Tyrothricin was later found to be a mixture of the peptides gramicidin and tyrocidine. These were observed to have toxic effects in red blood cells and reproductive cells in humans, however, if applied externally as an ointment tyrocidine could also be used as a potent antimicrobial agent.
Tyrothricin was later identified as a combination of peptides gramicidin and tyrocidine. These compounds were found to have toxic effects on human red blood cells and reproductive cells, but when applied topically in the form of an ointment, tyrocidine exhibited potent antimicrobial properties.