In this project the factors influencing the stability and antimicrobial activity of allyl isothiocyanate (AITC) against Campylobacter jejuni, Salmonella or Listeria monocytogenes as well as factors that enhance sinigrin (glucosinolate in Oriental mustard) hydrolysis by these pathogens were investigated. The minimum inhibitory concentration (MIC) of AITC against 5 strains of each of Salmonella or L. monocytogenes, ranged from 60-100 ppm at 37 ºC. This was reduced to 10-40 ppm at 21 ºC and a further reduction to 5-10 ppm against strains of L. monocytogenes was observed at 4 ºC. This was attributed to greater stability of AITC as temperature was decreased. C. jejuni strains were more susceptible to AITC with MICs of 0.63-1.25 ppm and 2.5-5 ppm at 37 and 42 ºC, respectively. AITC was more inhibitory at ≤ 21 ºC against Salmonella with acidic pH or against L. monocytogenes with neutral pH. C. jejuni, Salmonella and L. monocytogenes strains and mixtures had the ability to degrade sinigrin to form inhibitory concentrations of AITC, and sinigrin hydrolysis was significantly enhanced by higher incubation temperature (21 ºC > 10 ºC > 4 ºC), the presence of 10 mM ferric or ferrous irons, and the presence of < 0.25% glucose. This project also investigated the antimicrobial activity of AITC or Oriental mustard extract alone or combined with ethylenediamine tetraacetic acid (EDTA), malic acid and acetic acid in edible antimicrobial coatings against C. jejuni and Salmonella on fresh, refrigerated, vacuum-packed chicken breasts or L. monocytogenes on refrigerated, cured roast chicken. Malic acid improved the antimicrobial activity of Oriental mustard extract against L. monocytogenes, while EDTA improved its activity against Salmonella. Incorporation of 25 to 50 µl/g AITC or 100 to 250 mg/g Oriental mustard extract in 0.5%κ-carrageenan/2%chitosan coatings, prepared using 1.5% malic or acetic acid, reduced L. monocytogenes on cooked, cured, vacuum-packed chicken slices 4.2 to > 7.0 log10 CFU/g, compared to uncoated chicken by 70 d at 4 ºC. In addition, 0.2%κ-carrageenan/2%chitosan coatings (prepared using a 1% acetic acid solution) containing 250 mg/g mustard extract or 50 µl/g AITC reduced Salmonella numbers on vacuum-packed chicken breasts 3.0 log10 CFU/g by 21 d at 4 ºC. Further, 0.2%κ-carrageenan/2%chitosan coatings containing 50 or 100 µl/g AITC reduced numbers of C. jejuni on fresh, vacuum-packed chicken breasts > 5.0 log10 CFU/g (C. jejuni cells were not detected) after 5 d storage at 4 ºC, while coatings containing 200 to 300 mg/g Oriental mustard extract or 25 µl/g AITC reduced C. jejuni numbers by 3.6 to 4.6 log10 CFU/g. Numbers of lactic acid and aerobic bacteria on poultry meat products were significantly reduced by the coatings. It is clear that κ-carrageenan/chitosan coatings containing either AITC, mustard extract alone or combined with EDTA, malic or acetic acid significantly reduced C. jejuni and Salmonella on fresh, refrigerated, vacuum-packed chicken breasts and L. monocytogenes on refrigerated, cured roast chicken, and consequently enhanced their safety.

