Malachite Green Definition Biology

The alcohol produced here is important because it helps malachite green cross cell membranes. Once inside the cells, it is usually metabolized into leuko-malachite green. One thing to remember is that only the malachite green composite version is deeply colored green. Other derivatives than green leuco and malachite alcohol are not. This difference is that the cationic form of the compound prolongs pi delocalization, through which the molecule absorbs visible light. There are several other anecdotal reports of contact reactions to gentian violet, particularly in the older literature [45A,46A,47A], and bright green [48A]. In one case, there was co-existing nickel sensitivity [49A]. Until recently, contact dermatitis in a 28-year-old Chinese woman without allergies was attributed to gentian violet [50A]. However, in 1992, Canada was found to pose a significant health risk to people who ate fish contaminated with malachite leaves.

The chemical has been classified as a Class II health risk because it is toxic to human cells and could cause liver tumors to form. However, due to its simple and low manufacturing cost, it is still used for non-aquaculture purposes in some countries with less restrictive laws. In 2005, eels and fish imported from China and Taiwan were found in Hong Kong with traces of this chemical. In 2006, the U.S. Food and Drug Administration (FDA) discovered malachite green in seafood imported from China for human consumption in that country, where the use of the substance is also banned in aquaculture. In June 2007, the FDA blocked the importation of several varieties of seafood due to persistent malachite green contamination. [1] [2] The substance has been banned in food-related uses in the United States since 1983. Some formalin products are FDA approved for fish. Malachite green, commonly associated with formalin, has a high regulatory priority and should be avoided. Taken together, these data suggest that the N-demethylated metabolites of leuko-malachite green and malachite green may undergo metabolic activation, similar to carcinogenic aromatic amines, i.e. oxidation to metabolites that react with DNA directly or after esterification.

However, the adduct was not characterized because existing in vitro mutagenicity tests and metabolic activation systems failed to activate leuko-malachite green or malachite green for DNA-damaging species (Culp and Blankenship, unpublished results). Malachite green is an organic compound used as a dye and controversial as an antimicrobial agent in aquaculture. Malachite green is traditionally used as a dye for materials such as silk, leather, and paper. Despite its name, the dye is not made from the mineral malachite; The name comes only from the similarity of the color. Malachite Green A green dye used to stain bacteria and as an antibacterial and antifungal treatment. The leukoform of malachite green was first produced in 1877 by Hermann Fischer by condensing benzaldehyde and dimethylaniline in a molecular ratio of 1:2 in the presence of sulfuric acid. [3] In forensic medicine, leuko-malachite green is used as a method of detecting latent blood. Hemoglobin in the blood catalyzes the reaction between leuko-malachite green and hydrogen peroxide. It converts the colorless LMG to malachite green. If the green color appears, it is an indication of the presence of blood in the sample.

Malachite green is a synthetic organic dye with antifungal activity. In fish farming, this agent has been used for a long time, but is largely out of use due to its mutagenic properties. The study of malachite green toxicity in fish has been difficult because it is strongly influenced by water hardness, pH, temperature and the amount of dissolved oxygen in the water. Detailed studies have shown that the toxicity of the chemical increases as temperature rises or pH decreases. The effects of malachite green on fish eggs have also been tested and it has been shown that a double increase in malachite green concentration could lead to up to 20 times the mortality of rainbow trout eggs. This shows that it can be extremely toxic to certain species of fish and in particular to fish eggs. Other effects such as carcinogenesis, mutagenesis and decreased fertility have been reported in rainbow trout. Although malachite green is an extremely effective weapon against fungal and parasitic infections in fish, the chemical also causes serious side effects in fish. MG is active against oomycete saprolegnia, which infects fish eggs in commercial aquaculture, MG has been used to treat saprolegnia and is used as an antibacterial agent. [5] It is a very popular treatment against Ichthyophthirius multifiliis in freshwater aquariums. The main metabolite, leuko-malachite green (LMG), is found in fish treated with malachite green, and this discovery is the basis of controversy and government regulation. See also Antimicrobials in aquaculture.

The determination of malachite green aims to measure the inorganic phosphate content in a solution. This colorimetric method is based on the formation of a green complex when malachite green molybdate reacts with inorganic phosphate under acidic conditions (Fig. 1B). The amount of green molybdophosphoric acid complexes can be measured with a spectrophotometer at 620 nm and is directly correlated with the concentration of free inorganic phosphate in the reaction. Since CD73 catalyzes the degradation of AMP to adenosine and inorganic phosphate, malachite green assay can be used to measure inorganic phosphate produced by CD73 enzyme activity. When malachite green is used in aquatic animals, it is metabolized to leuko-malachite green.