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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Destoxifica??o do farelo de mamona (Ricinus Communis L.) por extrus?o termopl?stica / Detoxification of castor oil (Ricinus communis L.) Thermoplastic Extrusion

Silva, B?rbara Amorim 25 February 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-04T16:19:04Z No. of bitstreams: 1 2011 - B?rbara Amorim Silva.pdf: 5390134 bytes, checksum: 32ec2143250d4b2b5d5a8de98ea88d9d (MD5) / Made available in DSpace on 2016-10-04T16:19:04Z (GMT). No. of bitstreams: 1 2011 - B?rbara Amorim Silva.pdf: 5390134 bytes, checksum: 32ec2143250d4b2b5d5a8de98ea88d9d (MD5) Previous issue date: 2011-02-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The castor bean (Ricinus communis L) is a plant family Euphorbiaceae. Considered an oil of high economic value because this has a clearly defined market for the oil extracted from its seeds. The cake, which is a residue of this extraction, stands out for its high protein content. Among the proteins found in the cake stands ricin, a cytotoxin, which not allows its use as an alternative protein source for animal feed. In this study was used the extrusion-cooking technology, combined application of calcium hydroxide Ca(OH)2 in order to inactivate the protein fraction containing ricin. The extrusion process of cake castor oil was carried out using a Brabender DS20 cannon short. Was used the response surface methodology to investigate the effect of the interaction of parameters in the study. Was used a central composite design in order to evaluate the moisture effects (14%, 16%, 18%, 20%, and 21%), temperature (116?C, 130?C, 150?C, 170?C and 180?C) and concentration of Ca(OH)2.. As a comparative sample was used castor beans which were crushed to extract oil and cake which used as a sample without heat treatment, as standard. For the evaluation of physical-chemical, it was utilized methods of AOAC. The quantification of proteins was realized using the method of Bradford and the protein profile was electrophoresis-SDS-PAGE. Was used to mark the Biorad electrophoresis the methodology observed using the of preparation of the gels described by LaemmLi (1970). The results indicated that most of the different treatments performed totally changed the structure of ricin. Indizatily the possibility of total hydr?lise of this macromolecule. The application of extracts of castor oil in the gel electrophoresis allowed the observation of a clear chain A (RTA) and 38 kDa molecular weight B (RTB) molecular weight 36kDa. For the crude protein extract of bran molar mass chains A and B were approximately 37 kDa and 35 kDa respectively. The levels of protein extracted from the bran decreased 89% after extrusion. The results indicated that all treatments changed entirely the structure of ricin with the possibility of their having been a total hydrolysis of the polymer. According to tests performed and observed results, we conclude that the thermoplastic extrusion process is a suitable technology to decrease the activity of ricin / A mamoneira (Ricinus communis L.) ? uma planta da fam?lia Euforbi?cea que vem sendo muito estudada como fonte alternativa na produ??o de biodisel. O farelo, res?duo gerado ap?s a extra??o do ?leo da semente utilizando solvente, apresenta alto teor de prote?nas. Dentre as prote?nas encontradas na torta destaca-se a ricina, uma citotoxina, que inviabiliza sua utiliza??o como fonte prot?ica alternativa para alimenta??o animal. No presente estudo empregamos a extrus?o termopl?stica, associada ? aplica??o de hidr?xido de c?lcio Ca (OH)2 com o objetivo de inativar a fra??o prot?ica que contem a ricina. O processo de extrus?o do farelo de mamona foi realizado utilizando uma extrusora BRABENDER DS20 de canh?o curto. Utilizou-se a metodologia de superf?cie de resposta para verificar o efeito da intera??o dos par?metros estabelecidos no estudo. Foi utilizado um delineamento composto central rotacional a fim de avaliar os efeitos dos n?veis de umidade (14%, 16%, 20% e 21%), temperatura (116?C, 130?C, 150?C, 170?C e 180?C) e concentra??o Ca(OH)2.. Como amostra comparativa foi utilizada sementes de mamona da cultivar Paragua?? as quais foram esmagadas em prensa expeller at? extrair o ?leo e cuja torta foi utilizada como padr?o por apresentar maior integridade das cadeias polipept?dicas. Para a avalia??o das caracter?sticas f?sico-qu?micas, foram utilizados m?todos da AOAC, para quantifica??o de prote?nas foi utilizado o m?todo de Bradford e para avalia??o do perfil prot?ico foi utilizada a eletroforese- SDS-PAGE, atrav?s do sistema de eletroforese da marca Biorad com a metodologia de prepara??o dos g?is descrita por Laemmli (1970). Os m?todos de purifica??o usando a di?lise e precipita??o com sulfato de am?nio favoreceu para um bom rendimento quanto ao teor de prote?na, principalmente a ricina. A aplica??o dos extratos da torta de mamona no gel de eletroforese permitiu a observa??o n?tida das cadeias A (RTA) massa molar 38 kDa e B (RTB) massa molar 36kDa. Para o extrato prot?ico do farelo bruto a massa molar das cadeias A e B ficaram em torno 37 kDa e 35 kDa respectivamente. Os n?veis de prote?na extra?da do farelo diminu?ram 89% ap?s a extrus?o. Os resultados indicaram que todos os tratamentos realizados modificaram totalmente a estrutura da ricina, com possibilidade de ter havido hidr?lise total desta macromol?cula. De acordo com os ensaios realizados e resultados observados, conclui-se que o processo de extrus?o termopl?stica ? uma tecnologia adequada para diminuir a atividade da ricina. Palavras-chave: Citotoxina, Eletroforese
2

Caracter?sticas bioativas, funcionais e efeito protetor do res?duo desidratado de camu-camu (Myrciaria dubia H.B.K. (McVaugh)) sobre doen?as degenerativas utilizando modelos in vivo C. elegans / Bioactive, functional and neuroprotective effects of dried camu-camu (Myrciaria dubia H.B.K. (McVaugh)) pomace using the in vivo model C. elegans

Azevedo, Juliana Chris Silva de 27 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-22T00:26:39Z No. of bitstreams: 1 JulianaChrisSilvaDeAzevedo_TESE.pdf: 3335761 bytes, checksum: 5840f8f561d3f40aa1c1d8a4d26f2dce (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-22T23:34:50Z (GMT) No. of bitstreams: 1 JulianaChrisSilvaDeAzevedo_TESE.pdf: 3335761 bytes, checksum: 5840f8f561d3f40aa1c1d8a4d26f2dce (MD5) / Made available in DSpace on 2016-03-22T23:34:50Z (GMT). No. of bitstreams: 1 JulianaChrisSilvaDeAzevedo_TESE.pdf: 3335761 bytes, checksum: 5840f8f561d3f40aa1c1d8a4d26f2dce (MD5) Previous issue date: 2015-02-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / O camu-camu (Myrciaria dubia H.B.K. (McVaugh)) ? um fruto nativo da Regi?o Amaz?nica, que se tornou mundialmente conhecido por seu alto teor de ?cido asc?rbico. Devido a seu elevado grau de acidez, o fruto ? consumido principalmente como suco ou utilizado como ingrediente na prepara??o de alimentos. Dessa maneira, durante seu processamento s?o geradas quantidades consider?veis de res?duo agroindustrial. Apesar de estudos que apontam sua riqueza em compostos bioativos e efeitos biol?gicos, poucas s?o as informa??es sobre t?cnicas de transforma??o, aproveitamento e preserva??o dos frutos e de seu res?duo industrial, as quais poderiam ser empregadas em prol de sua utiliza??o funcional. Sendo assim, o presente trabalho teve como objetivo avaliar a aplica??o de dois processos de secagem, por convec??o em secador de bandejas e por liofiliza??o sobre o res?duo de camu-camu (constitu?do por casca e sementes com polpa aderida), visando obter um produto com qualidades funcionais. A presente tese foi dividida em tr?s etapas: a primeira etapa mostra os estudos relacionados ? secagem convectiva e liofiliza??o, na qual foi avaliado o impacto de ambos os processos sobre compostos bioativos selecionados, tomando o res?duo fresco como amostra controle. Dentre as condi??es estudadas, os grupos obtidos por convec??o a 50?C e 4 m/ s (SC50) e 80?C e 6 m/ s (SC80) apresentaram melhor combina??o de concentra??o de ?cido asc?rbico, capacidade redutora do Folin-Ciocalteau e caroten?ides totais, e foram selecionados para estudos complementares. Al?m disso, o res?duo liofilizado (RL) e o res?duo fresco (RF) foram investigados nas etapas posteriores da pesquisa. De maneira geral, foi observada maior concentra??o dos constituintes bioativos no grupo RF, seguido do RL e, por fim, os res?duos desidratados por convec??o, SC50 e SC80, respectivamente. Na segunda etapa, foram avaliadas atividades antioxidante, microbiol?gica e antienzim?tica, onde tamb?m foi observada a mesma tend?ncia nos resultados. Nessa etapa, foi identificada, pela primeira vez na literatura, a presen?a do ?cido sir?ngico no res?duo do camu-camu. A terceira parte desta tese abordou a investiga??o dos efeitos do res?duo de camu-camu desidratado sobre o envelhecimento e doen?as neurodegenerativas, utilizando o modelo in vivo C. elegans. Os extratos de camu-camu foram capazes de favorecer genes importantes das vias de ativa??o/inibi??o do estresse oxidativo e t?rmico (p < 0,05). Para o verme do tipo selvagem N2, as fra??es do extrato de baixo peso molecular PA (fase aquosa e polar ?cida), PB (fase aquosa e polar b?sica) e PN (fase org?nica e polar neutra) do grupo SC50 estenderam o tempo de vida em 20% e 13% (p < 0,001). Os resultados obtidos revelaram que a paralisia induzida pelo pept?deo Amil?ide ?1-42 associada a doen?a de Alzheimer, foi retardada significativamente (p < 0,0001) na linhagem CL4176. Da mesma forma, os extratos de camu-camu foram capazes de atenuar a indu??o dopamin?rgica associada ao mal de Parkinson. Finalmente, a an?lise global dos dados mostra que o res?duo de camucamu, co-produto obtido a partir de uma fruta nativa Brasileira, constitui uma fonte natural de compostos relevantes para a sa?de humana. Dessa forma, a presente tese mostra de maneira in?dita a multifuncionalidade desse produto ainda subaproveitado do ponto de vista cient?fico, comercial e tecnol?gico. / Camu-camu (Myrciaria dubia H.B.K. (McVaugh)) is a native Amazon fruit, recognized worldwide as one of the main natural sources of ascorbic acid. Due to its great acidity, this fruit is generally consumed after processing into juice or as ingredient in food preparations. As a co-product of the camu-camu processing, a significant amount of agroindustrial residue is generated. Despite the studies showing the bioactive value and biological potential of the fruit, few studies have approached the possible processing techniques, transformation and preservation of camu-camu fruits and its agroindustrial pomace. Therefore, the present work has the objective of evaluating two different drying processes applied to camu-camu pomace (peel and seeds with residual pulp), freeze drying and hot air drying, in order to obtain a functional fruit product. This thesis was divided into three stages: the first one shows the studies related to the freeze drying and hot air drying, where we demonstrated the impact of the selected drying techniques on the bioactive components of camu-camu, taking the fresh pomace as the control group. Among the investigated conditions, the groups obtained at 50?C and 4 m/s (SC50) and 80?C and 6 m/s (SC80) were selected as for further studies, based on their ascorbic acid final content and Folin-Ciocalteau reducing capacity. In addition to SC50 and SC80, the fresh pomace (RF) and freeze dried (RL) samples were also evaluated in these further stages of the research. Overall, the results show higher bioactive concentration in the RF samples, followed by RL, SC50 and SC80. On the second step of the research, the antioxidant, antimicrobial and antienzymatic activities were evaluated and the same tendency was observed. It was also reported, for the first time in the literature, the presence of syringic acid in dried camu-camu pomace. In the third and final stage of the research, it was investigated the effect of dried camu-camu on aging and neuroprotective disorders, using the in vivo model C.elegans. It was observed that camu-camu extracts were able to modulate important signaling genes relevant to thermal and oxidative stresses (p < 0.05). The polar acid, polar basic and polar neutral fractions obtained from the low molecular extracts of SC50 were able to extend the lifespan of wild type N2 C. elegans in 20% and 13% (p < 0.001). Results also showed that the paralysis induced by the ?1-42 amyloid was significantly (p < 0.0001) retarded in CL4176 worms. Similarly, the camu-camu extracts attenuated the dopaminergic induction associated to Parkinson?s disease. Finally, a global analysis of the data presented here reveal that the camu-camu pomace, a co-product obtained from the industrial processing of a native Brazilian fruit, is a relevant natural source of health relevant compounds. This thesis, shows for the first time, the multifunctionality of camu-camu pomace, a natural resource still underexploited for scientific, commercial and technological purposes.
3

Secagem do res?duo de acerola (Malphigia emarginata D.C.): estudo do processo e avalia??o do impacto sobre o produto final / Secagem do res?duo de acerola (Malphigia emarginata D.C.): estudo do processo e avalia??o do impacto sobre o produto final

N?brega, Erly Maria Medeiros de Ara?jo 30 March 2012 (has links)
Made available in DSpace on 2014-12-17T15:01:29Z (GMT). No. of bitstreams: 1 ErlyMMAN_DISSERT.pdf: 2763165 bytes, checksum: 02d0a064f93f95db42ddc7fc2c52410e (MD5) Previous issue date: 2012-03-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Brazil, one of the largest agricultural producers in the world, has managed in recent years to significantly improve its production. However, in response to this advance in the agro-industrial sector, the generation of agro-industrial residues has also increased. New technological alternatives have to be implemented in order to bring economic and rational use of this material and drying is one of the possible choices. Considering the great importance that bioactive compounds present for food science and technology, this research aims to evaluate the air-drying process of acerola residue in a tray convective drier under controlled temperature (60, 70 e 80?C), air velocity (4.0, 5.0 e 6.0 m/s) and material width (0.5, 0.62 e 0.75 cm) by applying an experimental planning 23 + 3. Based on that, the impact on physical-chemical characteristics, color, bioactive compounds concentration and antioxidant activity of dried acerola waste was evaluated, having the in natura and freeze dried waste as control groups. Dried acerola residue presented natural pigments, mainly carotenoids (143.68 - 68.29 mg/g) and anthocyanins (290.92 - 90.11 mg/100 g), which explain the red and yellow instrumental color parameters observed. The acerola residue powder is also rich in phenolic compounds (3261.11 -2692.60 mgGAEeq/100g), proanthocyanidins (61.33-58.46 eq/100g), ascorbic acid (389.44 739.29 mg/100 g) and DPPH antioxidant activity (20.91 24.72 ?g Trolox eq/g). Results show decreased concentration of phenolic compounds, anthocyanins, carotenoids, proanthocyanidins and ascorbic acid caused by the air-drying process. However, even after the observed drying losses, the acerola residue powder can be considered a high value food ingredient, considering the high bioactive compounds concentration found in the final product, as well as the colorimetric characterization and microbiological stability of the dried powder / O Brasil, um dos maiores produtores agr?colas atuais, tem conseguido aumentar sua produ??o agroindustrial nos ?ltimos anos. Em conseq??ncia a isso a gera??o de res?duos tamb?m aumentou. Dessa forma, torna-se relevante a pesquisa de alternativas de uso racional e econ?mico para esse tipo de mat?ria prima, incluindo opera??es unit?rias de transforma??o como a secagem. Diante da import?ncia que os compostos bioativos apresentam para a ?rea de ci?ncia e tecnologia de alimentos, esta pesquisa objetivou avaliar a secagem do res?duo agroindustrial da acerola em secador convectivo de bandejas sob condi??es controladas de temperatura de trabalho (60; 70 e 80?C), velocidade do ar (4,0; 5,0 e 6,0 m/s) e espessura do material (0,5; 0,62 e 0,75 cm), mediante aplica??o de planejamento experimental do tipo fatorial 23 + 3 pontos centrais. A partir disso, o impacto da secagem sobre as caracter?sticas f?sico-qu?micas, cor, concentra??o de compostos bioativos selecionados e atividade antioxidante do res?duo da acerola s?o abordados, tomando os res?duos in natura e liofilizado como grupos-controle. Os p?s do res?duo desidratado de acerola apresentaram presen?a de pigmentos naturais, com colora??o vermelha e amarela, sobretudo caroten?ides (143,68 a 68,29 mg/g), antocianinas (290,92 a 90,11 mg/100 g), al?m de elevado teor de compostos fen?licos (3261,11 a 2692,60 mg GAE eq/100 g amostra), proantocianidinas (61,33 a 58,46 eq/100 g amostra) e ?cido asc?rbico (389,44 a 739,29 mg/100 g), bem como expressiva atividade antioxidante obtida pelo m?todo DPPH (20,91 a 24,72 ?g Trolox eq/g amostra). Os dados experimentais mostraram diminui??o da concentra??o de compostos fen?licos, antocianinas, caroten?ides, proantocianidinas e ?cido asc?rbico ocasionada pela secagem nas condi??es estudadas. No entanto, a concentra??o final desses compostos detectada no produto desidratado, bem como a caracteriza??o colorim?trica e a estabilidade microbiol?gica alcan?ada, caracteriza o p? do res?duo de acerola como ingrediente com elevado potencial bioativo

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