Orientador: Eliana Aparecida de Rezende Duek / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-14T11:38:37Z (GMT). No. of bitstreams: 1 Monteiro_AdrianaCristinaMottadeMenezes_D.pdf: 5297587 bytes, checksum: 9519d7cb25184a92ad96f65a3461d54a (MD5) Previous issue date: 2007 / Resumo: Dispositivos bioreabsorvíveis têm sido intensivamente estudados para aplicações em ortopedia e traumatologia, no reparo de fraturas ósseas provenientes principalmente de traumas. O poli (L-co-D, L ácido láctico), PLDLA, na relação 70:30 referentes aos monômeros L e D, L ácido láctico, respectivamente é um copolímero utilizado na fixação de fraturas nas regiões bucomaxilo e crânio. Neste trabalho o PLDLA foi sintetizado pela polimerização em massa dos monômeros cíclicos do L-ácido lático e do D, L ácido lático, utilizando como catalisador o Sn (Oct)2, sendo que os monômeros juntamente com o catalisador foram adicionados a uma ampola de vidro selada e imersa num banho de óleo a 130 oC por 72 horas. Obteve-se material com alta massa molar (105 g/mol) o qual foi caracterizado por Ressonância magnética de próton e carbono treze (RMN de 1H e 13C), Espectroscopia na região do infravermelho (FTIR), Cromatografia de permeação em gel (GPC), Calorimetria exploratória diferencial (DSC) e Análise termogravimétrica (TGA). O PLDLA foi processado por injeção obtendo-se placas e parafusos, os quais foram submetidos a testes mecânicos de flexão, GPC e Microscopia Eletrônica de Varredura (Mev), além do estudo da degradação in vitro, que demonstrou que o copolímero retém 80 % de suas propriedades mecânicas por 4 meses e do estudo in vivo, através do implante do sistema placa-parafuso em tíbias de coelhos, sendo verificado o crescimento de tecido ósseo e a ausência de reações inflamatórias no período estudado( três meses). / Abstract: The applications of bioreabsorbable polymers as temporary prostheses have been highly used in medical procedures related to fracture. Among the bioreabsorbable polymers the poly(Lco- D, L lactic acid), PLDLA, in the 70:30 rate has been studied to obtain plates and screws to recuperate traumas in the cranium and maxilla facial allowing an adaptation of devices to implant local during the surgery. In this work PLDLA was synthesized by mass polymerization of the cyclical monomers as L-lactic acid and D, L lactic acid, using Sn(Oct)2 as catalyst Polymerization were carried out in vacuum sealed, glass ampouls, it was immersed in an oil bath at 1300C, for 72 hours. It was obtained material with high molar mass (around 105 g/mol) which was characterized by: Nuclear magnetic resonance spectroscopy ( 1H RMN and 13C RMN) , Gel permeation chromatography( GPC) , FTIR , Dynamical scanning calorimetry (DSC) and Thermogravimetric analysis (TGA). PLDLA was injection molding process obtained screws plates which evaluated by mechanical tests flexural, GPC and Scanning electron microscopy (SEM). The in vitro study of the plates PLDLA maintained 80% of this strength for 4 months. An in vivo study performed in rabbits tibias showed there was formation osseous tissue and no signs of inflammation tissue were seen ( period three months). / Doutorado / Materiais e Processos de Fabricação / Doutor em Engenharia Mecânica

This research is the first systematic investigation of solid-state orientation as a novel method for controlling drug release from biodegradable polymers. The effect of various degrees of polymer orientation was studied in oriented Poly (L-lactic acid) (PLA) films containing curcumin and theophylline as model drugs. Additionally, direction specific drug release was studied from oriented PLA rods containing paracetamol. The films oriented to 2X uniaxial constant width (UCW) or 2X2Y biaxial draw ratio showed retardation of drug release, when their nematic structure was stabilised by the presence of crystalline theophylline. Contrarily, the same films when contained solid solution of curcumin, shrunk in the release medium and exhibited a release profile similar to the un-oriented films. All films oriented to the UCW draw ratio ≥ 3X contained α crystalline form of PLA and showed acceleration of drug release proportionate to the draw ratio. According to the proposed mechanism augmented formation of water filled channels in these films was responsible for faster drug release. Similarly, the paracetamol loaded PLA rods die-drawn to uniaxial draw ratios ≥ 3X exhibited enhancement of drug release. Importantly, the amount of drug released along the oriented chain axis was significantly larger than that in the perpendicular direction. Drug release from the die-drawn rods was accelerated by a greater degree than that observed from the oriented films. This can be correlated to the differences in their size, geometry and the crystalline form of PLA. In conclusion, the current study provided substantial evidence that solid-state orientation can offer a control over drug release from PLA.

