748 research outputs found
The formation and decomposition kinetics of N-choloro amino acids
RĂ©szletesen vizsgáltuk az N-klĂłraminosavak kĂ©pzĹ‘dĂ©s- Ă©s bomláskinetikáját. MegerĹ‘sĂtettĂĽk, hogy az N-klĂłraminosavak kĂ©pzĹ‘dĂ©se a protonált HOCl Ă©s a deprotonált aminosav között játszĂłdik le egy bruttĂł másodrendű reakciĂłban. BizonyĂtottuk, hogy fiziolĂłgiás körĂĽlmĂ©nyek között a lizin klĂłrozása nagy valĂłszĂnűsĂ©ggel csak az α-aminocsoporton törtĂ©nik meg. A hisztidin – HOCl reakciĂł tanulmányozása során bizonyĂtottuk, hogy kĂ©t, pH-fĂĽggĹ‘, párhuzamos reakcióúton megy vĂ©gbe a folyamat, vagyis adott körĂĽlmĂ©nyek között megtörtĂ©nhet az N-klĂłramin kĂ©pzĹ‘dĂ©se Ă©s az aromás oldallánc klĂłrozása is.We obtained on the formation and decomposition kinetics and mechanisms of N-chloro amino acids. We have confirmed that the formation of N-chloro amino acids occurs in an overall second order reaction. We have proved that the α-amino group of lysine is chlorinated under physiological conditions. We have shown that the chlorination process proceeds via two pH-dependent parallel paths in the histidine – HOCl system.d
Mikotoxinok az Európai Unió Gyors Veszélyjelző Rendszerében
A mikotoxinok mikroszkopikus gombák által termelt egĂ©szsĂ©gkárosĂtĂł anyagok. Az egĂ©szsĂ©gkárosĂtĂł hatás jellege, termĂ©szete Ă©s erĹ‘ssĂ©ge változĂł, de kiemelendĹ‘ a karcinogĂ©n, genotoxikus Ă©s immunrendszer-károsĂtĂł tulajdonságuk, amely már rendkĂvĂĽl kis mennyisĂ©gű mikotoxin bevitele esetĂ©n is elĹ‘fordulhat. EzĂ©rt ezen anyagok Ă©lelmiszerekben törtĂ©nĹ‘ elĹ‘fordulását az EurĂłpai UniĂł szigorĂşan szabályozza Ă©s rendszeresen ellenĹ‘rzi. Az Ă©lelmiszerekben elĹ‘fordulĂł mikotoxinok szabályozására az Ă©lelmiszerekben elĹ‘fordulĂł szennyezĹ‘ anyagok maximális határĂ©rtĂ©kĂ©t meghatározĂł, 1881/2006/EK rendelete vonatkozik, mely egyes termĂ©kcsoportok aflatoxin, ochratoxin A, patulin, valamint deoxinivalenol, zearalenon, fumonizin,T-2 Ă©s HT-2 tartalmára Ăr elĹ‘ kötelezĹ‘ határĂ©rtĂ©keket. Bizonyos termĂ©kcsoportokra egyedi határozatok is szĂĽlettek, melyek a határon törtĂ©nĹ‘ tĂ©teles ellenĹ‘rzĂ©st is elĹ‘Ărják. A szigorĂtott határellenĹ‘rzĂ©sek miatt a megvizsgált Ă©s kifogásolt áru nem jut be az EU belsĹ‘ piacára, de a tĂ©telek nagyobb rĂ©sze sajnálatos mĂłdon elkerĂĽlheti az ellenĹ‘rzĂ©st. Az Ă©lelmiszerekben leggyakrabban Ă©szlelt mikotoxin az aflatoxin, mivel a szabályozás aflatoxinok esetĂ©ben Ăr elĹ‘ az EU kĂĽlsĹ‘ határain kötelezĹ‘ vizsgálatot. Az ochratoxinnal kapcsolatos esetek aránya a belsĹ‘ piacokon vett mintákban számottevĹ‘. ÉrthetĹ‘ mĂłdon, az EU Ă©lelmiszer- Ă©s takarmány gyorsvĂ©szjelzĹ‘ rendszerĂ©n, RASFF, keresztĂĽl a legtöbb bejelentĂ©s a határozatokkal szabályozott, kötelezĹ‘en vizsgálandĂł diĂł- Ă©s mogyorĂłfĂ©lĂ©kkel kapcsolatosan, valamint fĹ‘leg aflatoxinokra vonatkozĂłan Ă©rkezik. Ezen kĂvĂĽl jelentĹ‘sebb mennyisĂ©gben szárĂtott gyĂĽmölcsökben, fűszerekben, illetve Ăşjabban gabonábĂłl kĂ©szĂĽlt termĂ©kekben találtak mikotoxint. A közlemĂ©ny rĂ©szletes elemzĂ©st ad a RASFF rendszer adatai alapján az UniĂłba irányulĂł Ă©s az UniĂł terĂĽletĂ©n találhatĂł mikotoxin-szennyezett tĂ©telekrĹ‘l, valamint bemutatja ezen adatok relevanciáját az EurĂłpai UniĂł lakosságának mikotoxin terhelĂ©sĂ©vel kapcsolatban. Mycotoxins are natural compounds produced by microscopical fungi and may cause various adverse toxicological manifestations in humans and animals. The nature, the severity and scope of their adverse activity vary and in general, even in small amount they have potent carcinogenic, genotoxic effect and injure the immune system. In order to provide high level of health protection for consumers, the European Union has established strict regulatory limits, whose implementation is enforced. The Commission Regulation No 1881/2006 set maximum levels for some mycotoxins, i.e. for aflatoxins, ochratoxin A, patulin, deoxynivalenol, zearalenone, fumonisins, T-2 