Acid protease recovery from a solid-state fermentation system

H.M. FERNÁNDEZ LAHORE; E.R. FRAILE; O. CASCONE

JOURNAL OF BIOTECHNOLOGY

ELSEVIER SCIENCE BV

Año: 1998 vol. 62 p. 83 - 93

0168-1656

lnvestigations have been carried oLrt on an acid protease produced by Mucor bacilli/ormis under solid-state fermentation conditions as a model of recovery and purification of a protein from a solid culture medium. The leaching efficiency of sodium chloride solutions to recover the enzyme from the fermented mass was higher than that of non-ionic detergents (Triton X-100 or Tween 80) or distilled water. Concentration and coarse fractionation of the crude extract could be achieved with a high yield of protease by precipitation with ethanol or acetone and by ultrafiltration and diafiltration in the presence of NaCl. Diafiltration was selected for the prechromatographic treatment of the crude extract as it enhances the maximum fraction of enzyme bound to an anion-exchanger up to 0.9. An overall purification factor of 15.5 rvas reached, with a total enzyme recovery of 46t,/0, with the purification procedure developed by using this methodology. The final product obtained was a highly purified food-grade protease preparation.