Fresh soursop (top)and Freeze Dried soursop (bottom)

Freeze Dried Soursop – Everything you wanted to know

Freeze dried soursop is a rare and usually food product indeed. As more and more people discover the wonderful benefits of soursop fruit and soursop leaves they start wondering what other foods come from the tropical fruit tree. The answer is freeze dried soursop fruit.

So what is freeze dried soursop fruit?

It is the soursop fruit pulp dried using a desiccating process called freeze-drying.  A low-temperature dehydration process is used on food products to remove water – it involves freezing the product, lowering pressure, then removing the ice by sublimation (ice turns into gas). This is in contrast to dehydration using heat to remove water. The freeze dried end product is pieces of soursop pulp that look like popcorn or chips. It is dry, crunchy, and sweet. But yet the freeze-drying process retains 99% of the nutrients compared to the fresh product.

Why do people eat foods made from the soursop tree, including its fruit and leaves?

The most famous compounds found in the tree. It is called acetogenin compounds (AGEs). Acetogenins block nicotinamide adenine dinucleotide, which is part of the membrane of cancer cells. Soursop has high concentrations of AGEs, found is in its fruit, stems and leaves.

Soursop fruit also contains many minerals, including calciummagnesium, and iron. In one cup of the fruit (or about 1/8 of a cup of freeze dried soursop) provides 46.4 milligrams (mg) of vitamin C in one cup of soursop pulp, which is over half the recommended daily amount for adults. For context, women need 75 mg of vitamin C per day, and men need 90 mg.

Advantages of  freeze dried soursop fruit

One of the challenges with soursop fruit is that it only grows in tropical and sub-tropical climates. You might see a soursop tree in Florida in the U.S., but even then it’s rare. The tree is very sensitive to temperature so if it gets cold enough to see frost on the ground then it means that a soursop tree will not thrive in that environment even if the rest of the year temperatures are in the 80s and 90s (25 to  35 C).

soursop fruit on tree

Soursop fruit on a tree in Malaysia

So the fruit has to be grown in the tropics. However, that means it is grown in South America, the Caribbean, and equatorial Asia (like Malaysia) and Africa. Soursop is a large fruit and it is heavy with water. It also has a thick green spiny skin. So shipping it in its fresh form can be expensive.

The advantage that freeze dried soursop fruit has is that the water is removed in the freeze drying process. Freeze-drying process and so it is light like a chip and crunchy too. So it is much cheaper to ship.

Where can I buy freeze dried soursop fruit?

You can buy freeze dried soursop fruit from specialty food suppliers like in the U.S. and from in Canada.

soursop leaves

Soursop leaves and fruit on a farm in Malaysia

If you have ever wondered how soursop grows, here’s documentary evidence from a visit our family made to the farm where we have been buying soursop leaves and soursop tea bags for more than three years for our stores at (USA) and (Canada).

You’ll see below that soursop is both a large green fruit and the tree it is grown on. Some people call it graviola. The graviola tree and graviola fruit is the same thing as soursop. Just a different name. Same fruit and same plant.

Here is a gallery of our visit to the farm which is located in south Malaysia in the hills of Johor province. Across the strait is Singapore.


Guanabana leaves can be harvested from the graviola tree, a tall tropical evergreen tree that grows 15 to 18 ft (5 to 6 meters) in height.
The guanabana leaves produces a large heart-shaped edible guanabana fruit that is 6 to 9 inches long. The inedible skin is yellowish green in color. Inside is white flesh dotted with 3/4 inch black or brown seeds.

You can find the fruit in most of the warmest tropical areas in South and North America including the Amazon, the Caribbean and Mexico. It also grows in south Florida.
It can also be found in local markets in the tropics.  Sometimes guanabana fruit is referred to as soursop, custard apple, custard pear, paw paw, or sometimes Brazilian cherimoya.
What is the guanabana fruit used for in the kitchen?

Guanabana fruit is excellent for making drinks, ice creams and and frozen desserts. Though it can be slightly sour and acidic, as it ripens , it can be eaten raw.
All parts of the graviola tree aru used in natural medicine, including bark, leaves, roots, fruit and seeds. Different properties and uses are attributed to the different parts of the tree.
What is guanabana used for in natural medicine?