and HT-2 toxins in foodstuffs. Particular product categories are regulated under specific decisions ordaining control of imported consignments at the point of entry. Due to the fact that only aflatoxins are addressed in the specific decisions, they are the most frequently detected and notified mycotoxins in the EU Rapid Alert System for Food and Feed (RASFF). The second most frequent group, Ochratoxin A is typically detected during internal EU market controls. Most RASFF notifications concern product categories falling under specific EU decisions, especially the Aflatoxin content of nuts and nut products. Significant amount of aflatoxins can be found also in dried fruits, spices and herbs, and cereal products in 2006. The article reviews and analyses the data available in rapid alert system concerning mycotoxins notification, and evaluates the usefulness of this information for risk assessment. The value of RASFF system is unquestionable and it fulfils its intended function included in its name. The system is a significant source of valuable information, but for risk assessment purposes, other additional information is needed. It could be used most effectively for risk assessment, if it was to provide data on the ratio of all/tested/positive lots and if the authorities provided not only the positive results, but also the exact mycotoxins level of every analysed sample
Élelmiszer eredetű lisztéria fertőzések megelőzése az élelmiszerláncban
A Listeria monocytogenes (L.m.) által okozott sĂşlyos, gyakran halálos fertĹ‘zĂ©sek Ă©lelmiszerrel is terjednek, amit 1980 Ăłta bizonyĂtottnak tekinthetĂĽnk. KözvetĂtĂĄ Ă©lelmiszerkĂ©nt általában a további hĂĄkezelĂ©s nĂ©lkĂĽl fogyaszthatĂł, hosszabb tárolásra alkalmas termĂ©kek, az Ăşn. readyto-eat (RTE) Ă©lelmiszerek jönnek számĂtásba. A L.m. a környezetben Ă©s az Ă©lelmiszerekben gyakran megtalálhatĂł baktĂ©rium, Ă©s csak a szokásosnál jĂłval szigorĂşbb higiĂ©niai intĂ©zkedĂ©sekkel lehet megakadályozni az Ă©lelmiszerek szennyezĂĄdĂ©sĂ©t. Az utĂłbbi idĂĄben az EurĂłpai UniĂłban a L.m. által okozott fertĂĄzĂ©sek (liszteriĂłzisok) szignifikáns szaporodását Ă©szleltĂ©k. A közlemĂ©ny a legfrissebb nemzetközi irodalmi Ă©s statisztikai adatok figyelembevĂ©telĂ©vel elemzi a lisztĂ©ria fertĂĄzĂ©s lĂ©trejöttĂ©t Ă©s a humán liszteriĂłzisok alakulását EurĂłpában Ă©s hazánkban; egyĂşttal ismerteti a liszteriĂłzis megelĂĄzĂ©sĂ©re alkalmazhatĂł mĂłdszereket az elåállĂtás során, illetve a magánháztartásokban. Serious, often even fatal diseases caused by Listeria monocytogenes (L.m.) are spreading by foodstuffs as well that has been proven since 1980. The so-called ready-to-eat (RTE) foodstuffs with long shelf life can be considered to be intermediate agents which can be eaten without further heat treatment. The L.m. is a bacterium that can be often found in both environment and foodstuffs; food contamination can be prevented only with more severe hygienic measures than usual. Significant proliferation of L.m. infections (listeriosis) has recently been detected in the European Union. This study analyses the occurrence of Listeria infections and the development of the human listeriosis in Europe and in Hungary considering the latest international literature and statistics; at the same time, methods to present listeriosis during production and in private households are also reviewed
Excerpts from the history of food safety
