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Cycasin
Cycasin is a carcinogenic and neurotoxic glucoside found in cycads such as ''Cycas revoluta'' and ''Zamia pumila''. Symptoms of poisoning include vomiting, diarrhea, weakness, seizures, and hepatotoxicity. In metabolic conditions, cycasin is hydrolyzed into glucose and methylazoxymethanol (MAM), the latter of which dissociates into formaldehyde and diazomethane. It induces hepatotoxicity and Zamia staggers, a fatal nervous disease affecting cattle resulting from browsing on the leaves or other parts of cycads. Sources Cycasin is found in all known cycad genera and is distributed throughout the body of the plant, but with the highest concentration in the seeds. It is one of several toxins found in cycad plants, along with the neurotoxic amino acid BMAA. The origin and biological role of these toxins is unknown, as there does not appear to be a statistically significant correlation between the concentration of toxic material and the types of herbivory observed in animals consuming th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl-ONN-azoxymethanol Beta-D-glucosyltransferase
In enzymology, a methyl-ONN-azoxymethanol beta-D-glucosyltransferase () is an enzyme that catalyzes the chemical reaction :UDP-glucose + methyl-ONN-azoxymethanol \rightleftharpoons UDP + cycasin Thus, the two substrates of this enzyme are UDP-glucose and methyl-ONN-azoxymethanol, whereas its two products are UDP and cycasin. This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is UDP-glucose:methyl-ONN-azoxymethanol beta-D-glucosyltransferase. Other names in common use include cycasin synthase, uridine diphosphoglucose-methylazoxymethanol glucosyltransferase, and UDP-glucose-methylazoxymethanol glucosyltransferase. References * EC 2.4. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycas Revoluta
''Cycas revoluta'' (Sotetsu apanese ソテツ sago palm, king sago, sago cycad, Japanese sago palm) is a species of gymnosperm in the family Cycadaceae, native to southern Japan including the Ryukyu Islands. It is one of several species used for the production of sago, as well as an ornamental plant. The sago cycad can be distinguished by a thick coat of fibers on its trunk. The sago cycad is sometimes mistakenly thought to be a palm, although the only similarity between the two is that they look similar and both produce seeds. The leaves grow from the trunk and start out as small leaves near the centre of the plant. Names Cycads' only relations to the true palms (Arecaceae) is that both are vascular plants and seed plants. The Latin specific epithet ''revoluta'' means "curled back", in reference to the leaves. This is also called kungi (comb) palm in Urdu speaking areas. Description This very symmetrical plant supports a crown of shiny, dark green leaves on a thick shaggy t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sago
Sago () is a starch extracted from the pith, or spongy core tissue, of various tropical palm stems, especially those of ''Metroxylon sagu''. It is a major staple food for the lowland peoples of New Guinea and the Maluku Islands, where it is called ''saksak'', ''rabia'' and ''sagu''. The largest supply of sago comes from Southeast Asia, particularly Indonesia and Malaysia. Large quantities of sago are sent to Europe and North America for cooking purposes. It is traditionally cooked and eaten in various forms, such as rolled into balls, mixed with boiling water to form a glue-like paste ( papeda), or as a pancake. Sago is often produced commercially in the form of "pearls" (small rounded starch aggregates, partly gelatinized by heating). Sago pearls can be boiled with water or milk and sugar to make a sweet sago pudding. Sago pearls are similar in appearance to the pearled starches of other origin, e.g. cassava starch (tapioca) and potato starch. They may be used interchang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eumaeus Atala
''Eumaeus atala'', also known as the Atala butterfly or coontie hairstreak, is a small colorful butterfly in the family Lycaenidae. It is found in southeastern Florida (including the Florida Keys) in the United States, and the Bahamas, Cuba, and the Cayman Islands in the West Indies. Its coloration and habits are unique among butterflies within its range. History The species was originally described by the Cuban zoologist Felipe Poey. He named the butterfly for Atala, the Native American heroine of an 1801 French novella ('' Atala, ou Les Amours de deux sauvages dans le desert'' or in English: "Atala, or the Loves of two Indian savages in the desert") of the same name by Chateaubriand. Ecology Throughout its range, the larvae feed on a native cycad, ''Zamia integrifolia'' (commonly called "coontie palm" or "arrowhead"), as well as the introduced ''Zamia pumila'' and other exotic ornamental cycads. In Cuba, the cycad ''Cycas revoluta'' is also eaten. Adult butterflies take flow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylazoxymethanol
Methylazoxymethanol, MAM, is a carcinogen which reduces DNA synthesis. Its derivatives include methylazoxymethanol acetate and cycasin, which they are found in cycad Cycads are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male o .... References {{Reflist Amine oxides Primary alcohols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zamia Staggers
Zamia staggers is a fatal nervous disease affecting cattle in areas where they browse on the leaves or fruit of cycads—in particular, those of the genus Zamia (thus the name). It is characterised by irreversible paralysis of the hind legs because of the degeneration of the spinal cord. It is caused by the toxins cycasin and macrozamin, β-glycosides (the sugars of which are glucose and primeverose, respectively) of methylazoxymethanol (MAM), and which are found in all cycad genera. Following ingestion the sugar is removed by bacterial glycosidase in the gut, with the MAM being absorbed. The metabolized toxin produces tumours of the liver, kidney, intestine and brain after a latent period which may be a year or longer. The disease has been known in Australia since the 1860s and was the subject of a Queensland Government investigation during the 1890s. See also * beta-Methylamino-L-alanine * Methyl-ONN-azoxymethanol beta-D-glucosyltransferase In enzymology, a methyl-ONN-az ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylazoxymethanol
Methylazoxymethanol, MAM, is a carcinogen which reduces DNA synthesis. Its derivatives include methylazoxymethanol acetate and cycasin, which they are found in cycad Cycads are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male o .... References {{Reflist Amine oxides Primary alcohols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zamia Staggers
Zamia staggers is a fatal nervous disease affecting cattle in areas where they browse on the leaves or fruit of cycads—in particular, those of the genus Zamia (thus the name). It is characterised by irreversible paralysis of the hind legs because of the degeneration of the spinal cord. It is caused by the toxins cycasin and macrozamin, β-glycosides (the sugars of which are glucose and primeverose, respectively) of methylazoxymethanol (MAM), and which are found in all cycad genera. Following ingestion the sugar is removed by bacterial glycosidase in the gut, with the MAM being absorbed. The metabolized toxin produces tumours of the liver, kidney, intestine and brain after a latent period which may be a year or longer. The disease has been known in Australia since the 1860s and was the subject of a Queensland Government investigation during the 1890s. See also * beta-Methylamino-L-alanine * Methyl-ONN-azoxymethanol beta-D-glucosyltransferase In enzymology, a methyl-ONN-az ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zamia
''Zamia'' is a genus of cycad of the family Zamiaceae, native to North America from the United States (in Georgia and Florida) throughout the West Indies, Central America, and South America as far south as Bolivia. The genus is considered to be the most ecologically and morphologically diverse cycads, and is estimated to have originated about 68.3 million years ago. Description The genus comprises deciduous shrubs with aerial or subterranean circular stems, often superficially resembling palms. They produce spirally arranged, pinnate leaves which are pubescent, at least when young, having branched and simple, transparent and coloured hairs. The articulated leaflets lack a midrib, and are broad with subparallel dichotomous venation. Lower leaflets are not reduced to spines, though the petioles often have prickles. The emerging leaves of many ''Zamia'' species are striking, some emerging with a reddish or bronze cast ('' Z. roeslii'' being an example). ''Zamia picta'' is even more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylation
In the chemical sciences, methylation denotes the addition of a methyl group on a substrate, or the substitution of an atom (or group) by a methyl group. Methylation is a form of alkylation, with a methyl group replacing a hydrogen atom. These terms are commonly used in chemistry, biochemistry, soil science, and the biological sciences. In biological systems, methylation is catalyzed by enzymes; such methylation can be involved in modification of heavy metals, regulation of gene expression, regulation of protein function, and RNA processing. In vitro methylation of tissue samples is also one method for reducing certain histological staining artifacts. The reverse of methylation is demethylation. In biology In biological systems, methylation is accomplished by enzymes. Methylation can modify heavy metals, regulate gene expression, RNA processing and protein function. It has been recognized as a key process underlying epigenetics. Methanogenesis Methanogenesis, the process th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ataxia
Ataxia is a neurological sign consisting of lack of voluntary coordination of muscle movements that can include gait abnormality, speech changes, and abnormalities in eye movements. Ataxia is a clinical manifestation indicating dysfunction of the parts of the nervous system that coordinate movement, such as the cerebellum. Ataxia can be limited to one side of the body, which is referred to as hemiataxia. Several possible causes exist for these patterns of neurological dysfunction. Dystaxia is a mild degree of ataxia. Friedreich's ataxia has gait abnormality as the most commonly presented symptom. The word is from Greek α- negative prefix+ -τάξις rder= "lack of order". Types Cerebellar The term cerebellar ataxia is used to indicate ataxia due to dysfunction of the cerebellum. The cerebellum is responsible for integrating a significant amount of neural information that is used to coordinate smoothly ongoing movements and to participate in motor planning. Although a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diazonium Compound
Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halide. General properties and reactivity Arenediazonium cations and related species According to X-ray crystallography the linkage is linear in typical diazonium salts. The bond distance in benzenediazonium tetrafluoroborate is 1.083(3) Å, which is almost identical to that for dinitrogen molecule (N≡N). The linear free energy constants σm and σp indicate that the diazonium group is strongly electron-withdrawing. Thus, the diazonio-substituted phenols and benzoic acids have greatly reduced p''K''a values compared to their unsubstituted counterparts. The p''K''a of phenolic proton of 4-hydroxybenzenediazonium is 3.4, versus 9.9 for phenol itself. In other words, the diazonium group lowers the p''K''a (enhances the acidity) by a million-fold. The stabi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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