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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

Potential sources of chryseobacterium contamination during poultry processing : a pilot study

De Beer, H., Hugo, C.J. January 2010 (has links)
Published Article / The genus Chryseobacterium is often found in food and is regarded as a food spoilage organism. In this study, the source of the chryseobacteria was uncertain. As an exploratory investigation, the potential source of chryseobacterial contamination was determined. Total bacteria counts and yellow-pigmented colony counts were performed. Chryseobacterium species were present on poultry carcasses at all stages of processing. Total Chryseobacterium counts increased from 5.6 to 11.8 % after the brine injection stage. A significant increase in total Chryseobacterium counts (20.0 and 25.2 %) in the processing waters occurred where cutting up of the carcasses was involved. It is speculated that live chickens are the source of contamination.
2

The potential of Chryseobacterium species to produce biogenic amines

Mielmann, A, Hugo, C, Jooste, PJ January 2010 (has links)
Abstract The food spoilage potential of the genus Chryseobacterium has not been studied in equal detail than the taxonomy of this genus. The ability of seven Chryseobacterium species to produce biogenic amines (BAs) at different temperatures and sodium chloride concentrations, was investigated by using amodified Niven medium. Temperatures at and below 15C and 25C seemed to have a definite inhibitory effect on the production of BAs in some Chryseobacterium species. Salt concentrations in excess of 4% would be needed to prevent amine production of Chryseobacterium species in food products. Chryseobacterium species have therefore the ability to decarboxylate some precursors of BAs, making them important spoilage bacteria in dairy food products.
3

Chryseobacterium vrystaatense sp. nov., isolated from raw chicken in a chicken-processing plant

de Beer, H, Hugo, CJ, Jooste, PJJ, Willems, A, Vancanneyt, M, Coenye, T, Ranst, E, Verplancke, H, Vandamme, AR 03 June 2005 (has links)
Flavobacteria and pseudomonads are traditionally known to cause spoilage in food and food products (Forsythe, 2000, pp. 96–98 and 101–103). In the literature on meat spoilage, ‘flavobacteria’ is used as a generic name for yellowpigmented rods (Hendrie et al., 1969). Usually, pathogens such as Salmonella and Campylobacter are associated with poultry, but large numbers of other bacteria often associated with spoilage are found on poultry carcasses. These include many so-called flavobacteria that may originate from the poultry itself or from the abattoir environment and which are responsible for spoilage (Hang’ombe et al., 1999). Mai & Conner (2001) found that the incidence of members of the genus Pseudomonas and flavobacteria on chicken carcasses was 17 and 16 %, respectively. The incidence of flavobacteria on poultry is much higher than on other fresh meat (Nychas & Drosinos, 1999). Over the past decade, many changes have taken place in the taxonomy of the family Flavobacteriaceae, and the revised genus Flavobacterium comprises mainly aquatic bacteria that are not known in food microbiology (Bernardet et al., 1996). Several former Flavobacterium species were transferred to the novel genus Chryseobacterium (Vandamme et al., 1994) and novel species have been described, including Chryseobacterium joostei (Hugo et al., 2003), Chryseobacterium defluvii (Ka¨mpfer et al., 2003), Chryseobacterium miricola (Li et al., 2003) and, most recently, Chryseobacterium formosense (Young et al., 2005), Chryseobacterium daecheongense (Kim et al., 2005a) and Chryseobacterium taichungense (Shen et al., 2005). ‘Chryseobacterium proteolyticum’ was described by Yamaguchi & Yokoe (2000), but its name has not been validly published. In addition, two Chryseobacterium species, Chryseobacterium meningosepticum and Chryseobacterium miricola, have been reclassified into the novel genus Elizabethkingia (Kim et al., 2005b). In general, these Chryseobacterium species are widely distributed in water, soil and the clinical environment, but they are also found in food specimens, such as milk, meat, poultry and fish (Jooste & Hugo, 1999).
4

Purificação e imobilização de uma protease queratinolítica produzida por Chryseobacterium sp. linhagem Kr6 / Purification and immobilization of a protease keratinolytic from Chryseobacterium sp. strain kr6

