Chitin in shrimp waste is tightly associated with proteins, lipids, pigments and mineral deposits. Therefore, these source materials have to be pretreated to remove these components. For a long time, chemical process has been used widely for extraction of chitin from shrimp waste. The chemical process however led to severe environmental damage and low chitin quality. The biological process has been shown promising to replace the harsh chemical process to reduce the environment impact. In our previous study chitin recovery from sterilized shrimp waste by Lactobacillus plantarum NCDN4 was investigated. However in large scale it is uneconomical to sterilize the shrimp waste. For that reason, in this study the microbial process using Lactobacillus plantarum NCDN4 for chitin recovery from unsterilezed shrimp waste has been investigated. Factors affecting the demineralization by this strain such as inoculum size, glucose concentration, initial pH, NaCl concentration and fermentation time were investigated. It was found that when unsterilized shrimp waste fermented with 20% L. plantarum inoculum, 12,5% glucose, and pH 6 for 4 days at 30oC, 99. 28% emineralization and 48.65% deproteination could be achieved. The ash and protein content of fermented residues were 1.33% and 22.46% respectively. Compared to sterilized condition the efficiency of demineralization and deproteination was similar. / Chitin trong phế liệu tôm liên kết chặt chẽ với protein, sắc tố và khoáng. Do vậy để thu được chitin cần có các bước tiền xử lí để loại các thành phần không phải chitin ra. Phương pháp hóa học được sử dụng rộng rãi từ lâu để tiền xử lí chitin. Tuy nhiên do phương pháp hóa học gây hại cho môi trường và tạo ra chitin chất lượng thấp, các nhà khoa học nỗ lực nghiên cứu tìm ra các phương pháp thay thế. Phương pháp sinh học được xem là rất khả quan để thay thế phương pháp hóa học. Trong nghiên cứu trước của chúng tôi, quá trình lên men phế liệu tôm thanh trùng bằng Lactobacillus plantarum NCDN4 đã được nghiên cứu. Tuy nhiên việc thanh trùng phế liệu tôm không kinh tế. Trong nghiên cứu này quá trình lên men phế liệu tôm không thanh trùng bằng Lactobacillus plantarum NCDN4 đã được khảo sát. Các yếu tố như tỷ lệ giống, nồng độ đường glucose, nồng độ NaCl, pH ban đầu của môi trường lên men và thời gian lên men đã được nghiên cứu. Kết quả cho thấy ở điều kiện 20% giống theo thể tích, 12,5% dịch đường glucose, 2% muối theo khối lượng, pH ban đầu 6, sau 5 ngày lên men lượng khoáng và protein trong nguyên liệu giảm tương ứng 99.28% và 48.65%. Lượng khoáng và protein còn lại tương ứng 1.33% và 22.46% (tính theo trọng lượng khô). So với phế liệu tôm không thanh trùng, hiệu quả loại khoáng và protein là tương đương.

Au cours de ce travail de thèse, nous nous sommes intéressés aux études taxonomiques des deux souches TN17 et Fr10 qui sont deux nouvelles espèces du genre Streptomyces dont nous avons proposé les nomenclatures suivantes : Streptomyces lilaceus sp. TN17 et Streptomyces microflavus sp. Fr10. A partir de la souche Streptomyces lilaceus sp. TN17, trois molécules on été purifiées et identifiées par le biais de plusieurs techniques spectroscopiques, il s’agit d’un dérivé de DKP (L-Leu, L-Arg), un dérivé de phtalate le di-(2-éthylhexyl) phtalate et un tértrapeptide cyclique : le 1 - [2 -(cyclopentanecarbonyl-3-phenylpropionyl] – pyrrolidine-2-carboxylique (1-carbamoyl-propyl)-amide. Ces trois molécules présentent des activités antibactériennes et antifongiques. Suite au criblage des souches de bactéries lactiques productrices de bactériocines de la collection de notre laboratoire et leurs caractérisations, nous avons identifié une nouvelle souche de Lactobacillus nommée Lactobacillus plantarum sp.TN635 qui produit une bactériocine « BacTN635 » de 3,8 KDa. Cette dernière a été purifiée à homogénéité, elle possède un spectre d’action très large contre les bactéries à Gram+, à Gram- et contre les champignons filamenteux et unicellulaires. BacTN635 a un effet bactéricide contre Listeria ivanovii BUG 496 et fongistatique contre Candida tropicalis R2 CIP203. / In This Thesis, we are interested in taxonomic studies of two strains TN17 and Fr10 which are two new species of the genus Streptomyces, and we have proposed the following names: Streptomyces lilaceus sp. TN17 and Streptomyces microflavus sp. Fr10. From Streptomyces lilaceus strain sp. TN17, three molecules have been purified and identified by means of several spectroscopic techniques, it is a derivative of DKP (L-Leu, Larg), a derivative of phthalate di-(2-ethylhexyl) phthalate and cyclic peptide 1 - [2 - (cyclopentanecarbonyl-3-phenylpropionyl] - pyrrolidine-2-carboxylic acid (1-carbamoylpropyl)- amide. All three molecules exhibit antibacterial and antifungal activities. A novel strain of lactic acid bacteria was isolated and characterized from a collection of our laboratory. It’s identified as a new strain of Lactobacillus, named Lactobacillus plantarum sp.TN635 producing a new bacteriocin "BacTN635" of 3.8 kDa, purified to homogeneity and spectrum with a very broad action against Gram + and Gram-, filamentous and unicellular fungi. BacTN635 has a bactericidal effect against Listeria ivanovii BUG 496 and fungistatic against Candida tropicalis R2 CIP203.

