OBJECTIVETo study the chemical constituents of the whole lichen of Usnea longissima.

METHODThe compounds were separated by silica gel, Sephadex LH-20 chromatography and high performance liquid chromatography (HPLC). The structures of the compounds isolated were identified by physico-chemical properties and spectral analysis.

RESULTTen compounds were isolated and their structures were identified as (4aR,9bS)-2,6-diactyl-3,4a,7,9-tetrahydroxy-8,9b-dimethyl-1-oxo-1,4,4a, 9b-tetrahydrodibenzo [b,d]furan (1), (+)-usnic acid (2), orcinol (3), 18R-hydroxydihydroalloprotolichensterinic acid (4), 5, 8-epidioxy-5alpha, 8alpha-ergosta-6, 22E-dien-3beta-ol (5), ethyl everninate (6), arabitol(7), apigenin 7-O-beta-D-glucuronide (8), 3-hydroxy-5-methoxy-2-methylbenzoic acid(9), friedelin(10).

CONCLUSIONCompound 1 was a new compound. Compound 8 was isolated from genu Usnea for the first time and compounds 3, 4 and 7 were isolated from U. longissima for the first time.

Medicine, Mongolian Traditional ; Usnea ; chemistry

OBJECTIVETo study the chemical constituents of Usnea longissima.

METHODThe compounds were isolated and purified by the methods of solvent extraction and chromatographic technique, and their structures were identified on the basis of the analysis of spectral data or comparison with those of authentic sample.

RESULTThirteen compounds were obtained and identified as ethyl hematommate (1), friedelin (2), beta-amyrin (3), beta-sitosterol (4), methyl-2,4-dihydroxy-3,6-dimethylbenzoate (5), barbatinic acid (6), zeorin (7), ethyl orsellinate (8), 3beta-hydroxy-glutin-5-ene (9), oleanolic acid (10), (+)-usnic acid (11), methylorsellinate (12), and 4-methyl-2,6-dihydroxy-benzaldehyde (13).

CONCLUSIONCompounds 2, 3, 5, and 8-10 were isolated from this genus for the first time, and compounds 1,4 were obtained from this plant for the first time.

Organic Chemicals ; analysis ; isolation & purification ; Usnea ; chemistry

Usnea Adans. is a somewhat rare lichen in South Korea, and, in nearly two decades, no detailed taxonomic or revisionary study has been conducted. This study was based on the specimens deposited in the lichen herbarium at the Korean Lichen Research Institute, and the samples were identified using information obtained from recent literature. In this study, a total of eight species of Usnea, including one new record, Usnea hakonensis Asahina, are documented. Detailed descriptions of each species with their morphological, anatomical, and chemical characteristics are provided. A key to all known Usnea species in South Korea is also presented.
Academies and Institutes ; Lichens* ; Republic of Korea ; Usnea*

OBJECTIVETo develop a RP-HPLC method for determining the contents of atranol, lecanorin, ethyl orsellinate and methyl orsellinate in Usnea diffracta.

METHODA Kromasil-C18 column (4.6 mm x 250 mm, 5 microm) was used at 25 degrees C with the mobile phases of acetonitrile -1% acetic acid in a gradient manner. The flow rate was set at 1.0 mL x min(-1). The detection wavelength was 280 nm.

RESULTThe correlation coefficients of atranol, lecanorin, ethyl orsellinate, and methyl orsellinate were higher than 0.999. Recoveries were from 102.9% to 95.30%; with RSD from 2.3% to 1.9%.

CONCLUSIONThe method is quick, simple and repeatable for simultaneous determination of atranol, lecanorin, ethyl orsellinate and methyl orsellinate in U. diffracta.

Benzaldehydes ; analysis ; Chromatography, High Pressure Liquid ; methods ; Resorcinols ; analysis ; Usnea ; chemistry

OBJECTIVETo study the chemical constituents of Usnea longissima.

