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No. of bitstreams: 3 Ata de defesa.jpg: 323992 bytes, checksum: 07db65a3446ffd679e88c4c15e7ca402 (MD5) CartaEncaminhamentoAutodepósito.pdf: 291328 bytes, checksum: 6b041928e3526b18982f978a05efcd43 (MD5) Cristiane Cunha Guimarães-DISSERTAÇÃO DE MESTRADO EM CIÊNCIA ANIMAL.pdf: 1526233 bytes, checksum: c79b2f93789c5784cb7aed7841056023 (MD5) Previous issue date: 2018-08-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to evaluate the potential for production of silage from the waste from the processing of the tambaqui, evaluating the chemical and nutritional characteristics and the same use in the diet of laying hens for light commercial verification of apparent digestibility and energy metabolism. Treatments for production of silage if differentiated as the amount of inoculum (pure cultures of Lactobacillus plantarum). In the digestibility assay were used 72 layers of White Hisex with 62 weeks of age. For the treatments are designed to control feed and the feed with inclusion of 5% of the residual biological silage tambaqui. The biological method for preparation of silage from the residue of tambaqui obtained positive results in the conservation of the residual mass in clamped all percentages of inoculum. During the evaluation of the centesimal composition of organic wet silage tambaqui residue, the treatments were no significant difference and remained close in relation to residue in natura. In the dehydration of the product held with 14 days of inoculation, the centesimal composition of the product in their treatments presented promising results. Treatment with 2,5% of inoculum excelled the other treatments with regard to nutritional parameters for use in feed of layers, showing concentration of crude protein (CP)-33,29%, lipídieo (L)-33,65% and minerals Ca-21,26 g/Kg-¹ and P-11,98 g/ Kg-¹. The dehydrated product with 35 days of inoculation also presented excellent results for analysis of centesimal composition. The inclusion of 5% biological silage of tambaqui on light commercial layer diet showed good performance in the metabolism of protein and lipid, can be considered as a protein food or energy for use in power layers. The preparation of organic fish silage becomes an alternative to the fishing industry, promoting a sustainable and profitable destination, waste generated during processing, with potential for use in animal feed. / O objetivo deste estudo foi avaliar o potencial de produção de silagem a partir dos resíduos provenientes do beneficiamento do tambaqui, avaliando as suas características químicas e nutricionais e uso da mesma na dieta de poedeiras comerciais leves para verificação da digestibilidade aparente e metabolização energética. Os tratamentos para produção do ensilado se diferenciaram quanto a quantidade de inóculo (culturas puras da bactéria Lactobacillus plantarum). No ensaio de digestibilidade foram utilizadas 72 poedeiras da linhagem Hisex White com 62 semanas de idade. Para os tratamentos foram elaboradas a ração controle e a ração com inclusão de 5% da silagem biológica de resíduo de tambaqui. O método biológico para elaboração de silagem a partir do resíduo de tambaqui obteve resultados positivos na conservação da massa residual ensilada, em todos os percentuais de inóculo avaliados. Durante a avaliação da composição centesimal da silagem biológica úmida de resíduo de tambaqui, os tratamentos mostraram-se sem diferença significativa e se mantiveram próximos em relação ao resíduo in natura. Na desidratação do produto realizada com 14 dias de inoculação, a composição centesimal do produto nos respectivos tratamentos apresentou resultados promissores. O tratamento com 2,5% de inóculo se destacou aos demais tratamentos quanto aos parâmetros nutricionais para uso na alimentação das poedeiras, apresentando concentração de proteína bruta (PB)-33,29%, lipídieo (L)-33,65% e minerais Ca-21,26 g/Kg-¹ e P-11,98 g/Kg-¹. O produto desidratado com 35 dias de inoculação também apresentou ótimos resultados para análise de composição centesimal. A inclusão de 5% da silagem biológico de resíduos de tambaqui na dieta de poedeiras comerciais leves apresentou bom desempenho na metabolização de proteína e lipídeo, podendo este ser considerado como um alimento proteico ou energético para fins de uso na alimentação de poedeiras. A elaboração da silagem biológica de pescado torna-se uma alternativa para a indústria pesqueira, promovendo um destino sustentável e lucrativo, aos resíduos gerados durante o processamento, com potencial para utilização na alimentação de animal.