Bacteriocins are antimicrobial peptides ribosomally synthesized by various bacteria. In particular, the bacteriocins produced by lactic acid bacteria have recently received great attention due to their wide applicability and also because they are produced by microorganisms safe for human consumption. There are numerous studies reporting bacteriocin production by different lactic acid bacteria, as well as its optimization by using alternative substrate. Some of these studies point to milk/cheese whey as a potential low-cost source for the cultivation of lactic acid bacteria and the production of biocomposites, such as bacteriocins. Several researches refer to the production of bacteriocins, mainly nisin. On the other hand, the production of bacteriocins by Lactobacillus plantarum strains still limited. In this context, the present work first studied the growth and production of bacteriocin by L. plantarum strain ST16Pa when cultivated in Man, Rogosa and Sharpe (MRS) broth with and without inulin supplementation incubated under shaken and stationary conditions. The results indicated that this strain has higher growth when cultured in aerobiosis; however, the highest bacteriocin activity is obtained in stationary condition. The stability and partitioning of bacteriocin from the fermented MRS broth of L. plantarum ST16Pa in the PEG/NaPA/electrolytes aqueous two-phase systems was also studied. After 1 h in temperatures from 50 °C to 80 °C and pH from 3.0 to 8.0, the produced bacteriocin remained stable. In addition, the proposed partition system has proved to be an economical alternative for the recovery and purification of this biomolecule. Motivated by the trend in use industrial by products aiming the production of high value-added biocomposites, we investigated the performance of milk/cheese whey as alternative substrate for L. plantarum ST16Pa growth and for the production of antimicrobial biomolecules by this strain. For this purpose, the study was divided in two steps, being the first developed using whey powder supplemented according to the Plackett & Burman experimental design, with 12 trials and 4 central points. Although the proposed design was not the ideal statistical tool to optimize the bacteriocin ST16Pa production, through it was possible to obtain a formulation, which resulted in greater inhibition zones when compared with previous date reported by other authors using the same strain cultured in cheese whey. Later, still using L. plantarum strain ST16Pa, we investigated the production of bacteriocin and lactate in fresh cheese whey previously hydrolyzed by Flavourzyme or Lactozym. The cultures were optimized by supplementing this medium with different concentrations of soybean flour, which were incubated under aerobic and microaerophilic/anaerobic conditions. The highest values of bacteriocin activity (7,367.23 AU/mL) and lactate yield (Ylactate/lactose = 1.39 g/g) were obtained under anaerobic conditions using 10 g/L of soybean flour to supplement cheese whey prehydrolyzed with Flavourzyme during 3 h. Finally, the cell-free supernatant resulted from this cultivation was applied on the surfaces of chicken breast fillets artificially contaminated with Enterococcus faecium 711, showing biopreservative efficiency during 7 days of storage under refrigeration. / Bacteriocinas são peptídeos antimicrobianos sintetizados por diversas bactérias. Em particular, as bacteriocinas produzidas por bactérias ácido-láticas têm recebido crescente destaque devido sua ampla aplicabilidade e também por serem produzidas por microorganismos seguros para o consumo humano. Inúmeros estudos relatam a produção de bacteriocina por diversas bactérias ácido-láticas, bem como a otimização da produção desta biomolécula utilizando fontes alternativas de substrato. Alguns destes estudos apontam o soro de leite/queijo como uma fonte potencial e de baixo custo para o cultivo de bactérias láticas e produção de biocompostos, tais como bacteriocinas. Diversas pesquisas se referem à produção de bacteriocinas, principalmente a nisina. Por outro lado, a produção de bacteriocinas por cepas de Lactobacillus plantarum ainda é limitada. Neste âmbito, o presente trabalho estudou, primeiramente, o crescimento e produção de bacteriocina pela cepa L. plantarum ST16Pa quando cultivada em caldo Man, Rogosa e Sharpe (MRS) com e sem suplementação de inulina sob condições aeradas e sem agitação. Os resultados indicaram que este micro-organismo tem maior crescimento quando cultivado em aerobiose, entretanto, os maiores valores de atividade da bacteriocina produzida foram obtidos em cultivos não agitados. Ainda utilizando MRS para o cultivo desta cepa, investigou-se a estabilidade e partição da bacteriocina em sistema aquoso de duas fases do tipo PEG/NaPA/electrólitos. Após 1 h submetida à temperaturas entre 50 °C e 80 °C e pH entre 3,0 e 8,0, a bacteriocina produzida permaneceu estável. Além disso, o sistema de partição proposto demonstrou ser uma alternativa econômica para recuperação e purificação desta biomolécula. Motivados pela tendência do uso de subprodutos industriais para a produção de biocompostos de alto valor agregado, investigou-se o desempenho do soro de leite/queijo como substrato alternativo para o crescimento de L. plantarum ST16Pa e a consequente produção de biomoléculas antimicrobianas por esta cepa. O estudo foi divido em duas etapas, sendo a primeira desenvolvida utilizando soro de leite em pó suplementado de acordo com o delineamento experimental Plackett & Burman, com 12 ensaios e mais 4 pontos centrais. Embora o delineamento proposto não tenha sido a ferramenta estatística ideal para alcançar a otimização da produção de bacteriocina ST16Pa, através do mesmo foi possível obter uma formulação, a qual gerou maiores halos de inibição quando comparados com resultados prévios reportados por outros autores utilizando a mesma cepa cultivada em soro de queijo. Posteriormente, ainda utilizando L. plantarum ST16Pa, investigou-se a produção de bacteriocina e lactato em soro de queijo fresco previamente hidrolisado por Flavourzyme ou Lactozym. Os cultivos foram otimizado através da suplementação deste meio de cultura com diferentes concentrações de farinha de soja, os quais foram incubados sob condições aeróbicas e microaerofílicas/anaeróbicas. Os maiores valores de atividade da bacteriocina (7367,23 AU/mL) e rendimento de lactato (Ylactate/lactose = 1,39 g/g) foram obtidos sob condições anaeróbicas utilizando 10 g/L de farinha de soja para suplementar o soro de queijo hidrolizado por Flavourzyme durante 3 h. Por fim, o sobrenadante resultante deste cultivo foi aplicado sobre a superfície de filés de peito de frango artificialmente contaminados por Enterococcus faecium 711, demonstrando eficiência como bioconservante durante 7 dias de armazenamento sob refrigeração.

