Thesis (Masters)--California Institute of Technology, 1989. / Title from home page. Viewed 02/09/10. Includes bibliographical references.

Thesis--Wisconsin. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1976. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Bibliographical references.

Orientador: Salvador M. Roig / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-20T23:21:40Z (GMT). No. of bitstreams: 1 Costa_RicardoCalvo_M.pdf: 2710464 bytes, checksum: 2f1749d07b2a3e39917bedff151f819f (MD5) Previous issue date: 1995 / Resumo: Neste trabalho foi estudada a extração de lactose a partir de permeado de leite e de permeado de soro de queijo, obtidos por ultrafiltração de leite e soro de queijo. A antecipação da etapa de descoloração foi estudada com o objetivo de eliminar a etapa de refino no processo tradicional e obter uma lactose de alto teor de pureza. A pasta descorante composta de 750/0 de carvão ativo e negro de ossos e 25% de ácido clorídrico concentrado foi adicionada aos permeados de leite e de soro de queijo, e somente resultou em descoloração quando foram utilizados teores de pasta superiores a 8% da massa de lactose presente no permeado. Os melhores resultados foram obtidos a partir de permeado de leite, obtido através de ultrafiltração de leite em um sistema de ultrafiltração dotado de membranas minerais, sem descoloracão do permeado. Os compostos coloridos foram retidos durante o processo de ultrafiltração resultando em um permeado límpido. O melhor processo obtido para extração de lactose a partir de permeado foi ultrafiltração do leite em membrana mineral, seguido de concentração à vácuo do permeado, cristalização, separação, lavagem dos cristais com água a 5°e e secagem. A partir de permeado de leite com 0,027% de nitrogênio total 0,49% de cinzas e 4,71 % de lactose foi obtida lactose com 99,3% de pureza 0,66% de cinzas e 0,07% de nitrogênio total / Abstract: The lactose extraction by ultrafiltration from milk and whey permeates was studied. The aim of this work was to eliminate the refining step of the traditional process and produce a high purity level lactose yield before the discolouring step. The discolouring paste which is made of 75% of a mixture of active carbon and black bone and 25% of concentrated hydrogen chloride was added to milk and whey permeates resulting in discolouring only when the paste concentration was higher than 8% in relation to the lactose mass in the permeate. The best results carne from milk permeate processed in a mineral membranes milk ultrafiltration system without the discolouring step. The colouring compounds were retained in the ultrafiltration process resulting in a cleaned permeate. The best process to lactose extraction from permeate was milk ultrafiltration in a mineral membrane system followed by permeate vacuum concentration, crystallization, separation and crystal washing with 't\1Iter at 5°e and drying. From mill permeate with 0,027% total nitrogen, 0,49% ash and 4,71% of lactose it was possible to obtain lactose with a purity of 99,3%, 0.660% ash and 0,07% total nitrogen contents / Mestrado / Mestre em Tecnologia de Alimentos

