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This chapter describes two simple interrelated non-chromatographic methods of protein purification. In the first method, called affinity precipitation, inherent affinity of reversibly soluble–insoluble polymers (also called stimuli-sensitive or smart polymers) is exploited to form an affinity complex in free solution with target protein. The affinity complex is precipitated by a suitable change in the medium. The desired protein is dissociated from the smart polymer. In the second method called macro (affinity ligand)-facilitated three phase partitioning (MLFTPP), the affinity complex is precipitated at an interface between upper t-butanol-rich phase and lower aqueous phase. These three phases are achieved by adding appropriate amounts of ammonium sulfate and t-butanol to the initial crude extract. In the first protocol, sequential MLFTPP is used with two different smart polymers to purify pectinase and cellulase from a single crude preparation. The second protocol illustrates the application of the affinity precipitation in simultaneous purification and refolding of a urea-denatured xylanase. [ABSTRACT FROM AUTHOR]

An approach is presented for obtaining relative filter paper activities for enzyme preparations having activities below that required for application of the traditional International Union of Pure and Applied Chemistry filter paper assay. The approach involves the utilization of protein stabilizers to retard the time-dependent enzyme inactivation that may occur under traditional filter paper assay conditions. Enzyme stabilization allows extended reaction times and the calculation of relative activities based on the time required for saccharification of 3.6% of the traditional substrate, making results proportional to those obtained in the traditional International Union of Pure and Applied Chemistry assay. The assay is demonstrated using a commercial cellulase preparation along with KCl and bovine serum albumin as protein stabilizers. [ABSTRACT FROM AUTHOR]

The multinucleate conidia were produced from the green mature conidia of Trichoderma reesei Rut C-30 strain by colchicine treatment. The strain with higher Filter paper degrading ability was selected among those conidia using a double layer selection medium. The selected strain, JS-2 was able to collapse the filter paper within 15 min but the original strain took 25 min to collapse it completely. Moreover, the amount of reducing sugar in the L-type glass tube of the strain, JS-2, was greater than that of the original strain. The Avicel, CMC-Na, and Salicin hydrolyzing activity of the strain, JS-2, increased 2.1 times, 1.2 times, and 3.6 times higher than that of the original strain. [ABSTRACT FROM AUTHOR]

Ensilage can be used to store lignocellulosic biomass before industrial bioprocessing. This study investigated the impacts of seven commerical enzyme mixtures derived from Aspergillus niger, Trichoderma reesei, and T. longibrachiatum. Treatments included three size grades of corn stover, two enzyme levels (1.67 and 5 IU/g dry matter based on hemicellulase), and various ratios of cellulase to hemicellulase (C : H). The highest C : H ratio tested, 2.38, derived from T. reesei, resulted in the most effective fermentation, with lactic acid as the dominant product. Enzymatic activity during storage may complement industrial pretreatment; creating synergies that could reduce total bioconversion costs. [ABSTRACT FROM AUTHOR]

The development of bioconversion technologies for production of fuels, chemicals, and power from renewable resources is currently a high priority for developed nations such as the United States, Canada, and the European Union as a way to improve national energy security and reduce greenhouse gas emissions. The widespread implementation of such technologies will require a sustainable supply of biomass from forestry and agriculture. Forests are a major source of feedstocks for biofuels production in Canada. Woody biomass includes residues from logging and forest thinning, and from wood processing and pulp production. More recently, damaged wood caused by beetle infestations has become available on a large scale in Western Canada. This study evaluates beetlekilled British Columbian hybrid spruce (HS) (Picea glauca × P. engelmannii) as a feedstock for the production of bioethanol. In the past 30 yr, attack by the beetle Dendroctonus rufipennis and associated fungi has resulted in estimated losses of more than three billion board feet in British Columbia alone. Here we describe the chemical and some physical characteristics of both healthy (HHS) and beetle-killed (BKHS) British Columbian HS and evaluate the technical feasibility of using these feedstocks as a source of biomass for bioethanol production. Untreated HHS and BKHS did not differ significantly in chemical composition except for the moisture content, which was significantly lower in BKHS (approx 10%) compared with HHS (approx 18%). However, the yields of carbohydrates in hydrolyzable and fermentable forms were higher at mild pretreatment conditions (H-Factor <1000) for BKHS compared with HHS. At medium (H-Factor 1000–2000) and severe (H-Factor >2000) pretreatment conditions HHS and BKHS behaved similarly. Organosolv pretreated HHS and BKHS demonstrated good ethanol theoretical yields, approx 70 and 80%, respectively. [ABSTRACT FROM AUTHOR]

An abstract of the article "Cellulose Metabolism in plants," by Takahisa Hayashi and colleagues is presented.