초록
Lipases were produced by a microbial consortium derived from a mixture of wastewater sludges in a medium containing solid industrial wastes rich in fats, under thermophilic conditions (temperature higher than 45<SUP>o</SUP>C for 20days) in 4.5-L reactors. The lipases were extracted from the solid medium using 100mM Tris-HCl, pH 8.0 and a cationic surfactant agent (cetyltrimethylammonium chloride). Different doses of surfactant and buffer were tested according to a full factorial experimental design. The extracted lipases were most active at 61-65<SUP>o</SUP>C and at pH 7.7-9. For the solid samples, the lipolytic activity reached up to 120,000UA/g of dry matter. These values are considerably higher than those previously reported in literature for solid-state fermentation and highlight the possibility to work with the solid wastes as effective biocatalysts.