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The cytochrome P-450 dependent monooxygenase system plays a key role in the bioactivation and detoxication of xenobiotics. Isozyme-specific inhibitors of cytochrome P-450 may be useful in elucidating the role of particular isozymes in xenobiotic metabolism or in suppressing the bioactivation of xenobiotics and enhancing detoxication. The antibiotic chloramphenicol is a selective mechanism-based inactivator of rat liver cytochromes P-450, inactivating 6 of the 12 isozymes monitored, including the major phenobarbital-inducible isozyme PB-B. Analogs of chloramphenicol have been tested to determine the importance of various functional groups in regulating the effectiveness and isozyme selectivity of chloramphenicol as a mechanism-based inactivator of cytochromes P-450. This information will aid in the design of more effective and isozyme specific mechanism-based inactivators. The dihalomethyl group and the propanediol moiety were found to be important in determining the efficacy of inactivation and the ability to inactivate the enzyme by virtue of the modification of the protein as opposed to the modification of the heme moiety. The propanediol side chain also plays a role in the isozyme selectivity. Unlike chloramphenicol, N (2-p-nitrophenethyl)dichloroacetamide (pNO₂DCA), which contains an ethyl group in place of the propanediol side chain of chloramphenicol, is an effective inactivator of BNF-B, the major beta-naphthoflavone-inducible isozyme, as well as PB-B, in vitro and in vivo. Alkaline hydrolysis and enzymatic digestion of the covalently modified isozymes has shown that chloramphenicol and pNO₂DCA are both metabolized by cytochromes P-450 to oxamyl chlorides which bind to lysine and other amino acid residues of the enzyme. However, the mechanism by which pNO₂DCA inactivates BNF-B differs significantly from that by which chloramphenicol inactivates PB-B, although both involve an impairment of the transfer of electrons from NADPH-cytochrome P-450 reductase, suggesting that there are differences in the active sites of these two isozymes.

The overall aim of this thesis was to investigate the fate of perfluorinated alkyl compounds (PFCs) in biological systems. During the past several years, it has been shown that wildlife are ubiquitously contaminated with two classes of PFCs, the perfluoroalkyl carboxylates (CxF2x+1C(O)OH, PFCAs) and sulfonates (CxF2x+1SO3H, PFSAs). However, there is still considerable uncertainty regarding how wildlife are accumulating these PFCs, particularly in remote areas such as the Canadian arctic. The potential for fluorotelomer acrylate monomers (CxF2x+1CH2CH2OC(O)CH=CH2, FTAcs) to act as precursors to PFCAs through atmospheric oxidation was investigated using smog chamber experiments. FTAc atmospheric fate is determined by OH radical reaction with a lifetime of approximately 1 day. The sole primary product of this reaction was the 4:2 fluorotelomer glyoxylate which is expected to undergo further atmospheric oxidation or photolysis to ultimately yield PFCAs. Temporal and spatial trends of PFCs in arctic ringed seals and seabirds were investigated to assist in understanding PFC transport mechanisms to remote regions. In ringed seals, perfluorooctane sulfonate (PFOS) levels decreased rapidly, coinciding with the phase out by the major manufacturer. These findings are consistent with volatile precursors as the dominant source of PFCs to arctic wildlife. The bioaccumulation and biotransformation of the 8:2 FTAc was investigated in two complimentary studies with rainbow trout. During the in vivo dietary exposure study, fish rapidly accumulated and biotransformed the 8:2 FTAc, with intermediate metabolites observed within 1 hour of dosing. Perfluorooctanoate (PFOA), perfluorononanoate (PFNA) and perfluoroheptanoate (PFHpA) were formed and accumulated in low yields. The carboxylesterase activity in the trout liver and stomach was investigated using in vivo sub-cellular (S9) incubations. Very high esterase activities were shown with approximately equal efficiency in the stomach and liver. The metabolic pathway of the 8:2 fluorotelomer alcohol (8:2 FTOH) was investigated by separately dosing whole rainbow trout with three intermediate metabolites that represented important branching points. The 7:3 fluorotelomer saturated carboxylate (FTCA) did not form PFOA, but formed PFHpA and the 7:3 fluorotelomer unsaturated carboxylate (FTUCA). The 8:2 FTCA and 8:2 FTUCA did form PFOA, confirming a “beta-like-oxidation” mechanism.