Rhizopus oryzae is a filamentous fungi which produces lactic acid and ethanol in fermentations. R. oryzae has numerous advantages for use industrial production of L-(+)-lactic acid but the yield of lactic acid produced on the basis of carbon consumed is low. Metabolic flux analysis of R. oryzae has shown that most of the pyruvate produced at the end of the glycolysis is channelled to ethanol, acetyl-CoA and oxaloacetate production. This study aimed to answer some questions addressed on the regulation of pyruvate branch point in R. oryzae and for this purpose biochemical characterisation of the enzymes acting at this branch point and cloning the genes coding for these enzymes have been done. Pyruvate decarboxylase was purified and characterised for the first time from R. oryzae. The purified enzyme has a Hill coefficient of 1.84 and the Km of the enzyme is 8.6 mM for pyruvate at pH 6.5. The enzyme is inhibited at pyruvate concentrations higher than 30 mM. The optimum pH for enzyme activity shows a broad range from 5.7 and 7.2. The monomer molecular weight was estimated as 59&plusmn / 2 kDa by SDS-PAGE analysis. Pyruvate decarboxylase (pdcA and pdcB) and lactate dehydrogenase (ldhA and ldhB) genes of R. oryzae have been cloned by PCR-cloning approach and the filamentous fungi Aspergillus niger was transformed with these genes. The A. niger transformed with either of the ldh genes of R. oryzae showed enhanced production of lactic acid compared to wild type. Citric acid production was also increased in these transformants while no gluconate production was observed Cloning of hexokinase gene from R. oryzae using degenerate primers was studied by the use of GenomeWalker kit (Clontech). The results of this study were evaluated by using some bioinformatics tools depending on the unassembled clone sequences of R. oryzae genome.

Noroviren gelten neben Rotaviren, Salmonellen und Campylobacter spp. derzeit als Hauptursache infektiöser meldepflichtiger Gastroenteritiden des Menschen in Deutschland. Im Jahr 2008 wurden 212.692 Fälle norovirusbedingter Erkrankungen gemeldet (RKI 2009b). Dabei spielen lebensmittelassozierte Infektionen eine bedeutende Rolle. Besonders rohe und unerhitzt verzehrte Produkte bergen ein Risikopotential. Neben Muscheln, Salaten und Früchten konnten die Erreger auch aus Rohwurstprodukten isoliert werden. Aus mikrobiologischer Sicht sind Rohwürste bereits als Risikoprodukte bekannt. Bisher existieren jedoch nur unzureichende wissenschaftliche Ergebnisse über die Infektionsgefahr durch Viren in Lebensmitteln. In der vorliegenden Arbeit wurde die Tenazität