Ce travail de thèse a permis de décrire la contamination importante des grains du café de (Coffea canephora variété robusta) par des moisissures au cours des traitements post récolte des cerises de café par la voie sèche, dans une zone tropicale humide. La stratégie d’échantillonnage mise en place à consister à faire des prélèvements durant deux années successives (2008 et 2009) sur des sites localisés dans les principales zones de production du café en Côte d’Ivoire. A partir de 31 échantillons de cerises, grains et coques de café, 218 souches sauvages de moisissures ont été isolées sur milieu Potato Dextrose Agar (PDA) et identifiées. Ces champignons filamenteux sont répartis comme suit : Aspergillus section Nigri (52%) ; Aspergillus verts (13%), Penicillium (10%), Mucor (16%), Fusarium (4%), autre (5%). Les Aspergillus section Nigri qui comptent le complexe Aspergillus niger agreggate et Aspergillus carbonarius représentent un peu plus de la moitié de la population fongique soit 52%, soit 30% en 2008 et 70% en 2009, de la flore fongique totale. Ce groupe a fait l’objet d’une caractérisation morphologique. L’étude du potentiel mycotoxinogène des Aspergillus section Nigri isolées du café robusta a démontré qu’en plus de l’OTA, certaines souches d’Aspergillus Nigri produiraient de l’aflatoxine. Cependant l’espèce Aspergillus carbonarius reste la plus ochratoxinogène (0,6 µg et 15µg d’OTA/g de milieu gélosé). En plus des moisissures 44 souches de bactéries lactiques (LAB) ont été isolées à partir de la pulpe fraîche de café. Les caractères morphologiques, biochimiques et culturaux ont été étudiés. L’identification moléculaire des bactéries a permis de les classer dans le groupe de Lactobacillus plantarum sp. Après un criblage orienté, deux souches de LAB avec un effet important d’inhibition de croissance des moisissures mycotoxinogènes ont été sélectionnées. Les deux souches de Lactobacillus plantarum ont démontré une activité antifongique contre les souches d’Aspergillus carbonarius hautement ochratoxinogènes. Par conséquent la prévention de la mycotoxinogenèse sur café robusta, pourrait passer par l’inhibition de la croissance de certaines moisissures ochratoxinogènes. Les résultats acquis au cours de ce travail de thèse serviront de base afin de poursuivre cette étude d’une part avec des essais in situ pour tester l’efficacité des LAB sélectionnées et d’autre part, rechercher les biomolécules actives contre la germination des spores contaminants naturels post récolte en particulier des cerises de café en Côte d’Ivoire et des fruits et légumes en général. / One of the objectives of this thesis was to describe the significant contamination of robusta coffee beans (Coffea canephora) by moulds during the post-harvest processing of coffee cherries in the dry process. The sampling strategy was to take samples for two consecutive years (2008 and 2009) from different areas of coffee production in Ivory Coast and on the other hand, from the same area but from coffee producers using different methods of drying of coffee beans. From 31 samples, 218 wild strains of fungi were isolated on Potato Dextrose Agar (PDA) media and identified. These filamentous fungi were as follows: black Aspergilli (52%); green Aspergilli (13%), Penicillium (10%), Mucor (16%), Fusarium (4%) and others (5%). The black Aspergilli were found to include Aspergillus niger and Aspergillus carbonarius representing 52% of the fungal population, with a proportion of 30% in 2008 and 70% in 2009 of the total fungal flora. This group was selected to study more about their mycotoxin production. Most strains grown on media and at specific incubation conditions, were capable of producing one or more kinds of mycotoxins. Analysis of mycotoxins from fungi isolated from less than a hundred robusta coffee showed that ochratoxin A (OTA) was not the only mycotoxin that may contaminate the robusta coffee in Ivory Coast. Indeed, several strains belonging to the species Aspergillus Nigri group had shown their ability to produce not only ochratoxin A but also aflatoxin. However, the species A. carbonarius remains as the most ochratoxigenic strain but it does not produce aflatoxin.In parallel to the isolation of fungi, 44 strains of lactic acid bacteria (LAB) were also isolated from fresh coffee cherries, harvested in Ivory Coast in 2009. The morphological, biochemical and growth characteristics were studied. Molecular identification of strains ranked them to be in the group of Lactobacillus plantarum sp. After a screening experiment, it was possible to select two strains of LAB with a significant effect of inhibiting fungal growth by producing mycotoxins. The two strains of Lactobacillus plantarum showed antifungal activity against strains of Aspergillus carbonarius which is highly ochratoxigenic. Therefore the prevention of mycotoxigenicity of robusta coffee, could be rised by inhibiting the growth of certain ochratoxigenic fungi. The results achieved in this thesis serve as a basis to continue the study on one hand with field trials to test the effectiveness of selected LAB on the other hand, look for active biomolecules against spore germination of contaminants especially the natural post-harvest coffee beans in Ivory Coast and fruits and vegetables in general.

