacterial and eleven fungi was established for the methanol extracts from each of species of lichens. The
methanol extracts of the lichens P. centrifuga and O. tartarea showed the strongest both antibacterial and antifungal activity. Taken together, the results from this study suggest that
the lichens P. centrifuga and O. tartarea may be used as a natural source of antioxidants in addition to providing certain antimicrobial features. 相似文献
6.
The work was conducted with the purpose to evaluate antioxidant activity of Parmelia saxatilis (PS) by different analytical methods. Water and methanol were used as solvents and antioxidative effects were measured by
a ferric thiocyanate method (FTC) and thiobarbituric acid test (TBA). The antioxidant activity increased with the increasing
amount of extracts (from 50 to 250 μg) added to linoleic acid emulsion. The methanol extract of PS exhibited high antioxidative
activity that was not significantly (P < 0.05) different from α-tocopherol, while aqueous extracts of PS showed low antioxidative activity. Similar trends of antioxidant activity were observed
using either the FTC or TBA methods. Antioxidant activity, reducing power, free radical scavenging (DPPH·), superoxide anion radical scavenging, metal chelating and hydrogen peroxide scavenging activities of PS extracts showed
dose dependence and increased with concentration of PS extract. The results obtained in the present study indicate that the
PS might be a potential source of natural antioxidant. 相似文献
7.
The susceptibility of Viridans streptococci to leaf extracts of Mangifera indica was studied on 53 clinical isolates from
39 patients. All the isolates were found to be susceptible to both water and methanol extract of M. indica leaves. Minimum inhibitory concentration (MIC) of methanol extract for all isolates were <50 mg/mL and MIC of water extract
for all isolates were <200 mg/mL. Methanol extract was found to have better action against Viridans streptococci than water
extract. 相似文献
8.
Chinnadurai Sreenath Kumar Dronamraju V. L. Sarada Thomas Paul Gideon Ramasamy Rengasamy 《World journal of microbiology & biotechnology》2008,24(9):1989-1992
The antibacterial properties of the three seagrasses namely Cymodocea serrulata, Halophila ovalis and Zostera capensis were tested against the human pathogens Staphylococcus aureus, Bacillus cereus, B. subtilis, Escherichia coli, Salmonella paratyphi, Salmonella typhimurium and Micrococcus luteus, using six different solvents namely, petroleum ether, chloroform, ethyl acetate, acetone, methanol and water. Ethyl acetate
and methanol extracts showed maximum activity against most of the pathogens when compared to other solvents. Experiments are
underway to isolate active compound(s) implicated in controlling the growth of the pathogens in vitro. 相似文献
9.
MA Nakisah MY Ida Muryany H Fatimah R Nor Fadilah MR Zalilawati S Khamsah M Habsah 《World journal of microbiology & biotechnology》2012,28(3):1237-1244
Crude methanol extracts of a marine sponge, Aaptos
aaptos, collected from three different localities namely Kapas, Perhentian and Redang Islands, Terengganu, Malaysia, were tested
in vitro on a pathogenic Acanthamoeba castellanii (IMR isolate) to examine their anti-amoebic potential. The examination of anti-Acanthamoebic activity of the extracts was
conducted in 24 well plates for 72 h at 30 °C. All extracts possessed anti-amoebic activity with their IC50 values ranging from 0.615 to 0.876 mg/mL. The effect of the methanol extracts on the surface morphology of A. castellanii was analysed under scanning electron microscopy. The ability of the extracts to disrupt the amoeba cell membrane was indicated
by extensive cell’s blebbing, changes in the surface morphology, reduced in cell size and with cystic appearance of extract-treated
Acanthamoeba. Number of acanthapodia and food cup was also reduced in this Acanthamoeba. Morphological criteria of apoptosis in Acanthamoeba following treatment with the sponge’s extracts was determined by acridine orange-propidium iodide staining and observed by
fluorescence microscopy. By this technique, apoptotic and necrotic cells can be visualized and quantified. The genotoxic potential
of the methanol extracts was performed by the alkaline comet assay. All methanol extracts used were significantly induced
DNA damage compared to untreated Acanthamoeba by having high percentage of scores 1, 2, and 3 of the DNA damage. Results from cytotoxicity and genotoxicity studies carried
out in the present study suggest that all methanol extracts of A. aaptos have anti-amoebic properties against A. castellanii. 相似文献
10.