Darbo tikslas: ištirti ksilanazių, beta gliukanazių, celiulazių ir amonio propionato bei pieno rūgšties įtaką viščiukų broilerių virškinimo procesams. Uždaviniai: 1. ištirti ksilanazių, beta gliukanazių, celiulazių ir amonio propionato bei pieno rūgšties įtaką viščiukų broilerių produktyvumui. 2. ištirti ksilanazių, beta gliukanazių, celiulazių ir amonio propionato bei pieno rūgšties įtaką viščiukų broilerių virškinimo procesams. Išvados: 1. Fermentinio preparato (pagrindiniai fermentiniai aktyvumai - ksilanazių, beta gliukanazių, celiulazių) tiek vieno, tiek kartu su organinėmis rūgštimis (amonio propionato pieno rūgštis) įtakojo viščiukų broilerių kūno masės didėjimą 2 proc., lesalų sąnaudų 1 kg priesvorio gauti sumažėjimą 6 proc., lyginant su kontroline grupe (p > 0,05). Lesalų priedai neturėjo įtakos viščiukų broilerių gaištamumui. 2. Fermentinio preparato ir organinių rūgščių poveikyje pH turėjo didėjimo tendencija dvylikapirštės ir plonosios žarnų, turinyje tuo tarpu aklosios žarnos turinyje šis rodiklis buvo žemesnis, lyginant su kontroline grupe (p > 0,05). 3. Lesalų priedų panaudojimas, įtakojo didesni SM kiekį viščiukų broilerių virškinamojo trakto turinyje, lyginant su kontroline grupe. 4. Fermentinio preparato poveikyje (II tiriamoji grupė) acto, propiono ir sviesto rūgščių kiekis aklosios žarnos turinyje padidėjo nežymiai, atitinkamai 0,1, 0,12 ir 0,08 proc., o III tiriamojoje grupėje (fermentinis preparatas + organinės rūgštys) acto ir sviesto rūgščių kiekis... [toliau žr. visą tekstą] / The aim of the work: to investigate the influence of xylanase, beta glucanase, cellulase, ammonium propionate and lactic acid on digestion process of broiler chickens. The tasks of labor: 1. to investigate the influence of of xylanase, beta glucanase, cellulase, ammonium propionate and lactic acid on productivity of broiler chickens; 2. to investigate the influence of xylanase, beta glucanase, cellulase, ammonium propionate and lactic acid on digestion process of broiler chickens. Conclusious: 1. Enzymes (xylanase, beta glucanase, cellulase) used alone or with organic acids (ammonium propionate, lactic acid) influenced the weight increase of broiler chickens by 2%, feed consumption per 1kg decrease in weight gain was 6%, compared with the control group (p > 0.05). Feed additives had no effect on mortality of broiler chickens. 2. pH tends to increase in the duodenum and small intestine, while in caecum this rate was lower compared to the control group (p > 0.05). 3. The use of feed additives influenced the higher DM content in broiler chickens digestive tract content, compared with the control group. 4. In the second experimental group acetic, propionic and butyric acids increased slightly, by 0.1, 0.12 and 0.08%, compared to the control group (p > 0.05). In the third experimental group acetic and propionic acids increased by 0.93 and 0.33%, while butyric acids decreased by 0.65% compared with the control group (p > 0.05). 5. In both - the second and the third – investigated... [to full text]

Nutriomics is the study of the whole range of nutritional components (nutriome) in foods. In order to further understand the molecular basis for the positive health benefits of fruits identified from epidemiology, the mass balance through the human digestion and absorption should be studied. The components of the nutriome studied in this research were sugars, carotenoids, phenolics and organic acids, all important for defining dietary – human health relationships and linking to evidence obtained from epidemiological studies. An attempt to approach a realistic human mimetic digestion and absorption model has been carried out in this study using a static in-vitro model of the human digestive system. Two major novelities in this model compared to other in-vitro models are (i) the use of particles of solid fruit products that mimic the products of human chewing and (ii) a cell-based (Caco-2) in-vitro intestinal absorption model. Hence, imitative bioavailability, i.e. releasing nutrients and potential levels of target compounds reaching the portal circulatory system could be assessed. The fruits studied were tomato, mango, papaya; each as fresh, dried and juiced forms. In-vivo chewing suggested 0.5 cm size modes for dried products and 1.5 cm for fresh products. The agglomerates that were obtained from the chewing of dried products disaggregated during in-vitro digestions in the presence of acids (gastric simulation) or sodium bicarbonate at pH 6 (small intestinal simulation). The extent of this disaggregation