Description Application Leucocrystal Violet has been used to identify histamine-producing lactobacilli in cheese. Packaging 5, 25 g in glass bottle Biochem/physiol Actions Leucocrystal Violet (LCV) is a cationic triarylmethane dye. LCV is a reduced form of gentian violet (crystal violet) and thus, it is colorless. It has an affinity for both cellulosic and proteinaceous materials. LCV and hydrogen peroxide react with the hemoglobin in blood and turn the blood impression to purple/violet color. Therefore, the dye is widely used to stain blood residue on both porous and non-porous materials. Caution Photo-ionization can cause color variations