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Niebla (lichen)
''Niebla'' is a genus of yellow-green fruticose lichens that grow on rocks, trees, and shrubs within the fog zone of coastal North America,Brodo, I. M., S. D. Sharnoff, and S. Sharnoff. 2001. Lichens of North America. Yale University Press: New Haven. or more narrowly defined to occur on rocks and soil along the Pacific Coast from Mendocino County in California south to Baja California Sur.Spjut, R. W. 1996. ''Niebla'' and ''Vermilacinia'' (Ramalinaceae) from California and Baja California. Sida Miscellany 14, pp. 1-208. Botanical Research Institute of Texas, Inc., Fort Worth. Taxonomy The genus name is a substitute nameRundel, P.W. and P.A. Bowler, 1978. ''Niebla'', a new generic name for ''Desmazieria'' (Ramalinaceae). Mycotaxon 6: 497–499 for ''Desmazieria'', a homonym created by Camille Montagne in 1852 who recognized only one species in the genus (''D. homalea''); however, the name ''Desmazeria'', although not spelled exactly the same but nevertheless considered to be t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niebla Homalea
''Niebla homalea'' is a species of fruticose lichen that grows on rocks in foggy areas along the Pacific Coast of North America, from Mendocino County, California south to Bahía de San Quintín on the main peninsula of Baja California, with an isolated occurrence further south on vertical rock faces above Punta Camachos, and other occurrences in the Channel Islands and on Guadalupe Island.Spjut, R. W. 1996. ''Niebla'' and ''Vermilacinia'' (Ramalinaceae) from California and Baja California. Sida Bot. Misc. 14 The epithet ''homalea'', given by Acharius, suggests it was in regard to the branches appearing flattened. Distinguishing features ''Niebla homalea'' is recognized by the thallus divided into narrow subcylindric, mostly linear shaped branches that have a glossy cortex frequently cracked along transverse ridges and by the branch margins alternating 90° in their orientation at frequent but irregular intervals; the branches are 4–8 cm long, 1–3 mm wide. Apot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermilacinia
''Vermilacinia'', a genus of lichenized fungi in the family Ramalinaceae, is a yellow-green fruticose type of lichen with about 30 species that grow on rocks, trees, and soil within the fog zone along the Pacific Coast of North America and South America.Spjut, R. W. ''Niebla'' and ''Vermilacinia'' (Ramalinaceae) from California and Baja California. Sida Miscellany 14 The genus name refers to the thallus being divided into narrow worm-like (vermis) branches (lacinia);the latter part of the name (lacinia) generally applied in descriptions and taxonomic keys such as exemplified in a key to Sonoran Desert species of ''Ramalina''. The species of ''Vermilacinia'' are classified in two subgenera: subgenus ''Cylindricaria'' and subgenus ''Vermilacinia''. Subgenus ''Cylindricaria'', which includes 10+ species (type: ''Vermilacinia corrugata'' Spjut) that grow mostly on shrubs, is distinguished by a thin membranous pliable cortex (an outer skin-like layer composed of gelatinized hyphal ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depside
A depside is a type of polyphenolic compound composed of two or more monocyclic aromatic units linked by an ester bond. Depsides are most often found in lichens, but have also been isolated from higher plants, including species of the Ericaceae, Lamiaceae, Papaveraceae and Myrtaceae. Certain depsides have antibiotic, anti- HIV, antioxidant, and anti-proliferative activity ''in vitro''. As inhibitors of prostaglandin synthesis and leukotriene B4 biosynthesis, some depsides have ''in vitro'' anti-inflammatory activity. A depsidase is a type of enzyme that cuts depside bonds. One such enzyme is tannase. Examples Gyrophoric acid, found in the lichen '' Cryptothecia rubrocincta'', is a depside. Merochlorophaeic acid, isolated from lichens of the genus '' Cladonia'', is an inhibitor of prostaglandin synthesis. Some depsides are described as anti-HIV. See also *Salsalate homodimer formed from self-condensation of salicylic acid Salicylic acid is an organic compound with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Metabolites
Secondary metabolites, also called specialised metabolites, toxins, secondary products, or natural products, are organic compounds produced by any lifeform, e.g. bacteria, fungi, animals, or plants, which are not directly involved in the normal growth, development, or reproduction of the organism. Instead, they generally mediate ecological interactions, which may produce a selective advantage for the organism by increasing its survivability or fecundity. Specific secondary metabolites are often restricted to a narrow set of species within a phylogenetic group. Secondary metabolites often play an important role in plant defense against herbivory and other interspecies defenses. Humans use secondary metabolites as medicines, flavourings, pigments, and recreational drugs. The term secondary metabolite was first coined by Albrecht Kossel, a 1910 Nobel Prize laureate for medicine and physiology in 1910. 30 years later a Polish botanist Friedrich Czapek described secondary met ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thin-layer Chromatography
Thin-layer chromatography (TLC) is a chromatography technique used to separate non-volatile mixtures. Thin-layer chromatography is performed on a sheet of an inert substrate such as glass, plastic, or aluminium foil, which is coated with a thin layer of adsorbent material, usually silica gel, aluminium oxide (alumina), or cellulose. This layer of adsorbent is known as the stationary phase. After the sample has been applied on the plate, a solvent or solvent mixture (known as the mobile phase) is drawn up the plate via capillary action. Because different analytes ascend the TLC plate at different rates, separation is achieved. It may be performed on the analytical scale as a means of monitoring the progress of a reaction, or on the preparative scale to purify small amounts of a compound. TLC is an analytical tool widely used because of its simplicity, relative low cost, high sensitivity, and speed of separation. TLC functions on the same principle as all chromatography: a com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemotype
A chemotype (sometimes chemovar) is a chemically distinct entity in a plant or microorganism, with differences in the composition of the secondary metabolites. Minor genetic and epigenetic changes with little or no effect on morphology or anatomy may produce large changes in the chemical phenotype. Chemotypes are often defined by the most abundant chemical produced by that individual and the concept has been useful in work done by chemical ecologists and natural product chemists. With respect to plant biology, the term "chemotype" was first coined by Rolf Santesson and his son Johan in 1968, defined as, "...chemically characterized parts of a population of morphologically indistinguishable individuals."Keefover-Ring K, Thompson JD, and Linhart YB. 2009. Beyond six scents: defining a seventh ''Thymus vulgaris'' chemotype new to southern France by ethanol extraction. ''Flavour and Fragrance Journal'', 24(3): 117-122. doi:10.1002/ffj.1921 In microbiology, the term "chemoform" or "che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic groups are typically characterised by shared derived characteristics ( synapomorphies), which distinguish organisms in the clade from other organisms. An equivalent term is holophyly. The word "mono-phyly" means "one-tribe" in Greek. Monophyly is contrasted with paraphyly and polyphyly as shown in the second diagram. A ''paraphyletic group'' consists of all of the descendants of a common ancestor minus one or more monophyletic groups. A '' polyphyletic group'' is characterized by convergent features or habits of scientific interest (for example, night-active primates, fruit trees, aquatic insects). The features by which a polyphyletic group is differentiated from others are not inherited from a common ancestor. These definitions have tak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyletic
In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic group (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of Synapomorphy and apomorphy, synapomorphies and symplesiomorphy, symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term was coined by Willi Hennig to apply to well-known taxa like Reptilia (reptiles) which, as commonly named and traditionally defined, is paraphyletic with respect to mammals and birds. Reptilia contains the last common ancestor of reptiles a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Phylogenetics
Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to determine the processes by which diversity among species has been achieved. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree. Molecular phylogenetics is one aspect of molecular systematics, a broader term that also includes the use of molecular data in taxonomy and biogeography. Molecular phylogenetics and molecular evolution correlate. Molecular evolution is the process of selective changes (mutations) at a molecular level (genes, proteins, etc.) throughout various branches in the tree of life (evolution). Molecular phylogenetics makes inferences of the evolutionary relationships that arise due to molecular evolution and results in the construction of a phylogenetic tree. History The theoretical frame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salazinic Acid
Salazinic acid is a depsidone with a lactone ring. It is found in some lichens, and is especially prevalent in ''Parmotrema'' and ''Bulbothrix'', where its presence or absence is often used to help classify species in those genera. History In 1897, Friedrich Wilhelm Zopf named the chemical he originally isolated from the African species '' Stereocaulon salazinum'' as salazinic acid. Later studies showed that the compound he named was actually norstictic acid. In 1933, Yasuhiko Asahina and J. Asano studied salazinic acid they had isolated from '' Parmelia cetrata'', and found a unique ring system with seven members containing two phenolic components. The fundamental structure was named depsidone, that is, a seven-membered ring with an oxygen bridge binding two aromatic rings. Japanese chemists demonstrated in the late 1960s that the isolated mycobiont of the lichen '' Ramalina crassa'' could produce salazinic acid when grown in laboratory culture. Subsequent studies tried ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Pigment
Biological pigments, also known simply as pigments or biochromes, are substances produced by living organisms that have a color resulting from selective color absorption. Biological pigments include plant pigments and flower pigments. Many biological structures, such as skin, eyes, feathers, fur and hair contain pigments such as melanin in specialized cells called chromatophores. In some species, pigments accrue over very long periods during an individual's lifespan. Pigment color differs from structural color in that it is the same for all viewing angles, whereas structural color is the result of selective reflection or iridescence, usually because of multilayer structures. For example, butterfly wings typically contain structural color, although many butterflies have cells that contain pigment as well. Biological pigments See conjugated systems for electron bond chemistry that causes these molecules to have pigment. * Heme/porphyrin-based: chlorophyll, bilirubin, hemocy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