Akamu is a lactic acid bacteria fermented cereal-based food that complements infant diets in most African countries. Uncontrolled fermentation increases the variability in quality and safety of akamu. This study was aimed at the controlled fermentation of akamu with selected lactic acid bacteria (LAB), investigation of the probiotic potential of the LAB and the effect of variation in production method on the product quality and sensory properties. PCR-DGGE analysis of traditional akamu samples revealed LAB community dominated by Lactobacillus fermentum, L. plantarum, L. delbrueckii subsp. bulgaricus and L. helveticus. Isolated yeasts were Candida tropicalis, C. albicans, Clavispora lusitaniae and Saccharomyces paradoxus. The isolated Lactobacillus plantarum strains (NGL5 and NGL7) fermented irradiated ground maize slurries and produced significant levels of lactic acid (>73 mmol L-1) and low pH ≤3.63 displaying inhibitory activity against Salmonella enterica serovar Enteritidis NCTC 5188, Escherichia coli 1077 (NCTC 11560), Bacillus cereus NCIMB 11925, Staphylococcus aureus NCTC 3750 and Listeria monocytogenes NCTC 7973 in MRS agar and E. coli 1077 in maize slurry fermentation. Viability of both strains of L. plantarum at pH 2 after 3 h was reduced from ≥8.26±0.05 to ≤4.94±0.49 Log10 CFU mL-1 while incubation in 0.3% bile allowed growth to 5.73±0.13 and 7.93±0.12 Log10 CFU mL-1 after 6 h for NGL5 and NGL7 respectively. Auto-aggregation of the L. plantarum strains at 37oC (≥25 after 5 h) correlated with adhesion to hydrocarbons (<15, 26, 33 and 64% for Hexane, Hexadecane, Ethyl acetate and Chloroform respectively). The strains failed to exhibit gelatinase or haemolytic activity but adhered to porcine mucin (OD403 nm ≥0.63 with viability ≥6.52 Log10 CFU mL-1) and Caco-2 cells (≥5.13 Log10 CFU mL-1). The ash, mineral (Ca, K, Mg, Na, S and Zn), IDF, SDFP and TDF content of the L. plantarum fermented ground maize slurries were significantly (p≤0.05) higher than that of the traditional akamu but the peak and final viscosities (139.5 and 68.5 cP respectively) were significantly (p≤0.05) the least. The aroma, appearance, colour, flavour and texture of the resultant porridges were liked moderately by 75% of the assessors. This study demonstrated that fermentation with the L. plantarum strains would contribute towards product safety and the L. plantarum strains possessed some probiotic potential that could be beneficial to the consumers particularly in those developing countries were the main staple foods are fermented cereals.

Thesis (PhD (Microbiology))--Stellenbosch University, 2008. / One of the key selection criteria for potential probiotics is the ability to adhere and colonise the host gastrointestinal tract (GIT). Probiotics compete for receptor sites at the host intestinal surface, preventing the colonisation of pathogens, thereby protecting the host from infection. In addition, several important intestinal functions are mediated by the binding of probiotics to host tissue. However, the molecular mechanisms and genotypic characterization of adhesive elements have not received as much attention as other aspects of probiotic research. The present study aims to contribute to this area of research. The first part of the study focused on monitoring the expression of mucus adhesion genes mub, mapA, adhesion-like factor EF-Tu and bacteriocin gene plaA of Lactobacillus plantarum 423, as well as mub, surface layer protein (slp) and EF-Tu of Lactobacillus acidophilus ATCC 4356 when grown in the presence of mucin, bile, pancreatin and at low pH. Real time PCR was used. mub, mapA and EF-Tu of strain 423 were up-regulated in the presence of mucus and expression increased under increasing concentrations of mucus. Expression of mapA was up-regulated under normal gut conditions (0.3%, w/v, bile; 0.3%, w/v, pancreatin; pH 6.5) and at higher levels of bile (1.0%, w/v) and pancreatin (1.0%, w/v). Expression of mub was downregulated in the presence of bile and pancreatin at pH 6.5, whilst the expression of EFTu and plaA remained unchanged. At pH 4.0, the expression of mub and mapA remained unchanged, whilst EF-Tu and plaA were up-regulated. Expression of mapA was down-regulated in the presence of 0.1% (w/v) cysteine, suggesting that the gene is regulated by a mechanism of transcription attenuation that involves cysteine. In the case of L. acidophilus ATCC 4356, none of the genes were up-regulated under increasing concentrations of mucin, whilst only slp and EF-Tu were up-regulated under normal and stressful gut conditions in vitro. In the second part of the study, male Wistar rats were used to evaluate which section of the gastrointestinal tract are colonised by L. plantarum 423 and Enterococcus mundtii ST4SA and determine the effect of adhesion. Fluorescent in situ hybridization (FISH) incorporating strain specific oilgonucleotide probes indicated strong fluorescent signals for L. plantarum 423 along the intestinal lining of the ileum and the cecum. L. plantarum 423 did not colonise the colon as indicated by real timePCR. Fluorescent signals were recorded for E. mundtii ST4SA across the epithelial barrier of cecum and colonic tissue, suggesting that translocation took place. Real time PCR revealed highest cell numbers of strain ST4SA in the cecum and the colon. Haemotoxylin eosin staining of rat tissue revealed no change in morphology or any toxic effects induced upon adhesion of the strains. 16S rDNA PCR and denaturing gradient gel electrophoresis (DGGE) revealed a decrease in enterobacterial species whilst the lactic acid bacterial content remained unchanged. Strains 423 and ST4SA agglutinated yeast cells in vitro, indicating the possible presence of mannose receptors. It is well known that these receptors play a crucial role in the elimination of type 1 fimbriated strains of E. coli. It is thus safe to speculate that mannose receptors may have played a role in diminishing the enterobacterial content in the gut. The third part of the study encompassed characterization of cell surface proteins of L. plantarum 423 and their role in adhesion to Caco-2 cell lines. The strain lacks the typical surface layer protein whilst a multifunctional “intracellular” protein, elongation factor Tu (EF-Tu) and glycolytic enzymes glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and triosephosphate isomerase (TPI) were detected. Removal of surface proteins reduced adherence of strain 423 to Caco-2 cell lines by 40%, suggesting that these proteins play a role in adhesion. The ability of strain 423 to competitively adhere, exclude and displace Clostridium sporogenes LMG 13570 and Enterococcus faecalis LMG 13566 from Caco-2 cell lines, was studied. Adhesion of C. sporogenes LMG 13570 and E. faecalis LMG 13566 was inhibited by 70% and 90%, respectively. Strain 423 excluded C. sporogenes LMG 13570 from Caco-2 cells by 73% and displaced the pathogen by 80%. E. faecalis LMG 13566 was excluded by 60% and displaced from Caco-2 cells by 90%. Despite removal of the surface proteins, L. plantarum 423 was still capable of competitively adhering to Caco-2 cells and reduced adherence of C. sporogenes LMG 13570 by 50% and E. faecalis LMG 13566 by 70%.