Bacteriocins are antimicrobial peptides ribosomally synthesized by various bacteria. In particular, the bacteriocins produced by lactic acid bacteria have recently received great attention due to their wide applicability and also because they are produced by microorganisms safe for human consumption. There are numerous studies reporting bacteriocin production by different lactic acid bacteria, as well as its optimization by using alternative substrate. Some of these studies point to milk/cheese whey as a potential low-cost source for the cultivation of lactic acid bacteria and the production of biocomposites, such as bacteriocins. Several researches refer to the production of bacteriocins, mainly nisin. On the other hand, the production of bacteriocins by Lactobacillus plantarum strains still limited. In this context, the present work first studied the growth and production of bacteriocin by L. plantarum strain ST16Pa when cultivated in Man, Rogosa and Sharpe (MRS) broth with and without inulin supplementation incubated under shaken and stationary conditions. The results indicated that this strain has higher growth when cultured in aerobiosis; however, the highest bacteriocin activity is obtained in stationary condition. The stability and partitioning of bacteriocin from the fermented MRS broth of L. plantarum ST16Pa in the PEG/NaPA/electrolytes aqueous two-phase systems was also studied. After 1 h in temperatures from 50 °C to 80 °C and pH from 3.0 to 8.0, the produced bacteriocin remained stable. In addition, the proposed partition system has proved to be an economical alternative for the recovery and purification of this biomolecule. Motivated by the trend in use industrial by products aiming the production of high value-added biocomposites, we investigated the performance of milk/cheese whey as alternative substrate for L. plantarum ST16Pa growth and for the production of antimicrobial biomolecules by this strain. For this purpose, the study was divided in two steps, being the first developed using whey powder supplemented according to the Plackett & Burman experimental design, with 12 trials and 4 central points. Although the proposed design was not the ideal statistical tool to optimize the bacteriocin ST16Pa production, through it was possible to obtain a formulation, which resulted in greater inhibition zones when compared with previous date reported by other authors using the same strain cultured in cheese whey. Later, still using L. plantarum strain ST16Pa, we investigated the production of bacteriocin and lactate in fresh cheese whey previously hydrolyzed by Flavourzyme or Lactozym. The cultures were optimized by supplementing this medium with different concentrations of soybean flour, which were incubated under aerobic and microaerophilic/anaerobic conditions. The highest values of bacteriocin activity (7,367.23 AU/mL) and lactate yield (Ylactate/lactose = 1.39 g/g) were obtained under anaerobic conditions using 10 g/L of soybean flour to supplement cheese whey prehydrolyzed with Flavourzyme during 3 h. Finally, the cell-free supernatant resulted from this cultivation was applied on the surfaces of chicken breast fillets artificially contaminated with Enterococcus faecium 711, showing biopreservative efficiency during 7 days of storage under refrigeration. / Bacteriocinas são peptídeos antimicrobianos sintetizados por diversas bactérias. Em particular, as bacteriocinas produzidas por bactérias ácido-láticas têm recebido crescente destaque devido sua ampla aplicabilidade e também por serem produzidas por microorganismos seguros para o consumo humano. Inúmeros estudos relatam a produção de bacteriocina por diversas bactérias ácido-láticas, bem como a otimização da produção desta biomolécula utilizando fontes alternativas de substrato. Alguns destes estudos apontam o soro de leite/queijo como uma fonte potencial e de baixo custo para o cultivo de bactérias láticas e produção de biocompostos, tais como bacteriocinas. Diversas pesquisas se referem à produção de bacteriocinas, principalmente a nisina. Por outro lado, a produção de bacteriocinas por cepas de Lactobacillus plantarum ainda é limitada. Neste âmbito, o presente trabalho estudou, primeiramente, o crescimento e produção de bacteriocina pela cepa L. plantarum ST16Pa quando cultivada em caldo Man, Rogosa e Sharpe (MRS) com e sem suplementação de inulina sob condições aeradas e sem agitação. Os resultados indicaram que este micro-organismo tem maior crescimento quando cultivado em aerobiose, entretanto, os maiores valores de atividade da bacteriocina produzida foram obtidos em cultivos não agitados. Ainda utilizando MRS para o cultivo desta cepa, investigou-se a estabilidade e partição da bacteriocina em sistema aquoso de duas fases do tipo PEG/NaPA/electrólitos. Após 1 h submetida à temperaturas entre 50 °C e 80 °C e pH entre 3,0 e 8,0, a bacteriocina produzida permaneceu estável. Além disso, o sistema de partição proposto demonstrou ser uma alternativa econômica para recuperação e purificação desta biomolécula. Motivados pela tendência do uso de subprodutos industriais para a produção de biocompostos de alto valor agregado, investigou-se o desempenho do soro de leite/queijo como substrato alternativo para o crescimento de L. plantarum ST16Pa e a consequente produção de biomoléculas antimicrobianas por esta cepa. O estudo foi divido em duas etapas, sendo a primeira desenvolvida utilizando soro de leite em pó suplementado de acordo com o delineamento experimental Plackett & Burman, com 12 ensaios e mais 4 pontos centrais. Embora o delineamento proposto não tenha sido a ferramenta estatística ideal para alcançar a otimização da produção de bacteriocina ST16Pa, através do mesmo foi possível obter uma formulação, a qual gerou maiores halos de inibição quando comparados com resultados prévios reportados por outros autores utilizando a mesma cepa cultivada em soro de queijo. Posteriormente, ainda utilizando L. plantarum ST16Pa, investigou-se a produção de bacteriocina e lactato em soro de queijo fresco previamente hidrolisado por Flavourzyme ou Lactozym. Os cultivos foram otimizado através da suplementação deste meio de cultura com diferentes concentrações de farinha de soja, os quais foram incubados sob condições aeróbicas e microaerofílicas/anaeróbicas. Os maiores valores de atividade da bacteriocina (7367,23 AU/mL) e rendimento de lactato (Ylactate/lactose = 1,39 g/g) foram obtidos sob condições anaeróbicas utilizando 10 g/L de farinha de soja para suplementar o soro de queijo hidrolizado por Flavourzyme durante 3 h. Por fim, o sobrenadante resultante deste cultivo foi aplicado sobre a superfície de filés de peito de frango artificialmente contaminados por Enterococcus faecium 711, demonstrando eficiência como bioconservante durante 7 dias de armazenamento sob refrigeração.

