In detective novels, such as those by Agatha Christie, it is not unusual for the murderer to use potassium cyanide, which is potassium salt of hydrogen cyanide, which is also called cyan hydrogen. The taste and smell, which are always described in these contexts, are those of bitter almond. Bitter almond contains a glycoside that is broken down enzymatically when chewed or chopped up in water, at which point sugar, hydrogen cyanide and benzoic acid form. Eating bitter almonds in large quantities is therefore very dangerous. On the other hand, something you can do is to chew on the leaf buds of rowan trees (Sorbus spp.) in the spring. You will get the typical taste of bitter almond, of hydrogen cyanide, but quite harmlessly. The amount is far too small to hurt an animal as large as a human being.. Hydrogen cyanide is an example of something that is natural but not necessarily harmless.. During the first half of the 20th century, hydrogen cyanide was used as a pesticide against bed bugs. It was ...
The formation of hydrogen cyanide during the catalytic reduction of nitric oxide (NO) with carbon monoxide and hydrogen was studied with a bench-scale flow reactor. The previously reported inhibition by sulfur dioxide of the formation of hydrogen cyanide was found to be counteracted by transient admission of oxygen to the catalyst. These results are discussed in the context of the control of automotive emissions of NO and the prevention of hydrogen cyanide production during such control. ...
A hydrogen cyanide concentration of 300 mg/m3 in air will kill a human within 10-60 minutes.[43] A hydrogen cyanide concentration of 3500 ppm (about 3200 mg/m3) will kill a human in about 1 minute.[43] The toxicity is caused by the cyanide ion, which halts cellular respiration by acting as a non-competitive inhibitor for an enzyme in mitochondria called cytochrome c oxidase. Specifically CN− binds to Fe in the heme subunit in cytochromes, interrupting electron transfer. Hydrogen cyanide has been absorbed into a carrier for use as a pesticide. Under IG Farbens brand name Zyklon B (German ,Cyclone B, with the B standing for Blausäure - "Prussic Acid"),[44] it was used in the German concentration camp mass killing during World War II. The same product is currently made in the Czech Republic under the trademark "Uragan D2". Hydrogen cyanide was also the agent employed in judicial execution in some U.S. states, where it was produced during the execution by the action of sulfuric acid on an ...
Hydrogen cyanide is usually included among the CW agents causing general poisoning. There is no confirmed information on this substance being used in chemical warfare. However, it has been reported that hydrogen cyanide was used by Iraq in the war against Iran and against the Kurds in northern Iraq during the 1980s. Hydrogen cyanide has high toxicity and in sufficient concentrations it rapidly leads to death. During the Second World War, a form of hydrogen cyanide (Zyklon B) was used in the Nazi gas chambers. At room temperature, hydrogen cyanide is a colourless liquid which boils at 26 oC. The most important route of poisoning is through inhalation. Both gaseous and liquid hydrogen cyanide, as well as cyanide salts in solution, can also be taken up through the skin. Its high volatility probably makes hydrogen cyanide difficult to use in warfare since there are problems in achieving sufficiently high concentrations outdoors. On the other hand, the concentration of hydrogen cyanide may rapidly ...
Calcium cyanide also known as black cyanide, is an inorganic compound with the formula Ca(CN)2. It is a white solid, although it is rarely observed in pure form. Commercial samples can be black-gray. It is the calcium salt of cyanide. It hydrolyses readily (even on moist air) to release hydrogen cyanide. Like other similar cyanides it is very toxic. Calcium cyanide can be prepared by treating powdered calcium oxide with boiling anhydrous hydrocyanic acid in the presence of an accelerator such as ammonia or water in order to minimize the loss of the hydrocyanic acid by polymerization. It may also be prepared by reacting liquid hydrocyanic acid with calcium carbide. Alternatively calcium cyanide may be prepared by reacting hydrocyanic acid gas with quicklime (CaO) at high temperatures around 400 °C. At higher temperatures around 600 °C calcium cyanimide is formed instead. The material prepared often is contaminated with polymeric derivatives of hydrogen cyanide, hence the black color. Calcium ...
As Wikipedia explains, Hydrogen cyanide is extremely deadly: "A hydrogen cyanide concentration of 300 mg/m3 in air will kill a human within about 10 minutes. It is estimated that hydrogen cyanide at a concentration of 3500 ppm (about 3200 mg/m3) will kill a human in about 1 minute. The toxicity is caused by the cyanide ion, which halts cellular respiration by inhibiting an enzyme in mitochondria called cytochrome c oxidase. Interestingly, a key chemical use of Hydrogen cyanide was developed by none other than IG Farben, the Nazi war era criminal pharmaceutical giant that was later broken up to become todays pharmaceutical giants, including Bayer. Hydrogen cyanide is widely recognized as a chemical weapon and is even used on the tips of whaling harpoons to murder whales.". Physics fact #4: Hydrogen cyanide kills birds and humans very quickly. Is this the result of a weapons test or attack? That it is used as a chemical weapon might make some people wonder whether all this is fallout from some ...
0022] These organic reagents are preferably used in aqueous solution, in which case a base, preferably sodium hydroxide, can additionally be added. The addition of hydrogen cyanide onto glyoxylic acid and glyoxylate is very rapid and is quantitative, especially for glyoxylate. Both glyoxylic acid and the addition product are readily water-soluble, and so no precipitate forms in the reaction vessel, which ensures a reliable process. Since glyoxylic acid has a relatively high melting point (semihydrate: 70-75° C.; anhydrous substance: 98° C.) and is water-soluble, the process according to the invention can be carried out within a relatively wide temperature range, without any risk of contamination of the product gas by the organic reagent. Cooling or heating, in contrast to the known processes with volatile organic solvents, is not required. Moreover, it is not necessary during the reaction to control the pH of the reagent which reacts with hydrogen cyanide, and so the process according to the ...
At temperatures below 78�F, hydrogen cyanide is a colorless or pale-blue liquid (hydrocyanic acid); at higher temperatures, it is a colorless gas. Hydrogen cyanide is very volatile, producing potentially lethal concentrations at room temperature. The vapor is flammable and potentially explosive. Hydrogen cyanide has a faint, bitter almond odor and a bitter, burning taste. It is soluble in water and is often used as a 96% aqueous solution. Synonyms include formonitrile. Aqueous solutions are referred to as hydrocyanic acid and prussic acid.
0047]The pH of the washing solution should thus ideally be in the range from 6 to 10 to ensure acceptable washing of hydrogen cyanide and stability of the metal cyanide complexes and/or metal cyanide precipitates, while simultaneously avoiding excessive washing of carbon dioxide. Weak acid anions of the metal salts thus serve to buffer the pH of the washing solution between 6 and 10. Preferably the weak acid anions are derived from carboxylic acids, i.e. they preferably are carboxylates. Suitable carboxylates are citrate, oxalate, acetate, and propionate, most preferably acetate. A skilled person will appreciate that the concentration of the weak acid anions must be selected to achieve both the desired pH range and the required buffering capacity, and consequently will depend on inter alia the composition of the synthesis gas, especially the level of carbon dioxide, the ratio of the synthesis gas to fresh washing solution, and the operating temperature of the gas-liquid contacting stage 18, ...
We present global distributions of C|sub|2|/sub|H|sub|2|/sub| and hydrogen cyanide (HCN) total columns derived from the Infrared Atmospheric Sounding Interferometer (IASI) for the years 2008-2010. These distributions are obtained with a fast method allowing to retrieve C|sub|2|/sub|H|sub|2|/sub| abundance globally with a 5 % precision and HCN abundance in the tropical (subtropical) belt with a 10 % (25 %) precision. IASI data are compared for validation purposes with ground-based Fourier transform infrared (FTIR) spectrometer measurements at four selected stations. We show that there is an overall agreement between the ground-based and space measurements with correlation coefficients for daily mean measurements ranging from 0.28 to 0.81, depending on the site. Global C|sub|2|/sub|H|sub|2|/sub| and subtropical HCN abundances retrieved from IASI spectra show the expected seasonality linked to variations in the anthropogenic emissions and seasonal biomass burning activity, as well as exceptional events,
Hydrogen cyanide | HCN or CHN | CID 768 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety/hazards/toxicity information, supplier lists, and more.
