Os queijos artesanais, elaborados com leite cru, são apreciados por suas características sensoriais peculiares. Com objetivo de assegurar a inocuidade destes produtos, a legislação brasileira estabeleceu padrões microbiológicos sanitários para estes alimentos. Microorganismos probióticos são conhecidos por sua capacidade de modular favoravelmente a microbiota do hospedeiro por meio da produção de substâncias antimicrobianas, em especial, os ácidos orgânicos e bacteriocinas. Assim, o presente estudo buscou avaliar a utilização de micro-organismos probióticos como alternativa para melhorar a qualidade microbiológica de queijos artesanais usando o Queijo Artesanal da Serra da Mantiqueira como modelo. Para tanto, foi incorporada à microbiota do leite uma preparação composta de 16 cepas de micro-organismos probióticos, obtendo-se uma concentração final de 3x106 UFC/ml de leite. A estratégia adotada consistiu em comparar os queijos inoculados com micro-organismos probióticos em relação aos queijos não inoculados (controle), durante o período de maturação de 45 dias, em três estações do ano (inverno, verão e outono). As amostras foram coletadas nos dias 1, 15, 30 e 45 para a determinação dos parâmetros: umidade, pH, concentrações de carboidratos, ácidos orgânicos e análises microbiológicas. Avaliou-se também a composição da microbiota dos queijos pela técnica do pirossequenciamento dos genes do rRNA 16S. Os resultados permitiram verificar que os gêneros predominantes na microbiota dos queijos foram Streptococcus, Lactobacillus e Lactococcus , em diferentes níveis nas três estações do ano. Foi possível observar que a incorporação das culturas probióticas resultou em diferentes efeitos nas estações avaliadas no que se refere às concentrações de carboidratos e ácido cítrico, bem como de ácidos orgânicos ao final dos 45 dias de maturação, possivelmente devido à variabilidade da microbiota verificada nas diferentes estações. No tocante às características microbiológicas, observou-se que, durante o período de maturação, 95% dos queijos confeccionados nas diferentes condições apresentaram padrões de qualidade em conformidade com o estabelecido na legislação, no que se refere às concentrações de coliformes termotolerantes, estafilococos coagulase positivos, Salmonella sp e Listeria sp independentemente da incorporação das culturas probióticas. Entretanto, a adição das culturas probióticas reduziu a carga microbiana de gêneros da família Enterobacter iaceae , em especial Enterobacter , Citrobacter , Klebsiella , Kluyvera e Obesumbacterium durante processo de maturação. Especificamente, o emprego das culturas probióticas resultou em redução do percentual total de Enterobacter iaceae na microbiota dos queijos de 0,41% para 0,17% no verão, e de 12,42% para 6,71% no outono. Neste contexto, a adição de culturas probióticas pode constituir alternativa viável para melhoria da qualidade microbiológica de queijos elaborados com leite cru por meio do incremento do potencial antagônico da microbiota sobre espécies de micro-organismos potencialmente patogênicos, toxigênicos e deteriorantes, além de agregar valor ao produto final. / Artisanal cheeses, made with raw milk, are appreciated for their sensorial profiles, which differentiates them from industrialized cheeses. In order to ensure safety to consumers, Brazilian legislation established microbiological standards for these products. Probiotics are well known for their ability to favorably modulate the host\'s microbiota by producing antimicrobial compounds, mainly organic acids and bacteriocins. Therefore, this study aimed to evaluate the use of probiotic microorganisms as an alternative to improve the microbiological quality of artisanal cheeses through inhibition of contaminating microorganisms, using Mantiqueira Highlands Artisanal Cheese as a model. To do so, a preparation consisting of 16 probiotic strains was added to the milk, at a final concentration of 3x106 CFU/ml. Additionally, the effects of this practice on pH, carbohydrates and organic acids concentrations over a 45 day ripening period were evaluated. Analyses of cheese bacterial community composition were also undertaken by means of 16S rRNA gene pyrosequencing. The strategy consisted of comparing cheeses made with probiotic cultures with a control group, to which no probiotic culture was added. Over a 45 day ripening period, in three seasons (winter, summer and autumn), samples were collected at days 1, 15, 30 and 45 in order to conduct pH, moisture, carbohydrate, organic acids, microbiological and pyrosequencing analyses. The results showed that the addition of probiotic cultures