The overall aim of this thesis was to investigate the fate of perfluorinated alkyl compounds (PFCs) in biological systems. During the past several years, it has been shown that wildlife are ubiquitously contaminated with two classes of PFCs, the perfluoroalkyl carboxylates (CxF2x+1C(O)OH, PFCAs) and sulfonates (CxF2x+1SO3H, PFSAs). However, there is still considerable uncertainty regarding how wildlife are accumulating these PFCs, particularly in remote areas such as the Canadian arctic. The potential for fluorotelomer acrylate monomers (CxF2x+1CH2CH2OC(O)CH=CH2, FTAcs) to act as precursors to PFCAs through atmospheric oxidation was investigated using smog chamber experiments. FTAc atmospheric fate is determined by OH radical reaction with a lifetime of approximately 1 day. The sole primary product of this reaction was the 4:2 fluorotelomer glyoxylate which is expected to undergo further atmospheric oxidation or photolysis to ultimately yield PFCAs. Temporal and spatial trends of PFCs in arctic ringed seals and seabirds were investigated to assist in understanding PFC transport mechanisms to remote regions. In ringed seals, perfluorooctane sulfonate (PFOS) levels decreased rapidly, coinciding with the phase out by the major manufacturer. These findings are consistent with volatile precursors as the dominant source of PFCs to arctic wildlife. The bioaccumulation and biotransformation of the 8:2 FTAc was investigated in two complimentary studies with rainbow trout. During the in vivo dietary exposure study, fish rapidly accumulated and biotransformed the 8:2 FTAc, with intermediate metabolites observed within 1 hour of dosing. Perfluorooctanoate (PFOA), perfluorononanoate (PFNA) and perfluoroheptanoate (PFHpA) were formed and accumulated in low yields. The carboxylesterase activity in the trout liver and stomach was investigated using in vivo sub-cellular (S9) incubations. Very high esterase activities were shown with approximately equal efficiency in the stomach and liver. The metabolic pathway of the 8:2 fluorotelomer alcohol (8:2 FTOH) was investigated by separately dosing whole rainbow trout with three intermediate metabolites that represented important branching points. The 7:3 fluorotelomer saturated carboxylate (FTCA) did not form PFOA, but formed PFHpA and the 7:3 fluorotelomer unsaturated carboxylate (FTUCA). The 8:2 FTCA and 8:2 FTUCA did form PFOA, confirming a “beta-like-oxidation” mechanism.

A ocorrência de fármacos no meio ambiente têm despertado o interesse de pesquisadores, uma vez que podem causar efeitos adversos à comunidade biótica. O norfloxacino (NOR) é um fármaco amplamente empregado no tratamento de infecções bacterianas tanto em humanos como em animais, e devido as suas propriedades físico-químicas, tem sido alvo de estudos envolvendo o seu monitoramento e efeitos toxicológicos em micro-organismos, principalmente em ambientes aquáticos. Neste contexto, o presente trabalho teve como objetivo a investigação da biotransformação/biodegradação do fármaco NOR por fungos derivados de ambiente marinho. Primeiramente, foi realizada uma triagem a partir de 7 cepas fúngicas, das quais 4 foram selecionadas - Penicillium raistrickii CBMAI 931, Cladosporium sp. CBMAI 1237, Aspergillus sydowii CBMAI 1241 e Penicillium raistrickii CBMAI 1235 - para avaliar a influência da adição do fármaco na inoculação dos mesmos. Os experimentos foram realizados na presença do fármaco (0,1 mg mL-1), e em caldo nutritivo (malte 2% em água do mar artificial) por 35 dias (32°C, 130 rpm). A adição do fármaco no dia, e após a inoculação, não influenciou no crescimento dos fungos. No entanto, a formação de produtos de biotransformação foi observada para o experimento com adição do NOR no dia da inoculação, os quais foram identificados por LC-QqTOF, baseando-se na similaridade entre as massas obtidas experimentalmente e teórica, assim como os produtos já reportados na literatura. A porcentagem de biodegradação do fármaco foi determinada para o experimento com adição do fármaco após a inoculação, para os fungos: P. raistrickii CBMAI 931 (34,07%) e A. sydowii CBMAI 1241 (58,91%). Para os experimentos realizados em meio mineral (59,35%) e na presença de um consórcio de fungos (57,05%), não