TY - JOUR. T1 - Rotational states of dipole-bound anions of hydrogen cyanide. AU - Ard, S.. AU - Garrett, W. R.. AU - Compton, R. N.. AU - Adamowicz, L.. AU - Stepanian, S. G.. PY - 2009/5/12. Y1 - 2009/5/12. N2 - Rotational states of dipole-bound anions of HCN are studied both experimentally and theoretically. The ground state experimental electron affinity (ea), 1.56 meV, is in good agreement with present and one earlier theoretical value. The predicted binding energy for the J = 1 state, 1.2 meV, is observed, whereas J = 2 is too fragile for observation and J = 3 is unbound.. AB - Rotational states of dipole-bound anions of HCN are studied both experimentally and theoretically. The ground state experimental electron affinity (ea), 1.56 meV, is in good agreement with present and one earlier theoretical value. The predicted binding energy for the J = 1 state, 1.2 meV, is observed, whereas J = 2 is too fragile for observation and J = 3 is unbound.. UR - ...
Combined Exposures to Hydrogen Cyanide and Carbon Monoxide in Army Operations, 9780309113670, available at Book Depository with free delivery worldwide.
Hydrogen cyanide is an important feedstock in many chemical industries, synthesized from natural gas and ammonia. To recovery unreacted ammonia and pu
The RNA World concept started in 1959 when Spanish Catalan biochemist Joan Oró synthesized adenine, a key component of RNA and DNA, from hydrogen cyanide, similar to a Miller-Urey experiment at high temperatures.. By the late in the twentieth century, origin of life researchers began to examine the RNA World theory. American physicist, biochemist, and molecular biology pioneer Walter Gilbert, in 1986, was the first to coin the term "RNA World" Gilbert envisioned a RNA-first model on primordial Earth. By the actions of natural selection on RNA, DNA and protein molecules theoretically formed with the DNA molecule evolving into an information role, the protein molecules evolving into a catalytic role.. Like the Miller-Urey experiment though, the lack of geological evidence for hydrogen cyanide in the fossil record emerged as a telltale sign. Even worse, hydrogen cyanide is a gas toxic to cellular metabolism. During the German Nazi regime, hydrogen cyanide was the gas-of-choice at Auschwitz.. To ...
At ems, we carry HYDROGEN CYANIDE 0.01-3.00% as part of our quality sampling & calibration offerings. Shop now or give us a call!
NBC News commissioned laboratory tests of knock-off marijuana vapes that found a pesticide linked to hydrogen cyanide in 10 out 10 products.
As Americas vaping crisis continues, 10 unregulated vaping cartridges have tested positive for pesticides-including a fungicide that can turn into hydrogen cyanide if burned.
Hydrogen cyanide (HCN) is a ubiquitous molecule in the Universe. It is a compound that is easily produced in significant yields in prebiotic simulation experiments using a reducing atmosphere. HCN can spontaneously polymerise under a wide set of experimental conditions. It has even been proposed that HCN polymers could be present in objects such as asteroids, moons, planets and, in particular, comets. Moreover, it has been suggested that these polymers could play an important role in the origin of life. In this review, the simple organics and biomonomers that have been detected in HCN polymers, the analytical techniques and procedures that have been used to detect and characterise these molecules and an exhaustive classification of the experimental/environmental conditions that favour the formation of HCN polymers are summarised. Nucleobases, amino acids, carboxylic acids, cofactor derivatives and other compounds have been identified in HCN polymers. The great molecular diversity found in HCN polymers
Trypsin inhibitors. Trypsin inhibitors are a type of anti-nutritional factors that can inhibit the activities of some digestive enzymes in human intestines and hinder our dietary intake of nutrients. Soya beans contain trypsin inhibitors. Nonetheless, trypsin inhibitors can be destroyed by soaking the soya beans well and cooking them thoroughly in boiling water.. Cyanogenic glycosides. Cyanogenic glycosides occur naturally in over 2 000 plant species, quite a number of which are food plants. Different types of cyanogenic glycosides may be found in different cyanogenic food plants, for example, taxiphyllin in bamboo shoots, and linamarin in cassava. Cyanogenic glycosides per se are relatively non-toxic. However, upon human consumption of cyanogenic plants, non-toxic cyanogenic glycosides will be decomposed into toxic hydrogen cyanides by hydrolysis in the intestinal tracts. The potential toxicity of a cyanogenic plant depends primarily on its capacity to produce hydrogen cyanides. Cyanide ...
