Monensin sodium is an antiprotozoal agent produced by Streptomyces cinnamonensis.Monensin sodium salt (Monensin A sodium salt) causes a marked enlargement of the MVBs and regulates exosome secretion

Monensin sodium salt (Coban), isolated from Streptomyces cinnamonensis, is a well-known representative of naturally polyether ionophore antibiotics. Monensin is an ionophore related to the crown ethers with a preference to form complexes with monovalent cations such as: Li+, Na+, K+, Rb+, Ag+, and TI+. [1] Monensin A is able to transport these cations across lipid membranes of cells, playing an important role as an Na+/H+ antiporter. It blocks intracellular protein transport, and exhibits antibiotic, antimalarial, and other biological activities. [2] The antibacterial properties of monensin and its derivatives are a result of their ability to transport metal cations through cellular and subcellular membranes. [3]

LD50: Mice 335 mg/kg (i.g.) [4]; Rats 36.5 mg/kg (i.g.); Chickens 185 mg/kg (i.g.). [5]