resulted in distinct effects in the different seasons regarding carbohydrate and organic acids concentrations, possibly due to variability in bacterial community composition. The results also demonstrated that 95% of cheeses were deemed acceptable according to Brazilian law regarding coliforms, positive coagulase staphylococci, Salmonella sp. and Listeria sp, regardless of adding probiotics. However, the incorporation of probiotic microorganisms resulted in reduced populations of genera belonging to Enterobacteriaceae family, especially Enterobacter, Citrobacter, Klebsiella, Kluyvera and Obesumbacterium, throughout the whole ripening process. Specifically, the addition of probiotic cultures reduced the total percentage of Entercobacteriaceae from 0,41% to 0,17% in the summer, and from 12,42% to 6,71% in the fall. In this context, the use of probiotic microorganisms may represent a viable alternative for improving microbiological quality of raw milk cheeses by means of incrementing the antagonistic potential of cheese microbiota towards potentially pathogenic and toxigenic microorganisms.

Dois ensaios experimentais foram conduzidos com o objetivo de determinar o efeito dietético da suplementação de acidificantes sobre o desempenho, incidência de diarréia (ensaio 1) e na digestibilidade aparente de nutrientes (ensaio 2). No ensaio 1, com duração de 42 dias, 120 leitões desmamados aos 21 dias foram distribuídos em 8 blocos experimentais com três leitões por baia,foram aplicados cinco tratamentos. Os tratamentos foram: ração sem acidificante, com 1,0% de diformiato de potássio, com 1,0% de ácido fumárico, com 1,0% de ácido cítrico ou com 1,0% de ácido benzóico. No ensaio 2, 10 leitões com peso médio inicial de 16,4 kg foram distribuídos em dois blocos experimentais, cada um com cinco repetições, sob dois tratamentos (ração sem acidificante ou com 1,0% de ácido fumárico). No estudo de desempenho, a adição de ácido fumárico nas rações determinou aumentos (P<0,05) no consumo de ração nos períodos de 0 aos 15 dias, 0 aos 32 dias e ganho de peso de 0 aos 42 dias, quando comparado ao tratamento controle. Não foi observada a ocorrência de diarréia nos leitões nos primeiros 14 dias pós-desmame. No ensaio 2, a adição de 1,0% de ácido fumárico na ração não alterou (P>0,05) os coeficientes de digestibilidade aparente da matéria seca, proteína bruta e fibra bruta, os valores de energia digestível e metabolizável das rações e a taxa de absorção e retenção de nitrogênio. A ausência de diferenças nos coeficientes de digestibilidade aparente dos nutrientes dietéticos com a inclusão do acidificante, provavelmente, deveu-se ao curto período de avaliação. A inclusão de ácido fumárico nas rações de leitões desmamados favoreceu o desempenho dos leitões. / Two experimental assays were conducted in order to evaluate the effect of supplementation of acidifiers in the diets both on performance traits and incidence of diarrhea (assay 1) and on nutrient digestibility (assay 2). In assay 1, which lasted for 42 d, it was used 120 21-days old weaned piglets, distributed in 8 blocks of 3 pigs per pen. There were five evaluated treatments, which consisted of: ration without acidifier, with 1,0% of K-diformate, 1,0% of fumaric acid, 1,0% of citric acid or 1,0% of benzoic acid. In assay 2, 10 pigs with an average weight of 16,4 kg were allocated in two treatments (ration without acidifier or supplemented with 1,0% of fumaric acid) with five replicates each; experimental design was ramdomized complete blocks. In comparison with the control treatment, the addition of fumaric acid in the ration led to an increase in the following parameters: daily feed intake from day 0 to 15 (P< 0,05); daily feed intake and body weight gain from day 0 to 32 (P< 0,05) and from day 0 to 42 d (P< 0,05). There was not treatment effect (P> 0,05) upon feed conversion over the experimental period, and it was not observed the occurrence of diarrhea over the first 14 days after weaning. In assay 2, the addition of 1,0% of fumaric acid in the ration did not modify (P>0,05) the coefficients of apparent fecal digestibility of dry matter, crude protein and crude fiber, the values of digestible and metabolizable energy of the rations and the rates of nitrogen absorption and retention. The absence of differences in the coefficients of the dietary nutrient s apparent digestibilidade with the inclusion of the acidifier, probably, was due to the short evaluation period. The inclusion of fumaric acid in the rations of weaned pigs improved performance of piglets; however, it did not modify the coefficients of apparent fecal digestibility of the nutrients.

