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Cucurbitacin F
Cucurbitacin is a class of biochemical compounds that some plants – notably members of the pumpkin and gourd family, Cucurbitaceae – produce and which function as a defence against herbivores. Cucurbitacins are chemically classified as triterpenes, formally derived from cucurbitane, a triterpene hydrocarbon – specifically, from the unsaturated variant cucurbit-5-ene, or 19(10→9β)-abeo-10α-lanost-5-ene. They often occur as glycosides. They and their derivatives have been found in many plant families (including Brassicaceae, Cucurbitaceae, Scrophulariaceae, Begoniaceae, Elaeocarpaceae, Datiscaceae, Desfontainiaceae, Polemoniaceae, Primulaceae, Rubiaceae, Sterculiaceae, Rosaceae, and Thymelaeaceae), in some mushrooms (including Russula and Hebeloma) and even in some marine mollusks. Cucurbitacins may be a taste deterrent in plants foraged by some animals and in some edible plants preferred by humans, like cucumbers and zucchinis. In laboratory research, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cucurbitane Grundstruktur Num
Cucurbitane is a class of chemical compounds with formula (Chemical Abstracts Service, CAS number 65441-59-0). It is a polycyclic hydrocarbon, polycyclic hydrocarbon, specifically triterpene. It is also an isomer of lanostane (specifically 19(10→9β)-abeolanostane), from which it differs by the formal shift of a methyl group (carbon number 19) from the 10 to the 9β position in the standard steroid numbering scheme.Satish Kumar and Raj Kumar (1991), ''Dictionary of Biochemistry''. Anmol Publications, India The name is applied to two stereoisomers, distinguished by the prefixes 5α- and 5β-, which differ by the handedness of the bonds at a particular carbon atom (number 5 in the standard steroid numbering scheme). File:5alpha-cucurbitane.svg, 5α-Cucurbitane File:5beta-cucurbitane.svg, 5β-Cucurbitane Derivatives Natural compounds Compounds with the basic cucurbitane skeleton are found in many plants, and some are important phytomedicine, phytopharmaceuticals. Natural cu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desfontainiaceae
''Desfontainia'' is a genus of flowering plants in the family Columelliaceae, though it was placed formerly in Loganiaceae, Potaliaceae (later subsumed in Gentianaceae), or a family of its own, Desfontainiaceae. The genus was named for the French botanist, René Louiche Desfontaines. It is hardy to , and requires winter protection in areas with significant frosts. Species Species in the genus include: # ''Desfontainia fulgens'' D.Don - Chile, Argentina (Neuquén, Río Negro) # ''Desfontainia spinosa'' Ruiz & Pav. - from Costa Rica to Chile + Argentina # ''Desfontainia splendens'' Humb. & Bonpl. - from S Mexico to Bolivia The best known species, ''D. spinosa'' ('Chilean holly'), is a native of rainforests and mountain slopes in southern Central America and South America, occurring from Costa Rica in the north to certain islands of Tierra del Fuego (shared by Chile and Argentina) in the extreme South, being present also in Panama, Colombia, Venezuela, Peru, Bolivia and Ecuador ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operon
In genetics, an operon is a functioning unit of DNA containing a cluster of genes under the control of a single promoter. The genes are transcribed together into an mRNA strand and either translated together in the cytoplasm, or undergo splicing to create monocistronic mRNAs that are translated separately, i.e. several strands of mRNA that each encode a single gene product. The result of this is that the genes contained in the operon are either expressed together or not at all. Several genes must be ''co-transcribed'' to define an operon. Originally, operons were thought to exist solely in prokaryotes (which includes organelles like plastids that are derived from bacteria), but since the discovery of the first operons in eukaryotes in the early 1990s, more evidence has arisen to suggest they are more common than previously assumed. In general, expression of prokaryotic operons leads to the generation of polycistronic mRNAs, while eukaryotic operons lead to monocistronic mRNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Factors, General
General transcription factors (GTFs), also known as basal transcriptional factors, are a class of protein transcription factors that bind to specific sites (Promoter (genetics), promoter) on DNA to activate Transcription (genetics), transcription of genetic information from DNA to messenger RNA. GTFs, RNA polymerase, and the Mediator (coactivator), mediator (a multi-protein complex) constitute the basic transcriptional apparatus that first bind to the promoter, then start transcription. GTFs are also intimately involved in the process of gene regulation, and most are required for life. A transcription factor is a protein that binds to specific DNA sequences (Enhancer (genetics), enhancer or promoter), either alone or with other proteins in a complex, to control the rate of transcription of genetic information from DNA to messenger RNA by promoting (serving as an Activator (genetics), activator) or blocking (serving as a repressor) the recruitment of RNA polymerase. As a class of pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytotoxic
Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (''Bitis arietans'') or brown recluse spider (''Loxosceles reclusa''). Cell physiology Treating cells with the cytotoxic compound can result in a variety of cell fates. The cells may undergo necrosis, in which they lose membrane integrity and die rapidly as a result of cell lysis. The cells can stop actively growing and dividing (a decrease in cell viability), or the cells can activate a genetic program of controlled cell death (apoptosis). Cells undergoing necrosis typically exhibit rapid swelling, lose membrane integrity, shut down metabolism, and release their contents into the environment. Cells that undergo rapid necrosis in vitro do not have sufficient time or energy to activate apoptotic machinery and will not express apoptotic markers. Apoptosis is characterized by well defined cytological and molecular events including a change i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basic Research