L’ocratossina e le ammine biogene sono due metaboliti biologici che possono essere ritrovati nei vini. Il primo di questi contaminanti è stato studiato recentemente per la sua elevata tossicità sebbene non sia rintracciabile frequentemente nei vini. Le ammine biogene sono presenti in ogni tipo di vino in differenti concentrazioni, oltretutto, alcune di loro, ad alte concentrazioni, possono causare reazioni allergiche. Gli obiettivi di questo PhD riguardano tre differenti aspetti. Indagare metodi biologici di per la decontaminazione di ocratossina A durante la vinificazione; in particolare lo studio si è focalizzato sull’uso di un ceppo Lactobacillus plantarum utilizzato come starter malolattico. Valutare la presenza di Lactobacillus spp., isolati da mosto e vino, in grado di produrre ammine biogene, usando tecniche molecolari come la reazione a catena della polimerasi (PCR) per rilevare i geni codificanti gli enzimi responsabili della sintesi di questi composti. Testare la capacità di un L. plantarum di effettuare la malolattica effettuando l’inoculo in differenti fasi della vinificazione e valutare il trend delle ammine biogene già presenti nel mosto. / Two of the major biological metabolites present in wine are the ochratoxin and the biogenic amines. The first of these contaminants was studied in recent decades because of its toxicity in humans, although its presence is not frequent in wines. The biogenic amines are present in every types of wine in different concentration, and some of them, in high concentrations, can cause allergenic reactions in humans. The objectives of this PhD regard three different aspects. Investigate the biological methods to reduce ochratoxin A in wine during winemaking; in particular the study is focused to use a Lactobacillus plantarum strain as malolactic starter. Investigate the presence of Lactobacillus spp., isolated from must and wine, able to produce the amines, using molecular techniques as polymerase chain reaction (PCR) to detect the genes that encode for the enzymes responsible of the synthesis of these compounds. Test the ability of a L. plantarum to perform MLF in relationship with inoculation time and assess the trend of biogenic amines already present in must.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to encapsulate probiotic microorganisms, evaluating their resistance against harsh environments and the use in dry fermented sausages. L. plantarum ATCC 8041 and E. faecium ATCC 700221 were encapsulate in alginate beads in association with inulin, milk powder and trehalose through extrusion technique and submitted to stressful environments such as high temperatures, high concentrations of sodium chloride and sodium nitrite and refrigerated storage period. Subsequently, L. plantarum was added to dry fermented sausages as free cells or encapsulated using extrusion, emulsion and double emulsion techniques. Encapsulation was effective to protect probiotics against stress treatments, mainly 70 ºC temperature and high concentrations of sodium chloride and sodium nitrite. Furthermore, encapsulated probiotics kept their viability throughout 70 days of refrigerated storage. In addition, the use of encapsulated L. plantarum did not change physico-chemical properties of dry fermented sausage during processing and storage. However, the extrusion technique seems to be more effective to keep higher counts of L. plantarum in dry fermented sausages during processing and storage. The addition of L. plantarum encapsulated in emulsion and double emulsion increased lipid oxidation in dry fermented sausages. Furtermore, in sensory analysis, dry fermented sausages containing L. plantarum encapsulated in emulsion had lower scores than control treatment in flavor, hardness, texture and overall acceptance attributes. / Este trabalho teve por objetivo encapsular microrganismos probióticos, avaliar sua resistência frente à condições adversas de processamento e estudar a aplicação em embutido cárneo fermentado. Para isso o L. plantarum ATCC 8041 e E. faecium ATCC 700221 foram encapsulados através da técnica de extrusão usando alginato de sódio juntamente com inulina, leite em pó e trealose como materiais de cápsula e submetidos à condições adversas de processamento como altas temperaturas, altas concentrações de cloreto de sódio e nitrito de sódio e armazenamento sob refrigeração. Posteriormente, o L. plantarum foi adicionado na forma livre e encapsulado através das técnicas de extrusão, emulsão simples e emulsão dupla em embutido fermentado e avaliado durante seu processamento e armazenamento. Observou-se que a encapsulação foi eficaz na proteção dos probióticos às condições adversas, especialmente quando submetidos à temperatura de 70 ºC e altas concentrações de cloreto e nitrito de sódio. Os probióticos encapsulados se mantiveram em níveis adequados durante os 70 dias de armazenamento sob refrigeração. Ainda, a adição de L. plantarum encapsulado por diferentes técnicas não alterou as características físico-químicas do embutido fermentado durante seu processamento e armazenamento. No entanto, a encapsulação através da técnica de extrusão se mostrou mais viável em manter as contagens de L. plantarum em níveis mais elevados no produto durante o processamento e armazenamento. A adição de L. plantarum encapsulado em emulsão simples e emulsão dupla aumentou a oxidação lipídica dos embutidos fermentados. Ainda, na análise sensorial, os produtos contendo L. plantarum encapsulado em emulsão simples apresentaram notas inferiores ao controle nos quesitos sabor, dureza, textura e aceitação geral.