Os microrganismos probióticos são considerados suplementos alimentares vivos, apresentando benefícios ao hospedeiro e melhorando o balanço intestinal. A produção de Lactobacillus com alta densidade celular vem sendo estudada e possui grande interesse por parte da indústria, bem como o estudo de novos meios de cultivo alternativos. Outros interesses são a melhora da sobrevivência dos microrganismos durante a passagem pelo trato gastrintestinal por meio da microencapsulação e a elaboração de um produto com potencial probiótico que não necessite da cadeia do frio. Dentro deste contexto o presente trabalho objetivou a produção de microrganismo potencialmente probiótico em meio de cultivo vegetal e após microencapsulado, para obtenção de um pó alimentício para ser diretamente utilizado em alimentos. Na primeira etapa deste trabalho foi realizada uma avaliação de variáveis para fixar os parâmetros de processo e o meio de cultivo em biorreator submerso, para produção de biomassa de Lactobacillus plantarum BL011. O meio de cultivo e parâmetros de processo que apresentaram os melhores resultados para a produção de biomassa e ácido láctico foram: 40 g L-1 de açúcares totais (soro ácido de soja); 15 g L-1 de extrato de levedura; velocidade de agitação de 200 rpm; 25 °C e 4,5 vvm. Os resultados obtidos permitiram uma produção de biomassa de 17,87 g L-1 e 37,59 g L-1 de ácido láctico. Em uma segunda etapa deste trabalho o microrganismo foi microencapsulado pela técnica de electrospraying, utilizando como agentes encapsulantes alginato de sódio (ALG) e uma mistura de alginato de sódio e pectina cítrica (ALG-PEC). As células microbianas livres e microencapsuladas foram submetidas ao suco gástrico simulado (SGS) e suco intestinal simulado (SIS). O microrganismo controle (células livres) demonstrou uma diminuição de 6 e 4,2 log UFC mL-1 depois de 120 min de exposição, respectivamente. No entanto, as células microencapsuladas em ALG e em ALG-PEC apresentaram resistência considerável, diminuindo 2,9 log UFC mL-1 para SGS e 2,7 log UFC mL-1 para SIS. Testes de armazenamento sob temperatura de refrigeração por 21 dias apresentaram boa sobrevivência bacteriana de 9,3 log UFC mL-1 (ALG) e 8,6 log UFC mL-1 (ALG-PEC) para células microencapsuladas, enquanto que as células livres apresentaram uma sobrevivência de apenas 1,2 log UFC mL-1 Na terceira etapa foram realizados experimentos para obtenção do pó alimentício com potencial probiótico, onde o microrganismo microencapsulado em ALG foi liofilizado e analisada a viabilidade no período de 6 meses de armazenamento a temperatura ambiente (25 °C), aqual foi mantida acima de 7 log UFC g-1 de pó alimentício, a análise microbiológica (conforme legislação brasileira) realizada antes e após o período de armazenamento não demonstrou contaminações para os patógenos avaliados. Realizou-se uma análise sensorial adicionando o pó alimentício em suco natural de laranja, obtendo aceitação sensorial elevada, maior que 88 %. O suco com adição do pó alimentício foi exposto aos SGS e SIS e apresentou, após 120 min, redução de apenas 2,4 log UFC mL-1 para SGS e 1,3 log UFC mL-1 para SIS. / Probiotic microorganisms are considered living dietary supplements showing benefic effects to hosts by improving the intestinal balance. The high cell density production of Lactobacillus has been the interest of many studies and presents great interest for industry, along with the development of new alternative culture media. Other concerns are the improvement of the survival of microorganisms during passage through the gastrointestinal tract by means of microencapsulation, and the preparation of a product with probiotic potential that would require no cold chain. In this context, this study aimed at