foram observadas diferenças significativas. Não foi possível elucidar a estrutura do produto isolado na presença do fungo A. sydowii CBMAI 1241, devido a sua baixa concentração e a possibilidade de conjugação com substâncias endógenas. Um método analítico foi desenvolvido e validado para a determinação da porcentagem de biodegradação do fármaco nos experimentos com os fungos marinhos. / The occurrence of drugs on the environment has called attention to researchers, since they can cause adverse effects to the biotic community. The norfloxacin (NOR) is a compound widely used for treatment of serious bacterial infections in human and animals. Due to the physicochemical properties of this compound it has been focus of studies concerning about its monitoring and toxicological effects on microorganisms, mainly in aquatic environment. Thus, in the present study the biotransformation/biodegradation of NOR by marine-derived fungi was investigated. Firstly, it was performed a screening with 7 strain of marine fungi, in a which 4 were selected - Penicillium raistrickii CBMAI 931, Cladosporium sp. CBMAI 1237, Aspergillus sydowi CBMAI 1241 and Penicillium raistrickii CBMAI 1235 - to evaluate the influence of NOR addition in the inoculation. The experiments were carried out in the presence of NOR (0,1 mg mL-1) in nutritive broth (malt 2% in artificial sea water) for 35 days (32°C, 130 rpm). The NOR addition on the first day and after inoculation, did not affect the fungal growth. Nevertheless, the formation of biotransformation products was observed to the experiment with addition on the first day. These products were identified by LC-QqTOF, based on the similarity between experimental and theoretical mass, as the products already reported on the literature. The percentage of drug biodegradation was determined for the fungi P. raistrickii CBMAI 931 (34,07%) and A. sydowi CBMAI 1241 (58,91%) for the experiment carried out with NOR addition after inoculation. For the experiments performed in mineral medium (59,35%) and in the presence of fungal consortium (57,05%) no differences were observed for the biodegradation. It was not able to elucidate the structure of isolated product, in the presence of A. sydowii CBMAI 1241, due to its low concentration and probable conjugation with endogenous substances. The analytical method was developed and validated to determine the percentage of drug biodegradation in the experiments with marine fungi.

No presente estudo, uma triagem foi realizada com 12 fungos marinhos Penicillium miczynskii CBMAI 930, Penicillium raistriicki CBMAI 931, Aspergillus sydowii CBMAI 933, Aspergillus sydowii CBMAI 934, Aspergillus sydowii CBMAI 935, Bionectria sp. CBMAI 936, Penicillium oxalicum CBMAI 1185, Penicillium citrinum CBMAI 1186, Penicillium decaturense CBMAI 1234, Penicillium raistriicki CBMAI 1235, Cladosporium sp. CBMAI 1237 e Aspergillus sydowii CBMAI 1241 para avaliar o potencial enzimático destes micro-organismos frente à fenilacetonitrila 1. Estes micro-organismos foram isolados de esponjas e alga coletadas do litoral norte do estado de São Paulo. A triagem foi realizada em meio sólido mineral suplementado com glicose e fenilacetonitrila 1 como única fonte de nitrogênio. Dentre os fungos, 8 adaptaram-se muito bem ao substrato 1 nas respectivas quantidades 5 µL (0,04 mmol), 10 µL (0,08 mmol) e 15 µL (0,12 mmol). Em seguida, a triagem foi realizada em meio líquido (20 µL (0,17 mmol), 40 µL (0,35 mmol) e 60 µL (0,50 mmol) de fenilacetonitrila 1 e obteve um bom crescimento de massa micelial dos fungos. Experimentos realizados na ausência de fenilacetonitrila 1, tanto em meio sólido, quanto em meio líquido, não promoveram o crescimento microbiano, evidenciando que as enzimas capazes de hidrolisarem nitrilas presente no sistema catalítico são construtivas. A fenilacetonitrila 1 foi biotransformada ao ácido 2-(2-hidroxifenil)acético 1b (51% pelo fungo A. sydowii CBMAI 934) por todos os fungos adaptados. Devido ao bom crescimento do fungo A. sydowii CBMAI 934 em meio mineral sólido e líquido na presença de fenilacetonitrila 1, este fungo foi selecionado para promover reações de hidrólise frente a diferentes organonitrilas, arilcetonitrilas: 4-fluorofenilacetonitrila 