und Inaktivierungskinetik von Noroviren anhand des Norovirus-Surrogates Felines Calicivirus untersucht. Zunächst wurde in Suspensionsversuchen der Einfluss verschiedener Konzentrationen von D/L-Milchsäure (0,1; 0,15; 0,2; 0,3 und 0,4 %), Natriumchlorid (2; 6; 12 und 20 %) und Natriumnitrit (100; 150 und 200 ppm) über einen Zeitraum von 7 Tagen bei 4 und 20 °C auf das Virus geprüft. Anschließend wurden Versuchsreihen mit artifiziell kontaminierten Rohwürsten durchgeführt. Der Infektiositätsnachweis erfolgte im Crandell-Reese-Feline-Kidney-Zellkultursystem. In den Suspensionsversuchen zeigte sich eine konzentrations-, zeit- und temperaturabhängige Wirkung der geprüften Parameter. Signifikante Infektiositätsreduktionen ergaben sich bei 20 °C- Lagerung für D/L-Milchsäure-Konzentrationen ab 0,15 % und bei 4 °C -Lagerung ab 0,3 %. Natriumchlorid bewirkte signifikante Titerreduktionen bei 20 °C-Lagerung ab einer NaCl-Konzentration von 2 %, jedoch nicht unter Kühlbedingungen. Die Reduktion der Virusinfektiosität nahm mit steigender Natriumchlorid- bzw. D/L-Milchsäurekonzentration zu. Für praxisübliche Konzentrationen von Natriumnitrit konnte keine zusätzliche Reduktion der Infektiosität nachgewiesen werden. In den Versuchsreihen mit kurz- und langgereiften Rohwürsten erwies sich FCV als sehr stabil. In beiden Produkten konnte bis zum Ende des Versuchszeitraumes nach 21 bzw. 56 Tagen infektiöses Virus nachgewiesen werden. Somit könnten Rohwurstprodukte bei einer möglichen Kontamination mit Noroviren zum Zeitpunkt des Verzehrs ein Gesundheitsrisiko für den Verbraucher darstellen. Jedoch zeigten sich auch deutliche temperatur- und zeitabhängige Wirkungen. Ein positiver Einfluss auf die Inaktivierung ist durch die Anwendung von Reife- und Lagerungstemperaturen um 22 °C zu erwarten. Es kam zu einer kontinuierlichen Virustiterreduktion von insgesamt 1,6 log10 TCID50 / g (für kurzgereifte Produkte) bzw. 3,1 log10 TCID50 / g (für langgereifte Produkte). Eine Beeinflussung der Tenazität des Norovirus-Surrogates FCV durch spezifische Herstellungs- und Lagerungsbedingungen ist somit möglich. Insbesondere die gezielte Kombination einzelner Faktoren miteinander, wie NaCl- und Milchsäuregehalt der Rohwurst, in Verbindung mit spezifischer Lagerungstemperatur und –dauer führt zu effektiver Infektiositätsminderung potentiell enthaltener Viren. Die so erzielte Risikominimierung durch Kombination ausgewählter Parameter bedeutet für die Rohwurstproduktion eine sowohl effiziente, als auch praktikable Möglichkeit, die Lebensmittelsicherheit in Bezug auf virale Infektionserreger deutlich zu erhöhen.