Just as obtaining and consuming food is part of everyday human life, so have foodborne diseases been occurring regularly throughout history. Most of these sank into oblivion, however, certain events of greater importance, or ones that affected a large number of people or were memorable because of their nature, novelty or long-term effects have been included in source materials preserving our history in written form. There are references to diseases in the holy books that constitute the basis for certain religions (e.g., the Bible or the Quran), as well as detailed food preparation and eating rules aimed at preventing diseases. Because of the rudimentary nature of scientific knowledge, sometimes it took several centuries until the cause of an epidemic disease could be determined and the measures necessary for prevention could be taken. These diseases were often outbreaks of microbial origin, but toxicoses also occurred frequently, and in many cases they had serious, long-term consequences. This paper mentions several such events, for example, chronic lead poisoning that presumably played a role in the fall of the Roman Empire, or mass diseases accompanied by different syndromes caused by mold toxins. Unfortunately, this phenomenon was not eliminated by the development of science and technology, so foodborne illnesses still occur and, because of globalization and world trade, they can reach practically any part of the world in a short time. The article also discusses the risks of industrial development and also some of the major food counterfeiting cases that occurred recently and which lead to mass diseases
Új utak a kockázatbecslésben
A tudás Ă©s a technikai lehetĹ‘sĂ©gek fejlĹ‘dĂ©sĂ©vel egyre többfĂ©le szennyezĹ‘anyagot vagyunk kĂ©pesek megismerni Ă©s kimutatni. Ezek egyenkĂ©nt törtĂ©nĂĄ toxikolĂłgiai vizsgálata idĂĄ- Ă©s költsĂ©gigĂ©nyes, állatkĂsĂ©rleteket Ă©s emberi munkaráfordĂtást igĂ©nyel. EzĂ©rt keresik a kutatĂłk azokat a mĂłdszereket, melyekkel a kĂĽlönösen kis mennyisĂ©gben elĂĄfordulĂł szennyezĂ©sek esetĂ©n vizsgálatok nĂ©lkĂĽl is biztonsággal ĂtĂ©lhetik meg azok megengedhetĂĄ beviteli Ă©rtĂ©ket. Az Ăşn. Threshold of Toxicological Concern, TTC (toxikolĂłgiai aggálykĂĽszöb) elmĂ©let alkalmazására nĂ©hány országban már jogi lehetĂĄsĂ©g van, más országok Ă©s nemzetközi szervezetek (köztĂĽk az EurĂłpai UniĂł) jelenleg fontolgatja annak használhatĂłságát. Az elmĂ©let azonban nem alkalmazhatĂł a genotoxikus karcinogĂ©n anyagokra, amelyek esetĂ©ben a legkisebb mennyisĂ©grĂĄl sem állĂthatjuk biztosan, hogy ártalmatlan. Ebben az esetben a Margin of Exposure (MoE), expozĂciĂłs kĂĽszöb fogalmát Ă©s elmĂ©letĂ©t vezette be az EurĂłpai Élelmiszerbiztonsági HatĂłság. Mindezen eszközök Ă©s mĂłdszerek elĂĄsegĂthetik az Ă©lelmiszerjog alkalmazásának egyszerĂ©sĂtĂ©sĂ©t, a kockázatkezelĂĄi prioritások meghatározását, Ă©s a hatĂ©konyabb kommunikáciĂłt. With the advance of knowledge and techniques it is possible to recognize and detect an increasing amount of contaminants and pollutants. The toxicological examination of these substances one by one is timeconsuming and expensive, and requires animal experiments and human resources. Therefore researchers are investigating new techniques which in case of contaminations occurring in specifically small quantities help evaluate safely without testing their permissible input value. In certain countries it is already legally possible to apply the theory of the so-called Threshold of Toxicological Concern (TTC), while other countries and international organizations (e.g. the European Union) are considering its practicability. However, this theory cannot be used in the case of genotoxic carcinogen substances where it cannot be stated with safety that even their least amount is harmless. The European Food Safety Authority introduced the concept and theory of Margin of Exposure (MoE) for these substances. All these tools and methods may help simplify the application of food regulations, the determination of risk assessment priorities, and a more effective communication
Phosphates in our foods: benefits and risks