2, 4-clorofenilacetonitrila 3, 4-metoxifenilacetonitrila 4, 2-metilfenilacetonitrila 5, 3-metilfenilacetonitrila 6, 4-metilfenilacetonitrila 7 aos seus correspondentes ácidos carboxílicos 4-fluorofenilacético 2a (51%), 4-clorofenilacético 3a (55%), 4-metoxifenilacético 4a (43%), 2-metilfenilacético 5a (76%), 3-metilfenilacético 6a (52%) e 4-metilfenilacético 7a (46%), em nitrila alifática, 2-(1-ciclo-hexen-1-il)acetonitrila 8 ao ácido 2-(1-ciclo-hexen-1-il)acético 8a (28%) e nitrila hetero-aromática, 2-cianopiridina 19 a 2-piridinamida 19a. As reações foram acompanhadas por GC-FID e os produtos de biotransformações foram isolados e caracterizados por GC-MS, HRMS, RMN de 1H e de 13C. Este trabalho envolveu o primeiro estudo frente à biotransformação de nitrilas por micro-organismos de origem marinha. / In the present study, a screening of 12 marine fungi Penicillium miczynskii CBMAI 930, Penicillium raistriicki CBMAI 931, Aspergillus sydowii CBMAI 933, Aspergillus sydowii CBMAI 934, Aspergillus sydowii CBMAI 935, Bionectria sp. CBMAI 936, Penicillium oxalicum CBMAI 1185, Penicillium citrinum CBMAI 1186, Penicillium decaturense CBMAI 1234, Penicillium raistriicki CBMAI 1235, Cladosporium sp. CBMAI 1237 and Aspergillus sydowii CBMAI 1241 was done in order to evaluate the enzymatic potential of these microorganisms in phenylacetonitrile 1. These microorganisms were isolated from sponges and algae collected at the north shore of Sao Paulo State. The screening was carried out in solid mineral medium supplemented with glucose and phenylacetonitrile 1 as the only source of nitrogen. Among the fungi, 8 adapted to the subtract really well 5 µL (0,04 mmol), 10 µL (0,09 mmol) and 15 µL (0,13 mmol). Afterwards, a screening was carried out in liquid medium 20 µL (0,17 mmol), 40 µL (0,35 mmol) and 60 µL (0,50 mmol) of phenylacetonitrile 1) and a great mass of the fungi was obtained. The phenylacetonitrile 1 was biotransformed in the acid 2-(2-hydroxyphenyl)acetic 1b (51% by the fungus A. sydowii CBMAI 934) by all the adapted fungi. Experiments carried out without phenylacetonitrile 1, both in solid and liquid media did not show microbial growth. Enzymes which hydrolyzed nitriles present in the catalytic system were constructive. Due to the good growth rate of the fungus A. sydowii CBMAI 934 in solid and liquid mineral media in presence of phenylacetonitrile 1, this fungus was selected to promote hydrolysis reactions in different organonitriles, arylacetonitriles: 4-fluorophenylacetonitrile 2, 4-chlorophenylacetonitrile 3, 4-methoxyphenylacetonitrile 4, 2-methylphenylacetonitrile 5, 3-methylphenylacetonitrile 6, 4-methylphenylacetonitrile 7 in their corresponding carboxylic acids 4-fluorophenylacetic 2a (51%), 4-chlorophenylacetic 3a (55%), 4-methoxyphenylacetic 4a (43%), 2-methylphenylacetic 5a (76%), 3-methylphenylacetic 6a (52%) and 4-methylphenylacetic 7a (46%), aliphatic nitrile 2-(1-cyclohexen-1-yl)acetonitrile 8 to 2-(1-cyclohexen-1-yl)acetic acid 8a (28%) and heteroaromatic nitrile 2-cyanopiridine 19 to 2-pyridinecarboxamides 19a. The reactions were monitored by GC-FID and the biotransformation products were isolated and characterized by GC-MS, HRMS and 1H and 13C NMR. This work involved the first study on the biotransformation of nitriles by marine microorganisms.

BORGES, K. B. Análise estereosseletiva da tioridazina e seus principais metabólitos: um estudo cinético de biotransformação empregando fungos. 2006. 124f. Dissertação (Mestrado) Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto, 2006. Atualmente, existe um grande interesse em estudar a biotransformação estereosseletiva de fármacos, incluindo os processos que reproduzem as vias de metabolização in vivo. Alguns desses estudos estão sendo realizados empregando microrganismos como, por exemplo, fungos. A cromatografia líquida de alta eficiência é umas das técnicas que pode ser empregada para a resolução, identificação e quantificação das espécies quirais formadas. A tioridazina (THD) é um fármaco quiral, com atividade antipsicótica utilizado para o tratamento da esquizofrenia. Possui como principais metabólitos a tioridazina-2-sulfóxido (THD-2-SO) e tioridazina-2-sulfona (THD-2-SO2), ambos com atividade antipsicótica, e