Made available in DSpace on 2017-07-10T17:48:27Z (GMT). No. of bitstreams: 1 Marli_ Busanello.pdf: 709375 bytes, checksum: 60f50366eea2e98b3b71af83a9fd0ab6 (MD5) Previous issue date: 2011-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective was to evaluate the use oral probiotic of with viable cells and inactivated ("pool" of Lactobacillus sp. and Lactobacillus plantarum of gastrointestinal origin of pigs), on performance, intestinal microbiota and the immune system of piglets during the stages of lactation and creche. Were used, 108 lactating piglets and for nursery phase 72 piglets weaned at 21 days old, divided into an experimental design of randomized blocks with three treatments and six replicates. The treatments were: Treatment A: 1 ml of MRS broth + 1 ml of sterile saline, treatment B: 1 ml of probiotic (8.60 X 107 CFU/ml of a "pool" of Lactobacillus plantarum and Lactobacillus sp) activated MRS broth + 1 ml of saline, treatment C: 1 ml of probiotic inactivated cells in MRS broth + 1 ml of saline. Treatments were administered orally to piglets in the daily morning, from birth to 35 days of age with 1 ml per animal lactating and 2 ml in the nursery phase. The count of acidoláticas bacteria, and coliforms were not affected (P> 0.05) by treatments and sampling times. There was no effect (P>0.05) of treatments for weight gain and weight gain daily of piglets from birth to 21 days old. From 21 to 35 days of age was observed lower consumption and lower daily feed intake (P<0.05) for the control treatment when compared to the probiotic treatments and greater weight gain and weight daily gain (P<0.05) was observed in probiotic treatment with cells inactivated in relation to probiotic treatment with viable cells and control. There was less concentration (P<0.05) globulin in the treatment with probiotics compared to control. There were no significant differences (P>0.05) for the variables serum protein, albumin, glucose, hemoglobin, leukocytes, hematocrit, red blood cells, eosinophils, sticks, segments, lymphocytes, monocytes, platelets and serum levels of IgA between treatments. It was concluded that oral use of probiotics with viable cells and inactivated did not alter microbial counts, the values of serum protein, albumin, glucose, blood count and IgA and use of probiotics with viable and inactivated cells diminished serum globulin / O objetivo foi avaliar o uso oral de probiótico com células viáveis e inativadas ( pool de Lactobacillus sp. e Lactobacillus plantarum de origem gastrointestinal de suínos), no desempenho, na microbiota intestinal e no sistema imune de leitões durante as fases de aleitamento e creche. Foram utilizados, na fase de aleitamento, 108 leitões e para a fase de creche 72 leitões desmamados aos 21 dias de idade, distribuídos em um delineamento experimental de blocos ao acaso, com três tratamentos e seis repetições. Os tratamentos foram: tratamento A: 1 ml de caldo MRS + 1 ml de solução salina estéril; tratamento B: 1 ml de probiótico (8,60 X 107 UFC/ml de um pool de Lactobacillus sp e Lactobacillus plantarum) ativadas no caldo MRS + 1 ml de solução salina; tratamento C: 1 ml de probiótico contendo células inativadas no caldo MRS + 1 ml de solução salina. Os tratamentos foram administrados via oral aos leitões diariamente no período da manhã, do nascimento aos 35 dias de idade sendo 1 ml por animal na fase de aleitamento e 2 ml na fase de creche. As contagens de bactérias acidoláticas e coliformes não foram influenciadas (P>0,05) pelos tratamentos e tempos de coleta. Não foi observado efeito (P>0,05) dos tratamentos para ganho de peso e ganho diário de peso dos leitões do nascimento aos 21 dias de idade. Dos 21 aos 35 dias de idade observou-se para o tratamento controle menor consumo e menor consumo diário de ração (P<0,05) quando comparado aos tratamentos probióticos e maior ganho de peso e ganho diário de peso (P<0,05) foi observado no tratamento probiótico com células inativadas em relação ao tratamento probiótico com células viáveis e o controle. Observou-se menor concentração (P<0,05) de globulina nos tratamentos com probióticos em relação ao controle. Não foram observadas diferenças significativas (P>0,05) para as variáveis proteínas séricas totais, albumina, glicose, hemoglobina, leucócitos, hematócrito, hemácias, eosinófilos, bastões, segmentados, linfócitos, monócitos, plaquetas e para os níveis séricos de IgA entre os tratamentos. Concluiu-se que o uso oral de probiótico com células viáveis e inativadas não alterou as contagens microbiológicas, os valores das proteínas séricas totais, albumina, glicose, hemograma e IgA e uso de probióticos com células viáveis e inativadas diminuiu os níveis séricos de globulina