... IUPAC name Hydrogen cyanide Other names Hydrocyanic acidprussic acid,formonitrileformic anammonidecarbon hydride
Cyanide, also known as hydrocyanic acid, has a molecular formula HCN and its molecular weight is 27.03 g/mol. HCNs boiling point is 25.6°C (78.1°F). Hydrogen cyanide was first isolated from the pigment Prussian blue; hence another alternative name is prussic acid. In the 1800s, cyanide was given its modern name from the English word cyan, which means a shade of blue. Hydrogen cyanide and its potassium and sodium salts have been used as fumigants, insecticides, metal polishes, and in gold/silver electroplating solutions. Cyanide vapor can be detected by a characteristic almond odor, but it is estimated that up to approximately 50% of the human population cannot detect this odor due to a recessive genetic trait. Cyanide can be found in trace levels in the human body as a result of normal metabolic processes, as well as from eating a diet high in cyanogenic foodstuffs (e.g. apples, apricots, bitter almonds, and cherries) and smoking cigarettes. ...
Many cyanides are highly toxic. The cyanide anion is an inhibitor of the enzyme cytochrome c oxidase (also known as aa3) in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It attaches to the iron within this protein. The binding of cyanide to this enzyme prevents transport of electrons from cytochrome c to oxygen. As a result, the electron transport chain is disrupted, meaning that the cell can no longer aerobically produce ATP for energy.[18] Tissues that depend highly on aerobic respiration, such as the central nervous system and the heart, are particularly affected. This is an example of histotoxic hypoxia.[19]. The most hazardous compound is hydrogen cyanide, which is a gas and kills by inhalation. For this reason, an air respirator supplied by an external oxygen source must be worn when working with hydrogen cyanide.[12] Hydrogen cyanide is produced by adding acid to a solution containing a cyanide salt. Alkaline solutions ...
Of 200 water isolates screened, five strains of Pseudomonas fluorescens and one strain of Pseudomonas aeruginosa were cyanogenic. Maximum cyanogenesis by two strains of P. fluorescens in a defined growth medium occurred at 25 to 30 degrees C over a pH range of 6.6 to 8.9. Cyanide production per cell was optimum at 300 mM phosphate. A linear relationship was observed between cyanogenesis and the log of iron concentration over a range of 3 to 300 microM. The maximum rate of cyanide production occurred during the transition from exponential to stationary growth phase. Radioactive tracer experiments with [1-14C]glycine and [2-14C]glycine demonstrated that the cyanide carbon originates from the number 2 carbon of glycine for both P. fluorescens and P. aeruginosa. Cyanide production was not observed in raw industrial wastewater or in sterile wastewater inoculated with pure cultures of cyanogenic Pseudomonas strains. Cyanide was produced when wastewater was amended by the addition of components of the ...
With the start of fall comes the risk of cyanide poisoing in ruminants. Cyanide, prussic acid, hydrogen cyanide or hydrocyanic acid poisoning are all terms describing the same condition. A number of common plants, including sudangrass, johnsongrass, sorghums and sorghum-sudangrass hybrids contain cyanogenic glycosides in the outer cells of the plant. Further inside the leaf tissue are the enzymes needed to convert these compounds to the cyanide poison.
