High-solids enrichment of thermophilic microbial communities and their enzymes on bioenergy feedstocks [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 662.8 Other fuels
• Thông tin xuất bản: Berkeley, Calif. : Oak Ridge, Tenn. : Lawrence Berkeley National Laboratory ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2011
• Mô tả vật lý: Medium: ED : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 265502
• Chủ đề: 1. 09 biomass fuels; 2. 54 environmental sciences; 3. 58 geosciences; 4. Agricultural wastes; 5. Cellulose

Tóm tắt

 Thermophilic microbial communities that are active in a high-solids environment offer great potential for the discovery of industrially relevant enzymes that efficiently deconstruct bioenergy feedstocks. In this study, finished green waste compost was used as an inoculum source to enrich microbial communities and associated enzymes that hydrolyze cellulose and hemicellulose during thermophilic high-solids fermentation of the bioenergy feedstocks switchgrass and corn stover. Methods involving the disruption of enzyme and plant cell wall polysaccharide interactions were developed to recover xylanase and endoglucanase activity from deconstructed solids. Xylanase and endoglucanase activity increased by more than a factor of 5, upon four successive enrichments on switchgrass. Overall, the changes for switchgrass were more pronounced than for corn stover
  solids reduction between the first and second enrichments increased by a factor of four for switchgrass while solids reduction remained relatively constant for corn stover. Amplicon pyrosequencing analysis of small-subunit ribosomal RNA genes recovered from enriched samples indicated rapid changes in the microbial communities between the first and second enrichment with the simplified communities achieved by the third enrichment. The results demonstrate a successful approach for enrichment of unique microbial communities and enzymes active in a thermophilic high-solids environment.