Silveira, Silvana Terra January 2009 (has links)
Queratinases (E.C. 3.4.21/24/99.11) são um grupo de enzimas proteolíticas que catalisam a hidrólise da queratina. A linhagem queratinolítica Chryseobacterium sp. kr6 apresenta elevada produção de queratinases extracelulares, demonstrando potencial para bioconversão de substratos constituídos por queratina. O presente trabalho teve como principal objetivo purificar e imobilizar uma queratinase produzida pelo Chryseobacterium sp. kr6. As condições ótimas para a atividade proteolítica da queratinase foram estabelecidas com o auxílo das ferramentas estatísticas de planejamento experimental e superfície de resposta. Os resultados demonstraram que tais condições foram atingidas ao utilizar pH na faixa de 7,4 a 9,2, 35°C a 50°C e concentração de NaCl de 50 a 340 mmol L-1. A especificidade da queratinase frente a diferentes substratos também foi investigada, indicando a preferência da enzima por resíduos hidrofóbicos ou positivamente carregados. A completa purificação da queratinase envolveu a precipitação com sulfato de amônio, cromatografias de permeação em gel e troca aniônica. A amostra obtida após as referidas etapas apresentou um fator de purificação de 40,2 vezes e atividade específica de 21.466 U mg-1 de proteína. A massa molecular da enzima, determinada por SDS-PAGE, foi, de aproximadamente, 20 kDa. Os parâmetros cinéticos e termodinâmicos para a inativação térmica da queratinase, sob diferentes condições, foram estimados. A partir dos resultados obtidos, observou-se que a presença de cálcio aumenta significativamente a estabilidade térmica da enzima. Comparando com as amostras controles, o tempo de meia vida da enzima purificada na presença de Ca2+ aumentou 7,3, 20,2 e 9,8 vezes, a 50°C, 55°C e 60ºC, respectivamente. A atividade enzimática foi significativamente inibida na presença de EDTA e 1,10-fenantrolina, sugerindo se tratar de uma metaloprotease. O desenvolvimento de um suporte a base de quitosana para a imobilização covalente da queratinase purificada foi investigado. Para isso, foram avaliados os efeitos de diferentes concentrações de glutaraldeído e tempo de contato deste com as esferas de quitosana, sobre o percentual de imobilização da enzima. Os melhores resultados obtidos para a imobilização da queratinase ao suporte foram ao utilizar concentração de glutaraldeído na faixa de 34 a 56 g L-1 e um período de ativação das esferas na faixa de 6 a 10 h. Sob tais condições, obteve-se 80% de imobilização da enzima. A partir das condições ótimas para a imobilização da enzima ao suporte, apontadas pela metodologia de superfície de resposta, estimou-se a capacidade de carga máxima do suporte, sendo esta de 58,8 U g-1. A enzima imobilizada apresentou maior estabilidade térmica quando comparada com a forma livre, além de reter 63,4% da atividade enzimática inicial após cinco reutilizações. / Keratinases (E.C. 3.4.21/24/99.11) are a group of proteolytic enzymes that are able to catalize the keratin hydrolysis. The keratinolytic Chryseobacterium sp. kr6 strain shows high extracellular keratinases production, suggesting potential for bioconversion of keratinous substrates. The present work had as main objective to purify and immobilize a keratinase from Chryseobacterium sp. kr6. The optimal conditions for proteolytic activity were established with aid of experimental design and response surface methodology. The results demonstrated that the best conditions were at pH range of 7.4 to 9.2, 35°C to 50°C and NaCl concentration from 50 to 340 mmol L-1. Keratinase specificity for various substrates also was investigated, suggesting that the enzyme had preference for hydrophobic and positively charged residues. The keratinase purification involved precipitation with ammonium sulphate and chromatographic techniques of gel permeation and anionic exchange. The final sample obtained after the purification steps presents a purification factor of 40.2-fold and specific activity of 21,466 U mg-1 of protein. The molecular weight of the enzyme, determined by SDS-PAGE, was around 20 kDa. The kinetics and thermodynamics parameters for thermal keratinase inactivation, under different conditions, were estimated. From results, it was possible to observe that the calcium affect significantly the thermal stability of the enzyme. Comparing with the control samples, the half-life time of the purified enzyme with calcium increased about 7.3, 20.2 and 9.8-fold, at 50°C, 55°C and 60°C, respectively. The enzyme activity was significantly inhibited in the presence of EDTA and 1,10- phenanthroline, suggesting that the enzyme belongs to metalloprotease group. The developing of a chitosan support for covalent immobilization of the purified keratinase was investigated. The effects of different glutaraldehyde concentrations, as well as, the activation time required for the chitosan beads on the enzyme immobilization were investigated. The optimal conditions for enzyme immobilization were at glutaraldehyde concentration ranging from 34 to 56 g L-1 and activation time of 6 to 10 h. Under these conditions, above 80% of added enzyme was covalently immobilized on the support. From the best conditions, indicated by response surface methodology, the load capacity of the macrospheres was estimated, being of 58.8 U g-1. The immobilized enzyme presented higher thermal stability when compared with free one, besides it retained 63,4% of the initial enzyme activity after five cicles of reuse.
5

Purificação e imobilização de uma protease queratinolítica produzida por Chryseobacterium sp. linhagem Kr6 / Purification and immobilization of a protease keratinolytic from Chryseobacterium sp. strain kr6

Silveira, Silvana Terra January 2009 (has links)
Queratinases (E.C. 3.4.21/24/99.11) são um grupo de enzimas proteolíticas que catalisam a hidrólise da queratina. A linhagem queratinolítica Chryseobacterium sp. kr6 apresenta elevada produção de queratinases extracelulares, demonstrando potencial para bioconversão de substratos constituídos por queratina. O presente trabalho teve como principal objetivo purificar e imobilizar uma queratinase produzida pelo Chryseobacterium sp. kr6. As condições ótimas para a atividade proteolítica da queratinase foram estabelecidas com o auxílo das ferramentas estatísticas de planejamento experimental e superfície de resposta. Os resultados demonstraram que tais condições foram atingidas ao utilizar pH na faixa de 7,4 a 9,2, 35°C a 50°C e concentração de NaCl de 50 a 340 mmol L-1. A especificidade da queratinase frente a diferentes substratos também foi investigada, indicando a preferência da enzima por resíduos hidrofóbicos ou positivamente carregados. A completa purificação da queratinase envolveu a precipitação com sulfato de amônio, cromatografias de permeação em gel e troca aniônica. A amostra obtida após as referidas etapas apresentou um fator de purificação de 40,2 vezes e atividade específica de 21.466 U mg-1 de proteína. A massa molecular da enzima, determinada por SDS-PAGE, foi, de aproximadamente, 20 kDa. Os parâmetros cinéticos e termodinâmicos para a inativação térmica da queratinase, sob diferentes condições, foram estimados. A partir dos resultados obtidos, observou-se que a presença de cálcio aumenta significativamente a estabilidade térmica da enzima. Comparando com as amostras controles, o tempo de meia vida da enzima purificada na presença de Ca2+ aumentou 7,3, 20,2 e 9,8 vezes, a 50°C, 55°C e 60ºC, respectivamente. A atividade enzimática foi significativamente inibida na presença de EDTA e 1,10-fenantrolina, sugerindo se tratar de uma metaloprotease. O desenvolvimento de um suporte a base de quitosana para a imobilização covalente da queratinase purificada foi investigado. Para isso, foram avaliados os efeitos de diferentes concentrações de glutaraldeído e tempo de contato deste com as esferas de quitosana, sobre o percentual de imobilização da enzima. Os melhores resultados obtidos para a imobilização da queratinase ao suporte foram ao utilizar concentração de glutaraldeído na faixa de 34 a 56 g L-1 e um período de ativação das esferas na faixa de 6 a 10 h. Sob tais condições, obteve-se 80% de imobilização da enzima. A partir das condições ótimas para a imobilização da enzima ao suporte, apontadas pela metodologia de superfície de resposta, estimou-se a capacidade de carga máxima do suporte, sendo esta de 58,8 U g-1. A enzima imobilizada apresentou maior estabilidade térmica quando comparada com a forma livre, além de reter 63,4% da atividade enzimática inicial após cinco reutilizações. / Keratinases (E.C. 3.4.21/24/99.11) are a group of proteolytic enzymes that are able to catalize the keratin hydrolysis. The keratinolytic Chryseobacterium sp. kr6 strain shows high extracellular keratinases production, suggesting potential for bioconversion of keratinous substrates. The present work had as main objective to purify and immobilize a keratinase from Chryseobacterium sp. kr6. The optimal conditions for proteolytic activity were established with aid of experimental design and response surface methodology. The results demonstrated that the best conditions were at pH range of 7.4 to 9.2, 35°C to 50°C and NaCl concentration from 50 to 340 mmol L-1. Keratinase specificity for various substrates also was investigated, suggesting that the enzyme had preference for hydrophobic and positively charged residues. The keratinase purification involved precipitation with ammonium sulphate and chromatographic techniques of gel permeation and anionic exchange. The final sample obtained after the purification steps presents a purification factor of 40.2-fold and specific activity of 21,466 U mg-1 of protein. The molecular weight of the enzyme, determined by SDS-PAGE, was around 20 kDa. The kinetics and thermodynamics parameters for thermal keratinase inactivation, under different conditions, were estimated. From results, it was possible to observe that the calcium affect significantly the thermal stability of the enzyme. Comparing with the control samples, the half-life time of the purified enzyme with calcium increased about 7.3, 20.2 and 9.8-fold, at 50°C, 55°C and 60°C, respectively. The enzyme activity was significantly inhibited in the presence of EDTA and 1,10- phenanthroline, suggesting that the enzyme belongs to metalloprotease group. The developing of a chitosan support for covalent immobilization of the purified keratinase was investigated. The effects of different glutaraldehyde concentrations, as well as, the activation time required for the chitosan beads on the enzyme immobilization were investigated. The optimal conditions for enzyme immobilization were at glutaraldehyde concentration ranging from 34 to 56 g L-1 and activation time of 6 to 10 h. Under these conditions, above 80% of added enzyme was covalently immobilized on the support. From the best conditions, indicated by response surface methodology, the load capacity of the macrospheres was estimated, being of 58.8 U g-1. The immobilized enzyme presented higher thermal stability when compared with free one, besides it retained 63,4% of the initial enzyme activity after five cicles of reuse.
6