The aim of the research is to explore the overall in vitro antioxidant activity, total phenol content, reduction power and
antimicrobial activity of the methanol extracts of the lichens Cetraria pinastri, Cladonia digitata, Cladonia fimbriata, Fulgensia fulgens, Ochrolechia parella and Parmelia crinita. The methanol extract of the Cetraria pinastri showed a strong antioxidant activity, whereas the extracts of the species Fulgenesi fulgens, Cladonia fimbriata and Parmelia crinita showed the moderate one and the extract of the species Ochrolechia parella and Cladonia digitata the weak one. The methanol extract of the lichen Cetraria pinastri had the biggest total phenol content (32.9 mg/g of the dry extract). A certain correlation was established between the antioxidant
activity and the total phenol content for the researched lichen extracts. The work also explores the antimicrobial activity
of the methanol extracts of the mentioned species of lichens against six bacterial and eleven fungi species by the disc-diffusion
method and by establishing the minimum inhibitory concentration (MIC). The methanol extracts of the lichens Cetraria pinastri and Parmelia crinita showed the strongest both antibacterial and antifungal activity against most of the tested microorganisms. These researches
suggest that the lichens Cetraria prunastri can be used as new sources of the natural antioxidants and the substances with antimicrobial features. 相似文献
11.
Various solvent extracts of the lichen Usnea ghattensis showed good antioxidant activity. A methanol extract prevented lipid peroxidation by 87% followed by 65% in Trolox at 20 μg/ml. It also showed superoxide anion scavenging activity and free radical scavenging activity 56% and 73%, respectively. The known antioxidants butylated hydroxytoluene (BHT), butylated hydroxyanisol (BHA) and quercetin at similar concentrations showed superoxide anion scavenging activity of 68, 59 and 47% and free radical scavenging activity 83, 77 and 69%, respectively. In addition, these extracts were inhibitory against Bacillus licheniformis, Bacillus megaterium, Bacillus subtilis and Staphylococcus aureus with MIC values of 5–10 μg/ml.Received after revisions 10 May 2005 相似文献
12.
Temperature response curves of chlorophyll a fluorescence parameters were used to assess minimum sub-zero temperature assuring functioning of photosynthetic photochemical
processes in photosystem II (PS II) of Antarctic lichens. Umbilicaria Antarctica and Xanthoria elegans were measured within the temperature range from −20 to +10°C by a fluorometric imaging system. For potential (F
V/F
M) and actual (Φ
II) quantum yields of photochemical processes the minimum temperature was found to be between −10 and −20°C. Non-photochemical
quenching (NPQ) of absorbed excitation energy increased with temperature drop reaching maximum NPQ at −15°C. Image analysis
revealed intrathalline heterogeneity of chlorophyll a fluorescence parameters with temperature drop. Temperature response of Φ
II exhibited an S-curve with pronounced intrathalline differences in X. elegans. The same relation was linear with only limited intrathalline difference in U. antarctica. The results showed that Antarctic lichen species were well adapted to sub-zero temperatures and capable of performing primary
photosynthesis at −15°C. 相似文献
13.
Michal Goga Heikki Pöykkö Wolfram Adlassnig Martin Bačkor 《Arthropod-Plant Interactions》2016,10(1):71-77
Lichens are characterized by a great variety of secondary metabolites. The function of these substances remains partly unknown. In this study, we propose that some of these metabolites may expel insect herbivores. To test this hypothesis, we reared larvae of the lichenivorous moth Cleorodes lichenaria on three selected lichens, Cladonia arbuscula subsp. mitis, Usnea hirta, and Usnea dasypoga. In experimental setup, the secondary metabolite usnic acid was removed from the lichens with acetone prior to feeding, whereas a control was left untreated. On all three lichens, removal of usnic acid from the lichens using acetone significantly prolonged survival of larvae and increased their viability. Larvae reared on control lichens contained significantly more usnic acid than those reared on treated lichens, both in their biomass and their faeces. These results support the hypothesis that usnic acid serves as a repellent against insect feeding, besides its well established functions of UV protection and antimicrobial properties. 相似文献
14.
