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Strontium apatite nanoparticle bioactive bone cement: from biomaterial development to pre-clinicalevaluationsLam, Wing-moon, Raymond., 林榮滿. January 2009 (has links)
published_or_final_version / Orthopaedics and Traumatology / Doctoral / Doctor of Philosophy
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Composition and functional bioactive properties of bambara groundnut protein and hydrolysatesArise, Abimbola Kemisola January 2016 (has links)
Submitted in complete fulfillment for the degree of Doctor of Philosophy (Food Science and Technology), Durban University of Technology, Durban, South Africa, 2016. / Bambara groundnut (Vigna substerranea) is an indigenous legume of African origin which is currently experiencing a low level utilisation. It is tolerant to drought and can grow under poor soil conditions in which other lucrative crops such as groundnut cannot grow. Bambara is a good source of protein comparable to that of cowpea and slightly lower than soya bean. In order to assess the potential use of bambara protein as a functional ingredient in food systems and as an important ingredient for the formulation of therapeutic product, the knowledge of its protein composition, structure and functionality becomes important.
The main goal of this thesis was to determine the composition and bioactive properties of bambara protein and its hydrolysates. Specifically, a comparative study was carried out on the protein content, yield and functional properties of protein concentrates prepared from three different bambara landraces using different extraction methods (Salt solubilisation and Acid precipitation). There was no significant difference in protein content, yield and functional properties of the landraces. However, the method of extraction had an influence on their physicochemical and functional properties. Acid precipitation produced bambara protein concentrates with high protein content and yield (79% and 52% respectively) when compared to salt solubilisation (protein content - 57% and yield - 25%). Protein concentrates prepared through salt solubilisation method exhibited better functional properties in terms of water absorption capacity, oil absorption capacity, foaming capacity, foaming stability and emulsion activities when compared to concentrates obtained through acid precipitation.
Furthermore, the composition of bambara proteins produced through isoelectric precipitation was determined. SDS PAGE revealed four major bands; a broad band at 55 kDa which was analysed to be vicilin, two medium bands at 62 kDa and 80 kDa and a high molecular weight (HMW) protein at 141 kDa. Further investigation of bambara protein revealed vicilin (55 kDa) with two sub units as the major protein in bambara and this was also confirmed by the proteomic map. The proteomic map revealed acidic amino acids as the major protein of bambara which is characteristic of vicilin, the map also showed that there were differences in the number of spots across the landraces with 77 spots matching each other. Circular dichroism spectroscopy exhibited reductions in α-helix, and β-pleated sheet conformations as pH varies. In addition, the tertiary structures as observed from the near-UV CD spectra were also influenced by shifts in pH conditions. Differential scanning calorimetry thermograms showed two endothermic peaks at around 67 and 81oC respectively. These can be attributed to thermal denaturation of vicilin and the HMW protein. Subsequent studies used isolates from red bambara since the composition of the landraces were similar.
Bambara protein isolate was subjected to enzymatic hydrolysis using three proteases (alcalase, pepsin and trypsin) to produce various bambara protein hydrolysates (BPHs). BPHs were investigated for antioxidant and antihypertensive activities. The in vitro structural and functional characteristics of bambara protein and its enzymatic protein hydrolysate revealed that bambara groundnut possessed antioxidant properties against a variety of physiologically relevant free radicals. High surface hydrophobicity and the molecular size of the peptide seem to be important for scavenging of hydroxyl radicals, ferric reducing power and metal chelation. BPHs and peptide fractions were able to scavenge DPPH radicals with greater affinity for smaller size. Less than 1 and 1-3 kDa pepsin fraction was able to scavenge DPPH radical more than glutathione, BPHs and its fractions scavenge ABTS•+ three folds than the isolate. Scavenging of superoxide radicals was generally weak except for 5-10 kDa peptide fractions. All BPHs inhibited linolenic acid oxidation with greater affinity for the lower molecular size peptide.
