High-yield Production of Alpha-galactosidase Excreted from Penicillium Chrysogenum and Aspergillus Niger

α-Galactosidase production by the fungal strains Penicillium chrysogenum LN33 and Aspergillus niger M47 cultivated in shaking and stationary conditions using soya meal extract as nutrient medium was investigated. Submerged shake flask fermentation was preferred over stationary cultivation for P. chrysogenum LN33 as it gave a high α-galactosidase yield (4200U/l). Because of pellet formation the semicontinuous shake-flask fermentation was carried out for P. chrysogenum LN33 α-galactosidase production during 32 days. The maximum α-galactosidase activity by A. niger M47 (7000U/l) was obtained in stationary conditions of cultivation which is 27-28% greater as compared with the enzyme titer in shaking cultures. Air-lift laboratory bioreactor cultivation of both P. chrysogenum LN33 and A. niger M47 resulted in high-yield production of α-galactosidase (8700U/l and 11200U/l, respectively), which is of particular interest for biotechnological application in food processing.