Optimisation of enzymatic hydrolysis of apple pomace for production of biofuel and biorefinery chemicals using commercial enzymes.
Apple pomace, a waste product from the apple juice industry is a potential feedstock for biofuel and biorefinery chemical production. Optimisation of hydrolysis conditions for apple pomace hydrolysis using Viscozyme L and Celluclast 1.5L was investigated using 1 L reaction volumes. The effects of temperature, pH, β-glucosidase supplementation and substrate feeding regimes were determined. Hydrolysis at room temperature using an unbuffered system gave optimal performance. Reactors in batch mode resulted in a better performance (4.2 g/L glucose and 16.8 g/L reducing sugar, 75 % yield for both) than fed-batch (3.2 g/L glucose and 14.6 g/L reducing sugar, 65.5 and 73.1 % yield respectively) in 72 h. The addition of Novozyme 188 to the core mixture of Viscozyme L and Celluclast 1.5L resulted in the doubling of glucose released. The main products (yield %) released from apple pomace hydrolysis were galacturonic acid (78 %), glucose (75 %), arabinose (90 %) and galactose (87 %). These products are potential raw materials for biofuel and biorefinery chemical production.
Department of Biochemistry and Microbiology, Rhodes University, PO Box 94, Grahamstown, 6140, South Africa.
Repson
R
Gama
Department of Biochemistry and Microbiology, Rhodes University, PO Box 94, Grahamstown, 6140, South Africa.|Forest Products Biotechnology Group, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
J Susan
JS
Van Dyk
Department of Biochemistry and Microbiology, Rhodes University, PO Box 94, Grahamstown, 6140, South Africa. b.pletschke@ru.ac.za.
Brett I
BI
Pletschke
Apple pomace; Celluclast; Inhibition; Lignocellulose; Viscozyme