Handbook of Culture Media for Food and Water Microbiology
Chapter T1: Thallous acetate Tetrazolium Glucose (TlTG) agar
-
Published:06 Dec 2011
-
Special Collection: 2011 ebook collection , 2011 ebook collection , 2011-2015 food science subject collection
2011. "Thallous acetate Tetrazolium Glucose (TlTG) agar", Handbook of Culture Media for Food and Water Microbiology, Janet E L Corry, Gordon D W Curtis, R M Baird
Download citation file:
This monograph has been assessed by members of the IUMS–-ICFMH Working Party on Culture Media and given ‘Approved’ status.
The medium incorporates thallous acetate as a selective inhibitory agent (Barnes, 1956). Differentiation between Enterococcus faecalis and Enterococcus faecium depends upon the reduction of tetrazolium to the maroon formazan at pH 6.0. Selectivity of the medium can be increased by incubation at 44–45°C.
The peptone and beef extract powder are dissolved by boiling in half the required volume of water, making allowance for additions (a)–(c) below. The pH value is adjusted to 6.0–6.1. The agar is dissolved separately and the two solutions are mixed and distributed into bottles (or final containers) in 92 mL amounts for autoclaving at 121°C for 15 min. After cooling to 50–52°C, the following solutions are added to each 92 mL of molten basal medium:
