Lichens are symbiotic organisms which produce distinct secondary metabolic products. In the present study, we tested the cytotoxic activity of 17 lichen species against several human cancer cells and further investigated the molecular mechanisms underlying their anti-cancer activity. We found that among 17 lichens species, F. cucullata exhibited the most potent cytotoxicity in several human cancer cells. High performance liquid chromatography analysis revealed that the acetone extract of F. cucullata contains usnic acid, salazinic acid, Squamatic acid, Baeomycesic acid, d-protolichesterinic acid, and lichesterinic acid as subcomponents. MTT assay showed that cancer cell lines were more vulnerable to the cytotoxic effects of the extract than non-cancer cell lines. Furthermore, among the identified subcomponents, usnic acid treatment had a similar cytotoxic effect on cancer cell lines but with lower potency than the extract. At a lethal dose, treatment with the extract or with usnic acid greatly increased the apoptotic cell population and specifically activated the apoptotic signaling pathway; however, using sub-lethal doses, extract and usnic acid treatment decreased cancer cell motility and inhibited in vitro and in vivo tumorigenic potentials. In these cells, we observed significantly reduced levels of epithelial-mesenchymal transition (EMT) markers and phosphor-Akt, while phosphor-c-Jun and phosphor-ERK1/2 levels were only marginally affected. Overall, the anti-cancer activity of the extract is more potent than that of usnic acid alone. Taken together, F. cucullata and its subcomponent, usnic acid together with additional component, exert anti-cancer effects on human cancer cells through the induction of apoptosis and the inhibition of EMT.

Lichens are symbiotic organisms that produce various unique chemicals that can be used for pharmaceutical purposes. With the aim of screening new anti-cancer agents that inhibit cancer cell motility, we tested the inhibitory activity of seven lichen species collected from the Romanian Carpathian Mountains against migration and invasion of human lung cancer cells and further investigated the molecular mechanisms underlying their anti-metastatic activity. Among them, Alectoria samentosa, Flavocetraria nivalis, Alectoria ochroleuca, and Usnea florida showed significant inhibitory activity against motility of human lung cancer cells. HPLC results showed that usnic acid is the main compound in these lichens, and (+)-usnic acid showed similar inhibitory activity that crude extract have. Mechanistically, β-catenin-mediated TOPFLASH activity and KITENIN-mediated AP-1 activity were decreased by (+)-usnic acid treatment in a dose-dependent manner. The quantitative real-time PCR data showed that (+)-usnic acid decreased the mRNA level of CD44, Cyclin D1 and c-myc, which are the downstream target genes of both β-catenin/LEF and c-jun/AP-1. Also, Rac1 and RhoA activities were decreased by treatment with (+)-usnic acid. Interestingly, higher inhibitory activity for cell invasion was observed when cells were treated with (+)-usnic acid and cetuximab. These results implied that (+)-usnic acid might have potential activity in inhibition of cancer cell metastasis, and (+)-usnic acid could be used for anti-cancer therapy with a distinct mechanisms of action.

The current study describes seven species that are new to the lichen mycota of South Korea. A taxonomic description of Arthonia excipienda, A. radiata, Arthothelium ruanum, Enterographa leucolyta, Fissurina elaiocarpa, Rinodina oleae, and Thelotrema porinaceum was given and supported by distribution, ecology, and illustrations. Each species was compared with a species showing close resemblance.

This study presents the results obtained from qualitative and quantitative analysis of gallic acid from hydro-alcoholic extracts (methanol, ethanol) of plants from Plantae regnum. Plant qualitative analysis was performed using a novel mass spectrometric (MS) method based on fully automated chip-nanoelectrospray ionization (nanoESI) high capacity ion trap (HCT) while quantitative analysis was carried out by high performance liquid chromatography (HPLC). These methods were applied to Alchemilla vulgaris -common lady's-mantle (aerial part), Allium ursinum -bear's garlic (leaves), Acorus calamus -common sweet flag (roots), Solidago virga-aurea -goldenrod (aerial part). Obtained results indicated that methanol extracts (96%, 80%) have a gallic acid content ranging between 0.0011 -0.0576 mg mL -1 extract while the ethanol extracts (96%, 60%) exhibit a gallic acid concentration that varies between 0.0010 -0.0182 mg mL -1 extract. © Versita Sp. z o.o.

Nine phanerogam plants (common lady's-mantle, bear's garlic, common sweet flag, agrimony, goldenrod, common speedwell, european mistletoe, horsetail and milfoil) were evaluated regarding their total flavonoid contents and antioxidant activity. The flavonoid contents ranged from 0.72 (goldenrod) to 0.25 mmol/g dry matter (horsetail). The contents of quercetin, rutin, kaempferol and myricetin were quantified by high performance liquid chromatography. Quercetin content was found to be very low in goldenrod and mistletoe extracts (0.20 µmol/g dry matter in european mistletoe) and almost undetectable in the other seven extracts. The rutin content was much higher, ranging from 96.25 (goldenrod) to 0.49 µmol/g dry matter (common sweet flag). Except for horsetail, kaempferol was found in all other eight extracts, the biggest quantity (2.15 µmol/g dry matter) being in the goldenrod extract. Myricetin was only found in goldenrod and agrimony (0.35 and 0.08 µmol/ g dry matter respectively). Goldenrod and milfoil showed the highest values for the antioxidant activity, expressed as mol quercetin equivalent, in the DPPH · (1,1-diphenyl-2-picrylhydrazyl) method, namely 0.00542 and 0.00532. These results suggest them to be used as natural sources of antioxidants instead of synthetic ones. et al. 2004et al. , Hae et al. 2001.Flavones are a part of the naturally antioxidants that acts against the above mentioned radicals and also against the extremely reactive NO• and NO 2 • radicals. As antioxidants, they prevent vitamin C oxidation by copper enzymes being also synergetic with the ascorbic acid (Safta 2002). From structural point of view, flavones are a class of flavonoids based on the backbone of 2-phenylchromen-4-one (2-phenyl-1-benzopyran-4-one) (Szabo et al. 2007a). Common lady's-mantle, bear's garlic, common sweet flag, agrimony, goldenrod, common speedwell, european mistletoe, horsetail and milfoil are natural flavones resources. Except of bear's garlic, goldenrod, agrimony, common speedwell and European mistletoe that are characteristic to the Central European area, the rest of them are spread all over the world (Popovici et al. 1992). Their antioxidative and health effect is manifested whether consumed as herbal teas or food supplements. Ethanol macerates of these plants contains most of their active compounds and, additionally, are having good miscibility and long shelf life compared with other types of extracts like essential oils (Banu 2000). Plus, thermal treatment, that might alter their radical-scavenging activity (Khatun et al. 2006), is not needed. Determining their antioxidant activity is one of the steps to their conditioning, in order to be used as natural alternatives to the synthetic antioxidants in foods and food supplements. Experimental PartExtracts obtaining Five grams of vegetal material dried and grinded was submitted to static extraction (maceration) in 50 mL of 96% ethanol, for 10 days, at room temperature, under stirring 3-4 times/day, at dark. The obtained solutions were then filtered through 4 la...