Enzyme production in continuous cultivation by the thermophilic fungus, Thermomyces lanuginosus

Abstract

The production of extracellular enzymes by the thermophilic fungus Thermomyces lanuginosus was studied in chemostat cultures at a dilution rate of 0.08 h⁻¹ in relation to variation in the ammonium concentration in the feed medium. Under steady state conditions, three growth regimes were recognised and the production of several extracellular enzymes from T. lanuginosus was recorded under different nutrient limitations ranging from nitrogen limitation to carbon/energy limitation. The range and the production of carbohydrate hydrolysing enzymes and lipase increased from Regime I (NH₄Cl ≤ 600 mg l⁻¹) to Regime III (NH₄CI ≥ 1200 mg l⁻¹), whereas production of protease was highest in Regime II (600 mg l⁻¹ < NH₄Cl <1200 mg l⁻¹).