Lactose is a widely used excipient in capsules and tablets. It has two anomeric forms, ⍺ (usually a monohydrate) and β (anhydrous). Lactose NF XVI is usually ⍺-lactose monohydrate. Physical properties, such as thermal behavior, x-ray diffraction characteristics, and true density of the anomers are different and not clearly understood. Pure samples of each anomer are difficult to prepare and all commercial lactose samples, especially the directly compressible grades, contain a certain amount of each anomer. It is not clearly established in what physical form the two anomers are present in a commercial sample. The physical form, and also certain differences in the physical properties, may depend upon the anomeric composition. An accurate and rapid gas chromatographic (GC) method for the determination of anomeric composition was developed. It involved derivatization of the lactose samples using trimethylsilylimidazole (TSIM). A mixture of TSIM in dimethylsulfoxide (DMSO) and pyridine (PYR) was used. DMSO dissolved the samples and PYR stabilized the solutions by preventing a phase separation which occurred if only TSIM and DMSO were used. Alpha-rich samples were dissolved directly into the mixture. Beta-rich samples were first dissolved in DMSO and then derivatized using a mixture of TSIM and PYR. An OV-225 column with helium as carrier gas was used for separating the anomers. The relative response of the anomers at a flame ionization detector was equal. Thus, the relative anomeric peak areas could be used as relative anomeric amounts. This avoided the use of an internal standard. The anomeric composition of a number of lactose samples was determined and was found to vary from 1.9 to 98.4% ⍺. A study of the thermal behavior of commercial lactose samples using differential scanning calorimetry and thermal microscopy showed that all ⍺-lactose monohydrate rich samples exhibited a dehydration peak followed by a melting peak when heated in an open pan. In sealed pans, the dehydration peak split into two components because of an overlap of an exotherm (due to dissolution of anhydrous lactose in the liquid water formed in the sealed pan, and recrystallization of β-lactose from the solution) with the endothermic dehydration peak. The extent of the split varied with the heating rate (which controls the extent of dissolution). Two new peaks, an endotherm and an exotherm, also appeared after the dehydration peak. The endotherm is due to anomeric conversion (determined using the GC method) rather than melting, and the exotherm is due to recrystallization into a new crystal lattice as the sample became β-rich. Since β-rich samples normally have a higher melting point than ⍺-rich samples, the melting peak shifted to a higher temperature when sealed pans were used. An unstable anhydrous a-lactose sample also showed the endotherm (anomeric conversion) and the exotherm (recrystallization of the β-rich form). On the basis of their powder x-ray diffraction patterns, the lactose samples can be classified into three types: 1. ⍺-lactose monohydrate rich, 2. β-rich, and, 3. samples showing peaks of both ⍺-lactose monohydrate and β-lactose. It was shown using quantitative x-ray diffraction that samples did not contain their anomeric impurity as a simple physical mixture. The true density of the lactose samples also varied with their anomeric composition. Beta-rich samples had greater true density than a-rich samples. This can be attributed to: 1. a simple physical mixture of ⍺-lactose monohydrate and β-lactose crystals, 2. a continuous substitutional solid solution, 3. an interstitial solid solution, or, 4. a mixture of two solid solutions. The first possibility was ruled out using quantitative x-ray diffraction because the relative anomeric x-ray peak intensities did not match the anomeric composition determined by GC. The second possibility was ruled out because there was no gradual shift of peaks in the x-ray diffraction patterns with the anomeric composition. The formation of an interstitial solid solution was not possible because this occurs only if the solute and solvent have very different molecular sizes. The quantitative x-ray diffraction experiments suggest that most samples contain a mixture of two solid solutions. Sorbed-moisture and surface area are important factors in tabletting. Various commercial lactose samples had specific surface areas ranging from 0.108 to 0.574 m²/g- Moisture-desorption and sorption were found to depend more on the relative crystallinities of the samples than on their surface areas. / Pharmaceutical Sciences, Faculty of / Graduate

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains ix, 50 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 40-44).

Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains x, 74 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 55-60).

Objetivo: Verificar a relação entre a presença das mutações C/T-13910 e G/A-22018 no gene da lactase-florizina hidrolase e a absorção de lactose em indivíduos residentes no município de Porto Alegre. Casuística e Métodos: Foi realizado um estudo transversal que incluiu 20 indivíduos adultos, sadios, com idade superior a 18 anos, procedentes do município de Porto Alegre. Os participantes foram classificados segundo o relato da quantidade de leite consumida, habitualmente, por dia e quanto à presença ou ausência de sintomas relacionados à ingestão de leite. A má absorção de lactose foi diagnosticada através do teste de hidrogênio expirado após a ingestão de 50 g de lactose diluída em solução aquosa a 20%. O teste teve duração de 3 horas e foi considerado positivo quando o aumento foi superior a 20 partes por milhão na concentração de H2 em relação ao nível basal. Os voluntários também foram classificados como indivíduos com lactase persistente e lactase não persistente através da análise molecular dos dois polimorfismos (C/T-13910 e G/A-22018) responsáveis pela persistência ou não da Lactase Florizina Hidrolase no adulto pelo método da Reação em Cadeia da Polimerase (PCR). Resultados: Foram estudados 20 indivíduos com média de idade de 32,7 ± 7,3 anos. 9/20 sujeitos apresentaram o genótipo CCGG – não persistência de lactase em concordância com o teste do hidrogênio expirado positivo. 11/20 indivíduos apresentaram o teste H2 expirado negativo, sendo que 10/20 apresentaram genótipos de persistência de lactase (1/20 CTAA, 3/20 TTAA e 6/20 CTGA) e 1 sujeito com o genótipo de não persistência de lactase (CCGG). Obteve-se um coeficiente de concordância kappa = - 0,9 entre os testes, molecular e de H2 expirado com p < 0,001. Conclusões: Os resultados do trabalho permitem concluir que a análise dos polimorfismos C/T-13910 e G/A-22018 no gene da Lactase Florizina Hidrolase podem ser considerados um bom indicador para o diagnóstico de má absorção de lactose, visto que é um método bastante sensível e específico com ótima concordância com o teste de hidrogênio expirado. / Objective: to verify the relation between the presence of mutations C/T–13910 and G/A–22018 in the gene of lactase-phlorizin hydrolase and the absorption of lactose in individuals who live in the city of Porto Alegre. Methods: It consists of a transversal study which included 20 healthy adult individuals over eighteen years old, from the city of Porto Alegre. The participants were classified according to reports on the quantity of milk they habitually consumed per day and in regard to the presence or absence of symptoms related to lactose intolerance. Lactose malabsorption was diagnosed through the hydrogen breath test after the ingestion of 50g of lactose diluted in watery solution. The test lasted 3 hours and it was considered positive when the increase was higher than 20 parts per million on concentration of H2 in relation to the basal level. The volunteers were also classified as individuals with persistent and nonpersistent lactase through the analysis of the presence of both polyformisms (C/T–13910 and G/A–22018), which are responsible for the persistence or not of Lactase Phlorizin Hydrolase in adults. The analysis was made through the Polymerase Chain Reaction method (PCR). Results: Twenty individuals were studied with mean age of 32.7 ± 7.3 years. 9/20 subjects presented with the CCGG genotype – non-persistence of lactase accordingly to the positive hydrogen breath test (HBT). 11/20 individuals presented with negative HBT, whereas 10/20 presented with genotypes of lactase persistence (1/20 CTAA, 3/20 TTAA e 6/20 CTGA) and one subject with genotype of non-persistence of lactase (CCGG). An agreement coefficient kappa = - 0.9 was obtained between the molecular and the hydrogen breath test with p < 0,001. Conclusions: This project results make it possible to conclude that the analysis of the polyformisms C/T–13910 and G/A–22018 in the gene of Lactase Phlorizin Hydrolase can be considered a good indicator for the diagnosis for lactose malabsorption, since it is a very sensible and specific method, as it was demonstrated in recent studies. It also has an excellent agreement with the expired hydrogen.