BPHs showed potential antihypertensive properties because of the in vitro inhibition of activities of angiotensin converting enzyme (ACE) and renin inhibition. The molecular size had significant effect on the ACE inhibitory properties with low molecular weight peptide (<1 kDa) fractions exhibiting significantly higher (p<0.05) inhibitory activities. However, enzyme type had synergistic effects on renin inhibition with alcalase hydrolysate showing highest inhibition at 59% when compared to other hydrolysates and their membrane fractions. The fractions with <1 and 1-3 kDa peptides showed a higher potential as antihypertensive and antioxidant peptides. Based on this study, incorporation of bambara protein isolate as an ingredient may be useful for the manufacture of high quality food products. Likewise, the bambara protein hydrolysates, especially the <1 kDa and 1-3 kDa fraction represent a potential source of bioactive peptides in formulating functional foods and nutraceuticals. / D
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Bioactive compounds from South African plants against Mycobacterium tuberculosisSingh, Alveera January 2016 (has links)
Submitted in fulfillment for the Degree of Doctor of Philosophy (Biotechnology), Durban University of Technology, Durban, South Africa, 2016. / Mycobacterium tuberculosis (MTB), the causative agent of tuberculosis (TB) has infected approximately one-third of the world population, with 9.6 million TB cases in 2014. The emergence of multi-drug resistant (MDR) and extensively-drug resistant (XDR) strains of MTB has further complicated the problem of TB control. It is now imperative that novel antimycobacterial compounds are discovered in order to treat infections and reduce the duration of current TB therapy courses. For centuries, medicinal plants have been used globally worldwide for the treatment and prevention of various ailments. This occurs particularly in developing countries where infectious diseases are endemic and modern health facilities and services are inadequate. In recent years, the use and search for plant drug derivatives have been fast-tracked. Ethnopharmacologists, botanists, microbiologists, and natural product chemists are trying to discover phytochemicals which could be developed for the treatment of infectious diseases, especially TB. Plants are rich in a wide variety of secondary metabolites, such as tannins, terpenoids, alkaloids, and flavonoids, which have been found in vitro to have antimycobacterial activity.
In the search for new lead compounds, nine medicinal plant species, Buddleja saligna, Capparis tomentosa, Carpobrotus dimidiatus, Dichrostachys cinerea, Ekerbergia capensis, Ficus Sur, Gunnera perpensa, Leonotis leonurus and Tetradenia riparia were collected in Kwa-Zulu Natal (KZN) following report of their therapeutic use in traditional medicine to treat symptoms and infections related to TB. They were tested in vitro for their activity against Mycobacterium smegmatis, Mycobacterium tuberculosis H37Rv (ATCC 25177) and three well-characterized clinical isolates of MDR-TB and XDR-TB using the agar incorporation method. The minimum inhibitory concentration of the active plant extracts was determined using the broth microdilution method. Our findings show that five of the nine plants screened have antimycobacterial activity with concentrations ranging from 125 µg/ml to 1000 µg/ml.
The aqueous extracts of G. perpensa and T. riparia; and the methanolic extracts of B. saligna, C. tomentosa, and C. dimidiatus possessed significant activity against M. smegmatis, M. tuberculosis H37Rv (ATCC 25177) and the three well-characterized clinical isolates of MDR-TB and XDR-TB.
The cytotoxic effect of the active plant extracts was evaluated against the mouse BALB/C monocyte-macrophage (J774.2) and peripheral blood mononuclear cells (PBMCs). The toxic effects of the active plant extracts were evaluated using the brine shrimp lethality assay. Except for a high concentration of G. perpensa none of the other plants which possessed antimycobacterial activity showed any toxic or cytotoxic activity. The active plant extracts were thereafter assessed to determine if they had any effect on the survival or death of mycobacterial species, M. smegmatis, bound within the macrophage (J774.2) cell line at a concentration of 100 µg/ml. B. saligna had inactivated most of the phagocytosed bacilli after 24 hours of treatment therefore, it has a bactericidal effect on the mycobacteria located within the mouse macrophage.
A phytochemical investigation of the leaves of B. saligna led to the isolation of two isomeric pentacyclic triterpene compounds namely Oleanolic Acid (OA) and Ursolic Acid (UA) using thin layer chromatography followed by silica gel column chromatography. The structures of these compounds were fully characterized by detailed NMR investigations, which included 1H and 13C NMR. Ursolic acid was isolated from this plant for the first time. Two-dimensional (2D) and three-dimensional (3D) quantitative structure-activity relationship (QSAR) studies were carried out to provide insight on the interaction of the compounds with the enzyme. Molecular docking studies predicted the free binding energy of the triterpenes inside the steroid binding pocket of Mycobacterium tuberculosis fadA5 thiolase compared to a reported inhibitor. Thus, their ability to inhibit the growth of Mycobacterium tuberculosis was predicted and was confirmed to possess significant antimycobacterial activity when tested against M. smegmatis, M. tuberculosis H37Rv (ATCC 25177), clinical isolates of MDR-TB and XDR-TB using the Microplate Alamar Blue Plate (MABA) assay.
The present study has scientifically validated the traditional use of medicinal plant B. saligna. / D
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A novel bioactive glass-enhanced orthodontic bonding resin: A shear bond strength studyJohnson, Cole 03 May 2011 (has links)
Enamel decalcification caused by poor oral hygiene is a significant problem in orthodontics. Bioactive glass-containing resins have been shown to release Ca2+ ions into surrounding solution. The purpose of this study was to determine the shear bond strength of four different compositions of orthodontic resin prepared with bioactive glass (N=20). Premolars were bonded using one of four BAG-BOND compositions. Brackets were debonded and ARI scores were given. The mean shear bond strength was 7.23 ± 2.47 MPa (62 BAG-BOND), 8.25 ± 2.87 MPa (65 BAG-BOND), 8.78 ± 3.08 MPa (81BAG-BOND) and 5.80 ± 2.27 MPa (85 BAG-BOND). 65 and 81 BAG-BOND were significantly higher than 85 BAG-BOND. The 62 BAG-BOND group was not statistically significantly different from any other group. All groups exhibited a cohesive bond failure and were not statistically significant from each other. Three compositions of the novel orthodontic adhesive exhibited adequate bond strength for clinical applications.
