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Punctelia Diffractaica
''Punctelia diffractaica'' is a species of foliose lichen in the family Parmeliaceae. It is found in Peru. Taxonomy The lichen was described as a species new to science by Japanese lichenologist Syo Kurokawa in 1999. The type was collected by colleague Hiroyuki Kashiwadani in the Saylla District ( Cuzco Province), where it was found in a pasture on the side of a road, growing on a calcareous rock at an altitude of about . It is named for its uncommon metabolite, diffractaic acid. Description The lichen has a foliose (leafy) thallus that is greenish-gray in colour, with a tight attachment to its substrate. It has a more or less rough, leathery texture, reaching dimensions of in diameter, comprising irregular lobes that are wide. Like all species of ''Punctelia'', ''P. diffractaica'' has minute pores – pseudocyphellae – that help facilitate gas exchange. The thallus surface features isidia that originate either from the pseudocyphellae, or directly from the surfa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Exchange
Gas exchange is the physical process by which gases move passively by diffusion across a surface. For example, this surface might be the air/water interface of a water body, the surface of a gas bubble in a liquid, a gas-permeable membrane, or a biological membrane that forms the boundary between an organism and its extracellular environment. Gases are constantly consumed and produced by cellular and metabolic reactions in most living things, so an efficient system for gas exchange between, ultimately, the interior of the cell(s) and the external environment is required. Small, particularly unicellular organisms, such as bacteria and protozoa, have a high surface-area to volume ratio. In these creatures the gas exchange membrane is typically the cell membrane. Some small multicellular organisms, such as flatworms, are also able to perform sufficient gas exchange across the skin or cuticle that surrounds their bodies. However, in most larger organisms, which have a small surface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichens Described In 1999
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not plants. They may have tiny, leafless branches ( fruticose); flat leaf-like structures ( foliose); grow crust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichen Species
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches ( fruticose); flat leaf-like structures ( [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioxidant
Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubricants, to prevent oxidation, and to foods to prevent spoilage, in particular the rancidification of oils and fats. In cells, antioxidants such as glutathione, mycothiol or bacillithiol, and enzyme systems like superoxide dismutase, can prevent damage from oxidative stress. The only dietary antioxidants are vitamins A, C, and E, but the term ''antioxidant'' has also been applied to numerous other dietary compounds that only have antioxidant properties in vitro, with little evidence for antioxidant properties in vivo. Dietary supplements marketed as antioxidants have not been shown to maintain health or prevent disease in humans. History As part of their adaptation from marine life, terrestrial plants began producing non-marine anti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Activity
In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or pharmacophore but can be modified by the other constituents. Among the various properties of chemical compounds, pharmacological/biological activity plays a crucial role since it suggests uses of the compounds in the medical applications. However, chemical compounds may show some adverse and toxic effects which may prevent their use in medical practice. Activity is generally dosage-dependent. Further, it is common to have effects ranging from beneficial to adverse for one substance when going from low to high doses. Activity depends critically on fulfillment of the ADME criteria. To be an effective drug, a compound not only must be active against a target, but also possess the appropriate ADME (Absorption, Distribution, Metabolism, and ... [...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 formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punctelia Punctilla
''Punctelia punctilla'' is a species of foliose lichen in the family Parmeliaceae. It is found in Africa, South America, and North America, where it grows on bark and on rocks. The main characteristics that distinguish ''Punctelia punctilla'' from other species of ''Punctelia'' are the presence of isidia on the thallus surface, a pale brown thallus undersurface, and the presence of lecanoric acid in the medulla. Taxonomy It was first formally described in 1977 as a new species by American lichenologist Mason Hale as ''Parmelia punctilla''. The type specimen was collected by Ove Almborn in the Cathedral Peak area of South Africa, where it was found growing on a rock in Indumeni forest. The altitude of the type locality was . Hildur Krog transferred it to the genus ''Punctelia'' in 1982. In 1997, Mónica Adler proposed to synonymize the taxon ''Punctelia missouriensis'' with ''P. punctilla''. André Aptroot later rejected this proposal, suggesting sufficient morp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology is a branch of biology dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance ( shape, structure, colour, pattern, size), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Metabolite
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atranorin
Atranorin is a chemical substance produced by some species of lichen. It is a secondary metabolite belonging to a group of compounds known as depsides. Atranorin has analgesic, anti-inflammatory, antibacterial, antifungal, cytotoxic, antioxidant, antiviral, and immunomodulatory properties. In rare cases, people can react allergic Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic derm ... to atranorin. References Further reading * * * * Polyphenols Lichen products {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apothecia
An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are most commonly bowl-shaped (apothecia) but may take on a spherical or flask-like form that has a pore opening to release spores (perithecia) or no opening (cleistothecia). Classification The ascocarp is classified according to its placement (in ways not fundamental to the basic taxonomy). It is called ''epigeous'' if it grows above ground, as with the morels, while underground ascocarps, such as truffles, are termed ''hypogeous''. The structure enclosing the hymenium is divided into the types described below (apothecium, cleistothecium, etc.) and this character ''is'' important for the taxonomic classification of the fungus. Apothecia can be relatively large and fleshy, whereas the others are microscopic—about the size of flecks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
