Effect of protein hydrolysates on the growth of species of the genus Enterococcus

Abstract

Microorganisms have different and specific nutritional requirements. Enterococci are a group of nutritionally fastidious bacteria in their metabolic processes. For the isolation of these microorganism’s different combinations of protein hydrolysates must be used in defined proportions capable of supplying their metabolic needs. The aim of this work was to study the effect of protein hydrolysates from different origin on the growth of enterococci. Three nutritional compositions were tested in which protein hydrolysates from different animal and microbial origin were included (bacteriological peptone Z, meat extract and tryptose). Nutritional compositions were evaluated using microorganisms from the Genus Enterococcus and from other microbial genera, by different microbiological methods. Tryptose, developed in BioCen, proved to be highly nutritive components for the development of enterococcal colonies with diameters larger than 2 mm after incubation for 24 hours. Enterococci showed pink color and most of microorganisms belonging to other genera were inhibited by the action of thallium acetate. The mixture of tryptose and meat extract, at the concentrations of 5,0 and 3,0 g/L, respectively, assured favorable nutritional conditions and the fast development of different species of enterococci of diabetes.