Determination of Usnic Acid in Some Rhizoplaca Species from Middle Anatolia and their Antimicrobial Activities

Abstract

Three species of lichens, Rhizoplaca chrysoleuca (Sm.) Zopf, Rhizoplaca melanopthalma (DC.) Leuckert & Poelt and Rhizoplaca peltata Ramonds Leuckert, were collected from middle Anatolia, Erciyes Mountain (Kayseri) in Turkey. Their usnic acid amounts were determined by HPLC in acetone extracts. In addition, antimicrobial activities of these extracts were determined against Escherichia coli (ATCC 35218), Enterococcus faecalis (RSKK 508), Proteus mirabilis (Pasteur Ens. 235), Staphylococcus aureus, Bacillus subtilis, Bacillus megaterium and Pseudomonas aeruginosa. It was shown that, as the usnic acid amount increased, the antimicrobial activities increased too. The usnic acid contents of Rhizoplaca species varied between 0.19-4.0% dry weight

Mutagenic and antimutagenic properties of some lichen species grown in the Eastern Anatolia Region of Turkey

“…They produce a variety of metabolites. Several lichen extracts and their compounds have been used in traditional medicine in many places around the world [5,[8][9][10][11]. Until now chemical composition and some biological (antimicrobial and antioxidant) activities of the extracts of lichens grow in eastern part of Turkey have been reported [12,13].…”

Antimicrobial activity of usnic acid on Squamarina lentigera (Lichenized Ascomycetes) lichen species

“…Compared with the antimicrobial activity of R. chrysoleuca (21), which shows the highest inhibition effects on B. megatarium, the inhibition zones of S. lentigera was less, those of B. megatarium was found to be more sensitive to R. chrysoleuca extracts.…”

“…In our laboratory, several studies were accomplished on the antimicrobial activity of lichens collected from Turkey (16)(17)(18)(19)(20)(21)(22) (Figure 3). Comparing with the the present study, the usnic acid amounts of S. lentigera is found as 2.47% ( Figure 3).…”

Characterization of Sunflower Oil Extracts from the Lichen Usnea barbata

“…It should also be noted that the purity of UA seems to be higher in the sunflower oil extract when comparing the high-field regions (>9 ppm) of the NMR spectra (compare Figure 2 D,E). These findings probably reflect that the yield of UA is correlated with the solubility of this compound in the solvent used for extraction [ 38 , 57 , 58 ], the temperature, and the time assigned to the operation [ 34 ]. However, the UA content in extracted lichens certainly also depends on additional more complex parameters including the geographical origin of the lichen and the time of sampling.…”