Custard apple is a hybrid between Annona cherimola and Annona squamosa plants. The Annona spp., including A. squamosa, A. muricata, and A. cherimola, contain acetogenin alkaloid compounds with anticancer properties.
Once such alkaloid, bulatacin, was shown to possess antitumor potential against cancerous liver tumors (Chih et al., 2001). Annona muricata leaves destroy colon cancer cells (Moghadamtousi et al., 2014). Acetogenins were also reported to eliminate human hepatoma cell lines (Liaw et al., 2002).
The fruit contains small amounts of neurotoxic alkaloids, and consuming large quantities of the fruit could cause Parkinson-like symptoms (Memorial Sloan-Kettering Cancer Center, 2011; Champy et al., 2005).
Plants are often the starting research point in a drug discovery process. The identification of molecules with medicinal properties should not be taken that consumption of that plant will help treat a patient. Molecules need to be tested for safety, efficacy, and side effects.
In most cases, the concentration of a bioactive compound in a plant is not adequate to cause any meaningful impact on a health condition.
Take the information on the medicinal property of an individual plant for knowledge. Alternate medicines should only be consumed if tested and approved by a credible regulator. Most herbal medicine recommendations have not been adequately tested and can cause more harm than good.