Influence of medium composition on esterase activity from Bacillus strain

LOTO, FLAVIA; BAIGORI, MARIO DOMINGO; PERA, LICIA MARÍA

Tafi del Valle, Tucumán, Argentina.

Jornada; XXII Annual Scientific Meeting. Tucumán Biology Society; 2006

Tucumán Biology Society

INFLUENCE OF MEDIUM COMPOSITION ON ESTERASE ACTIVITY FROM BACILLUS STRAINS Loto F, Baigorí M and Pera L PROIMI Av. Belgrano y Pje. Caseros, 4000 Tucumán. Tel: 4344888, e-mail: lpera@hotmail.com Introduction. Carboxylesterases (EC 3.1.1.1) can catalyses ester synthesis and transesterification. They have been widely used in industrial application such as in food, chemical and pharmaceutical industries. Selective conversions of natural or synthetic substrates into useful products using whole cells or isolated enzymes have been gaining an increasing importance among the methods for the production of organic substances. Objective. Evaluation of the influence of medium composition on both free and biomass-bound esterase activity. Materials and methods. Free and biomass-bound esterase activities were studied with Bacillus sp. A60 and Bacillus subtilis 168, respectively. Esterase activity was determined by using p-nitrophenylacetate as substrate. Microorganisms were grown at 37°C using a set of modified Luria-Bertani media (LB). Results and conclusions. When 12.5 g/l tripteine was added the extracellular esterase specific activity was improved. Interesting, when either tripteina or yeast extract were not added significant increased specific biomass-bound esterase activity were observed. This work was supported by grant CABBIO 2000 cod 012