Effects of a New Tetrazolium Derivative on Tissue, Bacteria, and Onion Root Tips

Abstract
A new tetrazolium derivative, Neotetrazolium (NT), 4,4[image]-di(3,5-diphenyltetrazole)-biphenyl dichloride, was used in place of the nitroprusside reaction for testing active -SH groups in tissue. NT produced a stable purple to black and the stained tissue could be fixed without loss of color. Being non-toxic, it could be used in vivo. Detailed pathologic data are given for supravital tissues and in mice following intraperit. injn. In bacteria black inclusion bodies were found as well as other morphologic changes similar to those produced by penicillin. On plates, Staphylococcus aureus gave a clear zone surrounded by a black ring. The black color produced in both plant and animal tissues was due to the formation of formazan.