With the start of fall comes the risk of cyanide poisoing in ruminants. Cyanide, prussic acid, hydrogen cyanide or hydrocyanic acid poisoning are all terms describing the same condition. A number of common plants, including sudangrass, johnsongrass, sorghums and sorghum-sudangrass hybrids contain cyanogenic glycosides in the outer cells of the plant. Further inside the leaf tissue are the enzymes needed to convert these compounds to the cyanide poison.
An emergency involving the diagnosis and management of patients exposed to cyanide is a potential scenario for any healthcare facility. Cyanide exposure is associated with smoke inhalation, laboratory mishaps, industrial incidents, suicide attempts, and criminal activity. Cyanide is a chemical group that consists of one atom of carbon bound to one atom of nitrogen by three molecular bonds (C≡N). Inorganic cyanides (also know as cyanide salts) contain cyanide in the anion form (CN−) and are used in numerous industries, such as metallurgy, photographic developing, plastic manufacturing, fumigation, and mining. Common cyanide salts include sodium cyanide (NaCN) and potassium cyanide (KCN). Sodium salts react readily with water to form hydrogen cyanide. Organic compounds that have a cyano group bonded to an alkyl residue are called nitriles. For example, methyl cyanide is also known as acetonitrile (CH3CN). Hydrogen cyanide (HCN) is a colorless gas at standard temperature and pressure with a ...
It is accurate to say that the Germans employed Zyklon (made from a base of hydrocyanic acid and in use since 1922) to safeguard, by disinfestation, the health of large numbers of civilians, troops, prisoners, and internees. But they never used Zyklon to kill anyone, let alone to put to death throngs of human beings at once. In light of the draconian precautions for the use of hydrogen cyanide gas, the gassing of inmates as allegedly carried out at Auschwitz and at other camps would have been fundamentally impossible.[6]. It is accurate to say that the Germans envisaged a "final solution of the Jewish question" (Endlösung der Judenfrage). But this solution was a territorial one (eine territoriale Endlösung der Judenfrage), and not a murderous one. It was a project to induce or, if necessary, to force the Jews to leave Germany and its European sphere of influence, thereafter to establish, in accord with the Zionists, a Jewish national home, in Madagascar or elsewhere. With a view toward such a ...
Cyanide can be metabolised by a wide variety of organisms including bacteria, fungi, arthropods and plants using a number of different pathways. Non-toxic concentrations of cyanide can be readily biodegraded, both aerobically and anaerobically. Aerobic degradation yields CO2 and ammonia (that may be further converted to nitrate or nitrite); anaerobic biodegradation yields ammonia and methane. Degradation of cyanides in sewage treatment plants depends on the availability of adapted (micro-)organisms. Sudden high levels of cyanide in these sewage plants may lead to a loss of viability, while fully adapted sludge may tolerate and degrade concentrations up to 100 to 150 mg CN-/l with a high degree of efficiency. Vegetation is also able to remove cyanide from water or soil. Initial data indicate that cyanide-tolerant plants may be used for the remediation of cyanide-contaminated soil ...
Recommended criteria for a standard intended to protect the health of workers against exposure to hydrogen-cyanide (74908) and cyanide salts, especially sodium-cyanide (13998033), potassium-cyanide (151508) and calcium-cyanide (592018), for up to a 10-hour work shift, 40-hour work week, over a working lifetime. Occupational exposure to these compounds is defined as exposure to airborne concentrations greater than the corresponding action levels, or one- half the corresponding recommended ceiling environmental exposure limit. The main topics covered include: recommendations for levels of cyanide in the workplace air, including sampling and analysis; medical surveillance; personal protective equipment and clothing; informing employees of cyanide hazards; work practices and control procedures; sanitation, monitoring and recordkeeping; biologic effects of exposure, including epidemiology, carcinogenicity, mutagenicity, and teratogenicity; environmental data and engineering controls." - NIOSHTIC-2 ...