This thesis explored the development of a faster and more efficient means of qualitative and quantitative analysis of the products of the nitric acid oxidation of D-glucose and other simple sugars, for the Shafizadeh Rocky Mountain Center for Wood and Carbohydrate Chemistry. During the research, analysis was carried out based on previous work completed in a similar area using two Aminex HPX-87H+ cation-exchange columns at different temperatures, and plumbed in series. Standards were filtered and injected on to the columns, then eluted with 5 mM sulfuric acid. A total run time of 33 minutes enabled the elution of all products and by-products of the reaction. Retention times of standards and the use of spiking helped specify and quantify unknowns in samples from a series of oxidation reactions involving D-glucose and other aldoses. The PrevailTM Organic acid (OA) column was said to provide 'unsurpassed resolution of organic acids'. It was therefore investigated, and a method was developed and refined in order to optimise conditions enabling the column's use for the required analyses. The optimised parameters were established as: ambient temperature with an eluent of 10 mM KH2PO4 adjusted to a pH of 2.1 with phosphoric acid. The sample size was 5 uL with a flow rate of 0.3 mL/min, giving a total run time of approximately 13 minutes. The Aminex HPX-87H+ column method and the PrevailTM OA method were compared to determine the superior method for the analyses intended. While some improvements were made for detection in the PrevailTM OA method, results were not satisfactory. This was due in part to limits imposed on the PrevailTM OA column method, which prevented the use of gradient elution. The Aminex HPX-87H+ column method outlined herein provides superior resolution for the nitric acid oxidation of D-glucose to D-glucaric acid, and in conclusion it is suggested that the Aminex HPX-87H+ column method be used.

Naphthenic acids (NAs) are carboxylic acids found in crude oil and petroleum products. The objectives of the research presented here were to: a) assess the occurrence and fate of NAs in crude oil and refinery wastewater streams; b) evaluate the biotransformation potential and inhibitory effects of NAs under nitrifying, denitrifying and methanogenic/fermentative conditions; c) investigate the factors affecting NA biotransformation under aerobic conditions and the microbes involved; and d) assess the toxicity of individual model NAs using quantitative structure-activity relationships (QSAR) and examine the effect of structure on NA biotransformation potential. NAs are ubiquitous in refinery wastewater streams and the desalter brine was found to be the main source of NAs in refinery wastewater. A commercial NA mixture was not biodegraded under nitrate-reducing or methanogenic/fermentative conditions. NAs were degraded under aerobic conditions by an NA-enriched culture; however, a residual fraction was not degraded under all conditions studied. The results indicated that NAs are not inherently recalcitrant and the residual fraction was due to the individual NA concentrations being below the minimum substrate concentrations at which they are no longer degraded. A fraction of the NA mixture was completely mineralized to carbon dioxide, with the remaining portion biotransformed to more oxidized intermediates. Overall, the results indicated that NAs were degraded under aerobic conditions; however, biological treatment of NA-bearing wastewater will not completely remove NA concentrations and thus, biological treatment must be combined with physical/chemical treatment to achieve complete NA removal.