followed the order: tomato > mango > papaya. Although all fresh samples contained separated cells, their responses to a 5 mm texture analysis probe (mimicking teeth cusps) varied depending on fruit products. All matrices were hardened by drying, becoming more brittle and breaking easier to produce smaller size modes. Variation between individual participants in the size of their chewed particles was lower for fresh products and high for dried products. The in-vitro digestion and absorption model developed had simulated particle sizes of approximately 0.5 cm3 for dried products or 1.5 cm3 (thickness varied with the products) for fresh products in a 9:1 ratio mix with blended samples, and were digested in-vitro using the following steps: 1. ‘Chewing’: pH 6.9; 37 C, 10 min, in a shaking-water bath (55 rpm) with human alpha-amylase (100 U/L). 2. ‘Gastric’ digestion: pH 2; 37 C, 60 min, in a shaking-water (55 rpm) with porcine pepsin (40 µg/L). 3. ‘Intestinal’ digestion: pH 6; 37 C, 60 min, in a shaking-water bath (55 rpm) with porcine pancreatin and bile extract (1.4 µg/L and 8.6 µg/L, respectively). 4. Caco-2 cell monolayer in-vitro passages: aged 22 days post confluent monolayers in a 24 transwell-insert well plate seeded at 105 cells, pH 7.4 with renewal of apical and basolateral solutions every 30 min for bioavailability estimations. In this study, two models of basolateral – apical solution renewals were carried out: both apical and basolateral were renewed (model A) and basolateral only was renewed (model B). To study metabolites produced by Caco-2 cells, the bioassays were carried out for 22 h without renewals of apical and basolateral solutions (model C). An overview of nutriomics analysis of in-vitro digestions of mango, papaya and tomato based on principal component analysis (PCA) suggested: (1) fruit types led to variable nutriome releases: in-vitro digestions affected tomato >mango >papaya; (2) processing varied nutriome releases from fruit products with juicing tended to release more nutriome components, whereas drying and unprocessed (fresh) did not show noticeably different patterns; (3) gastric and simultaneous gastric-intestinal digestions were similar in nutriome releases whereas contributions of intestinal digestion alone were negligible for water soluble nutriome components; and overall (4) during in-vitro digestions there were no interactions among releasing nutriome from the fruit products studied (independent nutriome releasing processes). Phenolic components showed molecular changes during in-vitro digestion and processing, due to, heating effects, pH or enzymic degradations. Caco-2 bioassays using model compounds showed a range of monolayer responses as follows: (1) mannitol, lycopene and catechin were strictly retained in the apical solution; (2) sugars, caffeine and atenolol were translocated in the apical-to-basolateral direction as intact molecules; (3) Beta-carotene partially disappeared from the apical solution without basolateral release. Models A – C consistently confirmed these responses. Low recoveries provided evidence for cellular metabolisms of (particularly) phenolic and carotenoid molecules by the Caco-2 cell monolayers.

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

O cenário atual da produção avícola brasileira é definido pela alta produtividade motivada pelas exportações para mercados com elevados níveis de exigência sanitária. O trabalho objetivou avaliar a eficácia de compostos clorados (dióxido de cloro, dicloro e tricloro) e ácidos orgânicos (ácidos cítrico, lático e peracético) na redução da contaminação de carne de frango por Salmonella spp., mesófilos e enterobactérias. Foram isoladas 102 cepas de Salmonella spp. de carcaças de frango no período de junho a setembro de 2014. As cepas foram identificadas por PCR. Determinou-se a concentração inibitória mínima (CIM) dos compostos para as cepas padrões de S. Typhimurium, S. Enteritidis e S. Heidelberg. A CIM dos ácidos lático e peracético (20 e 10 g/L) foi aplicada em cepas de Salmonella spp. isoladas do frigorífico. A CIM dos compostos ácido lático e dicloro foi aplicada em água de chiller contaminada com Salmonella (109 UFC/mL) e foi determinada a contagem de Salmonella presente na água. Coxas e sobrecoxas de frango foram contaminadas com S. Heidelberg (109 UFC/mL) e foram aplicados os compostos dicloro (60 mg/L), ácido lático (20 g/L) e hipoclorito de sódio (5,0 e 0,5 mg/L). Na identificação por PCR, 93,1% das cepas foram identificadas como Salmonella spp. Para o dicloro a CIM foi