Detection of esterolytic activity of lactobacilli isolated from goat´s and ewe´s milk and cheeses

ABEIJÓN, M.C.; MEDINA, R.B. ; GONZÁLEZ, S.N.

Tafí del Valle, Tucumán

Jornada; XXII Jornadas Científicas de la Asociación de Biología de Tucumán; 2005

Asociación de Biología de Tucumán

Esterases are enzymes that hydrolise esters of short chain fatty acids (C2-C10), producing piquant flavours and intense aromas. Esterases of lactic acid bacteria are also involved in the development of fruity flavours. The aim of this work was to evaluate the intracellular esterolytic activity of Lactobacillus strains isolated from goat´s and ewe´s milk and cheese. Post-electrophoretic detection of esterase activity showed the presence of 1 to 3 bands per strain. The most intense bands were detected on a-naphtylacetate. Caprine strains presented higher activity on a-naphtylbutyrate (0.57-4.93 U/mg). Significant activities were also detected on a-naphtylcaproate (1.14-4.68 U/mg) and a-naphtylcaprate (1.40-4.20 U/mg). In ovine strains, esterolytic activity was only detected on a-naphtylacetate. No hydrolysis of a-naphtylaurate was observed. The strains studied in this work released short chain fatty acids and therefore, they would actively contribute to the development of milk and cheese  flavour.