Selective medium for leuconostoc detection.

The production of slime by microorganisms in the sugar cane juice of sugar mills has been primarily attributed to Leuconostoc mesenteroides (McCleskey, Faville, and Barnett, J. Bacteriol., 54, 697, 1947). In a study of the epiphytic microflora of sugar cane, Mayeux and Colmer (Sugar J., 23, 28, 1960) reported the presence of many organisms on the growing plant but failed to show the presence of leuconostoc. However, they found leuconostoc present on the harvested cane that was ready for grinding. A study was In early attempts to make sucrose agar more selective, we used either potassium cyanide or crystal violet alone or in combination with sodium azide, in concentrations from 0.01 to 0.05% of each agent. These were not entirely successful as they either failed to inhibit the undesired organisms or inhibited leuconostoc. A lower concentration of sodium azide used alone was successful. The basal medium was dispensed to give 100-ml amounts, sterilized at 121 C for 15 min, and just prior to use 0.5 ml of