Gordana Stojanović Igor Stojanović Vesna Stankov-Jovanović Violeta Mitić Danijela Kostić 《Central European Journal of Biology》2010,5(6):808-813
The methanol extracts of four Parmeliaceae lichens (Hypogymnia physodes, Evernia prunastri, Flavoparmelia caperata and Parmelia sulcata) were screened for antioxidant properties and total phenol content. The H. physodes extract was the most effective at reducing iron(III) and scavenging 1,1-diphenyl-2-picrylhydrazyl radicals, while the P. sulcata extract was the most effective in reducing molybdenum(VI) in an acidic medium. The E. prunastri and H. physodes extracts contained more Folin-Ciocalteu reagent reactive substances than the F. caperata and P. sulcata extracts. Significant activity of the H. physodes extract in DPPH and reducing Fe(III) assays suggest that this lichen can be considered as a potential source of antioxidants. 相似文献
15.
Simple method for fractionation of <Emphasis Type="Italic">Parmelia sulcata</Emphasis> lichen thalli
Three fractions were isolated from Parmelia sulcata lichen thalli: mycobiont-enriched fraction, highly purified preparation of Trebouxia sp. alga, and a photobiont-enriched fraction, in which the fungal component and symbiotic relations between the bionts were retained. The ratio between the fungal and algal components in all fractions was estimated from the photosynthesis/respiration and chlorophyll/dry weight ratios. Simple methods for lichen thallus fractionation are suggested to study symbiotic relationships of bionts.Translated from Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 306–310.Original Russian Text Copyright © 2005 by Maslov, Pavlova.This revised version was published online in April 2005 with a corrected cover date. 相似文献
16.
Milan S. Stanković Olgica Stefanović Ljiljana Čomić Marina Topuzović Ivana Radojević Slavica Solujić 《Central European Journal of Biology》2012,7(4):664-671
In vitro antimicrobial activity of 21 crude extracts obtained from seven taxa of the genus Teucrium (T. chamaedrys, T. montanum, T. arduini, T. polium, T. scordium subsp. scordium, T. scordium subsp. scordioides and T. botrys) was tested against bacterial and fungal species. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration
(MBC) were determined using a microdilution analysis method. Total phenolic content and flavonoid concentrations were measured
spectrophotometrically. Total phenols were determined using Folin-Ciocalteu reagent and their amounts ranged from 28.49 up
to 159.84 mg CA/g of extract (chlorogenic acid equivalent). The amounts of flavonoids ranged from 38.17 up to 190.45 mg RU/g
of extract (rutin equivalent).The plant extracts showed greater potential of antibacterial than antifungal activity. A relationship
was found between total phenolics and biological activity. The highest level of total phenols was measured in the methanol
extracts, which demonstrated higher antimicrobial activity than acetone and ethyl acetate extracts. Staphylococcus aureus ATCC 25923 appeared to be the most sensitive organism. Our results indicate that Teucrium spp extracts are rich sources of phenolic compounds and are promising candidates for further development as natural antimicrobial
agents. 相似文献
17.
Martin Pipíška Miroslav Horník L’uboš Vrtoch Jozef Augustín Juraj Lesný 《Biologia》2007,62(3):276-282
Cobalt is one of the possible contaminants originating from radioactive wastes or from metal mines and refineries. This paper
describes sorption of cobalt by the foliose lichen Hypogymnia physodes from CoCl2 solutions spiked with 60Co2+ in laboratory experiments. Maximum uptake was reached within 1 hour; the biosorption after 24 hours is not pH-dependent within
the range of pH 4–7, negligible at pH 2 and is not dependent on metabolic activity. The process can be described by the Freundlich
adsorption isotherm with ln k = 2.77, 1/n = 0.22 and R
2 = 0.94. Bivalent metal ions showed a concentration-dependent competitive effect on cobalt biosorption, decreasing in the
order: Cu > Ni > Ca > Mg. Monovalent ions, such as K+ and Na+, showed only very weak competitive effect. Up to 98% of Co taken up by lichen can be removed by washing with 0.1 M NiCl2 at 20°C. This means that only a small fraction of the cobalt is localized intracellularly. These results can be used for
elucidating the behaviour of lichens as bioindicators of cobalt pollution in water systems, including the risk of cobalt leakage
from lichen probes under the influence of rain, snow and atmospheric humidity. 相似文献
18.