The guanabana fruit and fruit juice can be eaten to treat worms and parasites, to cool fevers, to increase mother’s milk after childbirth. It is also used to treat diarrhea and dysentery.
The crushed guanabana seeds are used to treat internal and external parasites and worms.
The graviola bark, leaves and roots can be used as a sedative, as an antispasmodic, to lower blood pressure and to calm nerves. A guanabana leaf tea is consumed for those purposes.
History of guanabana in regional natural medicine

Guanabana has a long rich history of use in herbal medicine, and among indigenous peoples in the tropics.

You find  that a tea from the guanabana leaf is used for mucus reduction in the Peruvian Andes. The crushed seeds of the fruit are used to kill parasites. In the Peruvian Amazon the bark roots and leaves are used for diabetes and as a sedative and antispasmodic.


Indigenous tribes in Guyana use a leaf or bark tea of guanabana as a sedative and heart tonic.

In the Brazilian Amazon, the guanabana leaf tea is used for liver problems and the oil of the leaves and unripened fruit is combined with olive oil. It is used externally for neuralgia, rheumatism and to treat arthritis pain.

Jamaica and Caribbean islands

In the Caribbean, especially in Jamaica, Guanabana fruit and its juice has long been used to treat:
to bring in mother’s milk.
to ease diarrhea.
And, to treat cancer
Plus, the bark or leaves can be used as an antispasmodic, as a sedative, and to soothe nerves. It is also used for heart conditions, coughs, difficult childbirth, asthma, asthenia, hypertension and to clear parasites.


Annonaceous Acetogenins

Annonaceous Acetogenins

Within the 212 compounds that were isolated from different parts of the plant, acetogenins (AGEs) were reported to be the major phytochemicals, followed by alkaloids and phenols (). These secondary metabolites were first isolated from multiple parts of plants belonging to the Annonaceae family in 1982 by Tempesta, and acetogenins were further determined to have toxicity towards the P-388 lymphocytic leukaemia in mice (). Since then, more than 120 AGEs have been identified from ethanol, methanol or organic-based extracts from different parts of the plant, ranging from the leaves and the seeds () to even the fruit’s outer skin.

AGEs were later determined to be metabolites that can be distinguished by the presence of a methyl-substituted α,β-unsaturated γ-lactone (). Since their discovery, more than 500 AGEs have been discovered from different parts of the plant (). These metabolites were later classified into several groups on the basis of the availability of tetrahydrofuran (THF) and hydroxyl groups, as well as on factors such as the terminal γ-lactone ring and the characteristics aliphatic chain substituents (). On the basis of these characteristics, AGEs can be divided into 10 different types, which include 1) linear AGEs (AGEs without the THF rings), 2) epoxy-AGEs (without THF rings), 3) AGEs with mono-THF α,α′-dihydroxylated γ-lactone, 4) AGEs with a mono-THF α-hydroxylated γ-lactone, 5) AGEs with mono-THF and several lactone moieties, 6) AGEs with a neighbouring bis-THF α,α′-dihydroxylated γ-lactone, 7) AGEs with a neighbouring bis-THF α-hydroxylated γ-lactone, 8) AGEs with a non-adjacent bis-THF γ-lactone, 9) AGEs with a saturated lactone bis-THF and 10) miscellaneous AGEs ().

Multiple forms of AGEs have been studied for their mechanisms that can be used against particular targets, such as insects and tumour cells. Acetogenins have been shown to be very effective against insects and can be used as insecticides and insect repellent. Multiple parts of the plant, including the roots, leaves, unripe fruits and seeds, have been shown to have insecticide and insect repellent properties (), (), (). Against the larva of the moth Plutella xylostella, a pest of cabbage, 5 mg/mL ethanolic extracts of A. muricata leaves were proven to be effective in killing 100% of the larvae tested. Further tests using lower concentrations of the ethanolic extracts even showed an ability to significantly reduce the survival of the larvae population (). Crude extracts from the plant were also shown to be effective against Aedes aegypti, in combination with silver nanoparticles, which makes A. muricata extracts a good candidate to be used to control the spread of dengue fever (). A similar anti-parasitic effect was also observed when methanolic extracts of the seed were used against Entamoeba histolticaMolinema dessetae and Artemia salina, which was later deduced to be due to the presence of acetogenins (). The role of acetogenins in inhibiting the growth of insect larvae was suggested to be due to the THF ring inhibition of the mitrochondrial complex I through NADH oxidase inhibition ().

The capacity of acetogenins to inhibit NADH oxidase was also shown to be important for their anti-tumour function. The inhibition of NADH function is evident, as reported by Morré et al. (1995). The report suggested that exposure to an acetogenin called bullatacin specifically inhibited NADH oxidase enzyme functions isolated from Hela cells as HL-60 cancer cells ().

