Five strains of Kluyveromyces marxianus a one of Gandida pseudotropicalis were cultured in medium M· 1 for productión of β-galactosidase (E.C: 3:2:1:23). The strain Kluyveromyces marxianus NRRL- Y - 1109 was selecteed for the best production (11.6 U/ml). The maximum yield of enzyme (1330 U ONPG/g of biomass) was obtained on 5% of lactose supplemented with 0.5% yeast extract , 0.75% (NH4)2SO4 y 0.45% K2HPO4 (W/V). The best extraction of the enzyme from viable cells was performed by toluene 2% (v/v), at pH 7.0 ± 0.1, 30ºC during 15 hours of treatment, in 0.1 M potassium phosphate buffer, supplemented with 1 mM magnesium and 0.1 mM manganese sulfate. The enzyme was partially purified with acetone. lt obtained a specific activity of de 73 U LACTOSA/mg of protein and a yield of 93.3%. Optimun pH and temperature for enzyme activity were pH 6.6 and 40°C. The Km for lactose was 15 mM and V...

Five strains of Kluyveromyces marxianus a one of Gandida pseudotropicalis were cultured in medium M· 1 for productión of β-galactosidase (E.C: 3:2:1:23). The strain Kluyveromyces marxianus NRRL- Y - 1109 was selecteed for the best production (11.6 U/ml). The maximum yield of enzyme (1330 U ONPG/g of biomass) was obtained on 5% of lactose supplemented with 0.5% yeast extract , 0.75% (NH4)2SO4 y 0.45% K2HPO4 (W/V). The best extraction of the enzyme from viable cells was performed by toluene 2% (v/v), at pH 7.0 ± 0.1, 30ºC during 15 hours of treatment, in 0.1 M potassium phosphate buffer, supplemented with 1 mM magnesium and 0.1 mM manganese sulfate. The enzyme was partially purified with acetone. lt obtained a specific activity of de 73 U LACTOSA/mg of protein and a yield of 93.3%. Optimun pH and temperature for enzyme activity were pH 6.6 and 40°C. The Km for lactose was 15 mM and V...

Five strains of Kluyveromyces marxianus a one of Gandida pseudotropicalis were cultured in medium M-1 for productión of 13- galactosidasa (E.C : 3:2:1:23). The strain Kluyveromyces mandanus NRRL- Y - 1109 was selecteed for the best production of enzyme and the maxímum yield of enzyme was obtaíned on 5% of lactose supplemented with 0.5% yeast extract , 0.75% (NH4)2 S04 y 0.45% K2HP04 (w/v). lt obtained a yield of 5.43 U/mg of protein and 1.31 A.UoNPcl mg of dry weight. The extraction of the enzyme from viable cells was performed by toluene 2% (v/v), during 15 hours of treatment at 30°C, in 0.1 M potassium phosphate buffer, pH 7.0 ± 0.1, supplemented with 1 mM magnesium and 0.1 mM manganese sulfate . The yield of immobilization of enzyme on chitin treated with glutaraldehide was 41%, being the optimum pH of 6.6 ± 0.1. The values of Km and Vm for immobilized using lactase as substrate...

Five strains of Kluyveromyces marxianus a one of Gandida pseudotropicalis were cultured in medium M-1 for productión of 13- galactosidasa (E.C : 3:2:1:23). The strain Kluyveromyces mandanus NRRL- Y - 1109 was selecteed for the best production of enzyme and the maxímum yield of enzyme was obtaíned on 5% of lactose supplemented with 0.5% yeast extract , 0.75% (NH4)2 S04 y 0.45% K2HP04 (w/v). lt obtained a yield of 5.43 U/mg of protein and 1.31 A.UoNPcl mg of dry weight. The extraction of the enzyme from viable cells was performed by toluene 2% (v/v), during 15 hours of treatment at 30°C, in 0.1 M potassium phosphate buffer, pH 7.0 ± 0.1, supplemented with 1 mM magnesium and 0.1 mM manganese sulfate . The yield of immobilization of enzyme on chitin treated with glutaraldehide was 41%, being the optimum pH of 6.6 ± 0.1. The values of Km and Vm for immobilized using lactase as substrate...