Metabolism of brassinosteroids in plants

Brassinosteroids represent a class of plant hormones. More than 70 compounds have been isolated from plants. Currently 42 brassinosteroid metabolites and their conjugates are known. This review describes the miscellaneous metabolic pathways of brassinosteroids in plants. There are some types of metabolic processes involving brassinosteroids in plants: dehydrogenation, demethylation, epimerization, esterification, glycosylation, hydroxylation, side-chain cleavage and sulfonation. Metabolism of brassinosteroids can be divided into two categories: i) structural changes to the steroidal skeleton; and ii) structural changes to the side-chain.