Efficient and simple extraction of mouldy bran in a pulsed column extractor for recovery of amyloglucosidase in concentrated form

The recovery of amyloglucosidase from mouldy bran obtained from a solid-state fermentation system in a pulsed plug flow extractor was 86% with the use of 10 ml min-1 feed rate of the solvent and 87 min extraction time. The resulting extract volume was twice that of the weight of dry mouldy bran. An increase in the extraction time at the same feed rate resulted in improved extraction efficiencies, but the resulting extract was too dilute in nature. The use of a submerged column extractor for preventing possible channelling, together with the addition of calcium acetate to the feed solvent to reduce the viscosity of the extract, resulted in lower recoveries. The data indicate practical and economic advantages of pulsed plug flow extractors over the currently used percolation and multiple-contact counter-current leaching techniques.