a tioridazina-5-sulfóxido (THD-5-SO), que contribui para o efeito cardiotóxico do fármaco. Portanto, o presente trabalho tem por finalidade o desenvolvimento de um método de análise estereosseletiva da THD-2-SO e THD-5-SO em meio de cultura para avaliação do potencial de biotransformação da THD por alguns fungos. A melhor resolução dos estereoisômeros da THD-2-SO e THD-5-SO foi obtida utilizando a coluna CHIRALPAK® AS e fase móvel hexano : etanol : metanol (92:6:2, v/v/v) + 0,5% de dietilamina. A extração líquido líquido foi utilizada na preparação das amostras, tendo como solvente extrator o éter etílico. O método desenvolvido apresentou recuperação em torno de 100% para todos os compostos avaliados. Os coeficientes de variação e erros obtidos nos estudos de precisão e exatidão, intra e interensaios, foram inferiores a 10%. O método desenvolvido e validado foi empregado para avaliar o potencial de biotransformação da THD por 12 fungos endofíticos isolados de Tithonia diversifolia, Viguiera arenaria e Viguiera robusta e 1 fungo de solo (Penicillium waksmanii). Dentre os 13 fungos avaliados, quatro merecem destaque por apresentarem um potencial de biotransformação estereosseletivo mais evidenciado: Phomopsis sp. (TD2) apresentou maior mono-5-sulfoxidação para as formas (S)-(SE) e (R)-(FE) (9,3% e 5,8%, respectivamente);Glomerella cingulata (VA1) apresentou maior mono-5-sulfoxidação para as formas (S)-(SE) + (R)-(FE) (39,7%); Diaporthe phaseolorum (VR4) apresentou maior mono-2-sulfoxidação para as formas (S)-(SE) e (R)-(FE) (84,4% e 82,5%, respectivamente) e Aspergillus fumigatus (VR12) apresentou maior mono-2-sulfoxidação das formas (S)-(FE) (20,7%) e (R)-(SE) (34,4%). / BORGES, K. B. Stereoselective analysis of thioridazine and its major metabolites: a kinetic study of biotransformation by fungi. 2006. 124p. Dissertation (Masters degree) Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto, 2006. The interest in stereoselective biotransformation of drugs including the processes that reproduce the in vivo metabolism has been increased. To study drug metabolism several models have been used. Among them, studies carried out using microorganisms, mainly fungi have been standing out. High-Performance Liquid Chromatography can be used for the resolution, identification and quantification of the chiral species formed. The thioridazine (THD) is a chiral drug used as antipsychotic for the treatment of schizophrenia. The main metabolites of THD are thioridazine-2-sulfoxide (THD-2-SO), thioridazine-2-sulfone (THD-2-SO2) and thioridazine-5-sulfoxide (THD-5-SO). The THD-2-SO and THD-2-SO2 possesss antipsychotic activity and THD-5-SO contributes to the cardiotoxicity of drug more than the parent compound. Therefore, the aim of the present work was to develop a method for the stereoselective analysis of THD-2-SO and THD-5-SO in culture medium to study biotransformation of THD by some fungi. The simultaneous determination of thioridazine-2-sulfoxide and thioridazine-5-sulfoxide was performed on a CHIRALPAK® AS column using a mobile phase constituted of hexane: ethanol: methanol (92:6:2, v/v/v) + 0.5% diethylamine. Diethyl ether was used as extraction solvent. Recoveries around 100% were obtained for all the evaluated species. The coefficients of variation and relative errors in precision and accuracy studies (within-day and between-day) were below 10%. The validated method was used to evaluate the biotransformation of THD by 12 endophytic fungi isolated from Tithonia diversifolia, Viguiera arenaria and Viguiera robusta and 1 fungus isolated from soil (Penicillium waksmanii). Among the 13 fungi evaluated, four of them deserve prominence for presenting an evidenced stereoselective biotransformation potential: Phomopsis sp. (TD2) presented greater mono-5-sulfoxidation to the forms (S)-(SE) e (R)-(FE) (9.3% and 5.8%, respectively); Glomerella cingulata (VA1) presented greater mono-5-sulfoxidation to the forms (S)-(SE) + (R)-(FE) (39.7%); Diaporthe phaseolorum (VR4) presented greater mono-2-sulfoxidation to the forms (S)-(SE) and (R)-(FE) (84.4% and 82.5%, respectively) and Aspergillus fumigatus (VR12) presented greater mono-2-sulfoxidation to the forms (S)-(FE) (20.7%) and (R)-(SE) (34.4%).

