Soursop (also called graviola, guyabano, and in Hispanic America ) is the fruit of Annona muricata, a broadleaf, flowering, evergreen tree. It is native to the tropical Americas and is widely propagated.
The fruit is oval, dark green when immature, with a leathery, inedible skin that turns yellow-green during maturity. Their flesh is juicy, acidic, whitish, and aromatic somewhat like pineapple, although with a unique earthy aroma. To aid soursop breeders and stimulate further development of genomic resources for this globally important plant family, the complete genome for Annona muricata was sequenced in 2021.
Uses
Culinary
The flesh of the fruit consists of an edible, white pulp, some fiber, and a core of indigestible black seeds. The pulp is also used to make fruit nectar, smoothies, fruit juice drinks, as well as candies, sorbets, and ice cream flavorings. The leaves of Annona muricata contain annonamine, which is an aporphine-class alkaloid containing a quaternary ammonium group. The plant also contains lichexanthone, a compound in the xanthone class.
Neurotoxicity
The Memorial Sloan-Kettering Cancer Center cautions, "alkaloids extracted from graviola may cause neuronal dysfunction". Annonacin has been shown in laboratory research to be neurotoxic. In 2010, the French food safety agency concluded that "it is not possible to confirm that the observed cases of atypical Parkinson syndrome ... are linked to the consumption of Annona muricata".
thumb|[[Annonacin, a neurotoxin found in soursop]]
Controversy
In 2008, the Federal Trade Commission in the United States stated that use of soursop to treat cancer was "bogus", and there was "no credible scientific evidence" that the extract of soursop sold by Bioque Technologies "can prevent, cure, or treat cancer of any kind." Also in 2008, a UK court case relating to the sale of Triamazon, a soursop product, resulted in the criminal conviction of a man under the terms of the UK Cancer Act for offering to treat people for cancer. A spokesman for the council that instigated the action stated, "it is as important now as it ever was that people are protected from those peddling unproven products with spurious claims as to their effects."
The Memorial Sloan-Kettering Cancer Center and Cancer Research UK state that cancer treatment using soursop is not supported by reliable clinical evidence.