Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 142-152). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 142-152). Also available on the Internet.

Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1922. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed March 17, 2010) Includes bibliographical references (p. 34) and index (leaf 35).

Processing of lignocellulosic biomass for transportation fuels and other biocommodities in integrated biorefineries has been proposed as the future for emerging sustainable economies. Currently bioprocessing strategies are all multi-step processes involving extensive physicochemical pretreatments and costly amounts of exogenous enzyme addition. Consolidated bioprocessing (CBP), or direct microbial conversion, is a strategy that combines all the stages of production into one step, thus avoiding the use of expensive pretreatments and exogenous enzymes that reduce the economic viability of the products produced. With a growing trend towards increased consolidation, most of the reported work on CBP has been conducted with soluble sugars or commercial reagent grade cellulose. For CBP to become practical fermentative guidelines with native feedstocks and purified cellulose need to be delineated through specific substrate characterization as it relates to possible industrial fermentation. By carefully reviewing the fundamentals of biomass pretreatments for CBP, a comparative assessment of the fermentability of non-food agricultural residue and processed biomass was conducted with Clostridium thermocellum DSMZ 1237. Cell growth, and both gaseous and liquid fermentation end-product profiles of C. thermocellum as a CBP processing candidate was characterised. Batch fermentation experiments to investigate the effect of cellulose content, pretreatment, and substrate concentration, revealed that higher yields were correlated with higher cellulose content. Pretreatment of native substrates that increased access of the bacterial cells and enzymes to cellulose chains in the biomass substrate were key parameters that determined the overall bioconversion of a given feedstock to end-products. The contribution of amorphous cellulose (CAC) in different biomass substrates subjected to the same pretreatment conditions was identified as a novel factor that contributed to differences in bioconversion and end-product synthesis patterns. Although the overall yield of end products was low following bioaugmentation with exogenous glycosyl hydrolases from free-enzyme systems and cellulosome extracts. Treatment of biomass substrates with glycosyl hydrolase enzymes was observed to increase the rate of bioconversion of native feedstocks in biphasic manner during fermentation with C. thermocellum. A “quotient of accessibility” was identified as a feedstock agnostic guideline for biomass digestibility. / October 2015

Recombinant Protein G (rPG), an engineered form of streptococcal protein G with a theoretical molecular weight of 22.26 kDa was successfully cloned and expressed in E.coli BL 21(DE3) cells. The albumin binding domain was removed during the gene synthesis to avoid unspecific binding. This recombinant form of protein G contains only the IgG binding domains along with the 6X histidine tag at the N terminal. The removal of non-specific domains maximizes the specificity of IgG binding through the Fc region. The recombinant protein G was purified through heat treatment and using immobilized metal affinity chromatography (IMAC). On an SDS-PAGE gel there was only a single band of the purified preparation which migrated at 32 KDa, however when analyzed by mass spectrometry it was ~22.4 kDa, this phenomenon of retarded migration on SDS-PAGE has been known from previous studies. The production of recombinant protein has also been optimized. The effects of expression temperature, inducer type, inducer concentration and media composition have been investigated. The expression was done at 10 liter scale using the best expression conditions, and the protein was purified to homogeneity, dialyzed and lyophilized. The pure protein was immobilized on a POROS AL (Self Pack® POROS® 20 AL, Applied Biosystems, USA). The immobilized protein IgG binding has been monitored using a VersAFlo system. This system allowed real time monitoring of IgG binding characteristics. / <p></p><p> </p>

No description available.

Six different cotton gin trash silages were studied which varied according to the rehydrating medium (water or whey) and the strain of L. plantarum, if any, used for inoculation. Silages were incubated at 34°C and analyzed at weeks 0, 1, 2, 3, 4, and 8 for counts of lactobacilli, total anaerobes, and sporeforming anaerobes. Biochemical measurements included pH, proximate analysis, volatile fatty acid analysis, and lactic acid analysis. Counts of lactobacilli and total anaerobes followed similar trends in all experimental silages with numbers greatly increasing by the end of week one and then subsequently declining. Counts of sporeforming anaerobes increased ten-fold by the end of the second week. Subsequent counts showed that the water-rehydrated silages maintained this increase whereas the whey silages decreased in numbers to their original magnitude. Whey-rehydrated silages had a significantly lower pH, higher dry matter content, a lower level of fiber, lignin, and cellulose, and a higher concentration of carbohydrate. These silages showed only traces of butyric acid and significantly higher concentrations of lactic acid. Thus the whey, as a rehydrating medium, produced silages of desirable pH and exhibited biochemical parameters indicative of good quality and feeding value. Of the three water-rehydrated silages, one was of obvious poor quality with the other two being questionable. No benefit was seen in using an inoculum of L. plantarum.

No description available.

The basic aim of barley malt breeders and maltsters is to produce malt with optimum fermentability levels. The purpose of this research was to understand and evaluate the effect of wort boiling and autoclaving at varying time periods (30, 45, 60, 90, and 120 min) on malt fermentability. The effect of trub content was also analyzed. Small-scale fermentations were carried out using a ‘Control malt’ and a standard SMA yeast strain. The Apparent Degree of Fermentability (ADF), Turbidity (absorbance at 600nm), and Density (oPlato) were measured at specific time intervals over three day fermentation period and non-linearly modeled. From the results obtained, we suggest that heat treating wort with or without trub, (at 100°C, 121.1°C) for a range of times results in significant decline in the ADF (p<0.05). Free amino nitrogen levels of wort declined significantly with respect to both increase in wort boiling temperature and intervals (p<0.001).

The primary goal of this study was to investigate and compare the fermentation performance of malt produced from eleven Canadian two-row barley varieties grown during the 2007 and 2008 crop seasons. Common malting varieties tested included Harrington, AC Metcalfe, CDC Copeland, CDC Kendall, and feed varieties CDC Dolly, CDC Bold, CDC Helgason and McLeod. As well, three experimental varieties, TR251; TR306; and BM9752D-17, were included in this study due to their varied display of enzymatic activity; of chief interest was the ?-amylase thermal stability. Fermentations were carried out using the standard miniaturized fermentation assay and SMA yeast. Apparent Extract (AE), absorbance, fermentable carbohydrates, and ethanol were measured throughout fermentation. Attenuation, carbohydrate and ethanol data were modeled using the logistic equation, and absorbance data was modeled using the newly developed Tilted Gaussian equation. Results indicate that all but the feed varieties fermented well, achieving low final attenuation, and exhibiting similar fermentation characteristics. Despite only minor performance differences among the top fermenters, it was found that between crop seasons both AC Metcalfe and CDC Copeland fermented as well or better than Harrington, as measured by their respective Apparent Degree of Fermentation (ADF). Harrington displayed substantial performance variation between seasons, while test variety BM9752D-17 fermented the most consistently between years, displaying enhanced fermentation to that of Harrington in 2008. Despite high ?-amylase thermostability, BM9752D-17 did not display enhanced fermentation performance to that of CDC Copeland or AC Metcalfe.