Abiotic and biotic environmental stressors play a key role in the ecophysiology of most organisms. As the presence and activity of stress-inducing agents vary along the day, organisms that are able to predict these periodic changes are better fit to survive. Caenorhabditis elegans, a soil-dwelling nematode, is subjected to daily changes in its natural environment, and its tolerance to osmotic and oxidative stress varies along the day. Pseudomonas fluorescens strain CHA0 is a soil bacterium that produces a set of secondary metabolites that antagonize phytopathogenic fungi and therefore promote healthy growth of several plant species. Here we show that strain CHA0 is able to affect C. elegans either under growth limiting conditions (i.e., slow-killing) or by rapid paralysis in nutrient replete conditions (fast-killing). Both types of toxicity require the post-transcriptional Gac/Rsm regulatory cascade, and the fast paralytic killing depends strongly on hydrogen cyanide production. The response ...
In the previous communication of this series (No. XII, 1908, B, Vol. 80, pp. 321-329) the contention was advanced that "emulsinprepared from sweet almonds contains at least three distinct enzymes, viz., amygdalase, a β-glucase and gluco-lactase: the first of these, amygdalase, being the enzyme by which amygdalin is resolved into glucose and Fiscliers glucoside, β-glucase that by which β-glucosides are hydrolysed, gluco-lactase that which hydrolyses milk sugar. Meanwhile the striking discovery has been made by Rosenthaler that emulsin has the property of inducing the formation of dextro-rotatory benzylidenecyanhydrol-such as may be obtained from amygdalin-from benzaldehyde and hydrogen cyanide; this raises the question whether there may not also be present in "emulsin" a specific enzyme capable of operating on the cyanophoric radicle of amygdalin and of resolving it into hydrogen cyanide and benzaldehyde. To avoid periphrasis this hypothetical enzyme may be spoken of as benzcyancise. ...
The rotational spectrum of the hydrogen cyanide dimer has been observed in the frequency range 26-40 GHz by using a Stark-modulated microwave spectrometer. Although the spectrum is very weak, even under optimum conditions, it has been possible to assign vibrational satellites in the vβ progression based on the ground state and in the vβ progression based on vσ ═ 1 with the aid of the computer simulation of spectra and the ground-state spectroscopic constants. The spectroscopic constants now available for the hydrogen cyanide dimerare summarized as follows: (HC14N)2 (DC14N)2 (HC15N)2 vβ ═ 1 ← 0/cm-1 35±5 30±5 35±5 vσ ═ 1 ← 0/cm-1 101 ─ ─ Bo/MHz 1745.80973(50) 1661.18(26) 1684.28825(25) DJ/kHz 2.133(30) (1.873) 1.900(30) rc. m./nm 44.496 ─ 44.499 Kσ/(Nm-1) 8.14 ─ 8.51 αβ/MHz ─20.07 (2) ─17.73 (27) ─18.74 (9) γβ/MHz 0.266 (4) 0.242 (36) 0.250 (17) qβ/MHz 5.33 (4) 5.44 (13) 5.15 (10) ασ/MHz (31.44) ─ ─ ...
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HCN എന്ന് രാസനാമമുള്ള ഒരു ജൈവ സംയുക്തമാണ്[7] ഹൈഡ്രജൻ സയനൈഡ് (Hydrogen cyanide). നിറമില്ലാത്ത ഈ സംയുക്തം അന്തരീക്ഷ താപനിലയേക്കാൾ അൽപ്പം ഉയർന്ന താപത്തിൽ വാതകമായി മാറുന്നു. തിളനില 25.6 °C (78.1 °F) ആയ ഹൈഡ്രജൻ സയനൈഡ് മാരകമായ വിഷമുള്ള ഒരു പദാർത്ഥമാണ്. വലിയ വിലപിടിച്ച വ്യാവസായിക ഉൽപ്പന്നമായ ഹൈഡ്രജൻ സയനൈഡ് പോളിമറുകളുടെ മുതൽ ഔഷധങ്ങളുടെ വരെ നിർമ്മാണത്തിന് ഉപയോഗിക്കുന്നു. ...
Hydrogen cyanide is manufactured from methane, ammonia, and oxygen over a catalyst of 90% Pt-10% Rh in the form of a pad of woven screens at 1050-1100°C and 2 atm. This reaction has a wide application in industrial synthesis of hydrogen cyanide. This reaction is known as Andrussow process where catalytic gauze is 3-5 mm thick, and when the high gas velocities are employed, about 8% HCN and a number of byproducts such as hydrogen, CO, and CO2 have been reported in the effluent stream. Various modifications have been studied in this reaction especially for the catalyst and the starting materials. ...