Orientador: Eliana Aparecida de Rezende Duek / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-14T20:10:35Z (GMT). No. of bitstreams: 1 Silva_KatiaFernanda_M.pdf: 16700696 bytes, checksum: 568261b128b361204100ac55aba7640b (MD5) Previous issue date: 2008 / Resumo: A Ciência dos Biomateriais é uma área de conhecimento multidisciplinar e está relacionada a implantes cirúrgicos e dispositivos médicos e odontológicos. Dentre as atuais aplicações dos biomateriais, a utilização de polímeros biorreabsorvíveis como arcabouço (scaffolds) para cultura de células tem se destacado como alternativa para tratamento de lesões e perda de tecidos. O objetivo deste trabalho foi obter e caracterizar arcabouços da blenda de poli(e-caprolactona) (PCL) e poli(D,L-ácido lático-co-ácido glicólico) (PLGA) nas diferentes composições (70/30, 50/50 e 30/70), preparados pelo método de fusão com adição e lixiviação de citrato de sódio. Os resultados obtidos através das análises de MEV evidenciaram que as amostras da blenda de PCL/PLGA 30/70 possuem tamanhos e quantidades de poros mais homogêneos quando comparadas às suas análogas de PCL/PLGA nas composições 50/50 e 70/30. Os materiais foram utilizados como arcabouço para cultura de osteoblastos e o estudo in vivo foi realizado pelo implante em tíbia de ratos. A cultura de células nas blendas de PCL/PLGA 70/30 e 30/70 mostraram um padrão de adesão e proliferação satisfatório, com intensa atividade celular comparado com a blenda na composição 50/50. No estudo in vivo as amostras de PCL/PLGA 30/70 com cultura apresentaram um crescimento celular mais intenso quando comparada com as blendas nas composições 70/30 com cultura, e nas diferentes composições sem cultura de células. Os resultados mostraram que a técnica utilizada no preparo das amostras é útil na confecção de arcabouços altamente porosos. Em função das análises in vitro e in vivo as blendas de PCL/PLGA 30/70 foram os arcabouços mais indicados para aplicações na engenharia de tecidos ósseos. / Abstract: The use of bioreabsorbable polymers as scaffolds for the cells culture has received special attention as an alternative for the treatment of lesions and the loss of tissue. The aim of this work was to obtain and to characterize porous scaffolds of poly(e-caprolactone) (PCL) and poly(D,Llactic acid-co-glycolic acid) (PLGA), blends, in different composition (30/70, 50/50 e 70/30), prepared by melting method with addition and leaching of sodium citrate. The morphology of samples obtained by SEM showed that PCL/PLGA 30/70 blends presented size and size distribution of porous more homogeneous when compared to PCL/PLGA 50/50 and 30/70. The culture of cells in PCL/PLGA 70/30 and 30/70 showed a satisfactory adhesion and proliferation, with intense cellular activity compared to PCL/PLGA 50/50. In the in vivo study, the samples of PCL/PLGA 30/70 showed a higher cellular grown compared to the results obtained in in vivo study of 70/30 blends with cells, 70/30 and 30/70 without cells. The results showed that the proposed technique allowed the preparation of highly porous scaffolds and the in vitro and in vivo showed that PCL/PLGA 30/70 blends were the most suitable scaffolds for applications in the bone tissue engineering. / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

Orientador: Sheila Canevese Rahal / Resumo: O trabalho teve por objetivo comparar, por meio de exames de imagem e avaliações histológicas, dois parafusos de interferência bioabsorvíveis implantados em ovinos. Foram utilizados 22 ovinos, misto de Santa Inês, adultos, fêmeas, com massa corpórea média de 42,3 kg. Em todos os animais, o membro pélvico direito recebeu o parafuso de PDLLA (70% de L-lactídeo e 30% de DL-lactídeo) e o membro pélvico esquerdo recebeu parafuso de PDLLA 70/30 + β-TCP (30% de beta fostato tricálcico), os quais foram aplicados na região metafisária distal do fêmur por acesso lateral. Os animais foram submetidos à eutanásia, de acordo com o tempo de observação e permanência dos implantes, como segue: 1 mês (n=6), 4 meses (n=5), 7 meses e meio (n=6), 18 meses (n=5). Pelo exame