Материалы II студенческой межфакультетсткой конференции первокурсников по биоорганической химии
NIACIN (NICOTINIC ACID) Inah Kedei Ubi, group 13. Scientific adviser is Tishakova Tatyana
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NIACIN (NICOTINIC ACID)Inah Kedei Ubi, group 13. Scientific adviser is Tishakova Tatyana.Niacin (also known as vitamin B3 and nicotinic acid) is an organic compound with the formula C6H5NO2 and, depending on the definition used, one of the 20 to 80 essential human nutrients. Not enough niacin in the diet can cause nausea, skin and mouth lesions, anemia, headaches, and tiredness. Chronic Niacin deficiency leads to a disease called pellagra. The lack of niacin may also be observed in pandemic deficiency disease which is caused by a lack of five crucial vitamins: niacin, vitamin C, thiamin, vitamin D and vitamin A, and is usually found in areas of widespread poverty and malnutrition. Wikipedia 2014. Niacin (nicotinic acid) is used to prevent and treat niacin deficiency (pellagra). Niacin may also be used to improve cholesterol and lower fat levels (triglycerides) in the blood under the care of your doctor. It is generally used after non-drug treatments have not been fully successful at lowering cholesterol. Doses for treating these blood fat problems are usually much higher than for dietary problems. Niacin deficiency may result from certain medical conditions (such as alcohol abuse, malabsorption syndrome, Hartnup disease), poor diet, or long-term use of certain medications (such as isoniazid).Niacin deficiency can cause diarrhea, confusion (dementia), tongue redness/swelling, and peeling red skin. Vitamins help to support the body's ability to make and break down natural compounds (metabolism) needed for good health. PurineIpinge Emilie, group 14. Scientific adviser is Grabovetskaya Eugenia.Heterocyclic form the largest group of organic compounds and many have important biological properties.The main heteroatom that occur in heterocyclic compounds is nitrogen, but there are also ring containing oxygen and sulfur. They are classified in accordance with the following features of their skeleton: according to the ring size, according to the number of heteroatoms and their mutual arrangement in ring, according to a degree of unsaturation of a matter and according to the number of the rings. Purine Derivative: purine itself is not found in nature .it have two derivative adenine and guanine represent purine components of nucleic acids in addition to three pyrimidine nucleic bases. purine and its derivative are subjected to prototropic tautomerism caused by hydrogen migration between the N-7 and N-9. Uric acid, xanthine(2,6-dihydroxypurine),and hypoxanthine(6-hydroxypurine)they are product of nucleic metabolism. Uric are poorly soluble in water but well soluble in bases with formation of acidic and neutral salt urates. Salt of uric acid especially acidic one can be deposited in joints in case of gout and as kidney stone.naturally occurring derivative purine derivatives are N-methylated consist of alkaloids: caffieine, theophylline and theobromine ,they are used as drugs. Natural source of this alkaloids is tea leafs, coffee and cacao beans. caffein lessen fatigue, enhances mental alterness, known as CNS stimulator. Its used in morphine poisoning and drowsiness due to sedative. Theophiline is devoid of stimulating properties. In conclusion derivative of purine and pyrimidine are essential part of DNA and RNA. Purine is a fused aromatic system consisting of pyrimidine and imidasole HISTAMINEAashish Papneja, group 15. Scientific adviser is Kozub Svetlana.Histamine is an organic nitrogenous compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine is involved in the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by basophils and by mast cells found in nearby connective tissues. Histamine increases the permeability of the capillaries to white blood cells and some proteins, to allow them to engage pathogens in the infected tissues. PROPERTIES Histamine forms coloured hygroscopic crystals that melt at 84 °C, and are easily dissolved in water or ethanol, but not in ether. In aqueous solution, histamine exists in two tautomeric forms: Nπ-H-histamine and Nτ-H-histamine. The imidazole ring has two nitrogens. The nitrogen farthest away from the side chain is the 'tele' nitrogen and is denoted by a lowercase tau sign. The nitrogen closest to the side chain is the 'pros' nitrogen and is denoted by the pi sign. The position of the nitrogen with the hydrogen on it determines how the tautomer is named. If the nitrogen with the hydrogen is in the tele position, then histamine is in the tele-tautomer form. The tele-tautomer is preferred in solution. SYNTHESIS AND METABOLISM Histamine is derived from the decarboxylation of the amino acid histidine, a reaction catalyzed by the enzyme L-histidine decarboxylase. It is a hydrophilic vasoactive amine. Bacteria also are capable of producing histamine using histidine decarboxylase enzymes unrelated to those found in animals. A non-infectious form of foodborne disease, scombroid poisoning, is due to histamine production by bacteria in spoiled food, particularly fish. Fermented foods and beverages naturally contain small quantities of histamine due to a similar conversion performed by fermenting bacteria or yeasts. Sake contains histamine in the 20–40 mg/L range; wines contain it in the 2–10 mg/L range. Histamine receptors in insects, like Drosophila melanogaster, are ligand-gated chloride channels that act to reduce neuronal activity. Histamine-gated chloride channels are implicated in the transmission of peripheral sensory information in insects, especially in photoreception/vision. Two receptor subtypes have been identified in Drosophila: HClA and HClB. There are no known GPCRs for histamine in insects. жүктеу/скачать 3.18 Mb. Достарыңызбен бөлісу:
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