Purificação e imobilização de uma protease queratinolítica produzida por Chryseobacterium sp. linhagem Kr6 / Purification and immobilization of a protease keratinolytic from Chryseobacterium sp. strain kr6

Silveira, Silvana Terra January 2009 (has links)
Queratinases (E.C. 3.4.21/24/99.11) são um grupo de enzimas proteolíticas que catalisam a hidrólise da queratina. A linhagem queratinolítica Chryseobacterium sp. kr6 apresenta elevada produção de queratinases extracelulares, demonstrando potencial para bioconversão de substratos constituídos por queratina. O presente trabalho teve como principal objetivo purificar e imobilizar uma queratinase produzida pelo Chryseobacterium sp. kr6. As condições ótimas para a atividade proteolítica da queratinase foram estabelecidas com o auxílo das ferramentas estatísticas de planejamento experimental e superfície de resposta. Os resultados demonstraram que tais condições foram atingidas ao utilizar pH na faixa de 7,4 a 9,2, 35°C a 50°C e concentração de NaCl de 50 a 340 mmol L-1. A especificidade da queratinase frente a diferentes substratos também foi investigada, indicando a preferência da enzima por resíduos hidrofóbicos ou positivamente carregados. A completa purificação da queratinase envolveu a precipitação com sulfato de amônio, cromatografias de permeação em gel e troca aniônica. A amostra obtida após as referidas etapas apresentou um fator de purificação de 40,2 vezes e atividade específica de 21.466 U mg-1 de proteína. A massa molecular da enzima, determinada por SDS-PAGE, foi, de aproximadamente, 20 kDa. Os parâmetros cinéticos e termodinâmicos para a inativação térmica da queratinase, sob diferentes condições, foram estimados. A partir dos resultados obtidos, observou-se que a presença de cálcio aumenta significativamente a estabilidade térmica da enzima. Comparando com as amostras controles, o tempo de meia vida da enzima purificada na presença de Ca2+ aumentou 7,3, 20,2 e 9,8 vezes, a 50°C, 55°C e 60ºC, respectivamente. A atividade enzimática foi significativamente inibida na presença de EDTA e 1,10-fenantrolina, sugerindo se tratar de uma metaloprotease. O desenvolvimento de um suporte a base de quitosana para a imobilização covalente da queratinase purificada foi investigado. Para isso, foram avaliados os efeitos de diferentes concentrações de glutaraldeído e tempo de contato deste com as esferas de quitosana, sobre o percentual de imobilização da enzima. Os melhores resultados obtidos para a imobilização da queratinase ao suporte foram ao utilizar concentração de glutaraldeído na faixa de 34 a 56 g L-1 e um período de ativação das esferas na faixa de 6 a 10 h. Sob tais condições, obteve-se 80% de imobilização da enzima. A partir das condições ótimas para a imobilização da enzima ao suporte, apontadas pela metodologia de superfície de resposta, estimou-se a capacidade de carga máxima do suporte, sendo esta de 58,8 U g-1. A enzima imobilizada