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Leishmanioses e derivados de furoxano e benzofuroxano : atividade biológica in vitro e in vivo e potenciais mecanismos de ação /Almeida, Letícia de. January 2017 (has links)
Orientadora: Marcia Aparecida Silva Graminha / Banca: Jean Leandro dos Santos / Banca: Maria José Soares Mendes Giannini / Banca: Sergio de Albuquerque / Banca: André Luiz Pedrosa / Resumo: As leishmanioses são doenças causadas pelo protozoário parasito do gênero Leishmania e transmitidas pela picada do insetor vetor, o flebotomíneo. As leishmanioses apresentam diferentes manifestações clínicas, sendo elas leishmaniose cutânea, mucocutânea, cutânea difusa e visceral. Os fármacos atualmente disponíveis para o tratamento das leishmanioses apresentam diversos efeitos colaterais, além de problemas associados às vias de administração e surgimento de cepas resistentes. Os furoxanos e benzofuroxanos são compostos heterocíclicos contendo a função N-óxido com múltiplas atividades, incluindo anti-T. cruzi e anti-Leishmania. Neste trabalho, uma série de derivados de furoxano (compostos 3, 4a-b, 13a-b, e 14a-f) e benzofuroxano (7 e 8a-c) foram avaliados em ensaios in vitro frente as espécies L. (L.) amazonensis, L. (L.) mexicana e L. (L.) infantum. Os compostos foram também avaliados quanto à citotoxicidade em macrófagos murinos e quanto à sua capacidade de produção de óxido nítrico in vitro e em macrófagos infectados com o parasito. A atividade leishmanicida (EC50) dos derivados em estudo variou de 2,0 a 96,0 µM, enquanto que a citotoxicidade de 5,0 a 250,0 µM. A molécula doadora de óxido nítrico 14e revelou ser a mais promissora dentre os derivados analisados, exibindo ação pH-dependente. Adicionalmente, o derivado 14e mostrou ser capaz de inibir a enzima cisteíno protease de Leishmania, importante fator de virulência deste parasito. Estes ensaios mostraram que 14e inibe ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Leishmaniases are diseases caused by the protozoan parasite of Leishmania genus and transmitted by the bite of insect vetor, phlebotomine. Leishmaniases present different clinical manifestations, including cutaneous, mucocutaneous, diffuse cutaneous and visceral leishmaniasis. The currently available drugs for leishmaniasis treatment show several side effects, besides problems associated with the administration routes and the emergence of resistant strains. Furoxan and benzofuroxan are heterocyclic compounds containing the N-oxide function showing several activities, including anti-T. cruzi and antiLeishmania. In this work, a series of furoxan (compounds 3, 4a-b, 13a-b, and 14a-f) and benzofuroxan (7 and 8a-c) derivatives were tested against the species L. (L.) amazonensis, L. (L.) mexicana e L. (L.) infantum. The compounds were also evaluated for cytotoxicity against murine macrophages and as to its ability to produce nitric oxide in vitro and in macrophages infected with the parasite. The antileishmanial activity (EC50) of the derivatives studied ranged from 2.0 to 96.0 μM, whereas the cytotoxicity of 5.0 to 250.0 μM. The nitric oxide donor molecule 14e revealed to be the most promising of the analyzed derivatives, exhibiting a pH-dependent action. Futhermore, the derivative 14e was shown to be capable of inhibiting the cysteine protease enzyme of Leishmania, an important virulence factor of this parasite. These assays showed that 14e inhibits the cysteine protease B 2.8 re... (Complete abstract click electronic access below) / Doutor
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Organoteluretos na preparação de substâncias bioativas / Organotellurides in the preparation of Bioactive compoundsPrincival, Jefferson Luiz 02 June 2010 (has links)
O presente trabalho teve como foco principal, a preparação one pot de compostos orgânicos alquílicos e vinílicos contendo o grupamento butiltelurenila em sua estrutura, e o estudo do comportamento desses em variados tipos de reações. Uma delas foi a reação de troca Te/Li. Assim, teluretos foram utilizados como equivalentes sintéticos de vários reagentes organometálicos. Os teluretos foram submetidos à reação de troca Te/Li, e os respectivos compostos organolítio gerados, transformados em reagentes organometálicos de zinco, cobre e cério através de reações de transmetalação. Esses reagentes gerados in situ foram submetidos à reação com variados eletrófilos. Os reagentes organometálicos de zinco e cobre