A Study of Milk Coagulation as a Differential Feature of Monilia albicans and Monilia Candida.

Abstract

Though Monilia albicans and Monilia Candida have so far been shown to give the same serological reactions, 1 nevertheless in disagreement with Stone and Garrod's conclusion, 2 we consider 3 , 4 , 5 , 6 that there are sufficient cultural, biochemical, and pathogenic differences to justify placing the organisms in 2 different species. A prominent difference is the coagulation of milk by M. albicans in striking contrast to M. candida's inability. The purpose of this study was to determine the conditions under which coagulation occurred and to see if in all cases a constant, definite difference in the species was observable. In addition, another objective was to demonstrate that the rennet-like coagulation of the albicans type is probably distinct from the adherent mat or mycelial pad formation of M. candida which produces a pseudo-coagulative effect.

In the work with coagulation the procedure for the preparation of the calcium-lactate milk medium is that formerly described. 3

While it was found that coagulation could readily be accomplished through the use of any of the M. albicans cultures themselves yet the utilization of an extract from that species would permit a better comparison of clotting results with commercial rennin. Now in order to perform experiments with extracting agents it was necessary to obtain a heavy cell yield, and for this purpose large Blake bottles containing Trommer's malt-extract agar were used. After several extracting agents had been employed without marked success, sterile distilled water in 20 to 25 cc. portions per Blake bottle was used to wash down the growth. The suspension, kept at room temperature, was shaken at intervals and centrifuged at the end of a week.