radiográfico, o local de inserção do parafuso PDLLA mostrava-se inicialmente como área radiolucente circular, que progressivamente apresentou-se menos definido e com presença de radiopacidade central. Pela tomografia computadorizada (TC) havia área de hipodensidade no período inicial, que com o passar do tempo apresentou aumento da densidade no eixo central. No último tempo de avaliação, a microTC mostrou acentuado aumento da densidade do parafuso, principalmente nas regiões corticais. Na avaliação histologia o parafuso estava degradado, com áreas de formação óssea discretas e outras mais evidentes. O parafuso de PDLLA/β-TCP foi facilmente identificado nas avaliações iniciais pelos exames de imagem, sendo tanto radiopaco como h... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to compare two bioabsorbable interference screws implanted in sheep. Twenty-two Santa Inês mixed sheep, adults, females, mean body mass of 42.3 kg were used. In all sheep, the right hind limb received PDLLA screw (70% L-lactide and 30% D,L-lactide) and the left hind limb received PDLLA70/30 + β-TCP (30% beta-tricalcium phosphate) screw, which were applied in the distal metaphyseal region of the femur by lateral access. The animals were submitted to euthanasia, according to observation time and permanence of the implants, as follows: 1 month (n = 6), 4 months (n = 5), 7.½ months (n = 6), 18 months (n = 5). On radiographs, the PDLLA screw insertion site was initially visibilized as a circular radiolucent area, which progressively was less defined and had central radiopacity. Computed tomography (CT) showed an area of hypodensity in the early period, and over time showed increased density in the central axis. At the last evaluation time, the microCT showed a marked increase in screw density, especially in the cortical regions. In the histology, the screw was degraded, with discrete bone formation areas and others more evident. The PDLLA/β-TCP screw was easily identified in the initial evaluations by imaging exams, being radiopaque and hyperdense, with progressive loss of definition by radiographic examination and density change on CT. In the last evaluation, the screw remained hypodense and surrounded by discrete bone tissue on microCT. Histologically, its centr... (Complete abstract click electronic access below) / Doutor

No description available.

Made available in DSpace on 2016-12-08T15:56:18Z (GMT). No. of bitstreams: 1 KATIUSCA WESSLER MIRANDA.pdf: 4397696 bytes, checksum: da27bc7c1adc7efa3e74ecfcf87feb0e (MD5) Previous issue date: 2015-08-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper studied ring opening polymerizations L-lactide (LLA) and ε-caprolactone (ε-CL) by bulk polymerization and solution polymerization, in order to evaluate the influence of initiator concentration, reaction time and reaction temperature on the yield and molecular weight of both polymers. Tin octoate and methanol was employed as initiators. It was observed that LLA and ε-CL speed ring opening polymerization, increases with temperature and that the monomer/polymer conversion immediately occurs in the first hours of synthesis when 2% of initiator is used. The molar mass, determined by capillary viscometry, was approximately 7x103 g/mol, for both polymers. It was also studied the copolymerization of LLA and ε-CL by solution polymerization employing different solvents. Weight percentages of LLA/ε-CL equal to 100/0, 95/5, 90/10, 85/15 and 80/20 were studied. The toluene was the only solvent that enabled the production of polymers and copolymers at 120 ° C. Initiator concentration equal to 0.015% and reaction time equal to 24 hours, were assessed, generating polymers with average molar mass (Mw) around 2x104 g / mol, determined by GPC. It was observed by proton and carbon 13 nuclear magnetic resonance (13 C-NMR and 1H-NMR) that reactions conducted with ε-CL concentrations lower than 15% do not yield copolymer, only PLLA. Bulk polymerization it was also studied and the main difference compared to solution polymerization is associated with the molar mass of the copolymer