Basic research, also called pure research or fundamental research, is a type of scientific research with the aim of improving scientific theories for better understanding and prediction of natural or other phenomena. In contrast, applied research uses scientific theories to develop technology or techniques which can be used to intervene and ''alter'' natural or other phenomena. Though often driven simply by curiosity,"Curiosity creates cures: The value and impact of basic research , , |
Zucchini
The zucchini (; plural: zucchini or zucchinis), courgette (; plural: courgettes) or baby marrow (''Cucurbita pepo'') is a summer squash, a vining herbaceous plant whose fruit are harvested when their immature seeds and epicarp (rind) are still soft and edible. It is closely related, but not identical, to the marrow; its fruit may be called ''marrow'' when mature. Ordinary zucchini fruit are any shade of green, though the golden zucchini is a deep yellow or orange. At maturity, they can grow to nearly in length, but they are normally harvested at about . In botany, the zucchini's fruit is a pepo, a berry (the swollen ovary of the zucchini flower) with a hardened epicarp. In cookery, it is treated as a vegetable, usually cooked and eaten as an accompaniment or savory dish, though occasionally used in sweeter cooking. Zucchini occasionally contain toxic cucurbitacins, making them extremely bitter, and causing severe gastero-enteric upsets. Causes include stressed growing con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cucumber
Cucumber (''Cucumis sativus'') is a widely-cultivated Vine#Horticultural climbing plants, creeping vine plant in the Cucurbitaceae family that bears usually cylindrical Fruit, fruits, which are used as culinary vegetables.Cucumber " ''Encyclopædia Britannica''. [1998] 2019. Considered an annual plant, there are three main varieties of cucumber—slicing, Pickled cucumber, pickling, and Seedless fruit, seedless—within which several cultivars have been created. The cucumber originates from South Asia, but now grows on most continents, as many different types of cucumber are traded on the global market. In North America, the term ''wild cucumber'' refers to plants in the Genus, genera ''Echinocystis'' and ''Marah (plant), Marah'', though the two are not closely related. Description The cucumber is a Vine# ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mushroom
A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. ''Toadstool'' generally denotes one poisonous to humans. The standard for the name "mushroom" is the cultivated white button mushroom, ''Agaricus bisporus''; hence the word "mushroom" is most often applied to those fungi ( Basidiomycota, Agaricomycetes) that have a stem ( stipe), a cap ( pileus), and gills (lamellae, sing. lamella) on the underside of the cap. "Mushroom" also describes a variety of other gilled fungi, with or without stems, therefore the term is used to describe the fleshy fruiting bodies of some Ascomycota. These gills produce microscopic spores that help the fungus spread across the ground or its occupant surface. Forms deviating from the standard morphology usually have more specific names, such as "bolete", "puffball", "stinkhorn", and " morel", and gilled mushrooms themselves are often called "agarics" in refere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymelaeaceae
The Thymelaeaceae are a cosmopolitan family of flowering plants composed of 50 genera (listed below) and 898 species.Zachary S. Rogers (2009 onwards)A World Checklist of Thymelaeaceae (version 1) Missouri Botanical Garden Website, St. Louis. It was established in 1789 by Antoine Laurent de Jussieu.Antoine Laurent de Jussieu ''Genera Plantarum'', page 76. Herrisant & Barrois, Paris. The Thymelaeaceae are mostly trees and shrubs, with a few vines and herbaceous plants. Description This is not intended as a full botanical description, but only as a few notes on some of the conspicuous or unusual traits of the family when ''Tepuianthus'' is excluded. The bark is usually shiny and fibrous. Attempts to break the stem often result in a strip of bark peeling down the side.Ernst Schmidt, Mervyn Lotter and Warren McCleland The number of stamens is usually once or twice the number of calyx lobes. If twice, then they often occur in two well separated series. Exceptions include ''Gonystylu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosaceae
Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. Among the most species-rich genera are ''Alchemilla'' (270), ''Sorbus'' (260), '' Crataegus'' (260), ''Cotoneaster'' (260), ''Rubus'' (250), and ''Prunus'' (200), which contains the plums, cherries, peaches, apricots, and almonds. However, all of these numbers should be seen as estimates—much taxonomic work remains. The family Rosaceae includes herbs, shrubs, and trees. Most species are deciduous, but some are evergreen. They have a worldwide range but are most diverse in the Northern Hemisphere. Many economically important products come from the Rosaceae, including various edible fruits, such as apples, pears, quinces, apricots, plums, cherries, peaches, raspberries, blackberries, loquats, strawberries, rose hips, hawthorns, and almonds. The family also includes popular ornamental trees and shrubs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sterculiaceae
Sterculiaceae was a family of flowering plant based on the genus ''Sterculia''. Genera formerly included in Sterculiaceae are now placed in the family Malvaceae, in the subfamilies: Byttnerioideae, Dombeyoideae, Helicteroideae and Sterculioideae. As traditionally circumscribed the Sterculiaceae, Malvaceae, Bombacaceae, and Tiliaceae comprise the "core Malvales" of the Cronquist system and the close relationship among these families is generally recognized. Sterculiaceae may be separated from Malvaceae ''sensu stricto'' by the smooth surface of the pollen grains and the bilocular anthers. Numerous phylogenetic studies have revealed that Sterculiaceae, Tiliaceae and Bombacaceae as traditionally defined are cladistically polyphyletic. The APG and APG II systems unite Bombacaceae, Malvaceae ''sensu stricto'', Sterculiaceae and Tiliaceae into a more widely circumscribed Malvaceae, i.e., Malvaceae ''sensu lato''. In that view the taxa formerly classified in Sterculiaceae are treated in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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