METHODThe compounds were isolated and purified by the methods of solvent extraction and chromatographic technique, and their structures were identified on the basis of the analyses of spectral data.

RESULTTwo compounds were obtained and identified as 3, 6-diacetyl-2, 7, 9-trihydroxy-8, 9b-dimethyl-1 [9bH]-dibenzofuranone(1) and 1, 3, 8-trihydroxy4, 6-dimethyl-9, l0-anthracenedione(2), respectively.

CONCLUSIONCompounds 1 and 2 were new compounds and were named as longiusnine and longissimausnone, respectively.

Anthraquinones ; analysis ; chemistry ; isolation & purification ; Benzofurans ; analysis ; chemistry ; isolation & purification ; Magnetic Resonance Spectroscopy ; Usnea ; chemistry

Usnea longissima has a long history of use as a traditional medicine. Several bioactive compounds, primarily belonging to the polyketide family, have been isolated from U. longissima. However, the genes for the biosynthesis of these compounds are yet to be identified. In the present study, three different types of non-reducing polyketide synthases (UlPKS2, UlPKS4, and UlPKS6) were identified from a cultured lichen-forming fungus of U. longissima. Phylogenetic analysis of product template domains showed that UlPKS2 and UlPKS4 belong to group IV, which includes the non-reducing polyketide synthases with an methyltransferase (MeT) domain that are involved in methylorcinol-based compound synthesis; UlPKS6 was found to belong to group I, which includes the non-reducing polyketide synthases that synthesize single aromatic ring polyketides, such as orsellinic acid. Reverse transcriptase-PCR analysis demonstrated that UlPKS2 and UlPKS4 were upregulated by sucrose; UlPKS6 was downregulated by asparagine, glycine, and alanine.
Alanine ; Asparagine ; Fungi* ; Glycine ; Humans ; Medicine, Traditional ; Polyketide Synthases ; Polyketides ; Sucrose ; Usnea*

OBJECTIVETo summarize the studies on chemical constituents and pharmacological activities of lichens of Usnea genus.

METHODA systematic literature survey was conducted to classifiy and summarize chemical constituents of lichens of Usnea genus, and sum up current studies on main pharmacological activities of lichens of the genus.

RESULTLichens of Usnea genus contained multiple chemical constituents, primarily including mono-substituted phenyl rings, depsides, anthraquinones, dibenzofurans, steroids, terpenes, fatty acids and polysaccharides, with such biological activities as antitumor, antibacterial, anti-inflammation, anti-oxidation and antithrombosis.

CONCLUSIONThis essay provides reference for further studies and development of lichens of Usnea genus.

Animals ; Humans ; Medicine, Chinese Traditional ; methods ; Organic Chemicals ; chemistry ; pharmacology ; Usnea ; chemistry

A quick HPLC-ESI-MS/MS method was established for simultaneous determination of three chemical compositions in Usnea, including usnic acid, diffractaic acid, and ramalic acid. The separation was performed on a chromatographic column of Agilent ZORBAX SB-C, (4.6 mm x 250 mm, 5 µm), and the mobile phase was methanol (0.05% formic acid)-0.05% formic acid solution (4 mmol ammonium acetate), with an isocratic elution at a flow rate of 0.8 ml · min⁻¹. Multiple reaction monitoring scanning mode (MRM) was performed combined with the ion switching technology in positive and negative ion switching mode to apply for the quantitative determination. The calibration curves for the above three compounds were linear in corresponding injection amount. Their average recoveries were 95.0%-105.1%, with RSDs of 1.1%-5.2%. The method was simple, rapid, accurate with high repeatability, which could provide a reference for overcalling evaluation the quality of Usnea.
Chromatography, High Pressure Liquid ; methods ; Hydroxybenzoates ; analysis ; Spectrometry, Mass, Electrospray Ionization ; methods ; Tandem Mass Spectrometry ; methods ; Usnea ; chemistry