Anjoner från de tre korta organiska syrorna: acetat, format och MSA är intressanta att mäta då de kan användas för olika sorters miljöstudier. Jonkromatografen vid Institutionen för Geovetenskaper kan för närvarande inte skilja på dessa tre ämnen, därför utvecklades sex nya metoder i detta projekt för att lösa problemet. Metod 5 visade sig vara den bästa, där acetat och format separerades. Resultatet ansågs vara bra, även om MSA inte separerades. Metod 5 testades sedan på ett par naturliga prover; vatten-, snö- och isprover. Alla dessa prover visade en större mängd av format än acetat, som i vissa fall inte ens visades. Resultaten verkade rimliga, inte många av dem stack ut i jämförelse till andra resultat av samma fas. Det ytligaste provet från Lomonosovfonnaglaciären skiljer sig dock ganska mycket i mängden format jämfört med prover från andra djup av denna iskärna, förmodligen på grund av kontamination vid hanteringen av proverna både vid provtagningen och i labbet. MSA kan dock även mätas om man vet mängden acetat och format i provet. Detta görs genom tillsats av kända mängder av MSA till samma prov i efterföljande körningar, för att sedan kunna beräkna koncentrationen av MSA i provet. Problemet med denna metod är att koncentrationen av MSA måste vara tillräckligt hög i kontrast till koncentrationerna av acetat och format för att få tillförlitliga resultat, vilket den inte var i det här projektets analyserade prover. / Anions from three short organic acids: acetate, formate and MSA are interesting to measure since they can be used for different environmental studies. The ion-chromatographer at the Department of Earth Sciences is currently not able to separate these three substances; therefore six new methods were developed in this project to solve this problem. Short organic test 5 ended up to be the best method, where acetate and formate were separated. The result was considered good, even if MSA were not separated. Method 5 was then tested on a couple of natural water, snow and ice samples. All these samples showed a larger amount of formate than of acetate, which in some cases was not even found. The results seemed plausible; not many of them were sticking out compared to others of the same phase. The shallowest sample from the Lomonosovfonna ice cap did however differ quite a lot in amount of formate compared with samples from other depths of this ice core; probably because of contamination which could have occurred at both the ice cap and in the lab during the handling of the samples. MSA can however also be measured if the amount of acetate and formate in the sample is known. This is done by adding known amounts of MSA to the same sample in subsequent runs to then be able to calculate the concentration of MSA in the sample. The problem with the use of this method is that the concentration of MSA needs to be high enough in contrast to acetate and formate in order to get reliable results, which was not the case in the samples measured in this project.

The interface of a zinc-terminated polar zinc oxide surface (0002) with a series of chemisorbed fluorinated benzylphosphonic acids has been studied using density functional theory. The calculations indicate that there is a substantial change in the binding energies and work function modification depending on the binding motif. The results also indicate that there is a pronounced difference in the magnitude and trends of the factors determining the total change in work function. The oxygen core-level binding shifts have been calculated and compared to available experimental data.

Wine sensory attributes are associated with quality of wines. Cabernet Franc did not possess good coloration of its wine. Therefore, in the 2009 and 2010 growing seasons, studies including the sampling of four red wine grape cultivars from the end of flowering throughout the rest of the season and applying treatments to Cabernet Franc grapevines at veraison were commenced to address suitability and color enhancement, respectively. The study examining Cabernet Franc, Cabernet Sauvignon, Chambourcin, and Norton looked at sampling their grapes at two-week intervals from times post-flowering to understand the demands of each cultivar during key stages of berry development, in particular berry maturation post-veraison. The French-American hybrids Chambourcin and Norton were found to accumulate high levels of anthocyanins, also termed high cultivar performance, while the Vitis vinifera L. cultivars of Cabernet Franc and Cabernet Sauvignon remained stable in their anthocyanin content post-veraison. The results of the treatments applied to Cabernet Franc as a possible exogenous amelioration for anthocyanin pigment deficit in this cultivar support use of treatments for improving coloration in Cabernet Franc in Kentucky.

