Ramalina usnea

C,2H220,i 342.299 Constit. of the lichen polysaccharide in Cetraria islandica (iceland moss), Ramalina usnea and in the seed galacto-mannan of Cassia marylandica. 

Certain tissues of fruticose lichens, such as Ramalina Usnea, and Evernia, often extend deep into the corky bark tissue by growing between the periderm layers with hapteral wedgelike action. Studies of Rawa/ma species by Porter (1917) showed that these lichens gain entrance to the inner bark... 

Usnic Acid. 2I6 Diacetyl 7t9-dihydraxy 8i9b-di-methyl-It3(2H,9bH)-dibenzofurandione usninic acid usnein Usniacin. C H,407 mol wt 344.31. C 62.79%. H 4.68%, O 32.53%. Antibacterial substance found in lichens. Isolation from varieties of Usnea barbota (L.) Wigg., Usneaceae Rochleder, Heidi> Ann. 48, If (1843) Widman Ann. 310, 230 (1900) 324, 139 (1902). Isoin from Ramalina reticulata Marshak, Public Health Reports 62, 3 (1947) Stark et of., J. Am. Chem. Soc. 72, 1819 (1950). Occurs in nature in both the d- and /-forms as well as a racemic mixture. Structure Curd, Robertson, J. Chem. Soc. 1937, 894 Schopf, Ross, Ann. 546, (1941) Barton, Brunn, /. Chem. Soc. 1953, 603. Resolution of ( )-usnic acid Dean et ai, ibid. 1250. Synthesis Barton et a/., ibid. 1956, 530. Biosynthesis in vitro Penttila, FaJes, Chem. Commun 1966, 656. Abs config of (+)-fomv S. Huneck et aL, Tetrahedron Letters 22, 351 (1981). 

Ramalina siliquosa, R. subfarinacea Peltigera canina, Umbilicaria cylindrica, U. pustulata, Cladonia gr. pyxidata, Usnea muricata, H. physodes, Pseudevernia furfuracea, Parmelia conspersa, Bryoria fuscescens Hypogymnia caperata, Diploica canescens, Lecanora expallens H. physodes... 

The fluorescence parameter Fy/Fm was shown by Branquinho et al. (1997b) to have an additional use in the observation of the sensitivity of lichens to the uptake of Cu. Usnea spp. were found to be the most sensitive to Cu uptake as shown by fluorescence studies a total inhibition of PSII photochemical reactions occurred in Ramalina fastigiata when intercellular Cu concentrations exceeded a threshold of ca. 4.0 p,mol g , whereas an intracellular Cu concentration in Usnea spp. was already above this apparent threshold (ca. 4.0 p,mol g ) even for the lowest Cu concentration supplied, hence Fv/Fm was equal to zero for all Cu concentrations supplied. 

Wright J, Drtina GJ, Roberts RA, Paquette LA (1988) A cohvergent synthesis of triquinane sesterterpenes. Enantioselective synthesis of (-)-retigeranic acid A. J Am Chem Soc 110 5806-5817 Yamamoto Y (1985) Tissue cultures of Usnea rubescens and Ramalina yasudae and production of usnic acid in their cultures. Agric Biol Chem 49 3347-3348... 

It was first isolated by German scientist W. Knop in 1844 and first synthesised between 1933 and 1937 by Curd and Robertson. Usnic acid was identified in many genera of lichens including Usnea, Cladonia, Lecanora, Ramalina, Evernia, Parmelia and Alectoria. 

Pseudevernia, Parmeliaceae Pseudocyphellaria, Lobariaceae Punctelia, Parmelioid Ramalina, Ramalinaceae Rhizoplaca, Lecanoraceae Roccella, Roccellaceae Siphula, Icmadophilaceae Stereocaulon, Stereocaulonaceae Sticta, Lobariaceae Sulcaria, Alectorioid Teloschistes, Teloschistaceae Thamnolia, Icmadophilaceae Umbilicaria, Umbilicariaceae Usnea, Alectorioid Vulpicida, Cetrarioid Xanthoparmelia, Parmelioid Xanthoria, Teloschistaceae... 

An important dmg in many old Ayurvedic texts that is still used today. The first record is in the Atharvaveda (1500 B.E.). Although in some areas of India, high-quality chhariia is mostly Parmotrema nilgherrense, the lichen mixture can also contain Parmotrema chinense, P. perforatum, P. perlatum, Everniastrum cirrhatum, and E. nepalense, with the occasional adulterants Ramalina farinacea, R. infiata, Usnea baileyi,... 

Tripolitania (Libya) sciba Ingredient in medicinal decoction called sciba bom early 1900s, along with Usnea plicata, Ramalina calicaris, and R. farinacea (Natale and Pollio 2012)... 

Sisodia et al. (2013) evaluated antioxidant activity for different extract of Ramalina roesleri species and found that the DPPH radical scavenging activity of extracts ranged from 29.42 to 87.90 %. Sharma et al. (2012) examined the antioxidant activity of two common hchens, namely, Parmotrema reticulatum and Usnea... 

Tiirkez H, Aydin E, Aslan A (2012c) Effects of lichenic extracts (Hypogymnia physodes, Ramalina polymorpha and Usnea florida) on human blood cells cytogenetic and biochemical study. Iran J Pharm Res ll(3) 889-896. 

In some fruticose lichens, such as Usnea which has a radial arrangement of the tissues, a central axial strand can be distinguished internal to the medulla (Fig. 46). The structure of the central axis is dense and consists of paraplectenchymatous or prosoplectenchymatous tissue giving considerable tensile or skeletal strength to the thallus. In other genera, i.e., Alectoria, Cladonia, and Ramalina, the central axis is absent. Its place can be taken by a central hollow or by gelatinous or spongy tissues. In Letharia a central cord is formed by fusion of several smaller strands (Fig. 29). 

The lobes of fruticose lichens are strap-shaped or threadlike with a radial or dorsiventral thallus. Ramalina (Fig. 70) and Roccella (Fig. 79) are good examples of strap-shaped, radial thalli, while Usnea (Fig. 75) consists of thin strands up to 5 m long. Evernia and Pseudevernia have strap-shaped, dorsiventral thalli. 

Anatomical characters of thallus structure play a large role in the delimitation of foliose and fruticose genera. The constancy of axil formation of different types Usnea, Alectoria, Letharia, and Anzia), veins (Peltigera, Hydrothyria), supporting tissues (Ramalina), and ground structure of cortical formations (hyphae anticlinal versus periclinal, in Physco-nia versus Anaptychia, Physcia versus Heterodermia etc.) have frequently been confirmed. They are valid systematic criteria and will not be discussed further here. 

Lamb, I. M. (1964). Antarctic lichens. I. The genera Usnea, Ramalina, Himantormia, Alectoria, Cornicularia. Brit. Antarctic Surv. Sci. Rep. 38. 

Ramalina maciformis Parmelia melanothrix Parmelia tinctorum Usnea pseudocyphellata Cladonia alcicornis Stereocaulon alpinum Letharia vulpina Xanthoria mawsoni Neuropogon acromelanus Lecanora melanophthalma... 

Frost injury of lichens in their natural habitats has been rarely reported (Barkman, 1958) but this does not exclude its occurrence. After a severe winter (1962) in southeastern England, Laundon (1966) found thalli of Parmelia caperata totally bleached or discolored in the marginal zone. This must be exclusively due to winter killing and not to toxic damage because Ramalina farinacea and Usnea sp. growing in the same place were unharmed. Two years later the recovery of the lichen colony was observed. 

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