A risperidona é um medicamento antipsicótico que quando metabolizada da origem a dois metabólitos hidroxilados quirais, a 7-hidroxirisperidona (7-RispOH) e a 9-hidroxirisperidona (9-RispOH). A 9-RispOH apresenta as mesmas propriedades farmacológicas que a risperidona e já é comercializada como fármaco, com o nome genérico de paliperidona. Estudos em humanos mostram que existem diferenças na disposição cinética dos enantiômeros da 9-RispOH, com uma maior prevalência do enantiômero (+)-9-RispOH em plasma. Dessa forma, este trabalho teve como finalidade avaliar a capacidade de algumas espécies de fungos e também de catalisadores de Jacobsen em (bio)transformar enantiosseletivamente a risperidona em seu metabólito ativo 9-RispOH. Para tanto, foi desenvolvido um método de separação para a risperidona e seus metabólitos utilizando cromatografia líquida de alta eficiência quiral. Este método foi então aplicado nos estudos de biotransformação enantiosseletivo e nos estudos de catálise assimétrica. A separação cromatográfica foi realizada empregando a coluna Chiralcel OJ-H e metanol:etanol (50:50, v/v) + 0,2% de trietilamina como fase móvel. A vazão e temperatura utilizadas foram 0,8 mL min-1 e 25oC, respectivamente. Para extração dos analitos do meio de cultura, foi empregada a microextração em fase sólida (SPME) como técnica de preparação de amostra. O processo de SPME foi realizado utilizando uma fibra C18 mergulhando diretamente a fibra na amostra por 30 minutos e dessorvendo a fibra diretamente na fase móvel por 5 minutos. A validação e estudos de biotransformação foram realizados empregando a cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS). O método foi validado e todos os parâmetros encontram-se de acordo com as recomendações da literatura. O estudo de biotransformação foi realizado com diferentes espécies de fungos e somente os fungos do gênero Cunninghamella foram capazes de biotransformar a risperidona em seu metabólito ativo. O fungo Cunninghamella echinulata foi capaz de biotransformar estereosseletivamente a risperidona no seu metabólito ativo (+)-9-RispOH com excesso enantiomérico de 100% e o fungo Cunninghamella elegans foi também capaz de biotransformar estereosseletivamente a risperidona nos dois enantiômeros da 9-RispOH em diferentes proporções. Os estudos preliminares de catálise assimétrica foram realizados empregando a cromatografia líquida e detecção por UV-Vis, injetando diretamente alíquotas no sistema cromatográfico. Esses estudos mostraram que na condição de reação 1:50:50 (em número de mols, catalisador:oxidante:substrato) houve uma catálise assimétrica da risperidona que demonstrou ser enantiosseletiva para o metabólito 7-RispOH (E1). / Risperidone is an atypical antipsychotic drug. Its metabolism yields in two hydroxylated chiral metabolites, 7-hydroxyrisperidone (7-RispOH) and 9-hydroxyrisperidone (9-RispOH). The 9-RispOH metabolite presents the same pharmacologic activity of the parent drug risperidone. This led this drug to be marketed as drug under the generic name paliperidone. Studies have shown differences in the kinetic disposition of the 9-RispOH enantiomers with higher prevalence of the (+)-9-RispOH enantiomer in plasma. Thus, this work aimed to evaluate the ability of some species of fungi and Jacobsen catalysts in the enantioselective (bio)transformation of risperidone into its active chiral metabolite 9-RispOH. To accomplish that, it was developed a separation method to analyze risperidone and its metabolites by chiral high-performance liquid chromatography. This method was employed in enantioselective biotransformation studies and in asymmetric catalysis studies. The chromatographic separation was performed on a Chiralcel OJ-H column using methanol:ethanol (50:50, v/v) plus 0.2% triethylamine as the mobile phase at a flow rate of 0.8 mL min-1. The SPME process was performed by immersing directly a C18 probe fiber in the culture medium during 30 min. The analytes were desorbed from the fiber directly in the mobile phase during 5 min. The method validation and the biotransformation studies were performed by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The method was completely validated and all parameters were in agreement with the literature recommendations. The biotransformation studies were performed employing different species of fungi and only the Cunninghamella genus was able to biotransform risperidone into its active metabolite. The Cunninghamella echinulata fungus was able to biotransform risperidone into the active metabolite, (+)-9-RispOH, resulting in 100% of enantiomeric excess. The Cunninghamella elegans fungus was also able to biotransform stereoselectively risperidone into (+)- and ()-9-RispOH enantiomers at different rates. Preliminary studies of asymmetric catalysis were performed using high-performance liquid chromatography with UV-Vis detector (HPLC-UV). The aliquots were directly injected in the chromatography system. These studies showed that the reaction with 1:50:50 (catalyst:oxidant:substrate, in number of mols, in this sequence) presented an asymmetric catalysis of risperidone and that showed to be enantioselective to 7-RispOH (E1) metabolite.