gerados foram submetidos à reação de acilação frente a cloreto de ácidos, resultando em 1,4-hidroxicetonas. Um exemplo dessas hidroxicetonas foi obtido em sua forma enantiopura utilizando um telureto quiral, e esse utilizado na síntese formal e enantiosseletiva da (-)-Pirenoforina. Diferentes estequiometrias de cupratos e outros reagentes organometálicos oriundos de um telureto também foram preparados, e esses testados em reações de substituição de tosilatos e abertura de epóxidos. Os substratos gerados dessas reações foram empregados na síntese das moléculas bioativas Endo-Brevicomina e Frontalina. Apresentaremos também, o resultado obtido na reação direta entre uma espécie di-litiada quiral na presença de benzonitrila. A hidroxicetona assim produzida é um análogo do Ipomeanol, um composto com atividade contra câncer de pulmão. Será apresentado também, o comportamento de entidades di-aniônicas contendo grupamentos silila em reações catalisadas por CeCl3, em que a captura desses com eletrófilos como aldeídos, forneceram 1,4-enedióis em bons rendimentos químicos e alta diastereosseletividade. Será apresentado também o estudo do comportamento de teluretos com hibridização sp2 em reações pericíclicas. A reação pericíclica estudada compreende compostos contendo telúrio (II) e (IV) em reações de Diels-Alder. / One of the main purposes of this work was to develop a new direct methodology to prepare functionalized organic tellurides, to be submitted to a series of different reactions, as for example the Te/Li exchange reaction, aimed to afford synthetic equivalents of several organometallic reagents. Zinc, copper and cerium organometallic compounds were generated via a transmetalation reaction of the lithium species, and were reacted with several electrophiles. As a result, 1,4-hydroxyketones could be successfully prepared. According to this methodology, an enantioenriched 1,4-hydroxyketone could be obtained, using a chiral telluride as starting material. This chiral nonracemic intermediate was employed in an enantioselective formal synthesis of (-)-Pyrenophorin. Cuprates and other organometallic reagents, prepared from a specific telluride and using the above described methodology, were the choosen nucleophiles for performing some aliphatic substitution reactions and, in particular, for the ring opening of epoxides. The resulting products were employed as building blocks for the synthesis of the bioactive cyclic compounds Endo-Brevicomin and Frontalin. The direct reaction of the chiral dilithiated specie with benzonitrile afforded a 1,4-hydroxyketone as an analogue of Ipomeanol, a bioactive compound for cancer therapy. Bis-anionic sililated species, prepared from a telluride, were submitted to reaction with a series of aldehydes. Such reactions, in which CeCl3 was employed as catalyst, showed to be highly diastereoselectives, affording (E)-1,4-enediols in good yields. The pericyclic reaction of insaturated tellurides was also investigated. It is worth mentioning that the same Diels-Alder reaction could be performed either with tellurium II or tellurium IV species.
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Interação biológica de membranas poliméricas bioativas em falhas ósseas induzidas em tíbias de coelhos / Biological interaction of polymeric bioactive membranes in rabbit tibial defectsCunha, Olicies da 29 May 2012 (has links)
O reparo de falhas ósseas tem sido motivo de preocupação e estudos em ortopedia. O enxerto esponjoso autógeno é consagrado e definido como padrão ouro, porém, o leito doador é limitado e a colheita pode causar grande morbidade. Tem sido proposto, ao longo dos anos, o uso de materiais naturais, sintéticos e fatores de crescimento com resultados promissores. O desenvolvimento de membranas e matrizes tridimensionais, baseado em biomateriais reabsorvíveis e biocompatíveis, tem demandado estudos voltados à síntese e avaliação. O objetivo do estudo foi avaliar o processo de reparação óssea por meio do uso de três polímeros bioativos em falhas ósseas em tíbias de coelhos. Foram estudados 48 coelhos machos, adultos jovens, distribuídos em quatro tempos experimentais (três, sete, 14 e 30 dias). Cada tíbia constituiu uma unidade experimental, de modo que foram confeccionados dois defeitos ósseos monocorticais em região proximal medial de cada tíbia. Cada tempo experimental contemplou quatro grupos: controle - sem adição de biomaterial; M1 - orifícios protegidos