RESUMEN
Factors affecting the beta-galactosidase production by Penicillium notatum 1 were studied using fermentation media of different chemical composition. The medium containing lactose, salts, peptone and yeast extract with initial pH 2.5 was selected as the best for enzyme production. Monobasic ammonium phosphate (0.9%) was found to be the best inorganic nitrogen source for lactase production. Various extraction media and metabolic inhibitors were examined for effective releasing of beta-galactosidase from the fungal cells. Using a simple method of mycelium extraction with 0.1 Triton X-100, it was possible to obtain about 4-fold higher amounts of enzyme in the cell free extracts, than those excreted into the post-culture liquid.
Asunto(s)
Penicillium/enzimología , beta-Galactosidasa/biosíntesis , Medios de Cultivo , Penicillium/crecimiento & desarrolloRESUMEN
Spherical, osmotically fragile protoplasts were obtained from the mycelium of Penicillium paxilli. The lytic enzymes were derived from the culture filtrate of P. purpurogenum grown on disintegrated mycelium of P. paxilli. Maximum numbers of protoplasts were released from 36 h mycelium, using 1 M sorbitol as an osmotic stabilizer, at pH 5.8, after 2 h incubation with lytic enzymes at 30 degrees C.