Due to the high childhood obesity rates within the United States, it is necessary to develop efficacious strategies to combat childhood obesity. To explore whether early intervention can produce lasting metabolic improvements, we used a mouse model of genetically-induced hypothalamic leptin resistance (LeprNkx2.1knockout, hereby known as KO) that exhibits early-onset hyperphagia and obesity. We found that KO mice exhibit reduced capacity of the brown adipose tissue (as seen by disorganized mitochondrial structure). Brown adipose tissue capacity can be restored by paired-feeding in the peri-weaning period, leading to persistent improvements in later adiposity even after restriction ends. These studies lead us to investigate the maturation process of brown adipose tissue in the peri-weaning period. We found that brown adipose tissue expansion between 2 to 3 weeks of age is accompanied by a reduced thermogenic capacity in control mice, as determined by protein levels of uncoupling protein 1 and disorganization of the mitochondrial cristae. Thermogenic function was restored by 5 weeks of age, as demonstrated by a peak of uncoupling protein 1, in control mice but not KO mice. Paired-feeding of KO mice in the peri-weaning period rescued this peak at 5 weeks of age. These studies elucidate a critical period when brown adipose tissue expansion is followed by activation. The magnitude of brown adipose tissue activation at this time might be predictive of future obesity and metabolic rate, highlighting a potential therapeutic time window in which to intervene in pediatric obesity.

Orientadores: Gláucia Maria Pastore, Luiz Carlos Basso / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-10-02T14:43:34Z (GMT). No. of bitstreams: 1 Silva_JulianaBuenoDa_D.pdf: 2310696 bytes, checksum: 9ca677c093828e2fa9bdd9720ae5939c (MD5) Previous issue date: 2014 / Resumo: Os frutooligossacarídeos (FOS) são ingredientes de grande importância na indústria de alimentos e têm despertado muita atenção nos últimos anos por possuírem aplicações variadas e apresentarem propriedades prebióticas. O presente trabalho teve como objetivo avaliar a produção biotecnologica de FOS a partir de micro-organismos osmofílicos em um proceso de biotransformação utilizando células íntegras microbianas. As linhagens de Bacillus sp. e Aureobasidium sp, previamente isoladas de favo-de-mel e identificadas, foram primeiramente avaliadas quantos aos principais parâmetros de produção utilizando a metodologia de Superfície de Resposta, precisamente pelo Placket-Burman (PB), nos quais foram analisados 12 parâmetros para cada um dos microrganismos, dentre eles, a concentração da sacarose, inóculo, extrato de levedura, K2HPO4, (NH4)2SO4, MgSO4.7H2O, ZnSO4, MnSO4.7H2O, pH, temperatura e agitação. O Bacillus sp. apresentou 5 fatores significativos, sendo o pH, temperatura e agitação com efeitos negativos e o extrato de levedura e sulfato de amônia com efeitos positivos. Já o Aureobasidium sp. apresentou efeito positivo apenas para os parâmetros concentração de sacarose e sulfato de magnésio, sugerindo que o melaço de cana-de-açúcar, o qual era utilizado apenas para este microrganismo na etapa de cultivo do inóculo, poderia estar carreando nutrientes essenciais ao processo. A partir desta etapa, o trabalho teve continuidade apenas com a linhagem Aureobasidium sp. utilizando planejamentos experimentais sequenciais, a fim de se obter a faixa ótima de produção de FOS totais para esse processo. O estudo realizado para avaliar o efeito do melaço como meio de cultivo para o crescimento e obtenção do inóculo microbiano para o processo, demonstrou que a suplementação com nutrientes, avaliados na etapa do PB, era desnecessária, e o meio para síntese de FOS foi definido em apenas sacarose sem suplementação de nutrientes, com o inóculo na forma de suspensão celular cultivado previamente em meio a base de melaço. A produção neste momento atingia valores de 287,6 e 251,5 g/L de FOS totais e rendimentos de 72% e 63% em 24 e 48 horas respectivamente, com uma produtividade de 12 g/L.h às 24 horas de incubação. Em seguida foi realizado o planejamento fatorial fracionado para 4 variáveis definidas em tempo de cultivo e concentração do melaço, na etapa do cultivo do inóculo, e concentração de sacarose e de inóculo para a síntese de FOS, cujos apresentaram-se positivos com exceção ao tempo de cultivo que não demonstrou efeito nas condições avaliadas. Os valores de produção atingidos na etapa do fatorial foram de 333 g/L e 354 g/L de FOS totais e rendimentos de 60,5% e 64% em 24 e 48 horas respectivamente, e produtividade de 13,8 g/L.h às 24 horas de incubação. Após esses resultados, fixou-se a concentração do melaço em 10% de açúcares redutores totais, permanecendo apenas a concentração de sacarose e inóculo como variáveis para prosseguir o planejamento. A otimização desses dois fatores por Delineamento Composto Central Rotacional (DCCR), possibilitou definir 4 modelos significativos ao processo, atingindo