producing potentially probiotic bacterium with alternative sources of cultivation substrates and its microencapsulation to obtain a food powder to be used directly in food. In the first step of this study a screnning of variables was carried out to set the process parameters and culture medium in the submerged bioreactor for the production of L. plantarum BL011 The optimized culture medium and processing parameters for biomass and lactic acid formation were: 40 g L-1 total sugar (liquid acid protein residue of soybean); 15 g L-1 yeast extract; stirring speed of 200 rpm; 25 °C, and 4.5 vvm. The results obtained allowed for a production of 17.87 g L-1 of biomass and 37.59 g L-1 of lactic acid. In a second step of this study L. plantarum BL011 was microencapsulated using the electrospraying technique, using as encapsulating agents sodium alginate (ALG) and a mixture of sodium alginate and citrus pectin (ALG-PEC). The free and microencapsulated cells were subjected to the simulated gastric juice (SGJ) and simulated intestinal juice (SIJ). The microorganism control (free cells) showed a decrease of 6 and 4.2 log CFU mL-1 after 120 min of exposure, respectively. However, the microencapsulated cells in ALG and in ALG-PEC showed significant resistance, decreasing by 2.9 log CFU mL-1 in SGJ, and 2.7 log CFU mL-1 in SIJ. Storage tests under refrigeration temperature for 21 days showed good bacterial survival of 9.3 log CFU mL-1 (ALG) and 8.6 log CFU mL-1 (ALG-PEC) for microencapsulated cells, whereas free cells showed a survival of only 1.2 log CFU mL-1 In the third step of the work, it was obtained a food powder with probiotic potential, where the ALG-microencapsulated bacterium was lyophilized and viability was investigated within 6 months of storage at room temperature (25 °C), keeping 7 log CFU g-1 product of its initial value. Microbiological analyses (according to Brazilian legislation) performed before and after the storage period did not show any contaminations by pathogens. The formulated orange juice containing L. plantarum BL011 obtained high sensory acceptance (> 88 %) in the sensory analysis. The juice with the addition of food powder was exposed to SGJ and SIJ and presented, after 120 min, reduction of 2.4 log CFU mL-1 for SGJ and 1.3 log CFU mL-1 for SIJ.

Inositol dehydrogenase (IDH) catalyzes the oxidation of myo-inositol to scyllo-inosose using NAD+ as the coenzyme. IDH-related genes (Lp_iolG1 to Lp_iolG4) from Lactobacillus plantarum WCSF1 and (Lc_iolG1 and Lc_iolG2) from Lactobacillus casei BL23 were cloned into the vector pQE-80L, expressed in E. coli host cells and the proteins were purified to homogeneity. IDH activity of the purified enzymes was explored with myo-inositol and other structurally related compounds. It was found that IDH-related enzymes from L. plantarum WCSF1 did not exhibit any activity with tested substrates but, LcIDH1 and LcIDH2 from L. casei BL23 showed activity with myo-inositol and other related compounds. pH-rate profile studies have demonstrated the optimum pH for the reactions catalyzed by the active enzymes. Steady-state kinetics of the active enzymes was performed as with IDH from Bacillus subtilis (BsIDH), revealing that LcIDH1 is a myo-inositol dehydrogenase and LcIDH2 is a scyllo-inositol dehydrogenase. Both LcIDH1 and LcIDH2 are observed to be NAD+-dependent. Kinetic isotopic effect experiments for LcIDH1 have demonstrated that the chemical step in the reaction is partly rate-limiting. Substrate spectrum of LcIDH1 and LcIDH2 was explored and compared to BsIDH. Finally, a multiple sequence alignment of IDH-related enzymes was performed and the proposed consensus sequence motifs were considered to understand the activity differences between these enzymes.

