Sour sop; The Cancer Fighting Fruit Tree
In April 2010 the world was introduced in dramatic fashion to a fruit tree, which was supposed to cure all forms of cancer. The news came in the form of an e-mail that went viral. According to the email, an unnamed drug company had done extensive research on this fruit and found it very effective against cancer. However, because they were unable to do a synthetic version of the fruit tree the research was dropped and its results never published.
The e-mail went on to say that in 1976 the US National Cancer Institute conducted its own scientific research and the results showed that the plant’s “leaves and stems were found effective in attacking and destroying malignant cells.” Although the results were supposedly published in an internal report, it was never released to the public, according to the e-mail. Whether the e-mail is true or not, the fruit tree known as the sour sop variously called guyabano or graniola (scientific name: Anona muricata) has been identified by the US National Academy of Sciences (NAS) as one of the fruits that deserves attention. Found deep in the Amazon jungle and grown extensively in the Caribbean and East Asia, the sour sop has for centuries been used by local medicine doctors to cure all manner of ailments.
In the Caribbean it has been used to combat high blood pressure, and to heal skin rashes, the crushed fresh leaves are applied directly on the skin for faster healing. It is also used in the fight against insomnia. Sour sop extracts are considered to be antispasmodic, sudorific and emetic. In some communities the leaves are even boiled and employed to kill bedbugs and head lice.
To reduce fever, the leaves are boiled and taken internally or the leaves are added to bathing water and is said to have the same effect. Young sour sop leaves are also applied on the skin to alleviate rheumatism and other skin infections like eczema. Applied during the healing of wounds, this can result in less or no skin scars. The decoction can also be used as a wet compress on swollen feet and other inflammations.
The juice of the fruit is taken orally as a herbal remedy for urethritis, haematuria and liver ailments. Pulverizing the sour sop seeds and mixing it with soap and water is used as effective spray against caterpillars, armyworms and leafhoppers on plants.
While the traditional uses of the drugs are well known, the scientific community is beginning to take notice. In a recently concluded study from Purdue University, researchers were able to show that the sour sop leaves are able to kill cancer cells effectively, particularly cancer cells in the prostate, pancreas, and lung.
This latest findings from the scientific community strengthens earlier work undertaken that showed extracts of the sour sop tree to have antiviral (1), antiparasitic, antirheumatic, astringent, emetic (2), antileishmanial and cytotoxic (3) (4) effects. The ethanolic extract of Annona muricata was found to inhibit the Herpes simplex virus. Soursop has also been shown to be effective against multidrug resistant cancer cells line (5) (4).
Extracts were also shown to be lethal to the fresh-water mollusk, which acts as a host for the parasitic worm Schistosoma mansoni (2). Alkaloids from sour sop have been shown to be detrimental to the survival of dopaminergic nerve cells in vitro. (6). Soursop extracts have also been shown to be effective against the growth of Adriamycin resistant human mammary adenocarcinoma (MCF-7/Adr) by blocking the cancer cell’s access to ATP and by inhibiting the actions of plasma membrane glycoprotein (5). It may also have antidepressive activity due to its ability to stimulate serotonine receptors (7).
Despite the many proven properties of the sour sop and its impressive scientific record, oddly enough, there are no large scale studies in humans on the effects of what must be considered the wonder tree. As in every good thing here are some words of warning: research carried out in the Caribbean has suggested a connection between consumption of sour sop and some forms of Parkinson’s disease due to the very high concentration of annonacin. Scientists therefore warn against extensive consumption of the fruit. The seeds are also considered to be toxic and should not be consumed.
1. Padma P, Pramod NP, Thyagarajan SP, Khosa RL. Effect of the extract of Annona muricata and Petunia nyctaginiflora on Herpes simplex virus. J Ethnopharmacol. 1998;61:81-3.
2. dos Santos AF,.Sant’Ana AE. Molluscicidal properties of some species of Annona. Phytomedicine. 2001;8:115-20.
3. Jaramillo MC, Arango GJ, Gonzalez MC, Robledo SM, Velez ID. Cytotoxicity and antileishmanial activity of Annona muricata pericarp. Fitoterapia 2000;71:183-6.
4. Liaw CC, Chang FR, Lin CY, Chou CJ, Chiu HF, Wu MJ et al. New cytotoxic monotetrahydrofuran annonaceous acetogenins from Annona muricata. J Nat.Prod. 2002;65:470-5.
5. Oberlies NH, Chang CJ, McLaughlin JL. Structure-activity relationships of diverse Annonaceous acetogenins against multidrug resistant human mammary adenocarcinoma (MCF-7/Adr) cells. J Med Chem. 1997;40:2102-6.
6. Lannuzel A, Michel PP, Caparros-Lefebvre D, Abaul J, Hocquemiller R, Ruberg M.Toxicity of Annonaceae for dopaminergic neurons: potential role in atypical parkinsonism in Guadeloupe. Mov Disord. 2002;17:84-90.
7. Roman G. Tropical myeloneuropathies revisited. Curr.Opin.Neurol 1998;11:539-44.