Metabolism is an integrated network of biochemical pathways involving a series of enzymecatalysed anabolic or catabolic reactions in cells. Metabolites are chemical compounds that are involved in or are products of metabolic pathways, and the metabolome is defined as the total complement of all the low molecular weight metabolites present in a cell at any given time. Metabolomics is a relatively new research technology utilised for the global investigation, identification and quantification of the metabolome. Three aims were defined for the metabolomics study presented here: • The use of metabolomics technology to generate new biological information; • Application of the metabolomics technology to gain information on the three natural perturbations, namely the menstrual cycle, pregnancy and aging; and • Reflection on metabolomic studies as a hypothesis-generating approach. I obtained three sets of urine samples from women during their menstrual cycle, samples from sixteen pregnant and eleven non-pregnant women for the second natural perturbation, and data sets from previous investigations on infant and child groups, as well as thirty-two urine samples from adults for the study of the metabolomic profiles due to age. These urine samples were analysed to determine the organic acid metabolite profiles. The metabolites were identified by means of AMDIS and were manually quantified. Data matrixes were compiled, which underwent certain data reduction steps, prior to statistical analysis. Different statistical approaches were used to generate information on these three natural perturbations due to the clear differences between the three experimental groups used. The investigation of the menstrual cycle did not show a distinct difference between the three phases involved in the cycle, whereas the pregnancy perturbation showed a difference between pregnant groups and non-pregnant groups. The most pronounced difference in metabolite profiles were found when the different age groups were compared to one another. Finally a hypothesis on the effect of age on metabolism was defined and an experimental approach was proposed to evaluate this hypothesis. In conclusion three proposals were formulated from this investigation: 1. If it appears that an insufficient number of participants can be generated for a metabolomics study, such a study should be discarded in the interest of a more feasible investigation. 2. It is advisable that a number of appropriate analytical validation parameters should be incorporated in the early stages of a metabolomics study, specifically linked to the context of the perturbation chosen for the investigation. 3. The control and experimental groups should be homogenous that is to say as comparable as possible with regard to age, ethnicity, diet, and gender, lifestyle habits and other possible confounding influences, except for the specific perturbation being studied. In a perfect world this would be possible, specifically when hypothesis formulation, testing and finally the expansion of scientific knowledge is a desired outcome of the investigation. / Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2010.

Metabolism is an integrated network of biochemical pathways involving a series of enzymecatalysed anabolic or catabolic reactions in cells. Metabolites are chemical compounds that are involved in or are products of metabolic pathways, and the metabolome is defined as the total complement of all the low molecular weight metabolites present in a cell at any given time. Metabolomics is a relatively new research technology utilised for the global investigation, identification and quantification of the metabolome. Three aims were defined for the metabolomics study presented here: • The use of metabolomics technology to generate new biological information; • Application of the metabolomics technology to gain information on the three natural perturbations, namely the menstrual cycle, pregnancy and aging; and • Reflection on metabolomic studies as a hypothesis-generating approach. I obtained three sets of urine samples from women during their menstrual cycle, samples from sixteen pregnant and eleven non-pregnant women for the second natural perturbation, and data sets from previous investigations on infant and child groups, as well as thirty-two urine samples from adults for the study of the metabolomic profiles due to age. These urine samples were analysed to determine the organic acid metabolite profiles. The metabolites were identified by means of AMDIS and were manually quantified. Data matrixes were compiled, which underwent certain data reduction steps, prior to statistical analysis. Different statistical approaches were used to generate information on these three natural perturbations due to the clear differences between the three experimental groups used. The investigation of the menstrual cycle did not show a distinct difference between the three phases involved in the cycle, whereas the pregnancy perturbation showed a difference between pregnant groups and non-pregnant groups. The most pronounced difference in metabolite profiles were found when the different age groups were compared to one another. Finally a hypothesis on the effect of age on metabolism was defined and an experimental approach was proposed to evaluate this hypothesis. In conclusion three proposals were formulated from this investigation: 1. If it appears that an insufficient number of participants can be generated for a metabolomics study, such a study should be discarded in the interest of a more feasible investigation. 2. It is advisable that a number of appropriate analytical validation parameters should be incorporated in the early stages of a metabolomics study, specifically linked to the context of the perturbation chosen for the investigation. 3. The control and experimental groups should be homogenous that is to say as comparable as possible with regard to age, ethnicity, diet, and gender, lifestyle habits and other possible confounding influences, except for the specific perturbation being studied. In a perfect world this would be possible, specifically when hypothesis formulation, testing and finally the expansion of scientific knowledge is a desired outcome of the investigation. / Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2010.