apresentou maior estabilidade térmica quando comparada com a forma livre, além de reter 63,4% da atividade enzimática inicial após cinco reutilizações. / Keratinases (E.C. 3.4.21/24/99.11) are a group of proteolytic enzymes that are able to catalize the keratin hydrolysis. The keratinolytic Chryseobacterium sp. kr6 strain shows high extracellular keratinases production, suggesting potential for bioconversion of keratinous substrates. The present work had as main objective to purify and immobilize a keratinase from Chryseobacterium sp. kr6. The optimal conditions for proteolytic activity were established with aid of experimental design and response surface methodology. The results demonstrated that the best conditions were at pH range of 7.4 to 9.2, 35°C to 50°C and NaCl concentration from 50 to 340 mmol L-1. Keratinase specificity for various substrates also was investigated, suggesting that the enzyme had preference for hydrophobic and positively charged residues. The keratinase purification involved precipitation with ammonium sulphate and chromatographic techniques of gel permeation and anionic exchange. The final sample obtained after the purification steps presents a purification factor of 40.2-fold and specific activity of 21,466 U mg-1 of protein. The molecular weight of the enzyme, determined by SDS-PAGE, was around 20 kDa. The kinetics and thermodynamics parameters for thermal keratinase inactivation, under different conditions, were estimated. From results, it was possible to observe that the calcium affect significantly the thermal stability of the enzyme. Comparing with the control samples, the half-life time of the purified enzyme with calcium increased about 7.3, 20.2 and 9.8-fold, at 50°C, 55°C and 60°C, respectively. The enzyme activity was significantly inhibited in the presence of EDTA and 1,10- phenanthroline, suggesting that the enzyme belongs to metalloprotease group. The developing of a chitosan support for covalent immobilization of the purified keratinase was investigated. The effects of different glutaraldehyde concentrations, as well as, the activation time required for the chitosan beads on the enzyme immobilization were investigated. The optimal conditions for enzyme immobilization were at glutaraldehyde concentration ranging from 34 to 56 g L-1 and activation time of 6 to 10 h. Under these conditions, above 80% of added enzyme was covalently immobilized on the support. From the best conditions, indicated by response surface methodology, the load capacity of the macrospheres was estimated, being of 58.8 U g-1. The immobilized enzyme presented higher thermal stability when compared with free one, besides it retained 63,4% of the initial enzyme activity after five cicles of reuse.
7

Produção e caracterização de pigmentos produzidos por Chryseobacterium KR6 e Lysobacter A03 / Production and characterization of pigments produced by Crhyseobacterium KR6 e Lysobacter A03

Pailliè Jiménez, Maria Elisa January 2017 (has links)
O uso de pigmentos bacterianos com potencial biotecnológico avança cada vez mais e a partir dessa fonte natural são desenvolvidos diversos produtos com diferentes aplicações em indústrias farmacêuticas, de alimentos, cosmética entre outras, apresentando vantagens em questões econômicas e ambientais, cumprindo com a demanda e trazendo benefícios para a saúde dos consumidores e reduzindo o uso de produtos de síntese química. O objetivo desse trabalho foi a produção, ao nível de laboratório, e caracterização de pigmentos sintetizados pelas bactérias Chryseobacterium KR6 e Lysobacter A03 isoladas de penas de frango e penas de pinguim, respectivamente. Os pigmentos estudados neste trabalho, extraídos das duas linhagens, resultaram ser pigmentos do tipo Flexirubina (DAR) o que foi revelado pelo teste positivo de KOH 20% e os espectros de UV-vis, e provavelmente Xanthomonadina (APE-DAR hibrido), respetivamente. Os dois pigmentos apresentaram atividade antioxidante avaliado pela captura do radical ABTS. Não foi possível propor uma estrutura química para os dois pigmentos, processos de purificação são requeridos para a identificação molecular desses pigmentos biotecnologicamente viáveis. / The use of bacterial pigments with biotechnological potential advances are growing and more and from this natural source are developed several products with different applications in the pharmaceutical, food, cosmetics and other industries, presenting advantages in economic and environmental issues, fulfilling a demand and bringing benefits For consumer health and reducing the use of chemical synthetized products. The aim of this study was the production, working volume and characterization of pigments synthesized by Chryseobacterium KR6 and Lysobacter A03 bacteria isolated from chicken and penguin feathers, respectively. The pigments were characterized by KOH 20% test, UV-visible, colors system CIELAB, HPLC-DAD-MS, FTIR and was evaluated the antioxidant capacity. The pigments from KR6 and A03 presents some characteristics from flexirubin and xanthomonadin non- brominated type pigments respectively. Pigment from KR6 shows a positive bathochromic shift when colonies or the extracted pigment are in presence of alkaline solution (KOH20%) and also have a λmax at 450nm in acetone when analyzed by UV-Vis. The FTIR analysis shows some principal functional groups that might be from a flexirubin molecule. Pigment from A03 didn’t present any shift when flooded with KOH and the λmax was 419 nm and 427 nm in acetone and chloroform respectively. The two pigments presented antioxidant activity evaluated by the capture of the free radical ABTS. It was not possible to propose a chemical structure for the two pigments; purification processes are necessary for a molecular identification of the biotechnologically viable pigments.
8

Produção e caracterização de pigmentos produzidos por Chryseobacterium KR6 e Lysobacter A03 / Production and characterization of pigments produced by Crhyseobacterium KR6 e Lysobacter A03

Pailliè Jiménez, Maria Elisa January 2017 (has links)
O uso de pigmentos bacterianos com potencial biotecnológico avança cada vez mais e a partir dessa fonte natural são desenvolvidos diversos produtos com diferentes aplicações em indústrias farmacêuticas, de alimentos, cosmética entre outras, apresentando vantagens em questões econômicas e ambientais, cumprindo com a demanda e trazendo benefícios para a saúde dos consumidores e reduzindo o uso de produtos de síntese química. O objetivo desse trabalho foi a produção, ao nível de laboratório, e caracterização de pigmentos sintetizados pelas bactérias Chryseobacterium KR6 e Lysobacter A03 isoladas de penas de frango e penas de pinguim, respectivamente. Os pigmentos estudados neste trabalho, extraídos das duas linhagens, resultaram ser pigmentos do tipo Flexirubina (DAR) o que foi revelado pelo teste positivo de KOH 20% e os espectros de UV-vis, e provavelmente Xanthomonadina (APE-DAR hibrido), respetivamente. Os dois pigmentos apresentaram atividade antioxidante avaliado pela captura do radical ABTS. Não foi possível propor uma estrutura química para os dois pigmentos, processos de purificação são requeridos para a identificação molecular desses pigmentos biotecnologicamente viáveis. / The use of bacterial pigments with biotechnological potential advances are growing and more and from this natural source are developed several products with different applications in the pharmaceutical, food, cosmetics and other industries, presenting advantages in economic and environmental issues, fulfilling a demand and bringing benefits For consumer health and reducing the use of chemical synthetized products. The aim of this study was the production, working volume and characterization of pigments synthesized by Chryseobacterium KR6 and Lysobacter A03 bacteria isolated from chicken and penguin feathers, respectively. The pigments were characterized by KOH 20% test, UV-visible, colors system CIELAB, HPLC-DAD-MS, FTIR and was evaluated the antioxidant capacity. The pigments from KR6 and A03 presents some characteristics from flexirubin and xanthomonadin non- brominated type pigments respectively. Pigment from KR6 shows a positive bathochromic shift when colonies or the extracted pigment are in presence of alkaline solution (KOH20%) and also have a λmax at 450nm in acetone when analyzed by UV-Vis. The FTIR analysis shows some principal functional groups that might be from a flexirubin molecule. Pigment from A03 didn’t present any shift when flooded with KOH and the λmax was 419 nm and 427 nm in acetone and chloroform respectively. The two pigments presented antioxidant activity evaluated by the capture of the free radical ABTS. It was not possible to propose a chemical structure for the two pigments; purification processes are necessary for a molecular identification of the biotechnologically viable pigments.
9

