We studied 630 bacterial strains isolated from surface waters and determine
d as enterococci on the basis of their growth on Slanetz-Bartley agar in ty
pical colonies. The strains were tested and characterized by several key co
nventional tests for basic differentiation of enterococci and by commercial
test kits. We identified 135 strains of E. foecium (21 %), 115 E. foecalis
(18 %), 30 E. mundtii (5 %), 27 E. hirae (4 %), 22 E. casseliflavus (3 %),
21 E. gallinarum (3 %), 17 E. durans-E. hirae complex (3 %), 5 E. durans (
1 %), and 1 strain of E. avium. 150 strains were classified only as Enteroc
occus sp. (25 %) and 107 strains (17 %) isolated from Slanetz-Bartley agar
were not enterococci. We found that the non-enterococcal group consisted of
other Gram-positive cocci and Gram-positive and Gram-negative rods. Based
on the identification we tried to find a relation between taxonomic positio
n of isolated strains and their colony morphology on Slanetz-Bartley agar.
Out of the total of 523 identified enterococci, 345 strains (66 %) formed p
urple colonies, 136 red colonies (26 %), 37 pink colonies (7 %) and 5 cream
colored colonies (1%). There was no correlation among the color, size or c
olony morphology and the taxonomic characterization of enterococcal strains
.