de 60 mg/L por 15 minutos para S. Heidelberg e 60 mg/L por 20 minutos para S. Enteritidis. O ácido lático apresentou CIM de 5 g/L por 10 minutos para S. Enteritidis, 10 g/L por 15 minutos para S. Typhimurium e 20 g/L por 20 minutos para S. Heidelberg. Para o ácido peracético, as CIMs foram de 10 g/L por 10 minutos para S. Typhimurium e S. Heidelberg e 10 g/L por 20 minutos para S. Enteritidis. Para o ácido cítrico, as CIMs foram de 10 g/L por 10 minutos para S. Typhimurium e S. Enteritidis e 25 g/L por 20 minutos para S. Heidelberg. Nas cepas de Salmonella isoladas, o ácido lático inibiu 97,89% das cepas e o peracético inibiu 100% das cepas. Na água de chiller contaminada os compostos reduziram o crescimento das cepas padrões. Quando aplicados em carne de frango contaminada, houve redução de Salmonella spp. de 1,06 log10 UFC/g em relação ao controle positivo com o hipoclorito de sódio a 5,0 mg/L, 0,97 log10 UFC/g com o dicloro e 0,56 log10 UFC/g com o hipoclorito de sódio a 0,5 mg/L. Para mesófilos a redução observada foi de 0,90 log10 UFC/g em relação ao controle positivo com o hipoclorito de sódio a 5,0 mg/L, 0,90 log10 UFC/g com o dicloro e não havendo redução com o hipoclorito de sódio a 0,5 mg/L. Para enterobactérias a redução foi de 1,0 log10 UFC/g em relação ao controle positivo com o hipoclorito de sódio a 5,0 mg/L, 0,79 log10 UFC/g com o dicloro e 0,22 log10 UFC/g com o hipoclorito de sódio a 0,5 mg/L. O ácido lático inibiu o crescimento bacteriano dos micro-organismos testados. Os dados obtidos reforçam a necessidade de discussões para regulamentar o uso de coadjuvantes de tecnologia no abate de aves. / The current scenario of the Brazilian poultry production is defined by high productivity motivated by exports to markets with elevated levels of sanitary requirement. The work aimed to evaluate the efficacy of chlorinated compounds (chlorine dioxide, dichloro and trichloro) and organic acids (citric, lactic and peracetic acids) in reducing the contamination of poultry by Salmonella spp., mesophiles and enterobacteriaceae. Were isolated 102 strains Salmonella spp. poultry carcass from June to September 2014. Strains were identified by PCR. Was determined the minimum inhibitory concentration (MIC) of antimicrobial compounds for the standard strains of S. Typhimurium, S. Enteritidis and S. Heidelberg. MIC of lactic acid and peracetic acid (20 to 10 g/L) was applied in strains of Salmonella spp. isolated from the slaughter. The MIC of the compounds lactic acid and sodium dichloro was applied in contaminated chiller water with Salmonella (109 CFU/mL) and this was determined Salmonella count in water. Thighs and drumsticks poultry were contaminated with S. Heidelberg (109 UFC/mL) and were applied dichloro (60 mg/L), lactic acid (20 g/L) and sodium hypochlorite (5,0 and 0,5 mg/L) compounds. In the identification by PCR, 93,1% of the strains were identified as Salmonella. For sodium dichloro the MIC was 60 mg/L for 15 minutes to S. Heidelberg and 60 mg/L for 20 minutes for S. Enteritidis. Lactic acid presented MIC of the 5 g/L for 10 minutes to S. Enteritidis 10 g/L for 15 minutes to S. Typhimurium and 20 g/L for 20 minutes to S. Heidelberg. For peracetic acid, MICs were 10 g/L for 10 minutes to S. Typhimurium and S. Heidelberg and 10 g/L for 20 minutes to S. Enteritidis. To citric acid, MICs were 10 g/L for 10 minutes to S. Typhimurium and S. Enteritidis and 25 g/L for 20 minutes to S. Heidelberg. In the isolated Salmonella strains, lactic acid inhibited 97,89% of the strains and peracetic inhibited 100% of the strains. In contaminated chiller water, the compounds reduced the growth of standards strains. When applied to contaminated poultry meat, there was a reduction of Salmonella spp. 1,06 log10 CFU/g relative to the positive control with the use of sodium hypochlorite at 5,0 mg/L, 0,97 log10 CFU/g with dichloro and 0,56 log10 CFU/g with sodium hypochlorite 0,5 mg/L. For mesophiles reduction observed was 0,90 log10 CFU/g relative to the positive control with the use of sodium hypochlorite at 5,0 mg/L, 0,83 log10 CFU/g with dichloro and there isn´t reduction with hypochlorite with sodium 0,5 mg/L. For enterobacteriaceae reduction was 1,0 log10 CFU/g relative to the positive control with the use of sodium hypochlorite at 5,0 mg/L, 0,79 log10 CFU/g with dichloro and 0,22 log10 CFU/g with sodium hypochlorite at 0,5 mg/L. Lactic acid inhibit growth of the microorganisms tested. The data supports the discussions to regulate the use of the technology coadjuvants in the slaughter of poultry.

