Clostridial fermen[t]ation of high energy sorghum /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1989.
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| Subjects: | |
| Online Access: | Link to ProQuest copy Link to OAKTrust copy ProQuest, Abstract |
| Abstract: | Pretreatment of biomass has been shown to increase the efficiency of microbial conversion of lignocellulose to energy or chemicals. Most chemical and physical pretreatments, however, are too expensive for practical application. Biological pretreatment during ensilage storage offers the potential for a low cost pretreatment process for herbaceous biomass. A number of cellulolytic microorganisms occurring naturally in silages or inoculated into the biomass during ensiling could result in significant hydrolysis of lignocellulose during storage prior to conversion to the final end products. The overall objective of this research was to induce clostridial fermentation in sorghum during ensiling through either manipulation of enviromental conditions or inoculation with clostridium bacteria. The first objective was to determine whether environmental conditions can influence the natural microorganism's population distribution during ensiling, thus leading to clostridial fermentation. The second objective was to determine whether cellulolytic clostridia can compete with lactic acid bacteria in the ensiling process, resulting in a clostridial fermentation. Two studies were conducted to investigate these two objectives. Three levels of water soluble sugars ranging from 180g/kg D.M. to 15g/Kg D.M. and five levels of moisture contents ranging from 58% to 81% were used in the first part of this investigation. The fermentation types were generally heterolactic acid fermentation though sporadic clostridial fermentations were observed. The major products from the fermentations were lactic acid, acetic acid, ethanol, and mannitol. Although the effects of water soluble sugar and moisture content were highly significant for the amount of lactic acid and total products in the fermentations, the two factors were not enough to induce cellulolytic clostridial fermentation. Forage fiber analysis and analysis of variance of the data showed that the cell wall was not decomposed in lactic acid bacteria dominated fementations. In the second study, Clostridium celluloyticum inoculum was used to trigger clostridial fermentation in sterilized and unsterilized sorghum under various treatment conditions. Forage fiber analysis showed that cell wall structure was modified, and hemicellulose and cellulose amounts were reduced by both inoculation with Clostridium cellulolyticum and physical treatment effects. More cellobiose was produced from sterilized sorghum treated with C.cellulolyticum than the other treatments. |
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| Item Description: | "Major subject: Agricultural engineering." Typescript (photocopy). Vita. |
| Physical Description: | xi, 121 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |