Purple Agar base (Difco Manual) was prepared and 0.5% glucose
or glycerolwas added. Themediawas autoclaved for 15 min. Glycerol
mediawas poured into petri dishes and glucose mediawas placed in
5 ml tubes. For testing, bacteria were streaked from Nutrient agar
after 24 h of growth on to glycerol plates and incubated at 37 C for up to 72 h. Plates were examined every 24 h for acid production.
Glucose tubes were inoculated from Nutrient agar after 24 h of
growth and the media covered with sterile mineral oil. The tubes
were incubated at 37 C for up to 72 h. Tubeswere examined for acid
production every 24 h. Previous testing revealed three Micrococcus
strains to have weak positive fermentation patterns (glycerol one;
glucose 2 others). This finding was confirmed for two of the strains
(ASO3-C10 and ASO3-C17); both were weakly positive for glucose
metabolism, which is inconsistent with their being M. luteus.
However, this was not confirmed for the other strain (AS03-C6) and
does illustrate the subjectivity of reading color reactions.