Os microrganismos probióticos são considerados suplementos alimentares vivos, apresentando benefícios ao hospedeiro e melhorando o balanço intestinal. A produção de Lactobacillus com alta densidade celular vem sendo estudada e possui grande interesse por parte da indústria, bem como o estudo de novos meios de cultivo alternativos. Outros interesses são a melhora da sobrevivência dos microrganismos durante a passagem pelo trato gastrintestinal por meio da microencapsulação e a elaboração de um produto com potencial probiótico que não necessite da cadeia do frio. Dentro deste contexto o presente trabalho objetivou a produção de microrganismo potencialmente probiótico em meio de cultivo vegetal e após microencapsulado, para obtenção de um pó alimentício para ser diretamente utilizado em alimentos. Na primeira etapa deste trabalho foi realizada uma avaliação de variáveis para fixar os parâmetros de processo e o meio de cultivo em biorreator submerso, para produção de biomassa de Lactobacillus plantarum BL011. O meio de cultivo e parâmetros de processo que apresentaram os melhores resultados para a produção de biomassa e ácido láctico foram: 40 g L-1 de açúcares totais (soro ácido de soja); 15 g L-1 de extrato de levedura; velocidade de agitação de 200 rpm; 25 °C e 4,5 vvm. Os resultados obtidos permitiram uma produção de biomassa de 17,87 g L-1 e 37,59 g L-1 de ácido láctico. Em uma segunda etapa deste trabalho o microrganismo foi microencapsulado pela técnica de electrospraying, utilizando como agentes encapsulantes alginato de sódio (ALG) e uma mistura de alginato de sódio e pectina cítrica (ALG-PEC). As células microbianas livres e microencapsuladas foram submetidas ao suco gástrico simulado (SGS) e suco intestinal simulado (SIS). O microrganismo controle (células livres) demonstrou uma diminuição de 6 e 4,2 log UFC mL-1 depois de 120 min de exposição, respectivamente. No entanto, as células microencapsuladas em ALG e em ALG-PEC apresentaram resistência considerável, diminuindo 2,9 log UFC mL-1 para SGS e 2,7 log UFC mL-1 para SIS. Testes de armazenamento sob temperatura de refrigeração por 21 dias apresentaram boa sobrevivência bacteriana de 9,3 log UFC mL-1 (ALG) e 8,6 log UFC mL-1 (ALG-PEC) para células microencapsuladas, enquanto que as células livres apresentaram uma sobrevivência de apenas 1,2 log UFC mL-1 Na terceira etapa foram realizados experimentos para obtenção do pó alimentício com potencial probiótico, onde o microrganismo microencapsulado em ALG foi liofilizado e analisada a viabilidade no período de 6 meses de armazenamento a temperatura ambiente (25 °C), aqual foi mantida acima de 7 log UFC g-1 de pó alimentício, a análise microbiológica (conforme legislação brasileira) realizada antes e após o período de armazenamento não demonstrou contaminações para os patógenos avaliados. Realizou-se uma análise sensorial adicionando o pó alimentício em suco natural de laranja, obtendo aceitação sensorial elevada, maior que 88 %. O suco com adição do pó alimentício foi exposto aos SGS e SIS e apresentou, após 120 min, redução de apenas 2,4 log UFC mL-1 para SGS e 1,3 log UFC mL-1 para SIS. / Probiotic microorganisms are considered living dietary supplements showing benefic effects to hosts by improving the intestinal balance. The high cell density production of Lactobacillus has been the interest of many studies and presents great interest for industry, along with the development of new alternative culture media. Other concerns are the improvement of the survival of microorganisms during passage through the gastrointestinal tract by means of microencapsulation, and the preparation of a product with probiotic potential that would require no cold chain. In this context, this study aimed at producing potentially probiotic bacterium with alternative sources of cultivation substrates and its microencapsulation to obtain a food powder to be used directly in food. In the first step of this study a screnning of variables was carried out to set the process parameters and culture medium in the submerged bioreactor for the production of L. plantarum BL011 The optimized culture medium and processing parameters for biomass and lactic acid formation were: 40 g L-1 total sugar (liquid acid protein residue of soybean); 15 g L-1 yeast extract; stirring speed of 200 rpm; 25 °C, and 4.5 vvm. The results obtained allowed for a production of 17.87 g L-1 of biomass and 37.59 g L-1 of lactic acid. In a second step of this study L. plantarum BL011 was microencapsulated using the electrospraying technique, using as encapsulating agents sodium alginate (ALG) and a mixture of sodium alginate and citrus pectin (ALG-PEC). The free and microencapsulated cells were subjected to the simulated gastric juice (SGJ) and simulated intestinal juice (SIJ). The microorganism control (free cells) showed a decrease of 6 and 4.2 log CFU mL-1 after 120 min of exposure, respectively. However, the microencapsulated cells in ALG and in ALG-PEC showed significant resistance, decreasing by 2.9 log CFU mL-1 in SGJ, and 2.7 log CFU mL-1 in SIJ. Storage tests under refrigeration temperature for 21 days showed good bacterial survival of 9.3 log CFU mL-1 (ALG) and 8.6 log CFU mL-1 (ALG-PEC) for microencapsulated cells, whereas free cells showed a survival of only 1.2 log CFU mL-1 In the third step of the work, it was obtained a food powder with probiotic potential, where the ALG-microencapsulated bacterium was lyophilized and viability was investigated within 6 months of storage at room temperature (25 °C), keeping 7 log CFU g-1 product of its initial value. Microbiological analyses (according to Brazilian legislation) performed before and after the storage period did not show any contaminations by pathogens. The formulated orange juice containing L. plantarum BL011 obtained high sensory acceptance (> 88 %) in the sensory analysis. The juice with the addition of food powder was exposed to SGJ and SIJ and presented, after 120 min, reduction of 2.4 log CFU mL-1 for SGJ and 1.3 log CFU mL-1 for SIJ.

