Research overview
Prof. Viljoen-Bloom’s research programme focuses on the biological processing of plant material to add value to various agricultural products. In collaboration with prof. Emile van Zyl, microbial enzymes are evaluated for the hydrolysis of local feedstocks for the production of bio-ethanol. Her group, supported by Dr. Shaunita Rose, investigates the hydrolysis of starch by means of genetically modified amylolytic yeast strains. Starch is one of the most abundant organic polysaccharides available for the production of bio-ethanol as an alternative transport fuel. Cost-effective utilisation of starch requires consolidated bioprocessing (CBP) where a single microorganism can produce the enzymes required for hydrolysis of starch, and also convert the glucose monomers to ethanol. The yeast Saccharomyces cerevisiae is known for its high fermentative capacity, high ethanol yield and high ethanol tolerance, but it is incapable of hydrolysing starch or dextrins. Genetic engineering can be used for the construction of recombinant S. cerevisiae strains expressing amlylolytic enzymes to allow these strains to hydrolyse raw starch for the production of bio-ethanol.
Main projects
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Recombinant expression of different alpha- and gluco-amylases to identify the best combination for optimal hydrolysis of raw starch
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Evaluate the impact of different secretion signals on the recombinant expression of gluco-amylases
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Evaluate expression of α-amylases under the control of different promoters in
S. cerevisiae