The sausage is a product of high consumption, but due to its manufacturing process technology, it becomes susceptible to microbiological contamination. To ensure the life of the sausage and their microbiological safety, means of minimizing contamination levels, limiting or preventing microbial growth. Therefore, the objective of this study was to add antimicrobials in the formulation and post-heat treatment, and evaluate their effects on growth of mesophilic aerobic bacteria, lactic acid bacteria and Listeria monocytogenes in sausages vacuum packed, stored at 5 º C during storage of 35 days. We evaluated four treatments: (T1-2.5% solution of sodium lactate in the formulation and immersion in 200 mg / l of nisin solution, T2 - 2.5% solution of sodium lactate in the formulation and immersion 200 mg / l of nisin solution followed by 2.5% solution of lactic acid, T3 - 2.5% solution of potassium lactate and sodium diacetate in formulation and immersion in 200 mg / l of nisin solution; T4-2.5% solution of potassium lactate and sodium diacetate in formulation and immersion in 200 mg / l of nisin solution followed by 2.5% lactic acid solution) and a control (no antimicrobial was added in formulation and post-thermal processing). There were microbiological (lactic acid bacteria, aerobic mesophilic, and Listeria monocytogenes) and physico-chemical (pH). At the end of 35 days storage there was a synergy between antimicrobials used in the formulation and post-heat treatment, reducing the total count of mesophilic and lactic acid bacteria, as compared to control, and the (T4), who used the formulating a mixture of potassium lactate and sodium diacetate, with the subsequent nisin followed by immersion in lactic acid more effective. The treatments that were used nisin (T1 e T3), after the heat treatment, were not effective in controlling aerobic mesophilic and lactic acid bacteria. Listeria monocytogenes was identified in all control samples during the 35 days of storage. Thus, the synergistic action of antibiotics added to the formulation, and post-thermal processing are obstacles that had a potential to control the growth of mesophilic aerobic bacteria and lactic acid bacteria and especially able to inhibit the growth of Listeria monocytogenes in vacuum-packed sausages and stored at 5 ° C for 35 days of storage. / A salsicha é um produto de elevado consumo, porém devido ao seu processo tecnológico de fabricação, torna-se susceptível a contaminação microbiológica. Garantir a vida útil da salsicha e a sua segurança microbiológica, implica em minimizar níveis de contaminação, limitando ou impedindo o crescimento microbiano. Portanto, o objetivo deste trabalho foi adicionar antimicrobianos na formulação e no pós-tratamento térmico, e avaliar os efeitos no desenvolvimento das bactérias aeróbias mesófilas, láticas e da Listeria monocytogenes em salsichas embaladas a vácuo, armazenadas a temperatura de 5ºC durante o período de armazenamento de 35 dias. Avaliaram-se quatro tratamentos: (T1- 2,5% de solução de lactato de sódio na formulação e imersão em 200 mg/l de solução de nisina;T2 - 2,5% de solução de lactato de sódio na formulação e imersão em 200 mg/l de solução de nisina seguida de 2,5% de solução de ácido lático;T3 - 2,5% de solução de lactato de potássio e diacetato de sódio na formulação e imersão em 200 mg/l de solução de nisina;T4- 2,5% de solução de lactato de potássio e diacetato de sódio na formulação e imersão em 200 mg/l de solução de nisina seguida de 2,5% de solução de ácido lático) e um controle (não foi adicionado antimicrobianos na formulação e no pós-processamento térmico).Realizaram-se análises microbiológicas (bactérias láticas, aeróbias mesófilas e Listeria monocytogenes) e físico-química (pH). Ao final de 35 dias de armazenamento verificou-se uma sinergia entre os antimicrobianos utilizados na formulação e no pós-tratamento térmico, reduzindo a contagem total de microrganismos mesófilos e bactérias láticas, em relação ao controle, sendo o (T4), que utilizou na formulação a mistura de lactato de potássio e diacetato de sódio, com a posterior imersão em nisina seguida de ácido lático o mais eficaz. Os tratamentos em que foram utilizados a nisina (T1 e T3), no pós-tratamento térmico, não foram eficazes no controle de bactérias aeróbias mesófilas e láticas. A Listeria monocytogenes, foi identificada em todas as amostras controle, durante os 35 dias de armazenamento. Porém, os antimicrobianos adicionados na formulação e no pós-tratamento térmico foram eficazes para prevenir o crescimento do patógeno, com exceção do T1. Desta forma a ação sinergistica de antimicrobianos adicionados na formulação, e no pós-processamento térmico são obstáculos que apresentaram um potencial no controle do crescimento de bactérias aeróbias mesófilas e bactérias láticas e principalmente capazes de inibir o crescimento de Listeria monocytogenes em salsichas embaladas a vácuo e armazenadas a 5ºC por 35 dias de armazenamento.

Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-10-19Bitstream added on 2014-06-13T19:03:38Z : No. of bitstreams: 1 barroso_cb_dr_jabo.pdf: 424873 bytes, checksum: c11fcf246d6ada6dcb329194e9814468 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Devido a baixa disponibilidade de P no solo e a alta capacidade do fungo Aspergillus niger F111 em solubilizar fosfatos inorgânicos, este trabalho teve por objetivo geral avaliar a possibilidade de inocular no solo esporos ou pellets imobilizados com vista a prolongar sua habilidade de solubilização e averiguar o mecanismo de solubilização de fosfatos inorgânicos de Ca, Al e Fe por este fungo. Os pellets inoculados em meio de cultura agitado proporcionaram maior solubilização dos fosfatos, principalmente o fosfato de Fe por ser de baixa solubilidade. No solo, os pellets livres e imobilizados promoveram as maiores solubilizações de fosfato de Fe e maior produção de CO2. Avaliando-se o efeito da fonte de N, as seguintes proporções foram obtidas na solubilização dos fosfatos de Ca, glicina > Al, nitrato de amônio > Fe, ácido l-glutâmico. Os açúcares que mais solubilizaram os fosfatos foram manitol, maltose e d-galactose. Dentre os metais somente o FeCl3.6H2O promoveu maior solubilização do fosfato de Fe e os metais FeSO4.7H2O e FeCl3.6H2O promoveram maiores solubilizações do fosfato de Ca. As concentrações de álcoois que mais favoreceram a solubilização do fosfato de Fe foram 3 e 4% de etanol e metanol, para o fosfato de Ca foi 3% de etanol. A combinação dos metais com o metanol, indicou que o metanol foi o principal responsável pela solubilização. Fatores como queda do pH, a maior produção de ácidos e o menor crescimento do fungo influíram neste trabalho, principalmente em relação a solubilização do fosfato de Fe. No solo, os pellets solubilizaram quantidades semelhantes de fosfato de Fe que os esporos imobilizados de A. niger, podendo ser utilizados com vantagem devido a sua facilidade de obtenção. / Considering the low P availability in the soil and the high capability of Aspergillus niger F111 in solubilizing inorganic phosphates, this work aimed to evaluate the possibility of inoculating spores or immobilized pellets in the soil to prolong the solubilization capability and study the solubilization mechanism of inorganic calcium phosphate, aluminum phosphate and iron phosphate by this fungus. Pellets inoculated in culture medium under agitation allowed higher phosphate solubilization, especially iron phosphate, which is low soluble. In the soil, free and immobilized pellets allowed the highest solubilization of iron phosphate and CO2 production. Evaluating the effect of N sources, the following proportions were obtained in the solubilization of calcium phosphates, glycine > Al, ammonium nitrate > Fe, l-glutamic acid. The sugars that most solubilized phosphates were mannitol, maltose and d-galactose. Among the metals, only FeCl3.6H2O promoted higher iron phosphate solubilization, and FeSO4.7H2O and FeCl3.6H2O promoted higher solubilization of calcium phosphate. The alcohol concentrations that most favored iron phosphate solubilization were 3 and 4% of ethanol and methanol, while the highest solubilization of calcium phosphate was reached with 3% ethanol. The combination of metals with methanol indicated this alcohol was mainly responsible for solubilization. Factors as pH decrease, higher acid production and lower A. niger growth influenced the results, especially in the solubilization of iron phosphate. In the soil, pellets and immobilized spores solubilized similar amounts of iron phosphate. Pellets are thus preferable because they are more easily obtained.