Lesinimo bandymas truko 56 dienas ir buvo atliktas su 30 savaičių Hisex Brown linijų derinio 36 vnt. dėsliųjų vištų. Paukščiai buvo suskirstyti į 3 grupes, kiekvienoje grupėje po 12 vištų. Visų grupių vištos buvo lesinamos standartiniais kombinuotaisiais lesalais. Kontrolinės grupės vištos buvo lesinamos tik standartiniais kombinuotaisiais lesalais, į I tiriamosios grupės kombinuotuosius lesalus buvo įmaišyta organinių rūgščių priedo, kurio dozavimas 1,5 kg/t lesalų, į II tiriamosios grupės kombinuotuosius lesalus įterpta organinių rūgščių priedo 2 kg/t lesalų. Lumance priedai – 1,5 kg/t ir 2,0 kg/t – esminės įtakos vištų masės dinamikai nebuvo nustatytas. Minėti priedai mažino vištų dėslumą sumažino 2-4 proc., o lesalų konversijai bei išsaugojimui esminės įtakos nenustatyta. Naudoti Lumance priedai sumažino tyrimų vištų masę 3-5 proc. Lumance priedas 1,5 kg/t lesalų padidino lukšto stiprumą 10 proc., baltymo aukštį 9 proc., Hafo vienetus – 6 proc., lukšto storį – 3 proc., palyginus su kontroline grupe. Lumance priedai omega – 6 ir omega – 3 kiekiui bei santykiui, hypocholesterolemijos/hypercholesterolemijos, peroksidavimosi, aterogeniškumo ir trombogeniškumo indeksams tiek šviežiuose kiaušiniuose, tiek sandėliuotuose 28 dienas esminės įtakos neturėjo. Juslinės šviežių kiaušinių baltymo ir trynio savybės buvo labai artimos, nenustatyta, kad naudoti priedai būtų turėję reikšmingos įtakos kvapo, skonio, spalvos ar tekstūros savybių intensyvumui. Išlaikius kiaušinius 28 paras... [toliau žr. visą tekstą] / The feeding experiment took 56 days and was performed on the 36 Hisex Brown layer fowl of 30 weeks old. Hens were divided into 3 groups of 12 hens in each. The fowl of all 3 groups were fed with a standard composite feed. The fowl in the auditorial group were only fed with the standard composite feed whilst the composite feed of the first investigative group was mixed with an organic acid supplement of a dosage 1,5kg/tn of feed and finally the composite feed of the second investigative group was combined with an organic acid supplement of a dosage 2kg/tn of feed. The influence was not detected of the Lumance supplements (1,5kg/t and 2kg/t) to the body growth of the fowl. The mentioned supplements reduced fowl productivity by 2-4% however the influence was not detected to the conversion of feed and preservation. Used Lumance supplements reduced the body weight of examined fowl by 3-5%. Lumance supplement of 1,5kg/t feed increased the strength of the hull by 10% and the height of albumen by 9%, the units of Haf – by 6% and the thickness of the hull by 3% in comparison with the auditorial group. Lumance accessories omega - 6 and omega - 3 and the quantity proportion hypercholesterolemia/ hypercholesterolemia, peroxidation, atherogenic and thrombogenicity indices both fresh eggs and warehoused for 28 days had no significant influence.The sensual features of yolk and albumen of fresh eggs were very close and it was not established a significant influence of the used supplements... [to full text]