Chitin in shrimp waste is tightly associated with proteins, lipids, pigments and mineral deposits. Therefore, these source materials have to be pretreated to remove these components. For a long time, chemical process has been used widely for extraction of chitin from shrimp waste. The chemical process however led to severe environmental damage and low chitin quality. The biological process has been shown promising to replace the harsh chemical process to reduce the environment impact. In our previous study chitin recovery from sterilized shrimp waste by Lactobacillus plantarum NCDN4 was investigated. However in large scale it is uneconomical to sterilize the shrimp waste. For that reason, in this study the microbial process using Lactobacillus plantarum NCDN4 for chitin recovery from unsterilezed shrimp waste has been investigated. Factors affecting the demineralization by this strain such as inoculum size, glucose concentration, initial pH, NaCl concentration and fermentation time were investigated. It was found that when unsterilized shrimp waste fermented with 20% L. plantarum inoculum, 12,5% glucose, and pH 6 for 4 days at 30oC, 99. 28% emineralization and 48.65% deproteination could be achieved. The ash and protein content of fermented residues were 1.33% and 22.46% respectively. Compared to sterilized condition the efficiency of demineralization and deproteination was similar. / Chitin trong phế liệu tôm liên kết chặt chẽ với protein, sắc tố và khoáng. Do vậy để thu được chitin cần có các bước tiền xử lí để loại các thành phần không phải chitin ra. Phương pháp hóa học được sử dụng rộng rãi từ lâu để tiền xử lí chitin. Tuy nhiên do phương pháp hóa học gây hại cho môi trường và tạo ra chitin chất lượng thấp, các nhà khoa học nỗ lực nghiên cứu tìm ra các phương pháp thay thế. Phương pháp sinh học được xem là rất khả quan để thay thế phương pháp hóa học. Trong nghiên cứu trước của chúng tôi, quá trình lên men phế liệu tôm thanh trùng bằng Lactobacillus plantarum NCDN4 đã được nghiên cứu. Tuy nhiên việc thanh trùng phế liệu tôm không kinh tế. Trong nghiên cứu này quá trình lên men phế liệu tôm không thanh trùng bằng Lactobacillus plantarum NCDN4 đã được khảo sát. Các yếu tố như tỷ lệ giống, nồng độ đường glucose, nồng độ NaCl, pH ban đầu của môi trường lên men và thời gian lên men đã được nghiên cứu. Kết quả cho thấy ở điều kiện 20% giống theo thể tích, 12,5% dịch đường glucose, 2% muối theo khối lượng, pH ban đầu 6, sau 5 ngày lên men lượng khoáng và protein trong nguyên liệu giảm tương ứng 99.28% và 48.65%. Lượng khoáng và protein còn lại tương ứng 1.33% và 22.46% (tính theo trọng lượng khô). So với phế liệu tôm không thanh trùng, hiệu quả loại khoáng và protein là tương đương.

Thesis (MSc) -- University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Lactic acid bacteria play an essential role in the majority of fermented foods by producing organoleptic compounds and increasing the shelf life. The best-studied antimicrobial compounds are bacteriocins, i.e. ribosomally synthesized peptides. Most of these peptides have a narrow spectrum of activity and are usually only active against bacteria from the same ecological niche. The fact that all bacteriocins are degraded by proteolytic enzymes enlarges their potential use as natural food preservatives. The ideal would be to replace or reduce chemical preservatives such as sulfur dioxide, nitrates and nitrites. Bacteriocins are classified into four groups according to their structural and functional characteristics. Plantaricin 423, produced by Lactobacillus plantarum 423, is heat stable, plasmid encoded, relatively small (3.5 kDa) and is classified as a class Iia bacteriocin. The peptide is active from pH 1.0 to 10.0 and inhibits Gram-positive bacteria, including Lactobacillus spp., Leuconostoc spp., Oenococcus oeni, Pediococcus spp., Enterococcus spp., Propionibacterium spp. and pathogens such as Bacillus cereus, Clostridium spp. and Listeria monocytogenes. Production of bacteriocins may occur constitutively or may be regulated by a cell-density dependent system called quorum sensing. Plantaricin 423 is produced throughout logarithmic growth, with no apparent change in production levels when the producer strain is cultured in the presence of plantaricin 423 or Listeria innocua and Lactobacillus sakei. This led us to believe that plantaricin 423 may be produced constitutively. A reporter system was constructed which consisted of the plantaricin 423 promoter, P423, fused to the luxAB genes and cloned into a shuttle vector, pTRKH2. The newly constructed plasmid, pTAB4, was transformed to a bacteriocin-negative mutant of L. plantarum (423 B} Despite several repeats, no luciferase activity was recorded and no RNA homologous to the luxAB genes was detected. The region necessary for expression of plantaricin 423 may be located stream-up of the -80 region homologous to the -80 and -40 conserved repeats of regulated class II bacteriocins. Inclusion of the latter region in the reporter construct may result in the successful expression of luxAB. / AFRIKAANSE OPSOMMING: Melksuurbakteriee speel 'n belangrike rol in die meeste gefermenteerde voedselsoorte deur die produksie van organoleptiese komponente en die