Antibacterial Activities of Ramalin, Usnic Acid and its Three Derivatives Isolated from the Antarctic Lichen Ramalina terebrata

Paudel, Bishnu Hari; Bhattarai, Hari Datta; Lee, Hong Kum; Oh, Hyuncheol; Shin, Hyun Woung; Yim, Joung Han

doi:10.1515/znc-2010-1-206

Cited by 43 publications

(20 citation statements)

References 16 publications

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“…(Hauck et al 2009). Some lichen compounds were shown to exhibit antibacterial (Motohashi et al 2010;Paudel et al 2010), cytostatic (Bogo et al 2010;Millot et al 2009;Tokiwano et al 2009), and antiviral activities (Esimone et al 2009). Indeed, major improvements in spectroscopy and systems biology have also stimulated renewed interest in the structural, metabolic and pharmaceutical analysis of lichen compounds.…”

Section: Lichen Chemistrymentioning

confidence: 99%

Advanced methods for the study of the chemistry and the metabolism of lichens

2011

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Lichens are compound entities of a fungal partner (''mycobiont'') and one or more photosynthetically active algae or cyanobacteria (''photobionts''). The organisms live in an intimate, symbiotic association which has been classified as a mutualistic or controlled parasitic relationship. Several metabolites from lichens display unique structures with unknown functions, and only a few model species have been analysed comprehensively. The complex metabolic interplay between the organisms in lichens is also incompletely understood. Earlier experiments with 14 C-labelled precursors indicated that the photobionts produce from CO 2 glucose or sugar alcohols (e.g. ribitol and arabitol) which are then transferred to the mycobionts. In the fungi, these compounds are believed to be converted into mannitol serving as the carbon and energy source in the downstream metabolic processes. Recent methodological developments in spectroscopy and ''systems biology'' now enable a concise analysis of the metabolite profiles, networks and fluxes by non-targeted quantitative approaches. In this review, we summarize the current knowledge about lichen metabolism and report on the potential of the advanced methods to reinvestigate lichen chemistry and metabolism on a quantitative basis.

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Section: Lichen Chemistrymentioning

confidence: 99%

Advanced methods for the study of the chemistry and the metabolism of lichens

2011

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“…Furthermore, Yilmaz et al (24) showed that usnic acid with quite low MIC values (0.15 g per disk) was effective against 10 7 cells/ml of Candida albicans or Candida glabrata. Similarly, lower MICs (ranging from 1 to 26 g/ml) determined by the disk diffusion method have been observed against Bacillus subtilis (18). One factor that may explain our results include the absence of standardized anticandidal assays for natural products.…”

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confidence: 51%

Effect of Usnic Acid on Candida orthopsilosis and C. parapsilosis

Pires

Lucarini

Mendes-Giannini

2012

Antimicrob Agents Chemother

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The activity of usnic acid against Candida orthopsilosis and Candida parapsilosis on planktonic and biofilm conditions was investigated by using a broth microdilution and microplate methods. Potent in vitro activities against different Candida species were obtained. The metabolic activity of sessile cells of C. parapsilosis complex was reduced by 80% at four times the 80% inhibitory concentration. The in vitro studies support further efforts to determine whether usnic acid can be used clinically to cure patients with Candida infections.A mong the Candida strains reported to cause human diseases, more than 17 different species have been identified (9,19). Many of these species have been observed to occur in the hemodialysis setting and/or to exhibit innate or acquired resistance to one or more established antifungal agents (4,12,13,16,21). In addition, the use of molecular identification methods has resulted in the identification of new species within larger species complex such as Candida orthopsilosis and Candida metapsilosis within the Candida parapsilosis complex (23). In particular, the percentage of isolates of C. orthopsilosis has been much higher in the C. parapsilosis complex isolates in Latin America (12.7%) (11).The small number of drugs available for fungal treatment encourages the search for new chemotherapeutic agents. Usnic acid (2,6-diacetyl-1,2,3,9b-tetrahydro-7,9-dihydroxy-8,9b-dimethyldibenzofuran-1,3-dione), a secondary lichen metabolite, is known to possesses antimicrobial properties in addition to antiviral, antiprotozoal, antiproliferative, anti-inflammatory, and analgesic activity (10).With respect to antimicrobial properties, usnic acid has activity against a number of planktonic Gram-positive bacteria and also has the capacity to control biofilm formation by Staphylococcus aureus and Pseudomonas aeruginosa (8). Indeed, the mechanism of action expressed by usnic acid is still unknown. According to the same study (8), usnic acid could inhibit quorum sensing in P. aeruginosa biofilms.Usnic acid has been tested against some Candida species, but there is no published data concerning its activity against the newly described species within the C. parapsilosis complex. Thus, we tested usnic acid in both planktonic or biofilm modes of growth in C. orthopsilosis and C. parapsilosis.Six isolates of C. parapsilosis complex able to form biofilms were collected from a hemodialysis unit located in the state of São Paulo, Brazil, between March 2006 and March 2007 obtained from 110 samples of water that were selected for testing. The identification of C. parapsilosis and C. orthopsilosis was confirmed by molecular methods as described previously (23). The MIC for usnic acid of planktonic C. parapsilosis complex cultures was determined in RPMI 1640 buffered with morpholinepropanesulfonic acid (MOPS) (both from Sigma Chemical Co., St. Louis, MO) using a broth microdilution method adapted from the CLSI approved standard (M27-A3) (6). Briefly, the usnic acid (Sigma) was dissolved in 5% (vol/vol) in dimethyl ...

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“…A total of five compounds, usnic acid, usimine A, usimine B, usimine C, and ramalin, were isolated by bioactivity-guided fractionation of the methanol extract of Ramalina terebrata (Paudel et al 2010). The qualitative antibacterial activities of the isolated compounds were determined by the disk diffusion method, while the minimum inhibitory concentration (MIC) determination assay gave the quantitative strength of the test samples.…”

Section: Studies On Antimicrobial Activities Of Lichen Secondary Metamentioning

confidence: 99%

Lichen Secondary Metabolites

Ranković¹

2015

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Antibacterial Activities of Ramalin, Usnic Acid and its Three Derivatives Isolated from the Antarctic Lichen Ramalina terebrata

Cited by 43 publications

References 16 publications

Advanced methods for the study of the chemistry and the metabolism of lichens

Advanced methods for the study of the chemistry and the metabolism of lichens

Effect of Usnic Acid on Candida orthopsilosis and C. parapsilosis

Lichen Secondary Metabolites

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