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Once, a long time ago when the earth was quite young, a group of high mountains rose above the ocean, forming a large island. It was volcanic, somewhat like a Hawaiian island of today, for continents as we know them had not yet formed. Because of the height and extent of these mountains, and because of the prevailing wind and weather patterns, a variety of climate zones existed on the island. Thunderstorms were frequent on the rainy side, where it was always cloudy. In the high altitudes, near the mountaintops, the rain froze, and the precipitation came down as snow or hail. The atmosphere was reducing, and these conditions favored the formation of hydrogen cyanide in the discharges. The rain and snow were rich in this chemical. Large glaciers descended from the highest peaks. At their base, in the summer season, lay a number of partly frozen alkaline lakes. Hydrogen cyanide collected in them, and reacted with itself extensively, until the time came when the lakes froze solid in the winter. When ...
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The soaring popularity of vaping products - both legal and knock-offs - is fueling a public health crisis that has vexed the medical community, NBC News...
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice ...
A recycling pathway for cyanogenic glycosides evidenced by the comparative metabolic profiling in three cyanogenic plant species ...
A cyanohydrin is a functional group found in organic compounds in which a cyano and a hydroxy group are attached to the same carbon atom. The general formula is R2C(OH)CN, where R is H, alkyl, or aryl. Cyanohydrins are industrially important precursors to carboxylic acids and some amino acids. Cyanohydrins can be formed by the cyanohydrin reaction, which involves treating a ketone or an aldehyde with hydrogen cyanide (HCN) in the presence of excess amounts of sodium cyanide (NaCN) as a catalyst: RRC=O + HCN → RRC(OH)CN In this reaction, the nucleophilic CN− ion attacks the electrophilic carbonyl carbon in the ketone, followed by protonation by HCN, thereby regenerating the cyanide anion. Cyanohydrins are also prepared by displacement of sulfite by cyanide salts: Cyanohydrins are intermediates in the Strecker amino acid synthesis. Acetone cyanohydrin, (CH3)2C(OH)CN is the cyanohydrin of acetone. It is generated as an intermediate in the industrial production of methyl methacrylate. In the ...
Two cyanogenic glycosides are found in black cherry. Amygdalin and prunasin are found in the leaves, twigs, and seeds (Cheeke and Schull 1985). Hydrogen cyanide is formed when the glycosides are hydrolyzed by plant enzymes after damage or by rumen organisms. Majak et al. (1990) found that cyanide production is most rapid in cattle that had been starved for a day. High rates of cyanide production were obtained in the rumen after the animal ingested fresh alfalfa and cubed alfalfa hay.. ...
White clover (Trifolium repens) is naturally polymorphic for cyanogenesis (HCN production with tissue damage). Cyanogenesis protects plants from small herbivores, but frequencies of cyanogenic plants decrease in colder climates, possibly because cyanogenesis is detrimental to plants in areas of frequent frosts. The cyanogenesis polymorphism is controlled by two genes: Ac controls the presence/absence of cyanogenic glucosides, andLi controls the presence/absence of the enzyme required for their hydrolysis (linamarase). We are currently examining the molecular evolution of the cyanogenesis loci to understand the genetic basis and evolutionary dynamics of this adaptive variation. ...
Researchers have found a new biomarker for cyanide poisoning, which may extend its detection window in death investigations by weeks if not months.. Unless cyanide is discovered at the time of death on the mouth or nose, elevated cyanide concentrations can only be found for up to two days under current toxicological testing. A team of researchers have found a substance that appears in the liver following cyanide poisoning that could serve as a stable biomarker for a longer period of time. The research, by Dr. Ilona Petrikovics, David Thompson, Sarah Martin, Prashanth Jayanna, and Jorn Yu of Sam Houston State University; Gary Rockwood of the U.S. Army Medical Research Institute of Chemical Defense; and Brian Logue of South Dakota State University, was recently published in two journals, Biomarkers and Analytical Methods.. Cyanide exposures commonly originate from smoke inhalation or direct exposure to either cyanide salt or hydrogen cyanide (HCN) and occur in military, firefighting, industrial ...