P(LLA-co-εCL)80/20. This product had a higher molar mass when synthesized by the first technique. After the study of copolymerization, the functionalization of nanocrystalline cellulose particles (CNC) with LLA and ε-CL, by polymerization in solution, was studied. Three compositions were analyzed: (i) PLLA-CNC, (II) P(LLA-co-εCL)85/15-CNC and (III) P(LLA-co εCL)80/20-CNC; the reactions were conducted at 120 ° C for 24 hours. It was possible to functionalize CNC particles in situ, using 80/20 LLA/ε-CL systems, with tin octoate (0.015 wt%) as catalyst and toluene as solvent (composition III). The functionalization was confirmed by Fourier transform infrared spectroscopy (FTIR). The compatibility of the P(LLA-co-εCL)80/20-CNC particle increased in toluene, confirming the reduction of hydrophilicity of these particles. Unlike occurred with the compositions (I) and (II), the composition (III) only allowed the production CNC functionalized particles. PLLA, PCL and / or P (LLA-co-εCL) were not produced. This fact indicates that the concentration of ε-CL and the presence of cellulose hydroxyl groups decreased the reactivity between the monomers. / Neste trabalho foram estudadas as reações de abertura de anel dos monômeros L-lactídeo (LLA) e ε-caprolactona (ε-CL), pela técnica de polimerização em massa com o intuito de avaliar a influência da concentração de iniciador, do tempo e da temperatura de reação sobre o rendimento reacional e a massa molar de ambos os polímeros. O iniciador empregado neste estudo foi o octoato de estanho e como co-iniciador, metanol foi empregado. Foi observado que a velocidade de reação de obtenção do poli(L-ácido láctico) (PLLA) e da poli(ε-caprolactona) (PCL) aumenta em função da temperatura e que com 2% de iniciador a conversão de monômero em polímero ocorre logo nas primeiras horas de síntese. A massa molar determinada por viscosimetria capilar foi de aproximadamente 7x103 g/mol para ambos os polímeros. Também foi estudada a obtenção de copolímeros de LLA e ε-CL por reações de polimerização em solução empregando diferentes solventes. As porcentagens mássicas de LLA/ε-CL empregadas foram 100/0, 95/5, 90/10, 85/15 e 80/20. O tolueno foi o único solvente que possibilitou a produção de polímeros e copolímeros a 120 °C. Para estas sínteses a concentração de iniciador foi igual a 0,015% e o tempo de reação foi de 24 horas, gerando polímeros com massa molar ponderal média (Mw) ao redor de 2x104 g/mol, determinadas por GPC. Foi observado por ressonância magnética nuclear de hidrogênio e de carbono 13 (RMN1H e RMN13C) que as reações conduzidas com concentrações de ε-CL inferiores à 15% não rendem copolímero, apenas PLLA é produzido. A obtenção de copolímeros pela técnica de polimerização em massa também foi estudada e a principal diferença em relação a polimerização em solução está associada à massa molar do copolímero P(LLA-co-εCL)80/20, sendo que o produto da polimerização em massa apresentou massa molar mais elevada que o obtido pela polimerização em solução. Após o estudo da obtenção dos copolímeros, foi estudada a funcionalização de partículas de celulose nanocristalina (CNC) com os monômeros de LLA e ε-CL pela técnica de polimerização em solução. Foram analisadas três composições: (I) PLLA-CNC, (II) P(LLA-co-εCL)85/15-CNC e (III) P(LLA-co-εCL)80/20-CNC; as reações foram conduzidas a 120°C durante 24 horas. Foi possível funcionalizar partículas de CNC in situ, empregando 80% de LLA, 20% de ε-CL, 0,015% de octoato de estanho e tolueno como solvente (composição III). A funcionalização foi confirmada por análises de espectroscopia de infravermelho por transformada de Fourier (FTIR). Testes de dispersão do P(LLA-co-εCL)80/20-CNC em tolueno confirmaram a diminuição da hidrofilicidade destas partículas. Ao contrário do ocorrido com as composições (I) e (II), a composição (III) permitiu somente a produção partículas de CNC funcionalizadas. PLLA, PCL e/ou P(LLA-co-εCL) não foram produzidos. Este fato indica que o aumento da concentração de ε-CL e a presença de grupos hidroxilas de celulose diminuíram a reatividade entre os monômeros.