Os microrganismos probióticos são considerados suplementos alimentares vivos, apresentando benefícios ao hospedeiro e melhorando o balanço intestinal. A produção de Lactobacillus com alta densidade celular vem sendo estudada e possui grande interesse por parte da indústria, bem como o estudo de novos meios de cultivo alternativos. Outros interesses são a melhora da sobrevivência dos microrganismos durante a passagem pelo trato gastrintestinal por meio da microencapsulação e a elaboração de um produto com potencial probiótico que não necessite da cadeia do frio. Dentro deste contexto o presente trabalho objetivou a produção de microrganismo potencialmente probiótico em meio de cultivo vegetal e após microencapsulado, para obtenção de um pó alimentício para ser diretamente utilizado em alimentos. Na primeira etapa deste trabalho foi realizada uma avaliação de variáveis para fixar os parâmetros de processo e o meio de cultivo em biorreator submerso, para produção de biomassa de Lactobacillus plantarum BL011. O meio de cultivo e parâmetros de processo que apresentaram os melhores resultados para a produção de biomassa e ácido láctico foram: 40 g L-1 de açúcares totais (soro ácido de soja); 15 g L-1 de extrato de levedura; velocidade de agitação de 200 rpm; 25 °C e 4,5 vvm. Os resultados obtidos permitiram uma produção de biomassa de 17,87 g L-1 e 37,59 g L-1 de ácido láctico. Em uma segunda etapa deste trabalho o microrganismo foi microencapsulado pela técnica de electrospraying, utilizando como agentes encapsulantes alginato de sódio (ALG) e uma mistura de alginato de sódio e pectina cítrica (ALG-PEC). As células microbianas livres e microencapsuladas foram submetidas ao suco gástrico simulado (SGS) e suco intestinal simulado (SIS). O microrganismo controle (células livres) demonstrou uma diminuição de 6 e 4,2 log UFC mL-1 depois de 120 min de exposição, respectivamente. No entanto, as células microencapsuladas em ALG e em ALG-PEC apresentaram resistência considerável, diminuindo 2,9 log UFC mL-1 para SGS e 2,7 log UFC mL-1 para SIS. Testes de armazenamento sob temperatura de refrigeração por 21 dias apresentaram boa sobrevivência bacteriana de 9,3 log UFC mL-1 (ALG) e 8,6 log UFC mL-1 (ALG-PEC) para células microencapsuladas, enquanto que as células livres apresentaram uma sobrevivência de apenas 1,2 log UFC mL-1 Na terceira etapa foram realizados experimentos para obtenção do pó alimentício com potencial probiótico, onde o microrganismo microencapsulado em ALG foi liofilizado e analisada a viabilidade no período de 6 meses de armazenamento a temperatura ambiente (25 °C), aqual foi mantida acima de 7 log UFC g-1 de pó alimentício, a análise microbiológica (conforme legislação brasileira) realizada antes e após o período de armazenamento não demonstrou contaminações para os patógenos avaliados. Realizou-se uma análise sensorial adicionando o pó alimentício em suco natural de laranja, obtendo aceitação sensorial elevada, maior que 88 %. O suco com adição do pó alimentício foi exposto aos SGS e SIS e apresentou, após 120 min, redução de apenas 2,4 log UFC mL-1 para SGS e 1,3 log UFC mL-1 para SIS. / Probiotic microorganisms are considered living dietary supplements showing benefic effects to hosts by improving the intestinal balance. The high cell density production of Lactobacillus has been the interest of many studies and presents great interest for industry, along with the development of new alternative culture media. Other concerns are the improvement of the survival of microorganisms during passage through the gastrointestinal tract by means of microencapsulation, and the preparation of a product with probiotic potential that would require no cold chain. In this context, this study aimed at producing potentially probiotic bacterium with alternative sources of cultivation substrates and its microencapsulation to obtain a food powder to be used directly in food. In the first step of this study a screnning of variables was carried out to set the process parameters and culture medium in the submerged bioreactor for the production of L. plantarum BL011 The optimized culture medium and processing parameters for biomass and lactic acid formation were: 40 g L-1 total sugar (liquid acid protein residue of soybean); 15 g L-1 yeast extract; stirring speed of 200 rpm; 25 °C, and 4.5 vvm. The results obtained allowed for a production of 17.87 g L-1 of biomass and 37.59 g L-1 of lactic acid. In a second step of this study L. plantarum BL011 was microencapsulated using the electrospraying technique, using as encapsulating agents sodium alginate (ALG) and a mixture of sodium alginate and citrus pectin (ALG-PEC). The free and microencapsulated cells were subjected to the simulated gastric juice (SGJ) and simulated intestinal juice (SIJ). The microorganism control (free cells) showed a decrease of 6 and 4.2 log CFU mL-1 after 120 min of exposure, respectively. However, the microencapsulated cells in ALG and in ALG-PEC showed significant resistance, decreasing by 2.9 log CFU mL-1 in SGJ, and 2.7 log CFU mL-1 in SIJ. Storage tests under refrigeration temperature for 21 days showed good bacterial survival of 9.3 log CFU mL-1 (ALG) and 8.6 log CFU mL-1 (ALG-PEC) for microencapsulated cells, whereas free cells showed a survival of only 1.2 log CFU mL-1 In the third step of the work, it was obtained a food powder with probiotic potential, where the ALG-microencapsulated bacterium was lyophilized and viability was investigated within 6 months of storage at room temperature (25 °C), keeping 7 log CFU g-1 product of its initial value. Microbiological analyses (according to Brazilian legislation) performed before and after the storage period did not show any contaminations by pathogens. The formulated orange juice containing L. plantarum BL011 obtained high sensory acceptance (> 88 %) in the sensory analysis. The juice with the addition of food powder was exposed to SGJ and SIJ and presented, after 120 min, reduction of 2.4 log CFU mL-1 for SGJ and 1.3 log CFU mL-1 for SIJ.

