peptones and malachite-green

Nash and Snyder medium and malachite green agar 2.5 ppm medium, a new selective culture medium designed in our laboratory, were challenged with pure cultures of Fusarium moniliforme strains and two different mixed-conidium suspensions, which included rapidly spreading fungi, for their utility in the isolation and enumeration of F. moniliforme. From the results of this comparative study, malachite green agar 2.5 ppm allowed only the selective growth of F. moniliforme whereas Nash and Snyder medium allowed both the growth of F. moniliforme and other species not belonging to Fusarium spp. The enumeration of F. moniliforme propagules was similar in both culture media.

Topics: Agar; Culture Media; Fusarium; Nitrobenzenes; Peptones; Rosaniline Dyes; Selection, Genetic; Soil Microbiology; Spores, Fungal

On the basis of the available literature, the history of development of the Rappaport--Vassiliadis (RV) medium, its preparation and applicability in food control methods were described. Results of comparative studies on the effectiveness of Salmonella isolation upon use of different specifically-multiplying media: MK, medium containing sodium acid selenite, R25/37 degrees C, RV, were presented. The number of Salmonella isolations in samples multiplied in RV medium was found to exceed that obtained upon use of the remaining media. Moreover, RV medium was easy to prepare; it proved to be economical and was stable for up to 7 months when refrigerated.

Topics: Culture Media; Drug Combinations; Food Microbiology; Humans; Magnesium Chloride; Peptones; Phosphates; Potassium; Potassium Compounds; Rosaniline Dyes; Salmonella Food Poisoning; Salmonella typhimurium; Sodium Chloride; Solutions; Temperature; Time Factors