[2][3] The phomoxanthones are structurally closely related to the secalonic acids, another class of dimeric tetrahydroxanthone mycotoxins, with which they share several properties.

Notably, both the phomoxanthones and the secalonic acids are unstable when dissolved in polar solvents such as DMSO, with the covalent bond between the two monomers shifting between 2,2′-, 2,4′-, and 4,4′-linkage.

The aqueous phase is then dried and the residue is dissolved in EtOAc, washed with H2O, concentrated and repeatedly purified by size-exclusion chromatography.

[2] It showed strong antibiotic activity against a multidrug-resistant strain of the main causative agent of malaria, the protozoan parasite Plasmodium falciparum.

A later study also reported antibiotic activity for PXA against the alga Chlorella fusca, the fungus Ustilago violacea, and the bacterium Bacillus megaterium.

[8] This broad range of activity disqualified it as a specific antibiotic that could be used in the treatment of infectious diseases, however the hope that it could be used as an anti-cancer drug remained.

A recent study has shown that PXA directly affects the mitochondria by disrupting both their biochemical functions and their membrane architecture.

[10][11] One of the main functions of the mitochondria is to produce the cellular energy currency ATP through the process of oxidative phosphorylation (OxPhos).

OxPhos depends on the mitochondrial membrane potential, which is generated by the electron transport chain (ETC) via the consumption of oxygen.