Produção e caracterização de pigmentos produzidos por Chryseobacterium KR6 e Lysobacter A03 / Production and characterization of pigments produced by Crhyseobacterium KR6 e Lysobacter A03

Pailliè Jiménez, Maria Elisa January 2017 (has links)
O uso de pigmentos bacterianos com potencial biotecnológico avança cada vez mais e a partir dessa fonte natural são desenvolvidos diversos produtos com diferentes aplicações em indústrias farmacêuticas, de alimentos, cosmética entre outras, apresentando vantagens em questões econômicas e ambientais, cumprindo com a demanda e trazendo benefícios para a saúde dos consumidores e reduzindo o uso de produtos de síntese química. O objetivo desse trabalho foi a produção, ao nível de laboratório, e caracterização de pigmentos sintetizados pelas bactérias Chryseobacterium KR6 e Lysobacter A03 isoladas de penas de frango e penas de pinguim, respectivamente. Os pigmentos estudados neste trabalho, extraídos das duas linhagens, resultaram ser pigmentos do tipo Flexirubina (DAR) o que foi revelado pelo teste positivo de KOH 20% e os espectros de UV-vis, e provavelmente Xanthomonadina (APE-DAR hibrido), respetivamente. Os dois pigmentos apresentaram atividade antioxidante avaliado pela captura do radical ABTS. Não foi possível propor uma estrutura química para os dois pigmentos, processos de purificação são requeridos para a identificação molecular desses pigmentos biotecnologicamente viáveis. / The use of bacterial pigments with biotechnological potential advances are growing and more and from this natural source are developed several products with different applications in the pharmaceutical, food, cosmetics and other industries, presenting advantages in economic and environmental issues, fulfilling a demand and bringing benefits For consumer health and reducing the use of chemical synthetized products. The aim of this study was the production, working volume and characterization of pigments synthesized by Chryseobacterium KR6 and Lysobacter A03 bacteria isolated from chicken and penguin feathers, respectively. The pigments were characterized by KOH 20% test, UV-visible, colors system CIELAB, HPLC-DAD-MS, FTIR and was evaluated the antioxidant capacity. The pigments from KR6 and A03 presents some characteristics from flexirubin and xanthomonadin non- brominated type pigments respectively. Pigment from KR6 shows a positive bathochromic shift when colonies or the extracted pigment are in presence of alkaline solution (KOH20%) and also have a λmax at 450nm in acetone when analyzed by UV-Vis. The FTIR analysis shows some principal functional groups that might be from a flexirubin molecule. Pigment from A03 didn’t present any shift when flooded with KOH and the λmax was 419 nm and 427 nm in acetone and chloroform respectively. The two pigments presented antioxidant activity evaluated by the capture of the free radical ABTS. It was not possible to propose a chemical structure for the two pigments; purification processes are necessary for a molecular identification of the biotechnologically viable pigments.

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