[Verification of the preparation of Streptococcus pyogenes str. A1 96/50 based on the results of growth properties of media]. / Overení prípravy kultury Streptococcus pyogenes Str. A1 96/50 na výsledek zkousky rustových vlastností pud.

For tests of the growth properties of media Czechoslovak standards prescribe a culture of the Streptococcus pyogenes strain Str. A1 96/50 which must be shaken with sea sand and diluted with a gelatin solution. The author found that shaking the culture with sea sand usually reduces significantly (P less than 0.05) the number of colonies in agar medium, as compared with a culture which did not have this treatment. The author also found that there is no significant difference (P greater than 0.05) in the number of colonies when the culture is diluted with a gelatin solution or isotonic sodium chloride solution. He proved that there is no significant difference (P greater than 0.05) in the scatter of the number of colonies in agar when the culture is shaken with sea sand or if it is diluted with a gelatin solution, as compared with a culture not shaken with sand or diluted with sodium chloride solution.