Production of B-glucosidase using immobilised Piromyces sp. KSX1 and Orpinomyces sp. 478P1 in repeat-batch culture

Abstract

Two anaerobic fungi, one a monocentric strain (Piromyces sp. KSX1) and the other a polycentric strain (Orpinomyces sp. 478P1), were immoblised in calcium alginate beads and cultured in sequential batches where spent medium (containing o.25% cellobiose) was repeatedly drained and replaced. B-Glucisudase production with KSX1 was maintained for 45 days over six repeated batch cultures yielding a maximum level of 107 mIU/ml. For 478P1, B-glucosidase production was maintained for 30 days over four repeated batches yielding a maximum level of 34 mIU/ml. Although repeat-batch cultures of KSX1 produced more B-glucosidase than strain 478P1, the maximum specific B-glucosidase produced from these immobilised cultures was similar. the immobilised polycentric strain proved to be operationally superior to strain KSX1, as strain 478P1 did not produce any growth in the culture liquor.