CONTROL OF MOS BY CHEMICAL AGENTS CONTD...

F) DYES:  They are important as staining reagents & in lab media. Two classes of dyes that have antimicrobial properties are;
1) Triphenyl Methane Dyes:   It includes Malachite green, brilliant green, & crystal violet. These dyes are more toxic to Gram positive than Gram negative bacteria.  It is used in certain media to make it selective( especially crystal violet is used in Mac Conkey agar  as selective substances).  Crystal violet has been used as fungicide & used to treat thrush caused by Candida albicans .  The actual mechanism of mode of action is unclear. However, they may interfere with cellular oxidation process. Please visit this links; http://en.wikipedia.org/wiki/Triphenylmethane.  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC373988/

                

                                          Fig: Triphenyl Methane Dyes 
2) Acridine Dyes: It includes Acriflavine & Tryptoflavine. They are commonly used for selective inhibition of Staphylococci & Gonococci. They are used to treat burns, wounds, & ophthalmic preparation.  They act by combining with DNA.  Please visit this links:
http://en.wikipedia.org/wiki/Acridine
http://jac.oxfordjournals.org/content/47/1/1.long 





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