verlenging van rakleeftyd. Van aile antimikrobiese komponente is bakteriosiene (ribosomaal gesintetiseerde peptiede) die beste bestudeer. Hierdie peptiede het gewoonlik 'n nou spektrum van antimikrobiese werking en is meestal aktief teen bakteriee in dieselfde ekologiese nis. Die feit dat bakteriosiene deur proteolitiese ensieme in die spysverteringskanaal vernietig word, verhoog die potensiele gebruik van bakteriosiene as preserveermiddels. Die ideaal sal wees om die konsentrasie van chemiese preserveermiddels soos swaweldioksied, nitrate en nitriete te verlaag of rnoontlik te vervang met bakteriosiene. Bakteriosiene word in vier groepe op grond van hul strukturele en funksionele karaktereienskappe geklassifiseer. Plantarisien 423, geproduseer deur Lactobacillus plantarum 423, is hitte-stabiel, word deur 'n plasmied gekodeer, is relatief klein (3.5 kDa) en sorteer onder die klas Iia bakteriosiene. Die peptied is aktief oor 'n wye pH-reeks (pH 1.0-10.0) en inhibeer Gram-positiewe bakteriee, insluitend Lactobacillus spp., Leuconostoc spp., Oenococcus oeni, Pediococcus spp., Enterococcus spp., Propionibacterium spp. en patogene soos Bacillus cereus, Clostridium spp. en Listeria monocytogenes. Produksie van bakteriosiene kan konstitutief plaasvind of kan gereguleer word deur 'n seldigtheids- afhanklike sisteem naamlik "quorum sensing". Plantarisien 423 word regdeur logaritmiese groei geproduseer, met geen verandering in produksievlakke wanneer die produserende stam in die teenwoordigheid van plantarisien 423 of Listeria innocua en Lactobacillus sakei gekweek word nie. Dit het gelei tot die hipotese dat plantarisien 423 moontlik konstitutief geproduseer word. 'n Verklikkersisteem bestaande uit 'n fusie van die plantarisien 423 promoter, P423, aan die luxAB gene is gekonstrueer en in die pendelplasmied pTRKH2 gekloneer. Die nuutgekonstrueerde plasmied, pTAB4, is na 'n bakteriosien-negatiewe mutant van L. plantarum (stam 423 B-) getransfonneer. Ten spyte van etlike herhalings kon geen lusiferase-aktiwiteit opgespoor word nie en kon ook geen homologie in die RNA met die luxAB gene opgespoor word nie. Dit is moontlik dat die area nodig vir uitdrukking van plantarisien 423 verder stroom-op van die -80 area, homoloog aan die -80 en -40 gekonserveerde herhalings van reguleerbare klas II bakteriosiene, gesetel is. Insluiting van laasgenoemde area in die verklikker-konstruk mag lei tot die suksesvolle uitdrukking van luxAB.

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Background: Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) disorder. GI symptoms and impaired quality of life affect between 10-20% of all adults, corresponding to about 25-50% of all patients who visit a gastroenterologist’s clinic. In recent years, several novel mechanisms of IBS that likely relate to previously established theories have been identified. Inflammation, postinfectious low-grade inflammation, immunological and genetic predisposition along with altered microbiota are critical in IBS development, while several dietary factors may also play a role in this syndrome. However, none of these factors accounts for the full repertoire of IBS symptoms, and the pathophysiology of this condition is not fully understood. The overarching aim of this study was to investigate the nutrient intakes, GI microbiota and the effect of Lactobacillus plantarum (L.plantarum) 299v in IBS patients. Sub-aims: 1) Update healthcare professionals on current probiotic information and provide an overview of probiotic treatment approaches, with special emphasis on IBS, 2) conduct a well designed randomised, double blind, placebo-controlled trial (RCT) with L. plantarum 299v as part of an intervention and establish whether a course of probiotics may alleviate undesirable symptoms of IBS and improve quality of life, 3) assess nutrient intake in patients with irritable bowel syndrome (IBS) compared to dietary recommendations, 4) validate and assess the reproducibility of food records and 5) identify possible nutrient risk components for establishing GI microbiota involved in IBS and as part of an intervention, determine whether a course of probiotics may alter stool microbiota. Results: 1) A review article published by the author provides an overview of current probiotic treatment options to health care professionals and indicates certain probiotics are a promising therapeutic treatment option for management of IBS symtpoms, 2) the effects of the single strain probiotic, L. plantarum 299v, supplementation was evaluated in a RCT. Compared to placebo, the probiotic supplementation showed no significant reduction in GI symptom severity scores, particularly abdominal pain relief. Quality of life was also not improved in the treatment versus control group. Both the treatment and placebo groups improved significantly over the trial period, indicating a large placebo effect, 3) nutrient intakes of the IBS patients compared to current dietary reference recommendations