A peptide antibiotic, gramicidin A, was covalently bound to cystamine self-assembled monolayers on gold surfaces. Each step
of the surface functionalization was characterized by polarization modulation infrared reflection absorption spectroscopy
and X-ray photoelectron spectroscopy. The antimicrobial activity of the anchored gramicidin was tested against three Gram-positive
bacteria (Listeria ivanovii, Enterococcus faecalis, and Staphylococcus aureus), the Gram-negative bacterium Escherichia coli and the yeast Candida albicans. The results revealed that the adsorbed gramicidin reduced, from 60% for E. coli to 90% for C. albicans, the number of culturable microorganisms attached to the surface. The activity was proven to be persistent overtime, up to
6 months after the first use. The bacteria attached to the functionalized surfaces were permeabilized as shown by confocal
microscopy. Taken together, these results indicate a bacteriostatic mode of action of the immobilized peptide. Finally, using
green fluorescent protein-expressing bacteria, it was shown that the development of a bacterial biofilm was delayed on peptide-grafted
surfaces for at least 24 h. 相似文献
19.
Jing Li Jianglin Zhao Lijian Xu Ligang Zhou Xiaolin Li Jingguo Wang 《World journal of microbiology & biotechnology》2008,24(5):733-737
About 63 fungal endophytic isolates were separated from rhizomes of Paris polyphylla var. yunnanensis, which is a traditional medicinal plant mainly distributed in China. The isolates were characterized and grouped based on
the culture characteristics and the morphology of colony growth and conidia. Eleven representative ones were selected for
further taxonomical identification. Five genera namely Fusarium, Gliocladiopsis, Gliomastix, Aspergillus and Cylindrocarpon were identified on the basis of their morphological characterizations. Of them, the most frequent genus was Fusarium (i.e. Ppf1, Ppf3 and Ppf14). Their ITS-rDNA sequences were compared with those available in the GeneBank databases to obtain
the closest related species by BLAST analysis as well as to analyze their phylogenetic affiliation. The isolates were identified
as Gliocladiopsis irregularis (Ppf2), Plectosphaerella cucumerina (Ppf4), Padospora sp. (Ppf6), Gliomastix murorum var. murorum (Ppf7), Aspergillus fumigatus (Ppf9), Pichia guilliermondii (Ppf10), Neonectria radicicola (anamorph: Cylindrocarpon) (Ppf12) and one uncultured mycorrhizal ascomycete (Ppf13) separately based on their morphological and molecular features.
The molecular characters of the endophytic fungi were basically coincident with their morphology. The broad diversity and
taxonomic spectrum were exhibited by the endophytic fungi from P. polyphylla var. yunnanensis. 相似文献
20.
In lichens, ribitol is known as a carbon storage compound, an osmotic agens involved effectively in cell compartments protection
during dehydration of lichen thalli and as a cryoprotective compound. In our study, we investigated the effect of ribitol
on photochemical processes of photosynthesis in foliose lichens [Lasallia pustulata (L.) Mérat., Umbilicaria hirsuta (Sw. ex Westr.) Hoffm.] at low temperature. The effects of three concentrations of ribitol, added externally to thalli segments
on several chlorophyll (Chl) fluorescence parameters, were evaluated. The 72 h exposition to 8, 16, and 26 mM ribitol led
to a concentration-dependent increase in FV/FM, decrease in non-photochemical quenching (NPQ) but no change in quantum yield of photosystem II photochemistry (ΦPSII) values at −5 °C). At higher temperature (0, +5 °C), no effect of ribitol addition on the photosynthetic parameters was apparent. 相似文献