УДК: 633.352.1:631.527. For the first time in Russia there were conducted the tests on the common vetch grain use in animal feeding. The requirements to the base vetch varieties are given here, as well as the reasons for the lack of fodder grain varieties of vetch. A new vetch variety Valentina is described. The first step to the creation of a new fodder grain variety was to investigate the seed collections and the breeding stock and find vetch samples with high seed production, with high protein content of the seeds, with low HCN (hydrocyanic acid) and trypsin inhibitors content. Breeding stock estimation revealed some samples with no HCN, some - with acceptable level of trypsin inhibitors and others - with protein of high biological value. Lines 2217-82 and 2219-82, hybrids No. 476, 477, 478, and others proved to be free from cyanogenic glycosides. The minimum content of trypsin inhibitor (37…49 mg 100g-1 DM was found in hybrids No. 484, 476, 477, 478. Samples remarkable for their ...
Cyanide most commonly occurs as hydrogen cyanide and its salts-sodium and potassium cyanide. Cyanides are both man-made and naturally occurring substances. They are found in several plant species as cyanogenic glycosides and are produced by certain bacteria, fungi, and algae. In very small amounts, cyanide is a necessary requirement in the human diet. Cyanides are released to the environment from industrial sources and car emissions (ATSDR, 1989).. Cyanides are readily absorbed by the inhalation, oral, and dermal routes of exposure. The central nervous system (CNS) is the primary target organ for cyanide toxicity. Neurotoxicity has been observed in humans and animals following ingestion and inhalation of cyanides. Cardiac and respiratory effects, possibly CNS-mediated, have also been reported. Short-term exposure to high concentrations produces almost immediate collapse, respiratory arrest, and death (Hartung, 1982; EPA, 1985). Symptoms resulting from occupational exposure to lower ...
article{863763d2-0124-469c-a85a-def9adb91a2d, abstract = {The influence of the reaction conditions on the enantioselectivity of reactions catalysed by lipases or hydroxynitrile leases (HNLs) in organic solvents was investigated. The lipases catalysed kinetic resolution of chiral secondary alcohol, or chiral carboxylic acids and the HNLs catalysed asymmetric addition of hydrogen cyanide to aldehydes. The temperature effects on enantioselectivity, were studied in detail. From measurements of the enantiomeric ratio (C) at different temperatures the activation parameters DeltaDeltaH(#) and DeltaDeltaS(#) were determined. In the lipase-catalysed reactions the enthalpic and entropic effects on E always counteracted, while in a few of the HNL-catalysed reactions, DeltaDeltaH(#) and DeltaDeltaS(#) had opposite sign, and therefore the effects cooperated to give high E values (-RTInE = DeltaDeltaG(#) = DeltaDeltaH(#) - TDeltaDeltaS(#)). In all the HNL-catalysed reactions and most of the lipase-catalysed ...
Nitriles occur naturally in a diverse set of plant and animal sources. Over 120 naturally occurring nitriles have been isolated from terrestrial and marine sources. Nitriles are commonly encountered in fruit pits, especially almonds, and during cooking of Brassica crops (such as cabbage, brussel sprouts, and cauliflower), which release nitriles through hydrolysis. Mandelonitrile, a cyanohydrin produced by ingesting almonds or some fruit pits, releases hydrogen cyanide and is responsible for the toxicity of cyanogenic glycosides.[35]. Over 30 nitrile-containing pharmaceuticals are currently marketed for a diverse variety of medicinal indications with more than 20 additional nitrile-containing leads in clinical development. The nitrile group is quite robust and, in most cases, is not readily metabolized but passes through the body unchanged[citation needed]. The types of pharmaceuticals containing nitriles are diverse, from vildagliptin, an antidiabetic drug, to anastrozole, which is the gold ...