Orientador: Eliana Aparecida de Resende Duek / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-09T22:07:51Z (GMT). No. of bitstreams: 1 Barauna_GrazielledosSantos_M.pdf: 1217156 bytes, checksum: ded7e97c7818fe0c3d87cb97d8c8f8aa (MD5) Previous issue date: 2007 / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

Noroviren gelten neben Rotaviren, Salmonellen und Campylobacter spp. derzeit als Hauptursache infektiöser meldepflichtiger Gastroenteritiden des Menschen in Deutschland. Im Jahr 2008 wurden 212.692 Fälle norovirusbedingter Erkrankungen gemeldet (RKI 2009b). Dabei spielen lebensmittelassozierte Infektionen eine bedeutende Rolle. Besonders rohe und unerhitzt verzehrte Produkte bergen ein Risikopotential. Neben Muscheln, Salaten und Früchten konnten die Erreger auch aus Rohwurstprodukten isoliert werden. Aus mikrobiologischer Sicht sind Rohwürste bereits als Risikoprodukte bekannt. Bisher existieren jedoch nur unzureichende wissenschaftliche Ergebnisse über die Infektionsgefahr durch Viren in Lebensmitteln. In der vorliegenden Arbeit wurde die Tenazität und Inaktivierungskinetik von Noroviren anhand des Norovirus-Surrogates Felines Calicivirus untersucht. Zunächst wurde in Suspensionsversuchen der Einfluss verschiedener Konzentrationen von D/L-Milchsäure (0,1; 0,15; 0,2; 0,3 und 0,4 %), Natriumchlorid (2; 6; 12 und 20 %) und Natriumnitrit (100; 150 und 200 ppm) über einen Zeitraum von 7 Tagen bei 4 und 20 °C auf das Virus geprüft. Anschließend wurden Versuchsreihen mit artifiziell kontaminierten Rohwürsten durchgeführt. Der Infektiositätsnachweis erfolgte im Crandell-Reese-Feline-Kidney-Zellkultursystem. In den Suspensionsversuchen zeigte sich eine konzentrations-, zeit- und temperaturabhängige Wirkung der geprüften Parameter. Signifikante Infektiositätsreduktionen ergaben sich bei 20 °C- Lagerung für D/L-Milchsäure-Konzentrationen ab 0,15 % und bei 4 °C -Lagerung ab 0,3 %. Natriumchlorid bewirkte signifikante Titerreduktionen bei 20 °C-Lagerung ab einer NaCl-Konzentration von 2 %, jedoch nicht unter Kühlbedingungen. Die Reduktion der Virusinfektiosität nahm mit steigender Natriumchlorid- bzw. D/L-Milchsäurekonzentration zu. Für praxisübliche Konzentrationen von Natriumnitrit konnte keine zusätzliche Reduktion der Infektiosität nachgewiesen werden. In den Versuchsreihen mit kurz- und langgereiften Rohwürsten erwies sich FCV als sehr stabil. In beiden Produkten konnte bis zum Ende des Versuchszeitraumes nach 21 bzw. 56 Tagen infektiöses Virus nachgewiesen werden. Somit könnten Rohwurstprodukte bei einer möglichen Kontamination mit Noroviren zum Zeitpunkt des Verzehrs ein Gesundheitsrisiko für den Verbraucher darstellen. Jedoch zeigten sich auch deutliche temperatur- und zeitabhängige Wirkungen. Ein positiver Einfluss auf die Inaktivierung ist durch die Anwendung von Reife- und Lagerungstemperaturen um 22 °C zu erwarten. Es kam zu einer kontinuierlichen Virustiterreduktion von insgesamt 1,6 log10 TCID50 / g (für kurzgereifte Produkte) bzw. 3,1 log10 TCID50 / g (für langgereifte Produkte). Eine Beeinflussung der Tenazität des Norovirus-Surrogates FCV durch spezifische Herstellungs- und Lagerungsbedingungen ist somit möglich. Insbesondere die gezielte Kombination einzelner Faktoren miteinander, wie NaCl- und Milchsäuregehalt der Rohwurst, in Verbindung mit spezifischer Lagerungstemperatur und –dauer führt zu effektiver Infektiositätsminderung potentiell enthaltener Viren. Die so erzielte Risikominimierung durch Kombination ausgewählter Parameter bedeutet für die Rohwurstproduktion eine sowohl effiziente, als auch praktikable Möglichkeit, die Lebensmittelsicherheit in Bezug auf virale Infektionserreger deutlich zu erhöhen.