faixas ótimas de produção para cada FOS como o GF2, GF3 e GF4, e revelou a condição ótima para o processo em 600 a 650 g/L de sacarose e de 20 a 23% de inóculo, resultando em uma produção de 351 e 374 g/L de FOS e rendimentos de 53,5% e 57% em 24 e 48 horas respectivamente, atingindo uma produtividade de 14,7 g/L.h às 24 horas de incubação. Após definida a condição ótima do processo, o xarope de cana-de-açúcar, que é o caldo concentrado, foi utilizado como substrato alternativo à substituição da sacarose pura na produção de FOS. Os valores de rendimentos obtidos foram de 54%, entretanto as concentração de FOS totais foram de 110 g/L uma vez que a concentração inicial de sacarose no xarope era de apenas 203 g/L. A maioria dos experimentos revelou que o micro-organismo manteve-se viável e em crescimento durante o período de incubação, de acordo com os valores de biomassa e atividade enzimática avaliados nos experimentos. Sendo assim, foi proposto avaliar o processo em um biorreator de bancada de 7L, cujo foi conduzido inicialmente em sistema de batelada e após as 48 horas o processo passou a ser contínuo com taxa de diluição de 0,04.h-1 por mais 72 horas, totalizando 120 horas de cultivo. A concentração média de FOS totais produzidos foi de 228 g/L e uma produtividade média foi de 9 g/L.h / Abstract: Fructooligosaccharides (FOS) are considered food ingredients with very significance for food industry that has receiving attention in the last few years, because of their functional properties for the health as prebiotics and industrial application. The objective of the present work was evaluate the biotechnological production of FOS by osmophilics microorganisms in a biotransformation process using free whole cells. Firstly the effects of production parameters using Bacillus sp. and Auerobasidium sp. strains. was employed by the Response Surface Methodology (RSM) exactly Plackett-Burman Design with 12 variables: concentration of sucrose, inoculum, yeast extract, K2HPO4, (NH4)2SO4, MgSO4.7H2O, ZnSO4, MnSO4.7H2O, pH, temperature and agitation. The Bacillus sp. showed 5 significant parameters, as pH, temperature and agitation with negative effect and yeast extract and ammonium sulfate with positive effect. The Aureobasidium sp. presents positive effect only for sucrose and magnesium sulfate concentration, which suggested the inoculum culture was caring nutrients from sugar cane molasses, that was the base of the inoculum cultivation for Aureobasidium sp. The work has continued only with Aureobasidum sp. applying sequential planning experiments to optimize the process. The experiment for evaluate the molasses effect as inoculum cultivation medium on process showed that nutrients supplementation, used in the PB design, wasn¿t necessary, consequently, the FOS synthesis medium was defined as sucrose, without nutrients supplements and the inoculum as cellular suspension previously cultivated in molasses medium. Total FOS data, at this point, reached 287.6 and 251.5 g/L with 72% and 63% of yield data at 24 and 48 hours respectively, with 12 g/L.h of productivity at 24 hours. Subsequently, the factorial planning was realized with 4 parameters as cultivation time and molasses concentration, in the inoculum cultivation step, and sucrose and inoculum concentration for the FOS synthesis. Almost all these factors showed positive effect, exception of inoculum cultivation time. The total FOS data, at this point, was 333 and 354 g/L with 60.5% and 64% of yield data at 24 and 48 hours respectively, with 13.8 g/L.h of productivity at 24 hours. Regarding these data, the molasses concentration was fixed at 10% of total reduce sugars, remaining only sucrose and inoculum concentration as variables to continue the planning. The two factors optimization was proceed by Central Composite Rotational Design (CCRD) that allowed defined 4 significant process model, aimed optimum production scales for which one FOS, as GF2, GF3 and GF4, that reveals the optimum process condition in 600 to 650 g/L of sucrose and 20 to 23% of inoculum, resulting in 351 and 354 g/L of total FOS data and 53.5% e 57% of yield data at 24 and 48 hours respectively, with 14.7 g/L.h of productivity at 24 hours. After defined the optimum process condition, the sugar cane syrup was evaluated as alternative substrate to pure sucrose for FOS production. The yield data reached was 54%, however the total FOS concentration was 110 g/L due to the small initial sucrose concentration on syrup that was 203 g/L. All the experiments showed significant microorganism growth and increase enzyme activity during the process. For this reason, the process was conducted in a 7L bioreactor, using initially batch system and after 48 hours the system was changed to continuous process with 0.04. h-1 for more 72 hours, with 120 total hours process. Data values showed the 9 g/L.h of productivity and 228 g/L of total FOS concentration / Doutorado / Ciência de Alimentos / Doutora em Ciência de Alimentos