Bioprocessing – Including Separations
DuPont, Wilmington, DE
Baylor University, Waco, TX
The bioprocessing session of the 26
Symposium attracted a large
number of submissions, with over 70 oral and poster presentations. This
magnitude of work reflected a tremendous variety in approaches and
issues being addressed for the processing of biomass and related separa-
Feedstocks of all kinds are being investigated, with many studies
looking at large volume agricultural sources such as corn stover and
bagasse and others targeting specific waste streams, such cheese whey, cull
potatoes or dairy manure. Active research is also being carried out on vari-
ous forms of bioremediation of toxic wastes, both organic and inorganic.
Most studies using cellulosic resources pretreated the feedstock, with com-
mon methods appearing to be dilute acid hydrolysis, steam explosion and
alkaline treatments. Utilization of gas phase substrates is also being widely
studied in various contexts.
Products being investigated offered even more variety that the feed-
stocks utilized. Ethanol remains the dominant focus of wide attention,
however there appears to be increasing interest in other commodity scale
products such as organic acids, longer chain alcohols and xylitol. Organic
acids to be used as chemical feedstocks for further conversions are appar-
ently gaining prominence. More specialized bioproducts such as surfactin,
biocides or microbial polysaccharides are also receiving attention.
Processing and separations technologies also indicate a tremendous
amount of creative energy being applied to the issues of bioprocessing.
Extractive and separatory fermentation systems received much attention,
with many techniques investigated, including two-phase fermentations,
membrane extraction methods, ion exchange, dialysis and foam fractiona-
tion. Extraction processes were largely motivated by the need for either
inexpensive product purification or for reducing the inhibitory products
resulting from pretreatment and fermentation. Indeed, several studies
were concerned specifically with reducing the inhibition resulting from
biomass pretreatment processes. Immobilization was a common practice
for both cells and enzymes. Lastly, modeling appears to be a common and
Applied Biochemistry and Biotechnology
Vol. 121–124, 2005
Copyright © 2005 by Humana Press Inc.
All rights of any nature whatsoever reserved.
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