Bakgrund: IBS (Irritable bowel syndrome) är en funktionell mag-tarmsjukdom med en oklar orsak och patofysiologi. IBS förekommer mest hos kvinnor och karakteriseras av buksmärta, uppblåsthet, diarré och/eller förstoppning samt ökad gasbildning. I nuläget finns inga läkemedel som botar sjukdomstillståndet, och den senaste tiden har intresset för probiotika som behandling av IBS ökat. Probiotika innehåller levande mikroorganismer som anses ha en gynnsam effekt på tarmflorans sammansättning, samt kan tros ha en symtomatisk effekt vid IBS. Syfte: Syftet med detta litteraturarbete är att ta reda på om kosttillskott som innehåller bakteriearten Lactobacillus plantarum har en positiv effekt för att lindra symtomen hos patienter som lider av en diarrépredominant IBS. Metod: Sex randomiserade, dubbelblinda och placebo-kontrollerade studier granskades. Studierna utvärderade effekten av den enskilda bakteriearten L. plantarum eller en kombination av probiotika som innehöll L. plantarum för symtomlindring hos IBS-patienter. Artikelsökning utfördes i databasen PubMed via Linnéuniversitetets bibliotek. Resultat: Tre av de fyra studierna som undersökte L. plantarum i kombination med andra bakteriestammar påvisade en statistiskt signifikant förbättring av symtomen buksmärta hos IBSpatienter. En av de två studierna som undersökte enbart L. plantarum visade en signifikant förbättring av symtomen buksmärta. Två av sex studier visade ingen signifikant förbättring av symtomlindring mellan probiotika- och placebo gruppen. Slutsats: Utifrån sammanställningen påvisades att effekten uppnåddes framförallt i gruppen med måttliga IBS besvär. Dock gav inte behandling med L. plantarum alltid en statistisk signifikant förbättring av symtomlindring hos diarré predominanta IBS-patienter. Vidare studier behövs på subtypen diarré predominant IBS för att stärka och fastställa L. plantarums effekt.

Počet obyvatel trpících různými infekčními, zánětlivými a alergickými nemocemi stejně jako výskyt laktózové nesnášenlivosti a vysoké hodnoty krevního cholesterolu, má narůstající tendenci. Některé z těchto zdravotních problémů jsou způsobeny nevyváženou střevní mikroflorou. Probiotika jsou pak chápána (nejen) jako potravní komponenty, které přispívají k ustanovení mikrobiální rovnováhy (Parker, 1974) mezi zdraví prospěšnými a škodlivými bakteriemi. Z tohoto důvodu, terapie založená na podávání probiotik pacientům přitáhla zájem ze strany vědců. Vhodný probiotický kmen se pak volí v závislosti na požadovaném zdravotním účinku (příp. zdravotním problému, který má být probiotickou terapií léčen). Lactobacillus plantarum 299v již prokázal své blahodárné účinky na lidech a zároveň byla i potvrzena jeho zdravotní bezpečnost, díky čemuž může tato bakterie být kategorizována jako probiotický kmen (Probi AB, Sweden). I díky tomu je Lactobacillus plantarum 299v ve značné oblibě přidáván do mnoha fukčních potravin a prodáván na trhu pod různými jmény, probiotický nápoj ProViva je jedním takovým příkladem. Cílem této práce bylo studovat fermentační proces na žitném, ječmenném a sojovém substrátu pomocí kmene Lactobacillus plantarum 299v, přičemž zvýšená pozornost byla věnována právě soji a ječmeni jako potenciálně novým substrátům pro výše uvedenou bakterii. Hlavními záměry bylo zkoumání růstu a metabolické aktivity bakterie Lactobacillus plantarum 299v v asociaci s různými cereálními substráty, a později bylo studováno totéž také ve směsi fermentované cereální komponenty s běžně dostupným ovocným džusem. K tomu, aby se dosáhlo optimálních podmínek fermentace, je třeba vzít v úvahu několik aspektů. Hlavní role při konceptování nového fermentovaného produktu patří především zpracování a taktéž kompozici surového materiálu, růstové kapacitě a produktivitě bakteriální kultury a stabilitě finálního produktu během skladování (De Vuyst, 2000). Tyto parametry jsou důležité hlavně ze strany výrobců. Krom toho jsou tu ale i zákazníci, pro něž je přijatelnost produktu založena z velké části na organoleptických vlastnostech finálního probiotického produktu, tj. aromatu a chuti. Přítomnost a dostupnost různých jednotlivých nutrientů, která byla obsažena ve fermentačním médiu výsledkem rozdílných použitých cereálních substrátů, pravděpodobně vyústila v odlišnosti metabolických drah, což pak později mohlo způsobit rozdíly v organoleptických vlastnostech finálního produktu.