Altersolanol A is a phytotoxic tetrahydroanthraquinone isolated from a number of plant pathogens belonging to the genera Alternaria, Phomopsis, Dactylaria, Stemphylium, Ampelomyces and Pleospora. Altersolanol A is a potent stimulator of NADH oxidation in mitochondria and exhibits potent in vitro cytotoxicity against a broad range of human cancer cell lines. Altersolanol A acts as a kinase inhibitor, induces cell death by apoptosis through the cleavage of caspase-3 and -9 and decreases anti-apoptotic protein expression.