A recombinant esterase from Lactobacillus plantarum was immobilized on hydrophobic support polypropylene Accurel MP1000 by adsorption. Adsorption efficiency was 83%, and the immobilized protein was 12.4 mg/g of support. Esterase activity was determined using p-nitrophenyl butyrate as substrate, and highest activities were observed at 50 A degrees C for immobilized enzyme and 30 A degrees C for free enzyme extract. Concerning thermal stability, after enzyme incubation at 80 A degrees C for 30 min, immobilized and free enzyme retained 91% and 56% of initial activity, respectively. Immobilized enzyme presented lower V (max) and higher K (m) than free enzyme. Protein was not released from the support, and esterase activity increased after 3 cycles of reuse.