com Poli L Lactide co Policaprolactone / Poli Glicol Etilênico; M2 - Poli L Lactide co Policaprolactone / Poli Glicol Etilênico / Fosfato Tricálcico e M3 - Poli L Lactide co Policaprolactone / Poli Glicol Etilênico / nano Hidroxiapatita. Ao final de cada período os indivíduos foram submetidos à eutanásia e obtidos cortes histológicos das tíbias, corados com técnica de HE, TRAP e Masson. Foram feitas análises histomorfológicas descritivas e histomorfométricas, com mensuração do tecido ósseo neoformado, porcentagem da área de trabéculas ósseas, número de osteoclastos e porcentagem de trabéculas ósseas com osteoclastos. Os dados foram submetidos aos testes de Kruskal-Wallis e Mann-Whitney. Os resultados mostraram absorção incompleta da membrana e ausência de toxicidade. Para os períodos de 14 e 30 dias, o grupo controle exibiu matriz óssea no interior do defeito e nos grupos M1, M2 e M3, o calo ósseo formou-se no interior e em grande quantidade na superfície do defeito e no periósteo. Aos 30 dias, o grupo controle exibiu calo ósseo com maturação mais avançada que nos grupos com membranas. Aos 14 e 30 dias, a área de calo ósseo do grupo controle foi significativamente menor em relação aos grupos com membranas (p=0,001 e p=0,003 respectivamente). As lâminas dos grupos com membranas exibiram sinais de remodelação ativa tanto aos 14 como aos 30 dias, denotando o potencial osteoindutor e osteocondutor destes biomateriais. Aos 14 dias a neoformação óssea no grupo M3 (com nano-HA) foi superior ao M2 (com -TCP), o que pode indicar que o potencial osteoindutor e osteocondutor do material M3 foi superior ao M2 nesta fase da reparação. Os resultados permitiram concluir que apesar dos biomateriais testados no experimento estimularem a neoformação óssea, a remodelação foi mais tardia. / Bone gap repairs are a major concern in orthopedics. Autologous cancelous bone graft is considered the golden standard technique, but donation site is limited and its grafting is related to greater morbidity. The use of natural and synthetic materials, as well as growth factors, has been proposed with promising outcomes. The development of membranes and tridimensional matrixes based in reabsorbable and biocompatible materials require more studies targeting their synthesis and evaluation. The aim of the present study was to evaluate the bone repair process using three osteoinductive polymers in circular bone gaps in rabbit\'s tibias. Fourty eight young adult male rabbits were divided into four experimental moments (three, seven, fourteen and thirty days). Each tibia was considered one experimental unit, in which two monocortical bone defects were made in the proximal medial region of the bone. Each experimental time was used in the following four groups: control - without biomaterial; M1 - defects protected with Poli L Lactide co Policaprolactone / Poly Ethylene Glycol; M2 - Poli L Lactide co Policaprolactone / Poly Ethylene Glycol / Tricalcium Phosphate and M3 - Poli L Lactide co Policaprolactone / Poly Ethylene Glycol / Hydroxyapatite. At the end of each period the animals were euthanized and histological sections were stained with HE, TRAP and Masson techniques. Histomorphologic and histomorphometric analysis were made and consisted in the measuring of new bone tissue formation, percentage of trabecular area, number of osteoclast and percentage of trabeculae with osteoclasts. Data were analyzed with Kruskal-Wallis and Mann-Whitney test. Results showed an incomplete absortion and no toxicity of membranes. At 14 and 30 days, control group showed bone callus in the defect, and groups M1, M2 and M3 showed bone callus in the defect and around the surface of the defect. At 30 days, the control group showed bone callus in a more mature phase in comparison to the groups with membranes. At 14 and 30 days, the bone callus area in the control group (p=0.001) was significantly smaller than the membrane groups (p=0.003). The groups with membranes exhibited signs of active remodeling at 14 and 30 days, demonstrating that the biomaterials have greater osteoinduction and osteoconduction potential. At 14 days, we found more bone formation in group M3 (nano-HA) relative to group M2 (-TCP), which may indicate that the osteoinductive / osteoconductive potentials of M3 in this bone repair phase was superior in relation to M2. The biomaterials tested in the study stimulate bone formation, but caused delayed in bone remodeling.
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Caracterização de compostos bioativos de três variedades de Pitanga (Eugenia Uniflora L.) / Characterization of the main bioactive compounds of three pitanga varieties (Eugenia Uniflora L.)Souto, Mariana Magalhães 24 May 2017 (has links)
Os frutos da pitangueira pertencem à família Myrtaceae e podem ser encontrados em três variedades da mesma espécie, reconhecidos de acordo com a cor dos frutos como amarelo, vermelho e roxo. O objetivo deste estudo é caracterizar as três variedades de frutos de pitanga, com relação aos principais carotenoides e compostos fenólicos, e seu comportamento durante o desenvolvimento. Os frutos foram obtidos da região de Campinas (IAC) e fornecidos pela EMBRAPA - (RS). Os extratos metanólico dos frutos foram caracterizados quanto ao conteúdo antocianinas monoméricas, onde somente a variedade roxa, das diferentes plantas e região, apresentou aumento de concentração de antocianinas monoméricas com o desenvolvimento (0,59 a 1,94 mg cy-3-glu eq/g b.s. e 1,43 a 8,47 cy-3-glu eq/g b.s. para o estádio intermediário e maduro, respectivamente. Além disso, a variedade roxa no estádio maduro apresentou maior concentração de fenólicos totais (6,52 a 18,42 mg de AG/g b.s.) quando comparados às outras. O ácido cítrico foi identificado, por CLAE/DAD, como o ácido orgânico majoritário, seguido pelos ácidos succínico e málico, em todas as variedades, com maior concentração no estádio verde. De acordo com a concentração de ácido ascórbico, a pitanga não é uma boa fonte de vitamina C, apresentando valor máximo de 4,0 mg/g b.s no estádio maduro. Os açúcares majoritários encontrados foram a glicose e a frutose. A antocianina majoritária, identificada por LC-ESI-MS/MS, da variedade roxa, no estádio maduro foi a cianidina-3-glicosídeo, com uma variação de 8,05 a 640,53 mg/100g b.s, já o flavonoide majoritário na variedade amarela e vermelha foram miricetina e quercetina em ambas variedades. O carotenoide majoritário identificado por CLAE/DAD, em todas variedades no estádio maduro foi o licopeno, onde a variedade vermelha se destaca pela maior concentração. Dessa forma, o perfil de flavonoides não é alterado com o desenvolvimento, mas é observado uma redução no seu conteúdo nas variedades vermelha e amarela; já a variedade roxa apresenta alteração no perfil de flavonoides, com a expressão de antocianinas no estádio maduro. Por outro lado, o perfil de carotenoides em todas as variedades não sofreu alteração. / The fruits of the pitangueira belong to the family Myrtaceae and can be found in three varieties of the same species, recognized according to the color of the fruits as yellow, red and purple. The aim of this study was characterize the fruits of three pitanga varieties, according to the carotenoids and phenolic compounds composition, and their behavior during ripening. The fruits were obtained from the Campinas region and also provided by EMBRAPA - (RS). Monomeric anthocyaninswere detected only on purple variety, presenting 0.59 to 1.94 mg cy-3-Ο-glu eq/g d.w. and 1.43 to 8.47 cy-3-Ο-glu eq/g d.w.) for the intermediate and mature stages, respectively. In addition, the purple variety at the mature stage had the highest total phenolics concentration (6.52 to 18.42 mg of AG/g d.b.) as compared to other varieties. The citric acid was identified as the major organic acid, followed by succinic and malic acids, in all varieties, with a higher concentration in the green stage. According to the concentration of ascorbic acid, pitanga could not be considered a good source of vitamin C, presenting the highest amount of the 4.0 mg/g d.w. at the mature stage. The major soluble sugars found were glucose and fructose. The major anthocyanin of the purple variety, identified by LC-ESI-MS/MS in the mature stage, was cyanidin-3-Ο-glucoside, ranging from 8.05 to 640.53 mg /100g d.w., whereas the major flavonoids in the yellow and red varieties were myricetin and quercetin. The flavonoid profile was not altered with ripe developing, but a decrease in its content was observed in the red and yellow varieties; on the other hand, the purple variety presented a change in the flavonoid profile, with the expression of anthocyanins in the mature stage. The carotenoids profile in all varieties was the same. The major carotenoid identified by HPLC/DAD, at the mature stage, was lycopene, where the red variety presented the highest concentration.
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Produção e caracterização de amidos e farinhas de Tubérculos Andinos: mashua (Tropaeolum tuberosum) e olluco (Ullucus tuberosus) / Production and characterization of starch and flour from Andean Tubers: mashua (Tropaeolum tuberosum) and olluco (Ullucus tuberosus).Camarena, Denisse Esther Mallaupoma 13 May 2016 (has links)
