A meggymag mint ipari gamma-tokoferol forrás

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A természet szénhidrátkémikusai: enzimatikus glikozilezések = Nature's carbohydrate chemists: enzymatic glycosylation

Oligoszacharidok enzimekkel történő előállítása egy igen vonzó alternatív módszer a konvencionális kémiai megközelítés mellett, mert védő csoportok használata nélkül a célvegyület képződését eredményezi. Ezen pályázatban az anomer konfigurációt megtartó alpha amilázok transzglikozilezési képességét tanulmányoztuk humán amiláz szubsztrátok és inhibitorok előállítására. Az akarviozinil-izomaltozil- spiro-tiohidantoin szintézisét a Bacillus stearothermophilus maltogén amilázával (BSMA) oldottuk meg. A BSMA enzim az akarbóz pszeudotriszacharid részét a glüko-spiro-tiohodantoin (GTH) akceptorra transzferálta. A PTS-GTH szerkezetvizsgálata azt mutatta, hogy a glikozilezés főként a glükóz 6-os OH-ján történt az anomer konfiguráció megtartásával. Az akarbózzal meghoszabbított termék több nagyságrenddel hatékonyabb inhibitora a humán amiláznak, mint a kis méretű GTH molekula. A humán amiláz nem rendelkezik transzferáz aktivitással, de mutációval sikerült transzglikozilezési képességet ?bevezetni? a vad típusú enzimbe. A Tyr151Met mutánssal kromoforral jelzett maltooligoszacharidokat állítottunk elő és a PNP 1-tio-béta-maltooligoszacharidokat DP 2-4 izoláltuk. A Tyr151Met mutáns maltotetraóz donorról maltóz és maltotrióz egységeket transzferált különböző PNP glikozidokra. Az NMR analízisek szerint a mutáns enzim megőrízte sztereo-és regioszelektivitását. A glikozilezés a glikozil akceptor 4-es OH-ján történt.Jelenleg árpa amiláz mutánsokkal történő szintézisek folynak. | Enzyme-catalyzed synthesis of oligosaccharides allows the formation of well-defined oligosaccharides selectively without using any protection of hydroxyl groups. In this project the application of transglycosylation ability of retaining glycosidases was studied for the synthesis of oligosaccharide substrates and inhibitors of human amylases. Synthesis of acarviosinyl-isomaltosyl-spiro-thiohydantoin has been achieved by Bacillus stearothermophilus maltogenic amylase (BSMA). BSMA was capable of transferring the acarviosine-glucose residue from an acarbose donor onto glucopyranosylidene-spiro-thiohydantoin (GTH). Structural studies revealed that the enzyme reserved its stereoselectivity. Glycosylation took place mainly at C-6 position. The isolated compound was found to be a much more efficient salivary amylase inhibitor than GTH with kinetic constants of KEI=0.19 uM and KESI= 0.24 uM. Transglycosylation activity has been introduced into human salivary alpha amylase by genetic engineering. Synthesis of PNP 1-thio beta-maltooligosaccharides DP 2-4 has been carried out by a Tyr151Met mutant of HSA. Tyr151Met was capable of transferring maltose and maltotriose residues from a maltotetraose donor onto different PNP glycosides. NMR studies revealed that the mutated enzyme preserved the stereo- and regioselectivity. The glycosylation took place at position 4 of the glycosyl acceptor, exclusively. Nowadays transferase activity of barley amylase mutants has also been studied

Új mérési eljárások fejlesztése a növényi antioxidáns státusz meghatározására

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A meggy jelentősége a vaspótlásban

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Effect of anthocyanin-rich Hungarian tart cherry extract on blood antioxidant status in C57BL/6J mice

In this study male C57BL/6J (B6) mice were used to determine the possible effects of our Hungarian tart cherry extract in a chronic obesity mouse model on antioxidant capacity. The control group received standard mouse chow, the high fat control group was switched to high fat diet and tap water supplemented with 5% sucrose. The high fat+anthocyanin group received the high fat and sucrose diet, but dissolved in the drinking water they received anthocyanin-rich tart cherry extract. After six weeks, the antioxidant capacity and SOD activity were measured. Antioxidant capacity was decreased with a significant elevation of SOD activity. The tart cherry extract made a significant enhancement in antioxidant capacity and SOD activity. Our results show that chronic anthocyanin intake has a potential to enhance redox status associated with obesity

Effect of Anthocyanin-Rich Tart Cherry Extract on Inflammatory Mediators and Adipokines Involved in Type 2 Diabetes in a High Fat Diet Induced Obesity Mouse Model

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Effect of fertilization on the fat content and fatty acid profile of sorghum flour samples

In our experiments, changes in the fat content and fatty acid composition in the flour of sorghum cultivated in growing areas treated with different nitrogen fertilizer doses were studied by the gas chromatographic analysis of the fatty acid methyl esters. The fat content exhibited a slight increase as a result of increasing fertilizer treatment, there were significant differences between the individual treatments. The fatty acid composition showed different results, depending on the treatments. We found that treatments had a positive effect on the fat content of the samples, however, increasing nitrogen dosages did not result in an outstanding increase in the case of any of the fatty acids. The ratio of fatty acids to each other did not change significantly as a function of the nitrogen dose. The average amount of unsaturated fatty acids was 83%, and the amount of saturated fatty acids was 17%. The fat content of sorghum is low (1.1-1.5%), but it can still be considered to be a good source of essential fatty acids. The average amount of omega-3 and omega-6 essential fatty acids in the samples analyzed by us was 50%, which also increases the nutrition physiology effect of sorghum