The world in the 21st century is facing a dual crisis of increasing waste and global climate change. Substituting fossil fuels with waste biomass-derived cellulosic ethanol is a promising strategy to simultaneously meet part of our energy needs, mitigate greenhouse gas (GHG) emissions, and manage municipal solid waste (MSW). However, the global potential of MSW as an energy source is as yet unq...

The carboxymethyl-cellulase and Avicelase activities of Thermoactinomyces sp., strain YX, were produced simultaneously with cell growth. Throughout the growth phase these activities were primarily extracellular, with up to 50% adsorbed to residual cellulosic substrate at any one time. On the other hand, the beta-glucosidase activity was associated with the culture solids throughout the entire f...

Understanding the interactions between cellulases and cellulosic substrates is critical to the development of an efficient artificial cellulase system for conversion of biomass to sugars. We directed specific mutations to the interactive surface of the Acidothermus cellulolyticus EI endoglucanase catalytic domain. The cellulose-binding domain is not translated in these mutants. Amino acid mutat...

Enzymatic hydrolysis of cellulose is key for the production of second generation biofuels, which represent a long-standing leading area in the field of sustainable energy. Despite the wealth of knowledge about cellulase structure and function, the elusive mechanism by which these enzymes disintegrate the complex structure of their insoluble substrate, which is the gist of cellulose saccharifica...

A kinetic model of cellulosic biomass conversion to ethanol via simultaneous saccharification and fermentation (SSF) developed previously was validated experimentally using paper sludge as the substrate. Adsorption parameters were evaluated based on the data obtained at various values for fractional cellulose conversion. The adsorption model was then combined with batch SSF data to evaluate the...

One of the important targets is to unlock the full potential of cellulosic biomass. Plants have evolved over several hundred million years to be recalcitrant—resistant to attacks from the likes of bacteria, fungi, insects, and extreme weather. Breaking down plants is no easy task. For cellulosic ethanol production, the primary challenge is breaking down (hydrolyzing) cellulose into its componen...

To test the hypothesis that microbial communities from saline and thermal sediment environments are pre-adapted to exhibit superior fermentation performances, 501 saline and thermal samples were collected from a wide geographic range. Each sediment sample was screened as inoculum in a 30-day batch fermentation. Using multivariate statistics, the capacity of each community was assessed to determ...

The development of biorefineries to produce fuel ethanol and commodity chemicals from lignocellulosic biomass is a potential alternative to current reliance on non-renewable resources. However, many technological barriers remain despite research progress in the past several decades. This article examines the major process barriers in biochemical conversion of biomass to cellulosic ethanol. We r...

The chimeric proteins viz. CBM3-Cel9A, CBM4-Cel9A and CBM30-Cel9A, are constructed by fusion of family 3, 4, and 30 cellulose binding modules (CBMs) to N-terminus of family 9 endoglucanase (Cel9A) from Alicyclobacillus acidocaldrious. The chimeric enzymes were successfully expressed in Escherichia coli and purified to homogeneity. The chimeric enzymes showed significant increase in Avicel (8-12...

Abstract There is increasing attention to the production of cellulose nanocrystals (CNCs) from lignocellulosic biomass by enzymatic hydrolysis with cellulase. In this study, feasibility application a cellulase system engineered strain Penicillium oxalicum cEES in CNCs was assessed. Using commercial eucalyptus dissolving pulp (EDP) as substrate, were successfully obtained cEES, and total yields ...