Este trabalho teve como objetivo a produção e caracterização de farinhas e amidos de mashua (M) e olluco (O) originários da cidade de Tarma (Peru). As farinhas foram produzidas por moagem seca e passagem em peneiras de 45, 120 e 400 mesh Tyler. Os amidos foram isolados a partir dos tubérculos por moagem úmida. As farinhas e os amidos foram caracterizados em função da distribuição do tamanho de partículas (por difração a laser com espalhamento estático de luz), composição centesimal, morfologia (por microscopia eletrônica de varredura - MEV), cristalinidade, propriedades térmicas (por termogravimetria - TG e calorimetria diferencial de varredura - DSC), e espectroscopia de infravermelho por transformada de Fourier (FTIR). As farinhas de mashua e olluco também foram caracterizadas em função da cor, atividade antioxidante, teor de fenólicos totais, antocianinas, betaxantinas, betacianinas e carotenoides totais. As frações de farinhas de mashua e olluco apresentaram tamanhos médios de partícula na faixa de 37,9 a 273,6 ?m, e 31,7 a 274,4 ?m, respectivamente. A fibra e o amido foram os principais componentes das farinhas de mashua e olluco, sendo que a fibra encontra-se em maior concentração na fração mais grossa e o amido, na fração mais fina, independente da espécie de tubérculo. Os amidos dos tubérculos apresentaram padrão de cristalinidade tipo B, avaliados por difração de raios-x (DRX). Na mashua, os formatos dos grânulos foram ovais e esféricos com distribuição polimodal de tamanho de partículas com diâmetros médios das populações entre 1,7 e 31 ?m. Os grânulos de amido de olluco foram maiores (1,9 - 92,3 ?m) com formatos mais assimétricos e irregulares. Com o refino das farinhas, houve um aumento no índice de cristalinidade das frações de farinhas para ambos os tipos de tubérculos sendo quase semelhante aos amidos isolados. O amido de mashua apresentou menor temperatura de pico de gelatinização (60oC) do que o olluco (64,7oC). A cor, atividade antioxidante, teor de compostos fenólicos totais, antocianinas, betaxantinas, betacianinas e carotenoides variaram em função da granulometria das farinhas e/ou do tipo de tubérculo. Conclui-se que o refino das farinhas influenciou no teor de amido, amilose, fibras, cristalinidade, xix estabilidade térmica, cor e teor de compostos antioxidantes. Devido ao seu alto teor de amido e compostos bioativos estas farinhas podem ser usadas como aditivos na indústria de alimentos e farmacêutica, ou para produção de filmes com possíveis propriedades bioativas. / This study aimed to produce and characterize flours and starches from mashua (M) and olluco (O) originating in the city of Tarma (Peru). The flours were produced by dry milling and sieved through 45, 120, and 400 Tyler mesh sieves. Starches were isolated from the tubers by wet grinding. The flours and starches were characterized in terms of particle size distribution (by diffraction laser scattering), chemical composition, morphology (by Scanning Electron Microscopy), crystallinity, thermal properties (by Thermogravimetric Analysis - TG and Differential Scanning Calorimetry - DSC), and Fourier Transform Infrared Spectroscopy (FTIR). Mashua and olluco flours were also studied for their color, antioxidant activity, and total phenolics, anthocyanin, betaxanthin, betacyanin, and carotenoid contents. The particle sizes ranged from 37,9 to 273,6 ?m and from 31,7 to 274,4 ?m for the mashua and olluco flour fractions, respectively. Total fibers and starch were the main components of the tuber flours. Fibers and starch were the major components in the thicker and thinner fractions, respectively, regardless of the tuber crop. Mashua starch granules exhibited oval and spherical shape, and particle sizes with polymodal distribution and average diameter between 1,7 to 31 ?m. Olluco starch granules were larger (1,9-92,3 ?m) and more asymmetric and irregular than mashua starch granules. Tuber starches showed crystallinity type B, evaluated by X-ray diffraction. Considering the same tuber species, the flour fraction containing thinner particles and the isolated starch presented similar crystallinity index. Mashua starch had lower gelatinization peak temperature (60 oC) than olluco starch (64.7 oC). Color, antioxidant activity, and total phenolics, anthocyanin, betaxanthin, betacyanin, and carotenoid contents varied according to the flour particle sizes and/or the tuber species. Therefore, refining tuber flours influenced starch, amylose, and fiber contents, crystallinity, thermal stability, color, and antioxidant activity of the resulting flours. Because of their high contents of starch and bioactive compounds, these flours can be used as additives in the food industry and pharmacy, and they can also be employed in the production of bioactive films.