Phosphorus-containing food additives are authorized substances widely used in the food industry, the use of which has many technological advantages. For a long time, these compounds had been regarded as practically harmless, however, recently more and more research results warn us that their extensive use and increasing consumption increases the risk of certain civilization hazards, such as cardiovascular diseases and osteoporosis at the population level. This publication clarifies the authorization process of these additives and the role of phosphates, presents some results of related research and formulates recommendations to prevent potential risks
A paprika mikotoxin-tartalma egészségügyi kockázatának becslése a magyarországi aflatoxin és ochratoxin vizsgálatok alapján
A mikotoxinok termĂ©szetes eredetű mĂ©reganyagok, melyek rendkĂvĂĽl kis mennyisĂ©gben is kĂ©pesek populáciĂłs szintű egĂ©szsĂ©gkárosodást okozni. Ennek megelĹ‘zĂ©se Ă©rdekĂ©ben az EurĂłpai UniĂłban Ă©s hazánkban is szigorĂş szabályozást Ă©s ellenĹ‘rzĂ©si rendszert vezettek be. Az ellenĹ‘rzĂ©si rendszer jelzĂ©sei szerint 2004-ben magas szennyezettsĂ©gű paprika tĂ©telek kerĂĽltek forgalomba, melyek eltávolĂtására drasztikus Ă©s nagy visszhangot kiváltĂł kormányzati intĂ©zkedĂ©seket vezettek be. A vizsgálati eredmĂ©nyek elemzĂ©sĂ©bĹ‘l megállapĂthatĂł, hogy 2004-ben kiemelkedĹ‘en magas, a korábbi Ă©vek átlagos alapszennyezettsĂ©gĂ©t közel nĂ©gyszeresen meghaladĂł aflatoxin tartalmĂş tĂ©teleket találtak a hatĂłságok. A határozott intĂ©zkedĂ©seket követĹ‘en 2005-ben az átlagos szennyezettsĂ©g már jelentĹ‘sen csökkent Ă©s 2006 elsĹ‘ fĂ©lĂ©vĂ©re visszatĂ©rt a korábbi, 2000-2003 Ă©vekben tapasztalt szennyezettsĂ©gi Ă©rtĂ©kre. Az átlagos szennyezettsĂ©g aflatoxin B1 esetĂ©ben 2000-2003 átlagában 0,76 µg/kg volt, mely 2004-re 2,48 µg/kg-ra emelkedett. A paprika ochratoxin A (OTA) kontamináciĂłja is jelentĹ‘s. A vizsgált tĂ©telek szennyezettsĂ©gĂ©nek átlaga a 10 µg/kg nemzeti határĂ©rtĂ©k felett volt mind 2004-ben, mind 2005-ben. OTA esetĂ©n a csökkenĹ‘ tendencia nem Ă©rvĂ©nyesĂĽl. MindkĂ©t vizsgált mikotoxin eloszlására jellemzĹ‘, hogy kiugrĂłan magas szennyezettsĂ©gű tĂ©telek fordulnak elĹ‘ (AFB 96,28 µg/kg, OTA 248 µg/kg). Ochratoxin A esetĂ©n az átlagos szennyezettsĂ©g 2004-ben 12,5 µg/kg, 2005-ben 10,02 µg/kg volt. A hazai paprikafogyasztás az eurĂłpai átlagnak több, mint nĂ©gyszerese (1,3 g/nap, vs <0,3 g/nap). A pontos kockázatbecslĂ©st – kĂĽlönösen az egyĂ©b Ă©lelmiszercsoportokkal valĂł összehasonlĂtást – hátráltatta a mintavĂ©telezĂ©sbĹ‘l Ă©s nyilvántartásbĂłl eredĹ‘ pontatlanság, a tervezett monitoring vĂ©grehajtásának, valamint a rĂ©szletes hazai Ă©lelmiszer-beviteli adatok hiánya. A közlemĂ©ny javaslatokat fogalmaz meg a további teendĹ‘ket Ă©s kutatási feladatokat illetĹ‘en. Mycotoxins are fungal metabolites of natural origin that can cause deterioration of public health of the population even in extremely small quantities. The European Union has introduced strict legislation and control measures to prevent the health effect. The market surveillance system discovered in 2004 some lots of paprika which were contaminated by aflatoxin and ochratoxin on extremely high level. The government implied drastic measures including withdrawal all ground paprika from the market untill the satisfactory result of analysis was available. The article summarizes and evaluates the analytical results of aflatoxin and ochratoxin level in paprika. In 2004 the mean aflatoxin contamination exceeded fourfold the basic contamination level (2,48 µg/kg versus 0,76 µg/kg), but due to the firm measures it decreased in 2005 and returned to the basic level in 2006. Extreme high ochratoxin contamination was found in the paprika in 2004 (12,5 µg/kg) and similarly high in 2005 (10,02 µg/kg) as well. This means that the OTA concentration exceeded even the Hungarian regulatory limit for spices (10 µg/kg). The Hungarian ground paprika consumption is significantly higher than the European average. The mycotoxins contamination of paprika substantially contributes to the aflatoxin and ochratoxin intake of the Hungarian population
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