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Lichen Products
Lichen products, also known as lichen substances, are organic compounds produced by a lichen. Specifically, they are secondary metabolites. Lichen products are represented in several different chemical classes, including terpenoids, orcinol derivatives, chromones, xanthones, depsides, and depsidones. Over 800 lichen products of known chemical structure have been reported in the scientific literature, and most of these compounds are exclusively found in lichens. Examples of lichen products include usnic acid (a dibenzofuran), atranorin (a depside), lichexanthone (a xanthone), salazinic acid (a depsidone), and isolichenan, an α-glucan. Many lichen products have biological activity, and research into these effects is ongoing. Biosynthesis Most lichen products are biochemically synthesized via the acetyl-polymalonyl pathway (also known as polyketide pathway), while only a few originate from the mevalonate and shikimate biosynthetic pathways. Occurrence Lichen products accumulate ...
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Lungwort (4504575158)
''Pulmonaria'' (lungwort) is a genus of flowering plants in the family Boraginaceae, native to Europe and western Asia, with one species (''P. mollissima'') east to central Asia. According to various estimates there may be between 10 and 18 species found in the wild. Description Lungworts are evergreen or herbaceous perennials that form clumps or rosettes. They are covered in hairs of varied length and stiffness, and sometimes also bear glands. The underground parts consist of a slowly creeping rhizome with adventitious roots. Flowering stems are unbranched, rough, covered with bristly hairs, usually not exceeding , with a few exceptions ('' P. mollis'', '' P. vallarsae''). The stems are usually upright, or slightly spreading. The plants reach in height, spreading up to wide. The leaves are arranged in rosettes. The blades are usually large, from narrowly lanceolate to oval, with the base ranging from heart shaped to very gradually narrowing, and can have a sharply pointe ...
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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. Biological activity is usually measured by a bioassay and the activity is generally dosage-dependent, which is investigated via dose-response curves. 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 ...
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Cetraria Islandica
''Cetraria islandica'', also known as true Iceland lichen or Iceland moss, is an Arctic-alpine lichen whose erect or upright, leaflike habit gives it the appearance of a moss, where its name likely comes from. Description It is often of a pale chestnut color, but varies considerably, being sometimes almost entirely grayish-white; and grows to a height of from , the branches being channeled into flattened lobes with fringed edges. Chemistry In commerce it is a light-gray harsh cartilaginous body, almost colorless, and tastes slightly bitter. It contains about 70% of lichenin or lichen-starch, a polymeric carbohydrate compound isomeric with common starch. It also yields a peculiar modification of chlorophyll (called ''thallochlor''), fumaric acid, lichenostearic acid, and cetraric acid (which gives it the bitter taste). It also contains lichesterinic acid and protolichesterinic acids. Distribution and habitat It grows abundantly in the mountainous regions of northern cou ...
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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 have an allergic reaction Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include Allergic rhinitis, hay fever, Food allergy, food al ... to atranorin. References Further reading * * * * Polyphenols Lichen products {{organic-compound-stub ...
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Thin-layer Chromatography
Thin-layer chromatography (TLC) is a chromatography technique that separates components in non-volatile mixtures. It is performed on a TLC plate made up of a non-reactive solid coated with a thin layer of adsorbent material. This is called the stationary phase. The sample is deposited on the plate, which is eluted with a solvent or solvent mixture known as the mobile phase (or eluent). This solvent then moves up the plate via capillary action. As with all chromatography, some compounds are more attracted to the mobile phase, while others are more attracted to the stationary phase. Therefore, different compounds move up the TLC plate at different speeds and become separated. To visualize colourless compounds, the plate is viewed under UV light or is stained.Jork, H., Funk, W., Fischer, W., Wimmer, H. (1990): Thin-Layer Chromatography: Reagents and Detection Methods, Volume 1a, VCH, Weinheim, Testing different stationary and mobile phases is often necessary to obtain well-defined an ...
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Analytical Chemistry
Analytical skill, Analytical chemistry studies and uses instruments and methods to Separation process, separate, identify, and Quantification (science), quantify matter. In practice, separation, identification or quantification may constitute the entire analysis or be combined with another method. Separation isolates analytes. Qualitative inorganic analysis, Qualitative analysis identifies analytes, while Quantitative analysis (chemistry), quantitative analysis determines the numerical amount or concentration. Analytical chemistry consists of classical, wet chemistry, wet chemical methods and modern analytical techniques. Classical qualitative methods use separations such as Precipitation (chemistry), precipitation, Extraction (chemistry), extraction, and distillation. Identification may be based on differences in color, odor, melting point, boiling point, solubility, radioactivity or reactivity. Classical quantitative analysis uses mass or volume changes to quantify amount. Ins ...
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Friedrich Wilhelm Zopf
Friedrich (or Friederich) Wilhelm Zopf (12 December 1846 – 24 June 1909) was a well-known German botanist and mycologist. He dedicated to his whole life with fungal biology, particularly in classification of fungi and dye production in fungi and lichens. Besides, his textbook on fungi called “Die pilze in morphologischer, physiologischer, biologischer und systematischer beziehung (Translation: The mushrooms in morphological, physiological, biological and systematic relationship)” in 1890 was also an outstanding work on the subject for many decades. The unicellular achlorophic microalgae ''Prototheca zopfii'' is named after him because of his profound suggestions and contributions to Krüger's pioneering work in ''Prototheca''. Thus, his numerous contributions gave him a special status in mycological history. Early life Wilhelm Zopf was born in Roßleben in Thuringia in 1846. Before going into biological science area, he has been an elementary school teacher in Thondorf at ...
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Cortex (botany)
In botany, a cortex is an outer layer of a stem or root in a vascular plant, lying below the epidermis but outside of the vascular bundles. The cortex is composed mostly of large thin-walled parenchyma cells of the ground tissue system and shows little to no structural differentiation. The outer cortical cells often acquire irregularly thickened cell walls, and are called collenchyma cells. Plants Stems and branches In the three dimensional structure of herbaceous stems, the epidermis, cortex and vascular cambium form concentric cylinders around the inner cylindrical core of pith. Some of the outer cortical cells may contain chloroplasts, giving them a green color. They can therefore produce simple carbohydrates through photosynthesis. In woody plants, the cortex is located between the periderm (bark) and the vascular tissue ( phloem, in particular). It is responsible for the transportation of materials into the central cylinder of the root through diffusion and ma ...
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Medulla (lichenology)
The medulla is a horizontal layer within a lichen thallus. It is a loosely arranged layer of interlaced hyphae below the upper cortex and photobiont A lichen ( , ) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualistic relationship.
zone, but above the lower cortex.Galloway, D.J. (1992). Flora of Australia - ''Lichen Glossary'' The medulla generally has a cottony appearance. It is the widest layer of a heteromerous lichen thallus.


References

Fungal morphology and anatomy Lichenology {{lichen-stub ...
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Dry Weight
Vehicle weight is a measurement of wheeled motor vehicles; either an actual measured weight of the vehicle under defined conditions or a gross weight rating for its weight carrying capacity. Curb or kerb weight Curb weight (American English) or kerb weight (British English) is the total mass of a vehicle with standard equipment and all necessary operating consumables such as motor oil, transmission oil, brake fluid, coolant, air conditioning refrigerant, and sometimes a full tank of fuel, while not loaded with either passengers or cargo. The gross vehicle weight is larger and includes the maximum payload of passengers and cargo. This definition may differ from definitions used by governmental regulatory agencies or other organizations. For example, many European Union manufacturers include the weight of a driver and luggage to follow EU Directive 95/48/EC. Organizations may also define curb weight with fixed levels of fuel and other variables to equalize the value for the compa ...
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Herbarium
A herbarium (plural: herbaria) is a collection of preserved plant biological specimen, specimens and associated data used for scientific study. The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sheet of paper (called ''exsiccatum'', plur. ''exsiccata'') but, depending upon the material, may also be stored in boxes or kept in alcohol or other preservative. The specimens in a herbarium are often used as reference material in describing plant taxon, taxa. Some specimens may be Type (botany), types, some may be specimens distributed in published series called exsiccata, exsiccatae. The term herbarium is often used in mycology to describe an equivalent collection of preserved fungi, otherwise known as a fungarium. A xylarium is a herbarium specialising in specimens of wood. The term hortorium (as in the Liberty Hyde Bailey, Liberty Hyde Bailey Hortorium) has occasionally been applied to a herbarium specialising in preserving material of ...
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Scanning Electron Microscopy
A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the surface topography and composition. The electron beam is scanned in a raster scan pattern, and the position of the beam is combined with the Intensity (physics), intensity of the detected signal to produce an image. In the most common SEM mode, secondary electrons emitted by atoms excited by the electron beam are detected using a secondary electron detector (Everhart–Thornley detector). The number of secondary electrons that can be detected, and thus the signal intensity, depends, among other things, on specimen topography. Some SEMs can achieve resolutions better than 1 Nanometre, nanometer. Specimens are observed in high vacuum in a Convention (norm), conventional SEM, or in low vacuum or wet conditions in ...
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