Le manioc (Manihot esculenta Crantz) est une plante, dont les tubercules servent de nourriture de base pour près de 800 millions de personnes sous les tropiques. Malgré sont importance, ce tubercule présente deux inconvénients majeurs qui limitent leur utilisation en alimentation humaine : Une toxicité liée à la présence de composés cyanés, et une faible teneur en protéines. Dans l'optique de lever ces contraintes, plusieurs procédés de transformation ont étés mis au point par l'expérience des populations et des améliorations ont été apportées par la recherche. La plupart de ces procédés incluent une étape critique de fermentation spontanée. Cette étape présente quelques problèmes dus à sa dépendance vis à vis des microorganismes épiphytes. Ces problèmes sont notamment la présence de quantités résiduelles de composés cyanés non négligeables (100 à 170ppm) un temps de ramollissement très long (4 à 5 jours) et des produits dérivés de qualités nutritionnelles et hygiéniques douteuses. Dans l'optique d'améliorer ces procédés traditionnels de rouissage du manioc cyanogène, une centaine de microorganismes ont été isolés des cossettes de manioc séché, sur la base de leurs potentialités à produire la β-glucosidase, l'α-amylase, la pectine hydrolase et la polygalacturonase. Ces enzymes sont les plus impliqués dans les phénomènes biochimiques et physico-chimiques ayant lieu au cours du rouissage du manioc. Ils sont responsables de la dégradation des composés cyanés et du ramollissement des tubercules par dégradation des pectines qui constituent le squelette du tubercule. 60% des microorganismes isolés et identifiés ont été productrices d'α-amylases, 46% de β-glucosidase, et 36%de pectinases. Les capacités des différentes souches sélectionnées à produire ces principaux enzymes, ont ensuite été évaluées. Parmi ces microorganismes, deux se sont avérés particulièrement intéressantes : Une souche de bactérie lactique identifiée comme étant Lactobacillus plantarum avec une activité α-amylase de l'ordre de 17000±100UE/ml, et une activité ß-glucosidase de 2000±300µmol CN-/mn; Une moisissure identifiée comme étant Rhizopus oryzae à activité α-amylase de 20000±500UE/ml et activité pectine hydrolase de 2,3±0,2 µmol COO-/mn/mg. Ces deux souches ont été sélectionnées et utilisées comme ferments en culture mixte avec une biomasse initiale de 106ufc/g manioc frais de Lactobacillus plantarum et 103spores/g manioc frais de Rhizopus oryzae pour la fermentation des tubercules de manioc. Les résultats obtenus ont indiqué une acidification rapide avec un pH avoisinant 3,5±1 après 24 heures de rouissage, un ramollissement plus rapide (12±3mm/5s après 48 heures de rouissage). Mais le rouissage naturel s'est avéré meilleur du point de vue dégradation des composés cyanés. En effet la très forte acidification obtenue avec le ferment dès la 24eme heure, a provoqué un blocage du processus de dégradation des glucosides cyanogénétiques au niveau de la cyanohydrine, composé par ailleurs aussi toxique que l'acide cyanhydrique. Une étude de l'influence de quelques paramètres externes nous ont permis de noter que la température optimale de croissance de Lactobacillus plantarum était de 40±5°C pour un pH optimal de 6 alors que Rhizopus oryzae avait une température optimale de croissance à 30±7°C et un pH optimal de 5. Les essais de production de biomasses, indiquent que le meilleur milieu de multiplication des germes s'est avéré être le milieu CTM de Law et al., avec pour substrat de la farine de son de manioc mélangée au milieu nutritif de Meyer.<br />Dans l'optique de mettre à la disposition des populations ce ferment, des essais de conservation des souches par séchage ont indiqué que le fluide de protection indiqué pour avoir des taux de survies acceptables au terme du séchage était le glycérol, alors que le support le plus adapté a été l'amidon de manioc. On a ainsi obtenu plus de 75±5% de survivants après séchage sur lit convectif à une température de 35°C sous un débit d'air de 10 m3/h pour tous les deux germes. Ce ferment composé de Lactobacillus plantarum (106ufc/g) et Rhizopus oryzae (103spores/g), sur support amidon a induit contrairement aux microorganismes frais, une diminution effective du taux de glucosides totaux résiduels (5% en fin de rouissage) diminution corollaire à l'ajout du NaOH réalisé après la 24ème heure, afin de contourner l'effet néfaste du pH acide sur la dégradation de la cyanohydrine.