Submitted by Weslei Diego Pavini null (wesleydiego@gmail.com) on 2017-05-23T14:13:00Z No. of bitstreams: 1 Dissertação mestrado - Weslei D. Pavini.pdf: 7330663 bytes, checksum: a86ba8ec10a0627ea18d3883c094b461 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-05-23T18:18:34Z (GMT) No. of bitstreams: 1 pavini_wd_me_araiq_par.pdf: 737035 bytes, checksum: 22742b425e546a6ef2e994294d7d9349 (MD5) / Made available in DSpace on 2017-05-23T18:18:34Z (GMT). No. of bitstreams: 1 pavini_wd_me_araiq_par.pdf: 737035 bytes, checksum: 22742b425e546a6ef2e994294d7d9349 (MD5) Previous issue date: 2017-05-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Biorreatores têm sido estudados para obtenção de H2, um produto de alto valor agregado usado na indústria química e afim e na produção de energia. Neste trabalho foi desenvolvido um método para análise de compostos orgânicos voláteis (VOCs) produzidos em biorreatores para auxiliar na pesquisa e no controle operacional da produção de H2. Com base nos compostos de interesse foi otimizado um procedimento de microextração líquido-líquido (LLME) para recuperação destes do meio aquoso. Para isto foi usado 400 µL de 1-octanol, um solvente lipofílico e biodegradável, sulfato de sódio e 1,2 mL de amostra. Em seguida foi desenvolvido um método de separação e detecção por cromatografia em fase gasosa acoplada a um detector de ionização em chama (GC-FID). A separação foi feita usando coluna de polietilenoglicol de 30 m de comprimento e hélio como gás de arraste. O tempo de análise total foi de 16 min. Através deste método foi possível extrair, separar e quantificar 12 compostos: acetona, metanol, etanol, 1-propanol, 1-butanol, ácido acético, ácido propiônico, ácido butírico, ácido isovalérico, ácido valérico, ácido capróico e ácido láctico. Todas as curvas analíticas foram validadas usando a análise de variância (ANOVA). Além disso, foram calculadas algumas figuras de mérito, como o limite de detecção, o intervalo de quantificação, a exatidão e a precisão. Foram realizados testes de efeito matriz e estabilidade da amostra. Algumas amostras provenientes dos biorreatores de produção de H2 foram analisadas através do método proposto. O método desenvolvido mostrou-se preciso, exato e tem vasta gama de aplicação. / Bioreactors have been studied to obtain H2, a high value-added product used in the chemical and allied industry and in energy production. In this work a method was developed for the analysis of volatile organic compounds (VOCs) produced in bioreactors to assist in the research and operational control of H2 production. Based on the compounds of interest, a liquid-liquid micro extraction procedure (LLME) was optimized for recovery of these from the aqueous medium. 400 μl of 1-octanol, a lipophilic and biodegradable solvent, sodium sulfate and 1.2 mL of sample were used for this. Next, a separation and detection method was developed by gas chromatography coupled to a flame ionization detector (GC-FID). The separation was done using 30 m polyethylene glycol column and helium as carrier gas. The total analysis time was 16 min. This method was used to extract, separate and quantify 12 compounds: acetone, methanol, ethanol, 1-propanol, 1-butanol, acetic acid, propionic acid, butyric acid, isovaleric acid, valeric acid, caproic acid and lactic acid. All analytical curves were validated using analysis of variance (ANOVA). In addition, some figures of merit were calculated, such as limit of detection, interval of quantification, accuracy and precision. The matrix effect and stability of the samples were also performed. Some samples from the H2 production bioreactors were analyzed using the proposed method. The method developed proved accurate, precise and has a wide range of application.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T14:21:17Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T14:21:17Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP