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.

This study is concerned with certain factors affecting the content of lactobacillic acid in Lactobacillus plantarum. Three main areas of investigation are reported herein. The effects of both the oxygen tension and the pH of the culture medium on the accumulation of lactobacillic acid were determined. In addition, monolayer studies were conducted to determine the influence of cyclopropane fatty acid content on the molecular packing of membrane lipids.

Foram realizados dois experimentos para avaliação de aditivos microbianos na ensilagem de forragens tropicais. No primeiro experimento avaliou-se o efeito de doses crescentes de Lactobacillus buchneri, em diferentes tempos de armazenamento, sobre o valor nutritivo, perfil fermentativo e estabilidade aeróbia de silagens de milho. No segundo experimento avaliou-se o efeito de L. buchneri, de forma exclusiva, ou em combinação com Lactobacillus plantarum, em silagens de milho, cana-de-açúcar e capim elefante cv. Napier. O tratamento das silagens de milho com L. buchneri não afetou a contagem de fungos filamentosos, com decréscimo nas contagens com maiores tempos de armazenamento. Os teores de ácido lático decresceram com o aumento da dose de L. buchneri. Os maiores períodos de armazenamento resultaram em decréscimo na contagem de BAL, e maiores valores de pH. O tempo de armazenamento diminuiu as leveduras na silagem de milho. Maiores tempos de armazenamento propiciaram maiores tempos para atingir a temperatura máxima e a perda da estabilidade aeróbia. As silagens com doses superiores de L. buchneri apresentaram perda de estabilidade em momento posterior às silagens dos tratamentos controle e LB1x105. O maior tempo de armazenamento da silagem de milho resultou em maior valor nutritivo e perfil microbiológico favorável quanto à fermentação e estabilidade em aerobiose. Inoculação com L. buchneri (NCIMB 40788) reduz a sobrevivência de leveduras durante a fase de armazenamento e o crescimento durante a exposição ao oxigênio, melhorando a estabilidade aeróbia da silagem em ambiente tropical. Doses mais elevadas poderiam compensar parcialmente o menor tempo de armazenamento das silagens. No segundo experimento, o tratamento das silagens de milho com L. buchneri (LB), exclusivamente, ou associado com L. plantarum (LB+LP) não afetou as variáveis relacionadas com o valor nutritivo das silagens. As concentrações de ácido acético nas silagens de milho foram superiores no tratamento controle. Nas silagens de cana-de-açúcar, o tratamento LB apresentou maiores teores de MS e DVIVMO. O tratamento controle apresentou maior população de bactérias ácido láticas, e menor valor de pH. A silagem de cana-de-açúcar sem aditivo atingiu o pico de temperatura após o tratamento LB, sendo esse pico superior na silagem aditivada. Foram observadas menores perdas de matéria seca e produção de gases nas silagens aditivadas, resultando assim em maior recuperação de MS no tratamento LB. Foi observado maior tempo para atingir a temperatura máxima e menor acúmulo de temperatura até o quinto dia de exposição aeróbia no tratamento controle. A temperatura máxima atingida durante a exposição aeróbia foi superior no tratamento LB. Nas silagens de capim, as silagens do tratamento LB+LP apresentaram maiores teores de MS, e menor teor de PB. Foi observada maior população de bactérias ácido láticas nas silagens do tratamento LB+LP. A inoculação com L. buchneri, sozinho, ou em associação com L. plantarum não foi eficiente em melhorar a qualidade e estabilidade aeróbia das forragens avaliadas. / Two trials were conducted for the evaluation of microbial additives on tropical forages ensiling. At the first trial the effect of increasing L. buchneri doses, and different storage periods on the fermentation profile, aerobic stability and nutritive value of corn silage were evaluated. At the second trial the effect of L. buchneri with or without L. plantarum was evaluated on the fermentation profile, aerobic stability and nutritive value of corn, sugarcane and tropical grass silages. Silages inoculation with L. buchneri did not affect the filamentous funghi counts, with decreased counts with higher storage periods. Lactic acid content was influenced only by treatment, with decrease in concentrations as the L. buchneri dose increased. Lactic acid bacteria, yeasts, pH, butyric and acetic acid were influenced by both treatment and storage period. Higher storage periods resulted in decreased LAB counts and higher pH values. Storage time decreased yeast count in corn silage. For the dry matter losses, gas losses and maximum temperature there was no treatment effect, only storage period effect, decreasing along time. It was observed an increase in effluent production with higher storage time. Time to reach maximum temperature, AC5 and AC10 were influenced by both treatment and storage period. Higher storage periods resulted in higher time to reach the maximum temperature and to break the aerobic stability. Silages with the higher L. buchneri doses showed stability breakdown after control and LB1x105 silages. The higher storage period of corn silages resulted in higher nutritive value and microbial profile favorable to the fermentation and stability during aerobic exposure. Inoculation with Lactobacillus buchneri (NCIMB 40788) reduces the survival of yeasts during the storage phase, and its growth during oxygen exposure, improving silage aerobic stability in tropical regions. Higher doses could partly compensate the lower storage time in silages. In the second trial, inoculation of corn silages with L. buchneri (LB), alone or in association with L. plantarum (LB+LP) did not affect the variables related to the silage nutritive value. Acetic acid content of corn silages was higher for the control treatment. In sugarcane silages, LB treatment showed higher DM content and IVTOMD. Control treatment showed higher lactic acid bacteria counts, and lower pH. Sugarcane silage with no additive reached temperature peak after LB treatment, with this peak being higher at the additivated silage. There were observed lower dry matter losses and gas production in LB silages, resulting in higher dry matter recovery. It was observed higher time to reach maximum temperature and lower temperature accumulation until fifth day of aerobic exposure for the control treatment. Maximum temperature reached during aerobic exposure was higher for LB treatment. In tropical grass silages, LB+LP silages showed higher DM and lower CP contents. It was observed higher lactic acid bacteria in LB+LP treatment. Inoculation with L. buchneri, alone or in association with L. plantarum was not efficient in improving quality and aerobic stability of evaluated forages.

The purpose of the project was to exam steams ability to sterilize carrots infected withLactobacillus plantarum. The project was a cowork with Brämhults Juice AB. They hadobserved an increase of Lactobacillus in the production of carrot juice during the summer. Tokeep the flavour of fresh fruits, the juice is treated carefully with heat. This means that thejuice only stays fresh for a few days, around two weeks for an unopened package and threedays for an opened package.In an attempt to remove the remaining Lactobacillus of the carrots, steam is tested as an extrastep in the production of juice. During the project it was found that it is difficult to reach thewanted temperature of above 100°C, when the steam is generated under pressure. When thesteam was released in normal pressure, a decrease in temperature occurred that were so largethat the steam had a temperature of only 40°C. At the second treatment the steam wasgenerated at 1,8 bar pressure and 130°C, the steam then decreased to 80°C.At the third and last treatment the steam was generated under normal pressure and atemperature of 90°C was reached. At this temperature an 96,5% sterilization occurred after 15seconds of steam treatment. This is not enough for Brämhults Juice, since they need only afew percent surviving Lactobacills after 6 seconds. / Uppsatsnivå: C

Foram realizados dois experimentos para avaliação de aditivos microbianos na ensilagem de forragens tropicais. No primeiro experimento avaliou-se o efeito de doses crescentes de Lactobacillus buchneri, em diferentes tempos de armazenamento, sobre o valor nutritivo, perfil fermentativo e estabilidade aeróbia de silagens de milho. No segundo experimento avaliou-se o efeito de L. buchneri, de forma exclusiva, ou em combinação com Lactobacillus plantarum, em silagens de milho, cana-de-açúcar e capim elefante cv. Napier. O tratamento das silagens de milho com L. buchneri não afetou a contagem de fungos filamentosos, com decréscimo nas contagens com maiores tempos de armazenamento. Os teores de ácido lático decresceram com o aumento da dose de L. buchneri. Os maiores períodos de armazenamento resultaram em decréscimo na contagem de BAL, e maiores valores de pH. O tempo de armazenamento diminuiu as leveduras na silagem de milho. Maiores tempos de armazenamento propiciaram maiores tempos para atingir a temperatura máxima e a perda da estabilidade aeróbia. As silagens com doses superiores de L. buchneri apresentaram perda de estabilidade em momento posterior às silagens dos tratamentos controle e LB1x105. O maior tempo de armazenamento da silagem de milho resultou em maior valor nutritivo e perfil microbiológico favorável quanto à fermentação e estabilidade em aerobiose. Inoculação com L. buchneri (NCIMB 40788) reduz a sobrevivência de leveduras durante a fase de armazenamento e o crescimento durante a exposição ao oxigênio, melhorando a estabilidade aeróbia da silagem em ambiente tropical. Doses mais elevadas poderiam compensar parcialmente o menor tempo de armazenamento das silagens. No segundo experimento, o tratamento das silagens de milho com L. buchneri (LB), exclusivamente, ou associado com L. plantarum (LB+LP) não afetou as variáveis relacionadas com o valor nutritivo das silagens. As concentrações de ácido acético nas silagens de milho foram superiores no tratamento controle. Nas silagens de cana-de-açúcar, o tratamento LB apresentou maiores teores de MS e DVIVMO. O tratamento controle apresentou maior população de bactérias ácido láticas, e menor valor de pH. A silagem de cana-de-açúcar sem aditivo atingiu o pico de temperatura após o tratamento LB, sendo esse pico superior na silagem aditivada. Foram observadas menores perdas de matéria seca e produção de gases nas silagens aditivadas, resultando assim em maior recuperação de MS no tratamento LB. Foi observado maior tempo para atingir a temperatura máxima e menor acúmulo de temperatura até o quinto dia de exposição aeróbia no tratamento controle. A temperatura máxima atingida durante a exposição aeróbia foi superior no tratamento LB. Nas silagens de capim, as silagens do tratamento LB+LP apresentaram maiores teores de MS, e menor teor de PB. Foi observada maior população de bactérias ácido láticas nas silagens do tratamento LB+LP. A inoculação com L. buchneri, sozinho, ou em associação com L. plantarum não foi eficiente em melhorar a qualidade e estabilidade aeróbia das forragens avaliadas. / Two trials were conducted for the evaluation of microbial additives on tropical forages ensiling. At the first trial the effect of increasing L. buchneri doses, and different storage periods on the fermentation profile, aerobic stability and nutritive value of corn silage were evaluated. At the second trial the effect of L. buchneri with or without L. plantarum was evaluated on the fermentation profile, aerobic stability and nutritive value of corn, sugarcane and tropical grass silages. Silages inoculation with L. buchneri did not affect the filamentous funghi counts, with decreased counts with higher storage periods. Lactic acid content was influenced only by treatment, with decrease in concentrations as the L. buchneri dose increased. Lactic acid bacteria, yeasts, pH, butyric and acetic acid were influenced by both treatment and storage period. Higher storage periods resulted in decreased LAB counts and higher pH values. Storage time decreased yeast count in corn silage. For the dry matter losses, gas losses and maximum temperature there was no treatment effect, only storage period effect, decreasing along time. It was observed an increase in effluent production with higher storage time. Time to reach maximum temperature, AC5 and AC10 were influenced by both treatment and storage period. Higher storage periods resulted in higher time to reach the maximum temperature and to break the aerobic stability. Silages with the higher L. buchneri doses showed stability breakdown after control and LB1x105 silages. The higher storage period of corn silages resulted in higher nutritive value and microbial profile favorable to the fermentation and stability during aerobic exposure. Inoculation with Lactobacillus buchneri (NCIMB 40788) reduces the survival of yeasts during the storage phase, and its growth during oxygen exposure, improving silage aerobic stability in tropical regions. Higher doses could partly compensate the lower storage time in silages. In the second trial, inoculation of corn silages with L. buchneri (LB), alone or in association with L. plantarum (LB+LP) did not affect the variables related to the silage nutritive value. Acetic acid content of corn silages was higher for the control treatment. In sugarcane silages, LB treatment showed higher DM content and IVTOMD. Control treatment showed higher lactic acid bacteria counts, and lower pH. Sugarcane silage with no additive reached temperature peak after LB treatment, with this peak being higher at the additivated silage. There were observed lower dry matter losses and gas production in LB silages, resulting in higher dry matter recovery. It was observed higher time to reach maximum temperature and lower temperature accumulation until fifth day of aerobic exposure for the control treatment. Maximum temperature reached during aerobic exposure was higher for LB treatment. In tropical grass silages, LB+LP silages showed higher DM and lower CP contents. It was observed higher lactic acid bacteria in LB+LP treatment. Inoculation with L. buchneri, alone or in association with L. plantarum was not efficient in improving quality and aerobic stability of evaluated forages.

Thèse de doctorat : Sciences de la vie et de la santé : Lille 1 : 2001. / Résumé en français et en anglais. Textes en français et en anglais. Bibliogr. f. 232-270. Notes bibliogr.