indicates that this group of patients are at risk for nutrient inadequacies in key macro and micronutrients, 4) the validity and reliability of the dietary data showed good reliability but poor validity as measured by plasma fatty acids and 5) the GI microbiota composition in the phenotypically different diarrhoea-predominant IBS (D-IBS) vs. constipation-predominant IBS (C-IBS) showed that D-IBS patients had significantly lower counts of Lactobacillus plantarum compared to C-IBS patients. The probiotic had no significant effects on the GI microbiota as measured by quantitative polymerase chain reaction (qPCR). It was found that nutrient intakes had a significant impact on the microbiota. Lower fibre intakes were associated with higher Bacteroides spp., lower Bifidobacteria bifidum and Lactobacillus plantarum counts in both IBS groups. Conclusion: Taken together, L.plantarum 299v did not alleviate the GI symptoms of IBS, nor was it associated with significant changes in the GI microbiota. IBS patients may be at risk of key nutrient inadequacies. The influence of nutrient intakes on the GI microbiota provides an attractive explanation as a potential pathophysiological factor for IBS. / AFRIKAANSE OPSOMMING: Agtergrond: Prikkelbare derm-sindroom (PDS) is ‘n algemene gastro-intestinale (GI) stoornis. GI simptome affekteer die lewenskwaliteit van 10-20% van alle volwassenes. Dit stem ooreen met ongeveer 25-50% van alle pasiënte wat ‘n gastroënteroloog konsulteer. Verskeie oorspronklike meganismes vir die ontwikkeling van PDS is onlangs identifiseer. Inflammasie, post-infektiewe lae-graadse inflammasie, immunologiese en genetiese vatbaarheid tesame met veranderde mikrobiota is krities vir die ontwikkeling van PDS. Sekere dieetfaktore mag ook bydraend wees tot hierdie sindroom. Geen van hierdie faktore is egter verantwoordelik vir die volle spektrum van PDS simptome nie en die patofisiologie van die toestand word ook nog nie ten volle verstaan nie. Die oorkoepelende doel van hierdie studie is om nutriëntinname, GI mikrobiota en die uitwerking van L.plantarum 299v in PDS pasiënte bepaal. Sub-doelwitte: 1) Om gesondheidswerkers in te lig aangaande die nuutste inligting oor probiotika en om ‘n oorsig van probiotika behandelingsopsies te verskaf, met spesiale klem op PDS, 2) om ‘n goed beplande ewekansige, dubbel-blinde, plasebo-beheerde kliniese studie met L.plantarum 299v as deel van die intervensie uit te voer om sodoende te bepaal of ‘n kursus probiotika ongewensde simptome van PDS kan verbeter en lewenskwaliteit sodoende verhoog, 3) om nutriëntinname in pasiënte met PDS te bepaal vergeleke met dieet aanbevelings, 4) om die geldigheid en herhaalbaarheid van voedselrekords te bepaal en 5) om moontlike nutriënt risikokomponente vir die ontwikkeling van GI mikrobiota betrokke in PDS te identifiseer en om as deel van ‘n intervensie te bepaal of ‘n kursus probiotika stoelgang mikrobiota patrone verander. Resultate: 1) ‘n Oorsigartikel gepubliseer deur die kandidaat dui probiotika aan as ‘n belowende terapeutiese opsie in die behandeling van PDS simptome, 2) die effek van ‘n enkelstam probiotikum, L.plantarum 299v, is evalueer deur ‘n ewekansige, dubbel-blinde, plasebo-beheerde kliniese studie. Vergeleke met die plasebo, het probiotiese aanvulling geen betekenisvolle vermindering in die GI simptome in PDS pasiënte tot gevolg gehad nie. Lewenskwaliteit het ook nie verbeter in die behandelde versus die kontrole groep nie. Beide die behandelde en plasebo groepe het aansienlik verbeter oor die studietydperk, wat ‘n groot plasebo effek aandui, 3) nutriëntinname van die PDS groep vergeleke met huidige dieetaanbevelings, dui daarop dat hierdie groep pasiënte ‘n risiko het vir die ontwikkeling van kern nutriënttekorte (makro- en mikronutriënte), 4) die geldigheid en betroubaarheid van die dieetdata dui op goeie betroubaarheid, maar swak geldigheid soos bepaal deur plasma vetsure en 5) die dermkanaal mikrobiotiese samestelling in die verskillende fenotipes, diarree-oorheersende PDS (D-PDS) vs. konstipasie-oorheersende PDS (K-PDS) dui daarop dat D-PDS pasiënte aansienlike minder Lactobacillus plantarum gehad het vergeleke met K-PDS pasiënte. Die probiotikum het geen beduidende uitwerking op die oorheersende mikrobiota gehad nie, soos gemeet deur kwantitatiewe polimerase kettingreaksie (kPKR). Daar is gevind dat dieet ‘n beduidende impak op die mikrobiota gehad het. Daar is ‘n verband tussen laer vesel inname en hoёr Bacteroides spp. en laer Bifidobacteria bididum en Lactobacillus plantarum tellings gevind in beide PDS groepe. Gevolgtrekking: Die L.plantarum 299v enkelstam probiotikum het nie die gastrointestinale simptome van PDS pasiënte verlig nie en daar is ook geen beduidende veranderinge in die mikrobiota gevind nie. PDS pasiënte mag ‘n verhoogde risiko toon vir kern nutriënttekorte. Die invloed van nutriëntinname op GI mikrobiota verskaf ‘n belowende verduideliking as ‘n potensiële patofisiologiese faktor in PDS.