COMPARABLE GROWTH OF A TRICHOMONAS-VAGINALIS STRAIN IN PEHPS AND TYI-S-33 MEDIA

PEHPS medium, developed for axenic cultivation of I Entamoeba histolyt ica and E. invadens, was also capable of supporting the growth of a Tr ichomonas vaginalis strain, with an inoculum of 1 to 100 trichomonads/ ml. The logarithmic growth phase in PEWS or in TYI-S-33 medium lasted 72 h; yield (3.33 +/- 0.56 x 10(6) trichomonads/ml), duplication time (4.27 h), number of duplications (16.85), or increase ratio (33,328) i n PEHPS medium showed no significant differences with those obtained i n TYI-S-33 under similar culture conditions. Accordingly, PEHPS medium might be used for the axenic cultivation of T. vaginalis.