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.

Submitted by (edna.saturno@ufrpe.br) on 2016-12-13T18:00:53Z No. of bitstreams: 1 Wilma Cristina Cavalcante dos Santos.pdf: 1360239 bytes, checksum: b9de6c7891a1af74c13ee364d48ca07c (MD5) / Made available in DSpace on 2016-12-13T18:00:53Z (GMT). No. of bitstreams: 1 Wilma Cristina Cavalcante dos Santos.pdf: 1360239 bytes, checksum: b9de6c7891a1af74c13ee364d48ca07c (MD5) Previous issue date: 2014-02-19 / The practice of ensiling of sugarcane without additives has caused marked reduction in the silage nutritional value, due to the rapid fermentation of soluble carbohydrate by yeasts. The use of commercial inoculants containing homo and heterolactic bacteria in the ensilage process becomes an important alternative, however, the efficiency of these inoculants is questionable. Thus, we aimed to evaluate the effect of using two commercial inoculants during the fermentative process of three varieties of sugarcane on the nutritive value, fermentative losses and aerobic stability of the silages. We used a completely randomized design in a 3x3 factorial scheme (three varieties and three treatments) with five repetitions. The treatments were: no inoculant; A Inoculant (Lalsil® sugarcane, L. buchneri, strain NCIMB 40788, 2.5 x 1010 CFU/g) and B Inoculant (Silobac® 5, L. plantarum, strains CH 6072 and L286, 1 x 105 CFU/g). In all treatments, silages showed increased concentrations of NDF and ADF, and reduction in content DM in relative to material before ensiling. Treatment with B inoculant provided higher losses gases, total loss of DM and fractions of ammonia nitrogen, as well as lower levels of IVDMD and TDN, especially for variety RB92579. The A Inoculant improved aerobic stability of silages. The high concentration of sugars (Brix degree) presented by RB92579 seemed to favor the activity of the yeast and, consequently, the fermentative losses. / A prática da ensilagem da cana-de-açúcar sem aditivos tem ocasionado redução acentuada no seu valor nutritivo, em decorrência da rápida fermentação dos carboidratos solúveis pelas leveduras. A utilização de inoculantes comerciais contendo bactérias homo e heteroláticas no processo de ensilagem torna-se uma importante alternativa, porém, a eficiência de tais inoculantes é questionável. Assim, objetivou-se avaliar o efeito da utilização de dois inoculantes comerciais durante o processo fermentativo de três variedades de cana-de-açúcar sobre o valor nutritivo, as perdas fermentativas e a estabilidade aeróbia das silagens. Utilizou-se o delineamento experimental inteiramente casualizado em esquema fatorial 3x3 (três variedades e três tratamentos) com cinco repetições. Os tratamentos foram: Sem inoculante, Inoculante A (Lalsil® cana, L. buchneri, Cepa NCIMB 40788, 2,5 x 1010 UFC/g) e Inoculante B (Silobac® 5, L. plantarum, Cepas CH 6072 e L286, 1x105 UFC/g). Em todos os tratamentos, as silagens apresentaram aumento nas concentrações de FDN e FDA, e redução nos teores de MS em relação ao material antes da ensilagem. O tratamento com o inoculante B proporcionou as maiores perdas por gases, perda total de MS e frações do nitrogênio amoniacal, bem como os menores teores dos NDT e DIVMS, especialmente para variedade RB92579. O Inoculante A melhorou a estabilidade aeróbia das silagens. A elevada concentração de açúcares (grau Brix) apresentada pela variedade RB92579 pareceu favorecer a atividade das leveduras e, consequentemente, as perdas fermentativas.

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.

No description available.

Thesis (MSc)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The equine gastro-intestinal tract (GIT) is a relatively unexplored niche concerning the presence of natural microbiota. Studies have shown that disruption of the microbial population naturally present in the GIT leads to the onset of several forms of gastro-intestinal disorders. To maintain a balanced microbiota, probiotic bacteria need to be administered at specific levels. Beneficial microorganisms assist with digestion of the feed, absorption of nutrients from the GIT, strengthens the immune system and improves the animal‟s growth. Various combinations of lactic acid bacteria (LAB) have been administered to horses, but have failed to benefit the host in any of the latter criteria. The screening for alternative strains with probiotic properties is thus necessary. Two strains (Lactobacillus equigenerosi Le1 and Lactobacillus reuteri Lr1) were originally isolated from horse faeces. Lactobacillus plantarum 423 and Enterococcus mundtii ST4SA, both bacteriocin-producing strains, were isolated from sorghum beer and soy beans, respectively. All four strains survived growth at acidic conditions (pH 3) and the presence of 0.5%, 1.0% and 1.5% (w/v) bile salts. L. reuteri Lr1 was the most resistant to these conditions. All strains adhered to buccal (cheek) epithelium cells sampled from horses. L. equigenerosi Le1 and E. mundtii ST4SA, however, invaded the cells, but without visible signs of disrupting the cells. None of the strains contained genes encoding adhesion to collagen (Ace), resistance to vancomycin A, B and C, or, production of aggregation substance (AS), cytolysin (Cyl) and, non-cytolysin (β hemolysin III), suggesting that they are non-virulent. Of all strains, L. equigenerosi Le1 competed the best with Clostridium sp. C6 for adherence to epithelial cells. L. equigenerosi Le1 and L. reuteri Lr1, showed the highest level of co-aggregation with Clostridium sp. C6. When the four strains were administered to horses over a period of 10 days, L. reuteri Lr1 was retained the longest (8 days) in the GIT. The numbers of viable cells of Clostridium spp. and Salmonella spp. remained constant during administration of the four strains. Blood analyses showed no negative effects from administering the strains. Total white blood cell counts remained unchanged. However, a small but tentative increase in neutrophil and eosinophil cell numbers has been recorded, suggesting that the LAB may have elicited a mild, transient, intolerance reaction. The glucose, lactate and urea levels decreased during administration with the four LAB strains. / AFRIKAANSE OPSOMMING: Die spysverteringstelsel (SVS) van die perd is 'n relatief onbekende nis wat die voorkoms van natuurlike mikrobiota betref. Studies het getoon dat versteuring van die natuurlike mikrobiese populasie in die SVS aanleiding kan gee tot die ontwikkeling van menige vorms van gastro-intestinale ongesteldhede. Om 'n gebalanseerde mikrobiota te verseker, moet probiotiese bakterieë teen 'n spesifieke vlak toegedien word. Voordelige mikroorganismes bevorder vertering en absorpsie van nutriënte vanaf die SVS, versterk die immuunsisteem en bevorder die groei van die dier. Verskeie kombinasies van melksuurbakterieë is reeds aan perde toegedien, maar sonder ooglopende voordele vir die dier. Die soeke na alternatiewe stamme met probiotiese eienskappe is dus noodsaaklik. Twee melksuurbakterieë (Lactobacillus equigenerosi Le1 en Lactobacillus reuteri Lr1) is oorspronklik uit perdemis geïsoleer. Lactobacillus plantarum 423 en Enterococcus mundtii ST4SA, beide bakteriosienproduserende stamme, is afsonderlik van sorghumbier en sojabone geïsoleer. Al vier spesies groei by lae pH (pH 3) en in die teenwoordigheid van 0.5%, 1.0% en 1.5% (m/v) galsoute. L. reuteri Lr1 is die mees bestand onder hierdie toestande. Al vier stamme het aan wang epiteelselle van perde geheg. L. equigenerosi Le1 en E. mundtii ST4SA het egter die epiteelselle binnegedring, maar sonder opsigtelike vernietiging van die selle. Nie een van die stamme besit gene wat kodeer vir aanhegting aan kollageen (Ace), bestandheid teen vankomisien A, B en C, of produksie van, sel-aggregasie (AS), sitolisien (Cyl) en nie-sitolisien (β-hemolisien III), wat daarop dui dat hulle nie-virulent is. Van al die stamme het L. equigenerosi Le1 die beste met Clostridium sp. C6 vir aanhegting aan epiteelselle gekompeteer. L. equigenerosi Le1 en L. reuteri Lr1, het die beste vlak van ko-aggregasie met Clostridium sp. C6 getoon. Met die toediening van 'n kombinasie van die vier stamme aan die perde oor 'n periode van 10 dae, het L. reuteri Lr1 die langste retensie (8 dae) in die SVS getoon. Die aantal lewende selle van Clostridium spp. en Salmonella spp. het konstant gebly tydens toediening van die vier stamme. Toediening van die vier stamme het geen negatiewe effek getoon met resultate verkry van bloed analises nie. Die totale witbloed seltellings het onveranderd gebly. 'n Klein, maar tentatiewe, toename in neutrofiel- en eosinofiel selgetalle is waargeneem, wat daarop dui dat die melksuurbakterieë 'n geringe allergiese reaksie teweeggebring het. Die glukose, laktaat en ureum vlakke het gedaal tydens die toediening van die vier melksuurbakterie stamme.

Thesis (MScAgric (Viticulture and Oenology))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The quality of wine is influenced and determined by various factors, one of which includes the process of malolactic fermentation (MLF). MLF plays an integral role in the flavour and sensory profile of most red wines as well as some white wines like Chardonnay. This process is conducted by lactic acid bacteria (LAB), specifically of the genera Oenococcus, Lactobacillus, Pediococcus and Leuconostoc. Of these, Oenococcus oeni is best adapted to survive in the harsh wine environment. MLF is defined as the conversion of L-malic acid to L-lactic acid and carbon dioxide. The conversion of the dicarboxylic malic acid to the monocarboxylic lactic acid results in a decrease in acidity and an increase in pH, to give a softer mouthfeel and more favourable flavour profile. A further reason for conducting MLF in wine includes the improvement of microbial stability due to the removal of malic acid as a possible substrate for microorganisms. Recently, research focus has shifted to the ability of MLF and LAB to alter the aroma profile of wine via the production and/or modification of certain aroma compounds. In order for wine LAB to conduct MLF, they need to be able to survive the harsh and challenging wine environment. Conditions in South African wines are particularly challenging due to the long, hot ripening seasons resulting in high sugar concentrations which give high ethanol concentrations. Some LAB also struggle to adapt to an environment with high pH and low malic acid concentrations. These factors, combined with the use of sulphur dioxide, cause LAB to struggle in conducting and completing successful MLF. Many of the commercial starter cultures that are currently available contain LAB that have not been isolated from South African wine and are therefore not optimal for use under these challenging wine conditions. Oenococcus oeni is also the single LAB culture present in all commercially available starter cultures. The overriding goal of this study was to create a MLF starter culture containing a mixture of LAB cultures, namely O. oeni and Lactobacillus plantarum, which can successfully convert malic acid to lactic acid, ensure microbial stability, but also make a positive contribution to the wine aroma profile. Lactobacillus plantarum has previously been considered for possible use in a commercial starter culture. The LAB isolates used in this study were selected from the Institute for Wine Biotechnology culture collection as well as isolated from spontaneous MLF. The first objective was to characterise these LAB strains for important traits and for possible use as a MLF starter culture. A total of 23 strains were identified as O. oeni and 19 strains as Lb. plantarum. The identified strains were screened in a synthetic wine medium for their ability to convert malic acid to lactic acid. Based on the LAB strain performance in the synthetic wine medium, seven strains of both O. oeni and Lb. plantarum were selected. These 14 strains were screened for the presence of genes encoding for enzymes responsible for biogenic amine production and were found to contain none of the genes associated with the formation of histamine, tyramine or putrescine. The LAB strains were genetically screened for enzymes associated with aroma modification by LAB during MLF. The enzymes of interest that were screened for included β-glucosidase, esterase, protease and phenolic acid decarboxylase (PAD). The Lb. plantarum strains were found to possess more diverse enzymatic profiles related to aroma than O. oeni. The biggest differences were observed for the presence of β-glucosidase and PAD. The second objective was to perform small-scale fermentations with the individual LAB isolates. The individual isolates were evaluated in Pinotage and based on these results; three strains of each O. oeni and Lb. plantarum were selected for evaluation in mixed culture fermentations. The mixed cultures were evaluated in Pinotage, Shiraz and Cabernet Sauvignon in the 2008 vintage. As a third objective, the wines were also analytically and sensorially evaluated to investigate the changes in the aroma profile that could be attributed to the presence of the mixed LAB isolates. Based on the fermentation data as well as data pertaining to the aroma modification, three mixed cultures were selected for evaluation in the 2009 vintage in Pinotage, Cabernet Sauvignon and Chardonnay. The mixed cultures were able to successfully complete MLF in fermentation periods comparable to that of a commercial culture used as control. The different LAB cultures had distinct and diverse effects on the wine aroma profile. The O. oeni strain played a larger role in the ester concentration present after MLF, while the Lb. plantarum strain had a larger effect on the higher alcohol and volatile fatty acid concentration upon completion of MLF. The results generated by this novel study clearly indicate the potential of a mixed LAB starter culture for conducting MLF. The mixed cultures successfully completed MLF and made a positive contribution to the wine aroma profile. / AFRIKAANSE OPSOMMING: Die kwaliteit van wyn word beïnvloed en bepaal deur verskeie faktore en wynbereidings prosesse, wat die proses van appelmelksuurgisting (AMG) insluit. AMG speel ’n integrale rol in die sensoriese profiel van meeste rooiwyne, sowel as sommige witwyne soos Chardonnay. AMG word gedefinieër as die omskakeling van L-appelsuur na L-melksuur en koolstofdioksied. Hierdie omskakeling kan toegeskryf word aan die teenwoordigheid van melksuurbakterieë (MSB), spesifiek spesies van die genera Oenococcus, Lactobacillus, Pediococcus en Leuconostoc. Vanuit hierdie wyn MSB, is Oenococcus oeni die spesies wat die beste aanpas en oorleef onder stresvolle wyn kondisies. Die omskakeling van appelsuur, ’n dikarboksielsuur, na melksuur, ’n monokarboksielsuur, lei tot ‘n vermindering in suurheid en ’n verhoging in pH. Hierdie vermindering in suurheid gee ’n sagter en meer geronde mondgevoel aan die wyn en dra by tot ‘n meer aangename geurprofiel. ’n Verdere rede vir AMG in wyn is om mikrobiese stabiliteit te verseker deurdat appelsuur verwyder word as ’n moontlike koolstof substraat vir mikroörganismes. Onlangs het navorsing begin fokus op AMG en die vermoë van MSB om die aroma profiel van wyn te beïnvloed deur die produksie/modifisering van sekere aroma komponente. Vir MSB om AMG te kan deurvoer, moet hulle kan oorleef in die stresvolle wynomgewing. Wyntoestande in Suid-Afrika is veral uitdagend vir die oorlewing van mikroörganismes as gevolg van lang, warm somers wat lei tot ’n matriks met ’n hoë suikerkonsentrasie en wyn met ’n hoë etanolkonsentrasie. ‘n Omgewing met ‘n hoë pH en lae appelsuur konsentrasie, kan ook bydrae tot stresvolle kondisies vir MSB. Hierdie parameters, tesame met die gebruik van swaweldioksied, maak dit moeilik vir MSB om AMG te inisieer en te voltooi. Sommige van die kommersiële aanvangskulture wat tans beskikbaar is, bevat nie MSB wat onder Suid-Afrikaanse wyntoestande geïsoleer is nie en daarom is dit nie altyd optimaal vir gebruik nie. Oenococcus oeni is ook die enkele MSB kultuur wat in alle kommersiële kulture gebruik word. Die hoofdoelwit van hierdie studie was om ’n potensiële kommersiële aanvangskultuur te ontwikkel wat ‘n mengsel van MSB bevat. Hierdie aanvangskultuur moet AMG suksesvol kan voltooi, mikrobiologiese stabiliteit bevorder en steeds die wynaroma positief kan beïnvloed. Bakterierasse van O. oeni en Lb. plantarum is geselekteer vir gebruik in hierdie studie. Lactobacillus plantarum het reeds in vorige studies potensiaal getoon as ‘n moontlike aanvangskultuur. Die MSB isolate vir hierdie studie is geselekteer uit die Instituut vir Wynbiotegnologie se kultuurversameling en geïsoleer uit spontane AMG fermentasies. Die eerste doelwit was om hierdie MSB isolate te karakteriseer vir belangrike eienskappe en die moontlike gebruik as ’n kommersiële AMG aanvangskultuur. ‘n Totaal van 23 O. oeni en 19 Lb. plantarum isolate is geïdentifiseer. Hierdie isolate is in ’n sintetiese wynmedium geëvalueer vir hul vermoë om appelsuur na melksuur om te skakel. Op grond van hul reaksie in die sintetiese wynmedium, is sewe isolate van elk van die O. oeni en Lb. plantarum geselekteer. Hierdie 14 isolate is ondersoek vir die teenwoordigheid van die gene wat kodeer vir biogeenamien produksie en daar is gevind dat geen van die isolate enige van die biogeenamien gene wat ondersoek is, naamlik histamien, tiramien en putresien besit nie. Die MSB isolate is geneties ondersoek vir die teenwoordigheid van dié gene wat kodeer vir ensieme wat die aromaprofiel tydens AMG beïnvloed. Dié ensieme sluit β-glukosidase, esterase, protease, fenoliese suurdekarboksilase en sitraatliase in. Daar is gevind dat die Lb. plantarum isolate meer diverse ensiemprofiele as O. oeni besit. Die grootste verskille in die ensiemprofiele kan toegeskryf word aan die teenwoordigheid van β-glukosidase en fenoliese suurdekarboksilase. Die tweede doelwit was om kleinskaalse AMG fermentasies met die individuele MSB isolate uit te voer. Die individuele isolate is in Pinotage geëvalueer. Volgens hierdie resultate is drie isolate van elk van die O. oeni en Lb. plantarum geselekteer om in gemengde kulture getoets te word. Die gemengde kulture is in Pinotage, Shiraz en Cabernet Sauvignon in 2008 geëvalueer. As ’n derde doelwit is hierdie wyne ook analities en sensories geëvalueer om die veranderinge in die aromaprofiele as gevolg van die teenwoordigheid van die MSB te ondersoek. Op grond van die fermentasiedata, sowel as die data oor die aromaveranderinge, is drie gemengde kulture geselekteer vir evaluering in Pinotage, Cabernet Sauvignon en Chardonnay in 2009. Die gemengde kulture kon AMG suksesvol voltooi met fermentasietempo’s wat vergelykbaar was met dié van ‘n kommersiële AMG kultuur wat as kontrole gebruik is. Die verskillende MSB kulture het spesifieke en uiteenlopende uitwerkings op die wynaroma gehad. Die O. oeni isolaat in die gemengde kultuur blyk ‘n belangriker rol te speel in die esterkonsentrasie na AMG, terwyl die Lb. plantarum isolaat ’n groter effek het op die hoër alkohol en vlugtige vetsuurinhoud na AMG. Die resultate wat deur hierdie unieke studie gegenereer is, gee ’n aanduiding van die potensiaal van ’n gemengde MSB aanvangskultuur vir AMG. Die gemengde kulture kon AMG suksesvol voltooi en ‘n positiewe bydrae tot die aromaprofiel van die wyn lewer.

O presente trabalho teve o objetivo de avaliar fatores associados à ensilagem da cana-de-açúcar (Saccharum officinarum L.), com destaque para a aplicação de aditivos químicos e microbianos, sobre a composição químico-bromatológica, perdas fermentativas, digestão de nutrientes e desempenho de bovinos de corte. No primeiro experimento, avaliaram-se variedades de cana-de-açúcar, idades de colheita, tempos de armazenamento das silagens e inclusão de uréia como aditivo na ensilagem, sobre composição das silagens, perdas e parâmetros fermentativos. O experimento foi realizado em esquema fatorial 3x2x2x2, usando-se silos experimentais para confecção das silagens. A composição de nutrientes das silagens foi afetada pelos fatores testados. Silagens da variedade IAC86-2480 apresentaram menor teor de fração fibrosa e de matéria seca, e maior digestibilidade in vitro em relação à variedade IAC87-3184. Plantas colhidas aos 15 meses proporcionaram perdas reduzidas de MS. A aplicação de uréia nas ensilagens foi efetiva em reduzir as perdas totais de MS, e não alterou os teores de etanol ou ácido acético, e elevou o teor médio de ácido lático das silagens. Em um segundo experimento foram avaliados os aditivos químicos uréia e benzoato de sódio, e os microbianos Lactobacillus plantarum (LP) e L. buchneri (LB) na ensilagem da cana-de-açúcar, bem como a cana-de-açúcar ensilada sem aditivos, em rações para bovinos providos de cânula, em ensaio de digestão. Os aditivos aplicados alteraram a composição e as recuperações de MS das silagens. O consumo de MS, digestibilidade aparente de nutrientes e comportamento ingestivo dos animais não foram alterados pelos tratamentos testados. Os parâmetros ruminais foram afetados de forma moderada pelos tratamentos experimentais, com concentrações molares médias dos ácidos acético, propiônico e butírico de 60,9; 19,3 e 10,2 mM, respectivamente. Os tratamentos com uréia, LB e benzoato de sódio elevaram moderadamente a degradabilidade efetiva da MS das silagens. Em uma terceira fase, avaliou-se a silagem de cana sem aditivos e silagens contendo doses de LB em rações para bovinos de corte em confinamento. Foram usados 56 tourinhos Nelore e Canchim, alimentados com rações contendo 45% de volumoso. A inoculação com LB alterou de forma moderada a composição das silagens. A silagem controle apresentou teor de etanol três vezes superior aos tratamentos inoculados (1,53 vs 0,45% da MS). A adição de ingredientes concentrados às silagens foi efetiva em melhorar substancialmente as variáveis de estabilidade aeróbia. Silagens aditivadas proporcionaram elevação na ingestão (23,0%) e no ganho de peso dos animais (12,7%), em relação às rações com silagem controle. O comportamento ingestivo dos animais experimentais foi afetado pelos tratamentos, sendo que rações contendo silagem controle necessitaram de maior tempo para ingestão, ruminação e mastigação, em relação aos tratamentos inoculados. A presença de aditivos na ensilagem da cana-de-açúcar foi efetiva em controlar perdas e preservar o valor nutritivo da forragem conservada. / The goal of this trial was to evaluate ensiling associated factors influencing sugar cane (Saccharum officinarum L.)silages, mainly the use of chemical and microbial additives on the chemical composition, fermentative losses, nutrient digestion and performance of beef cattle. On the first trial, sugar cane varieties were evaluated across harvesting forage ages, storage time and the addition of urea over the chemical composition, fermentative parameters and losses. A factorial 3x2x2x2 design was applied upon experimental silos. The nutrient composition of silages was affected by the studied factors. The silages from IAC86-2480 variety showed lower fiber and dry matter contents and higher in vitro digestibility contents than the silage made of IAC87-3184 variety. Plants that were cut at the age of 15 months led to lower DM losses. The urea addition on ensiling was effective on decreasing total DM losses and did not change the ethanol or acetic acid contents, however increased the mean lactic acid content of silages. On a second trial, the chemical additives, urea and Na-benzoate, were evaluated and the microbial inoculants Lactobacillus plantarum (LP) and L. buchneri were also studied on sugar cane ensiling, compared to the control sugar cane silage, by using ruminally cannulated steers fed TMR rations in a digestion trial. The additives altered the composition and the DM recovery rate of the silages. Overall DM intake, apparent in vivo digestibilities and animal behavior were not affected by treatments. The ruminal parameters were slightly affected by treatments, which averaged molar concentrations of acetic, propionic and butyric acids of 60.9, 19.3 and 10.2 mM, respectively. The urea, LB and Na-benzoate treatments promoted moderate increase on DM effective degradabilities of silages. On the third trial, sugar cane silage without additives and LB added silages were studied on the feedlot beef cattle rations. Fifty six Nellore or Canchim beef bulls were assigned to treatments and fed with 45% forage rations. The LB silages had small changes on the chemical composition and the control silage showed a three times increased content of ethanol when compared to inoculated silages (1.53 vs 0.45% of DM). The concentrates added to silages were effective on improving the aerobic stability parameters. The rations containing LB added silages provided increase on the DM intake (23.0%) and daily weight gain of animals (12.7%), when compared to the control silage ration. The ingestive behavior of experimental bulls was affected by treatments, where control silage ration showed increased feeding, rumination and chewing time, when compared to the inoculated silages. The additives on sugar cane ensiling were effective to prevent losses and to preserve the nutritive value of ensiled forage.

Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-07-28T13:06:12Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_EfeitoUsoDiferentes.pdf: 239802 bytes, checksum: 5b39de29c260f7db7fb4293678fffc0e (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-08-28T14:29:13Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_EfeitoUsoDiferentes.pdf: 239802 bytes, checksum: 5b39de29c260f7db7fb4293678fffc0e (MD5) / Made available in DSpace on 2014-08-28T14:29:13Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_EfeitoUsoDiferentes.pdf: 239802 bytes, checksum: 5b39de29c260f7db7fb4293678fffc0e (MD5) Previous issue date: 2008 / Na conservação de alimentos para animais, os inoculantes microbianos são empregados na busca da melhoria do padrão de fermentação de silagens, por meio do estímulo ao desenvolvimento populacional dos microrganismos benéficos deste processo conservativo, como acontece para as bactérias produtoras de ácido lático, em detrimento a inibição dos microrganismos indesejáveis, tais como leveduras e clostrídios. O estudo proposto avaliou o efeito do uso de diferentes inoculantes microbianos à fresco e liofilizados utilizando a cultura do sorgo [Sorghum bicolor (L.) Moench], como matéria-prima para ensilagem, a fim de indicar a possibilidade do emprego de inoculantes microbianos desenvolvidos no nosso país. Foram realizados dois experimentos, em um mesmo silo, Experimento 1 (tratamentos com inoculantes liofilizados, na região superior do silo) e Experimento 2 (tratamentos com inoculantes à fresco, na região inferior do silo), com cinco tratamentos e três repetições por silo, sendo os tratamentos caracterizados como controle (sem inoculante), inoculante microbiano comercial (IC) e distintos inoculantes confeccionados à partir de bactérias láticas isoladas da planta de sorgo: Lactobacillus plantarum, Lactobacillus paracasei e Lactobacillus rhamnosus. Quando da ensilagem, foram utilizados três silos experimentais de madeira, que foram abertos em distintos períodos, ou seja, 1, 3 e 28 dias após a ensilagem. Foi utilizado o delineamento experimental em parcelas subdivididas no tempo, no qual os três períodos de abertura foram às parcelas e os cinco tratamentos as subparcelas, em delineamento inteiramente casualizado. No experimento 1, os teores de fibra em detergente neutro (FDN) e fibra em detergente ácido (FDA) sofreram efeito dos inoculantes microbianos no 3º e 28º dia de abertura dos silos, obtendo menores valores nos tratamentos IC e LPP (L. plantarum + L. paracasei. No experimento 2, os teores de FDN, apresentaram efeito no 28º dia de abertura do silo, demonstrando que os tratamentos IC e LPP diferiram entre si, sendo estatisticamente iguais aos demais. A combinação dos isolados microbianos liofilizados de L. plantarum e L. paracasei mostrou potencial para uso prático, pois foi tão efetivo quanto o tratamento IC. / In the conservation of animal feed, the microbial inoculants are used in pursuit of improving the standard fermentation of silages, by encouraging the population development of the beneficial microorganisms in this process conservative, as the bacteria that produce lactic acid, rather than using inhibition of undesirable microorganisms such as yeasts and clostridia. The proposed study evaluated the effect of using different microbial inoculants to using fresh and freeze-dried sorghum [Sorghum bicolor (L.) Moench], as raw material for silage, to indicate the possibility of using microbial inoculants developed in the Brazil country. Were conducted two experiments in the same silo, Experiment 1 (treatment with freeze-dried inoculants in the upper region of the silo) and Experiment 2 (treatment with inoculants to cool in the lower silo), with five treatments and three replicates per silo the treatments being characterized as a control (without inoculum), commercial inoculant (IC) and the different inoculants made from lactic acid bacteria isolated from the sorghum plant: Lactobacillus plantarum, Lactobacillus paracasei and Lactobacillus rhamnosus. When silage were used three experimental silos of wood, which were opened at different periods, 1, 3 and 28 days after ensiling. We used the experimental design in split plot in time, in which the three periods were open on plots and subplots the five treatments in a completely randomized design. In experiment 1, the levels of neutral detergent fiber (NDF) and acid detergent fiber (ADF) had the effect of microbial inoculants on the 3rd and 28th day of opening the silos, getting lower values in treatments IC and LPP (L. plantarum + L. paracasei. In experiment 2, NDF, had an effect on the 28th day of opening of the silo, showing that the IC and LPP treatments differed significantly, being statistically equal to others. The combination of freeze-dried microbial isolates of L. plantarum and L. paracasei showed potential for practical use because it was so effective as treatment failure.