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Estudo dos parâmetros fermentativos, características físico-químicas e sensoriais de hidromel / Study of the fermentative parameters, physicochemical and sensory characteristics of meadFlavio de Oliveira Ferraz 28 November 2014 (has links)
Na primeira etapa deste trabalho avaliou-se o desempenho fermentativo de 6 cepas de leveduras comerciais utilizadas na produção de vinhos e cerveja, em mosto de mel 30°Brix suplementado com 0,5 g/L de peptona e 1 g/L de extrato de levedura. Como resposta determinou-se o crescimento das leveduras em número de células e as concentrações de glicose, frutose e etanol por HPLC, que permitiram determinar os parâmetros rendimento, eficiência de fermentação e produtifidade em etanol, bem como a produção de sulfeto de hidrogênio. Assim, selecionou-se a cepa Saccharomyces bayanus - Pasteur Champagne - Red Star, que teve seu comportamento avaliado em mosto de mel suplementado com diferentes nutrientes. Os resultados demonstraram que a suplementação do mosto de mel com sais ou com suplemento comercial Enovit contribuiu para o bom desempenho da referida cepa. Na etapa seguinte, estudou-se a produção de hidromel em escala piloto a 18°C em reatores de polipropileno contendo 130 L de mosto sem suplementação (controle), suplementado com Enovit e suplementado com pedaços de maçãs (10% m/v). Terminada a fermentação, após 60 dias, o hidromel foi devidamente caracterizado físico-quimicamente quanto aos padrões de qualidade e identidade para hidromel estabelecidos pela Legislação Brasileira. Os resultados demonstraram que, com exceção da acidez total, todos os parâmetros avaliados se encontravam em consonância com os referidos padrões. Assim, as formulações estudadas foram adequadas para a obtenção de hidromel. Terminada a fermentação o hidromel foi submetido ao processo de envelhecimento a 20°C, por 216 dias, em tonel de carvalho (50L); galão de plástico (20 L); e frasco de vidro tipo bolha (20L), sendo neste período, caracterizado físico-químicamente, bem como quanto aos teores de compostos fenólicos totais, capacidade antioxidante, presença de aminas bioativas e compostos aromáticos derivados do tonel de carvalho. O hidromel envelhecido em galão de plástico apresentou teores de extrato seco reduzido abaixo do mínimo estabelecido nos padrões da legislação. A utilização de maçãs como suplemento do mosto de mel resultou em hidromel com maior teor de compostos fenólicos e maior capacidade antioxidante. As concentrações de aminas bioativas encontradas não comprometem a qualidade do hidromel, nem oferecem risco à saúde do consumidor. A análise de compostos fenólicos dos hidroméis envelhecidos em tonel de carvalho revelou que o processo de envelhecimento promoveu a extração de furfural, vanilina e ácido gálico, compostos que contribuem para o perfil sensorial da bebida, ficaram abaixo do limiar de percepção sensorial, fato que pode ser alterado pelo aumento do tempo de envelhecimento. Quanto a intenção de compra, os hidroméis avaliados apresentaram mais de 50% de notas variando entre 3 (tenho dúvidas se compraria) e 5 (certamente compraria), sendo os de melhor aceitação envelhecidos em recipientes de plástico e vidro. A análise sensorial revelou pouca influência do recipiente de envelhecimento sobre os atributos avaliados e a intensão de compra mostrou que os provadores preferiram os hidroméis envelhecidos em recipientes inertes (vidro e plástico). Diante do exposto, conclui-se que a produção de hidromel e seu posterior envelhecimento, por 216 dias, em recipientes inertes ou em tonéis de carvalho recondicionados, resultam em bebidas que apresentam boa aceitação, sendo uma alternativa viável para apicultores diversificarem a sua produção. / In the first stage of this work it was evaluated the fermentation performance of six commercial strains of yeast used in the of wine and beer production in honey wort 30 °Brix supplemented with 0.5 g / L peptone and 1 g / L yeast extract. In response, it was determined the yeast growth by number of cells and concentrations of glucose, fructose and ethanol by HPLC, as well as fermentation parameters as yield, efficiency and productivity in ethanol, and the production of hydrogen sulfide. Saccharomyces bayanus -Pasteur Champagne - Red Star showed better fermentation performance and it was evaluated in honey wort supplemented with different nutrients. The results showed that must supplementation with salts or commercial supplement Enovit contributes to the yeast performance. In the next step, it was studied the production of mead on a pilot scale at 18 ° C in polypropylene reactors containing 130 L of wort without supplementation (control), supplemented with Enovit and supplemented with apple pieces (10% m/v). By the end of fermentation, after 60 days, mead was properly characterized physico-chemically regarding the standards of quality and identity for mead, established by Brazilian legislation. The results showed that, with the exception of total acidity, all parameters were in accordance with the standards. After the fermentation, mead was subjected to aging process at 20 ° C by 216 days in oak barrel (50L) plastic gallon (20 L) and glass bottle (20L), and was characterized physico-chemically, as well as regarding the content of total phenolics, antioxidant capacity, presence of bioactive amines and aromatic compounds derived from the oak barrel. The results showed that the mead aged in plastic gallon presented content of \"reduced dried extract\" below the minimum patterns stated. It was also observed that the use of apples as the must supplement resulted in honey mead with a higher content of phenolic compounds and antioxidant capacity. The concentrations of bioactive amines found do not compromise the quality of mead, neither consumer health. The analysis of phenolic compounds in meads aged in oak barrel revealed that the aging process promoted the extraction of furfural, vanillin, gallic acid, compounds which contribute to the sensory profile of the beverage. Concentrations of these compounds were below the threshold of sensory perception, which can be changed by increasing aging time. Regarding purchase intent, all meads evaluated obtained more than 50% of positive scores, ranging between 3 (I doubt if buy) and 5 (definitely would buy), and meads aged in plastic and glass containers showed better acceptance. Sensory analysis showed little influence of the aging container on the attributes evaluated and the tasters preferred the meads aged in inert containers. So,it is concluded that the production of mead and its subsequent aging in inert containers or reconditioned oak casks, resulted in beverages that have good acceptance and are a viable alternative for beekeepers to diversify their products.
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