Malachite green metabolized into LMG. Only the cation MG is deeply colored, whereas the leuco and alcohol derivatives are not. This difference arises because only the cationic form has extended pi-delocalization, which allows the molecule to absorb visible light. The leuco form of malachite green was first prepared by Hermann Fischer in 1877 by condensing benzaldehyde and dimethylaniline in the molecular ratio 1:2 in the presence of sulfuric acid. Malachite green is traditionally used as a dye. Kilotonnes of MG and related triarylmethane dyes are produced annually for this purpose. MG is active against the oomycete "Saprolegnia", which infects fish eggs in
Malachite sunbird sunbird species can take nectar by hovering like a hummingbird, but usually perch to feed most of the time. As a fairly large sunbird, the malachite sunbird is no exception. They have long thin down-curved bills and brush-tipped tubular tongues, both adaptations to nectar feeding. Some plant species from which malachite sunbirds feed include many "Aloe" species, such as "Aloe broomii", "Aloe ferox" and "Aloe arborescens", and "Protea" species, such as "Protea roupelliae" as well as various other bird-pollinated plants such as "Leonotis" and "Strelitzia". It has been suggested that their behaviour of guarding flowering plants may have led to