THE COMPARISON OF THE BRILA-MUG AND LAURY L SULFATE-MUG BROTHS AS MEDIA FOR THE ENUMERATION OF TOTAL AND FECAL-COLIFORM BACTERIA IN BATHINGWATERS ACCORDING TO THE EC-GUIDELINE 76 160 EWG/

The spectrum of gramnegative rods occurring in surface waters is wide and depending on the season, i.e. the water temperature. The concentra tion of bacteria is higher in summer than in winter. However, the seas onal difference of the concentration of Enterobacteriaceae is less tha n that of the Aeromonas spec. and of the non-fermenters. The compariso n of yields of total and faecal coliforms determined in samples of sur face water by using the brilliant green bile lactose 4-methylumbellife ryl-beta-D-glucuronide (BRILA-MUG) broth and the lauryl sulfate-MUG br oth, respectively, shows that the BRILA-MUG) broth is more sensitive a nd gives higher yields than the lauryl sulfate-MUG broth. On the other hand, the lauryl sulfate-MUG broth inhibits more the growth of gramne gative rods, especially that of Aeromonas spec. and non-fermenters, wh ereas the Enterobacteriaceae are less inhibited.