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Tachea, Firehiwot

Publications and source records attributed to Tachea, Firehiwot.

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Simultaneous application of predictive model and least cost formulation can substantially benefit biorefineries outside Corn Belt in United States: A case study in Florida

Previously, a predictive model was developed to identify optimal blends of expensive high-quality and cheaper low-quality feedstocks for a given geographical location that can deliver high sugar yields. Here, the optimal process conditions were tested for application at commercially-relevant higher biomass loadings. We observed lower sugar yields but 100% conversion to ethanol from a blend that contained only 20% high-quality feedstock. The impact of applying this predictive model simultaneously with least cost formulation model for a biorefinery location outside of the US Corn Belt in Lee County, Florida was investigated. A blend ratio of 0.30 EC, 0.45 SG, and 0.25 CS in Lee County was necessary to produce sugars at high yields and ethanol at a capacity of 50 MMGY. This work demonstrates utility in applying predictive model and LCF to reduce feedstock costs and supply chain risks while optimizing for product yields.

09 BIOMASS FUELS↗
DOE OSTI2017

A bacterial pioneer produces cellulase complexes that persist through community succession

Cultivation of microbial consortia provides low-complexity communities that can serve as tractable models to understand community dynamics. Time-resolved metagenomics demonstrated that an aerobic cellulolytic consortium cultivated from compost exhibited community dynamics consistent with the definition of an endogenous heterotrophic succession. The genome of the proposed pioneer population, 'Candidatus Reconcilibacillus cellulovorans', possessed a gene cluster containing multidomain glycoside hydrolases (GHs). Purification of the soluble cellulase activity from a 300litre cultivation of this consortium revealed that ~70% of the activity arose from the 'Ca. Reconcilibacillus cellulovorans' multidomain GHs assembled into cellulase complexes through glycosylation. These remarkably stable complexes have supramolecular structures for enzymatic cellulose hydrolysis that are distinct from cellulosomes. The persistence of these complexes during cultivation indicates that they may be active through multiple cultivations of this consortium and act as public goods that sustain the community. Thus, the provision of extracellular GHs as public goods may influence microbial community dynamics in native biomass-deconstructing communities relevant to agriculture, human health and biotechnology.

09 BIOMASS FUELS↗
DOE OSTI2017

High Performance Polymers from Biomass

The objective of this study was to demonstrate feasibility and scale-up of cellulosic feedstocks for the production of a commercial C6 lactone. Visolis, Inc. has developed a fermentation platform for production of the lactone at high titers and yields. The lactone is used in high-end cosmetics industry and also serves as a valuable intermediate for production of biopolymers and biofuels. Strains employed by Visolis are capable of metabolizing both glucose and xylose, enabling full utilization of cellulosic hydrolysates as feedstock. Visolis and ABPDU conducted a 2L proof-of-concept fermentation campaign followed by a 50L scale-up campaign.

09 BIOMASS FUELS↗
DOE OSTI2017

Production of the gasoline additive 3-methylanisole via fermentation of cellulosic sugars. (CRADA Final Report)

Researchers at Rho Renewables and the Advanced Biofuels Process Demonstration Unit at Lawrence Berkeley National Lab have successfully demonstrated a system for biological production of m-cresol and 3-methylanisole. Both molecules are valuable commodity chemicals; 3-methylanisole has favorable properties as a fuel additive while m-cresol is widely used as a flavor and vitamin intermediate. Recovery of volatile 3-methylanisole from fermenter off-gas was documented using both in situ extractive fermentation and ex situ solvent traps. This work demonstrates the feasibility of m-cresol and 3-methylanisole production under industrially relevant conditions and helps pave the way for larger scale production.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Novel Biocatalytic Platform for Ethanol Production from Lignocellulosic Feedstock

The goals of the CRADA were achieved by illustrating the scalability of immobilized yeast technology, demonstrating lignocellulosic feedstock consumption by the immobilized cells, and confirming Microvi’s proprietary polymer matrix ethanol toxicity tolerance. We conducted fermentations at 2L and 300L scales. For carbon source, we performed pretreatment and saccharification at 100L scale to produce lignocellulosic sugars with glucose and xylose.

09 BIOMASS FUELS↗