Objetivo: Verificar a relação entre a presença das mutações C/T-13910 e G/A-22018 no gene da lactase-florizina hidrolase e a absorção de lactose em indivíduos residentes no município de Porto Alegre. Casuística e Métodos: Foi realizado um estudo transversal que incluiu 20 indivíduos adultos, sadios, com idade superior a 18 anos, procedentes do município de Porto Alegre. Os participantes foram classificados segundo o relato da quantidade de leite consumida, habitualmente, por dia e quanto à presença ou ausência de sintomas relacionados à ingestão de leite. A má absorção de lactose foi diagnosticada através do teste de hidrogênio expirado após a ingestão de 50 g de lactose diluída em solução aquosa a 20%. O teste teve duração de 3 horas e foi considerado positivo quando o aumento foi superior a 20 partes por milhão na concentração de H2 em relação ao nível basal. Os voluntários também foram classificados como indivíduos com lactase persistente e lactase não persistente através da análise molecular dos dois polimorfismos (C/T-13910 e G/A-22018) responsáveis pela persistência ou não da Lactase Florizina Hidrolase no adulto pelo método da Reação em Cadeia da Polimerase (PCR). Resultados: Foram estudados 20 indivíduos com média de idade de 32,7 ± 7,3 anos. 9/20 sujeitos apresentaram o genótipo CCGG – não persistência de lactase em concordância com o teste do hidrogênio expirado positivo. 11/20 indivíduos apresentaram o teste H2 expirado negativo, sendo que 10/20 apresentaram genótipos de persistência de lactase (1/20 CTAA, 3/20 TTAA e 6/20 CTGA) e 1 sujeito com o genótipo de não persistência de lactase (CCGG). Obteve-se um coeficiente de concordância kappa = - 0,9 entre os testes, molecular e de H2 expirado com p < 0,001. Conclusões: Os resultados do trabalho permitem concluir que a análise dos polimorfismos C/T-13910 e G/A-22018 no gene da Lactase Florizina Hidrolase podem ser considerados um bom indicador para o diagnóstico de má absorção de lactose, visto que é um método bastante sensível e específico com ótima concordância com o teste de hidrogênio expirado. / Objective: to verify the relation between the presence of mutations C/T–13910 and G/A–22018 in the gene of lactase-phlorizin hydrolase and the absorption of lactose in individuals who live in the city of Porto Alegre. Methods: It consists of a transversal study which included 20 healthy adult individuals over eighteen years old, from the city of Porto Alegre. The participants were classified according to reports on the quantity of milk they habitually consumed per day and in regard to the presence or absence of symptoms related to lactose intolerance. Lactose malabsorption was diagnosed through the hydrogen breath test after the ingestion of 50g of lactose diluted in watery solution. The test lasted 3 hours and it was considered positive when the increase was higher than 20 parts per million on concentration of H2 in relation to the basal level. The volunteers were also classified as individuals with persistent and nonpersistent lactase through the analysis of the presence of both polyformisms (C/T–13910 and G/A–22018), which are responsible for the persistence or not of Lactase Phlorizin Hydrolase in adults. The analysis was made through the Polymerase Chain Reaction method (PCR). Results: Twenty individuals were studied with mean age of 32.7 ± 7.3 years. 9/20 subjects presented with the CCGG genotype – non-persistence of lactase accordingly to the positive hydrogen breath test (HBT). 11/20 individuals presented with negative HBT, whereas 10/20 presented with genotypes of lactase persistence (1/20 CTAA, 3/20 TTAA e 6/20 CTGA) and one subject with genotype of non-persistence of lactase (CCGG). An agreement coefficient kappa = - 0.9 was obtained between the molecular and the hydrogen breath test with p < 0,001. Conclusions: This project results make it possible to conclude that the analysis of the polyformisms C/T–13910 and G/A–22018 in the gene of Lactase Phlorizin Hydrolase can be considered a good indicator for the diagnosis for lactose malabsorption, since it is a very sensible and specific method, as it was demonstrated in recent studies. It also has an excellent agreement with the expired hydrogen.

Objetivo: Verificar a relação entre a presença das mutações C/T-13910 e G/A-22018 no gene da lactase-florizina hidrolase e a absorção de lactose em indivíduos residentes no município de Porto Alegre. Casuística e Métodos: Foi realizado um estudo transversal que incluiu 20 indivíduos adultos, sadios, com idade superior a 18 anos, procedentes do município de Porto Alegre. Os participantes foram classificados segundo o relato da quantidade de leite consumida, habitualmente, por dia e quanto à presença ou ausência de sintomas relacionados à ingestão de leite. A má absorção de lactose foi diagnosticada através do teste de hidrogênio expirado após a ingestão de 50 g de lactose diluída em solução aquosa a 20%. O teste teve duração de 3 horas e foi considerado positivo quando o aumento foi superior a 20 partes por milhão na concentração de H2 em relação ao nível basal. Os voluntários também foram classificados como indivíduos com lactase persistente e lactase não persistente através da análise molecular dos dois polimorfismos (C/T-13910 e G/A-22018) responsáveis pela persistência ou não da Lactase Florizina Hidrolase no adulto pelo método da Reação em Cadeia da Polimerase (PCR). Resultados: Foram estudados 20 indivíduos com média de idade de 32,7 ± 7,3 anos. 9/20 sujeitos apresentaram o genótipo CCGG – não persistência de lactase em concordância com o teste do hidrogênio expirado positivo. 11/20 indivíduos apresentaram o teste H2 expirado negativo, sendo que 10/20 apresentaram genótipos de persistência de lactase (1/20 CTAA, 3/20 TTAA e 6/20 CTGA) e 1 sujeito com o genótipo de não persistência de lactase (CCGG). Obteve-se um coeficiente de concordância kappa = - 0,9 entre os testes, molecular e de H2 expirado com p < 0,001. Conclusões: Os resultados do trabalho permitem concluir que a análise dos polimorfismos C/T-13910 e G/A-22018 no gene da Lactase Florizina Hidrolase podem ser considerados um bom indicador para o diagnóstico de má absorção de lactose, visto que é um método bastante sensível e específico com ótima concordância com o teste de hidrogênio expirado. / Objective: to verify the relation between the presence of mutations C/T–13910 and G/A–22018 in the gene of lactase-phlorizin hydrolase and the absorption of lactose in individuals who live in the city of Porto Alegre. Methods: It consists of a transversal study which included 20 healthy adult individuals over eighteen years old, from the city of Porto Alegre. The participants were classified according to reports on the quantity of milk they habitually consumed per day and in regard to the presence or absence of symptoms related to lactose intolerance. Lactose malabsorption was diagnosed through the hydrogen breath test after the ingestion of 50g of lactose diluted in watery solution. The test lasted 3 hours and it was considered positive when the increase was higher than 20 parts per million on concentration of H2 in relation to the basal level. The volunteers were also classified as individuals with persistent and nonpersistent lactase through the analysis of the presence of both polyformisms (C/T–13910 and G/A–22018), which are responsible for the persistence or not of Lactase Phlorizin Hydrolase in adults. The analysis was made through the Polymerase Chain Reaction method (PCR). Results: Twenty individuals were studied with mean age of 32.7 ± 7.3 years. 9/20 subjects presented with the CCGG genotype – non-persistence of lactase accordingly to the positive hydrogen breath test (HBT). 11/20 individuals presented with negative HBT, whereas 10/20 presented with genotypes of lactase persistence (1/20 CTAA, 3/20 TTAA e 6/20 CTGA) and one subject with genotype of non-persistence of lactase (CCGG). An agreement coefficient kappa = - 0.9 was obtained between the molecular and the hydrogen breath test with p < 0,001. Conclusions: This project results make it possible to conclude that the analysis of the polyformisms C/T–13910 and G/A–22018 in the gene of Lactase Phlorizin Hydrolase can be considered a good indicator for the diagnosis for lactose malabsorption, since it is a very sensible and specific method, as it was demonstrated in recent studies. It also has an excellent agreement with the expired hydrogen.