Acetogenins were also shown to be capable of blocking ATP production in mitochondria. This mechanism of action was shown to be effective against cancer cells that produce higher amounts of ATP in comparison to normal cells, thus limiting the ability of cancer cells to grow (). Interestingly, AGE toxicity was observed in the cancer cells, with a minimal negative impact on the normal cells. Studies using AA mimetics have suggested that acetogenin analogues synthesised in vitro have shown toxicity towards the HCT-8 and HT29 cell lines, with negative toxicity towards the normal human cell line HELF (). Similarly, a study using A. muricata leaf extracts also showed toxicity towards cancer cell lines MCF-7, MDA-MB-231 and 4 T1, but less toxicity towards the normal breast cell, MCF10A (), which shows that these AGEs specifically target cancer cells, not normal cells. These observations thus suggest the potential use of AGEs as treatment options against cancer.

Annona muricata and Its Biological Properties against Cancer

A dysfunctional apoptotic pathway is one of the main contributors to carcinogenesis. The inability of cells to execute apoptosis to remove cancer cells was observed in multiple cancer types, including breast, pancreatic, ovarian and colorectal cancers (). This occurrence creates imbalances between cell proliferation and cell death and can be caused by disruptions in the normal functions of the apoptotic pathway. Similar to other types of cancer, failure to carry out apoptosis in breast cancer cells might be attributed to the disruptions within the apoptotic pathway. Defects within the intrinsic pathway, for example, have been associated with the progression of breast cancer. Defects in the regulation of cytochrome release (), apoptosome formation () and caspase activation () have all been shown to be present within breast cancer cells.

The capability of inducing cancer cell cytotoxicity has been one of the main reasons behind the increased interest among scientists in the benefits of CAM, especially plant-based CAMs. A. muricata leaves, among other CAMs, are good candidates to treat cancer caused by viruses. Extracts from A. muricata leaves were shown to have the capacity to induce apoptosis in Hela cells, suggesting that the extracts have the potential to be used as a treatment against virus-induced cancer cells (). Such a potential was also evident in the prevention of skin papillomagenesis in laboratory mice. In this study, ethanolic extracts of A. muricatawere shown to inhibit tumour growth in a two-stage skin papillomagenesis model, as evidenced by the presence of only slight hyperplasia in mice groups treated with A. muricata extracts in comparison to an untreated mice group ().

Breast Cancer

In terms of specific effects against breast cancer, several studies have indicated the potential use of this plant in potential therapeutic treatments in patients. Extracts from A. muricata were shown to inhibit the proliferation of breast cancer cells by inducing cytotoxic activity in lung cancer cell lines (). Gomes further reported that A. muricata extracts have the most cytotoxic effect when compared to extracts from Lantana camara, Handroanthus impetiginosus and Mentzella aspera. A separate study by Rachman showed that the ethanol extracts of leaves of the soursop plant extracted into ethanol induce cytotoxic activity within the breast cancer cell line MCF7 (). Another study by Gavamukulya also showed that a similar ethanol extract of the soursop plant leaves was found to be highly cytotoxic in vitro against the two human breast cancer cell lines MDA and SKBR3 ().

Liver Cancer

The cytotoxic effect of the plant’s extracts were also proposed by multiple in vitro studies using cultured liver cancer cells, suggesting that they can potentially be used as a treatment option against liver cancer. The growth and viability of the liver cancer cell HepG2 was shown to be inhibited following incubation with an ethanol extract of A. muricata. The cytotoxic effect observed in the HepG2 cell line was suggested to be a result of induction of the apoptosis pathway through the production of reactive oxygen species (ROS) (). In a separate study using a similar cell line, Liu () also demonstrated the capability of A. muricata extracts to induce apoptosis. The study showed that the treatment of HepG2 resulted in the up regulation of heat shock protein 70 (HSP70), glucose-regulated protein 94 (GRP94) and protein disulphide isomerase 5 (PDI-related protein 5). A bioinformatic analysis of the up-regulation of these proteins suggested that the treatment of HepG2 cells with A. muricata extracts can trigger the apoptotic pathway by means of endoplasmic reticulum (ER) stress ().

Prostate Cancer

Graviola leaf extract (GLE), flavonoid-enriched extract and acetogenin-enriched extract (AEF) administered in vivo and in vitro were also shown to negatively affect the proliferation of prostate cancer. A study conducted by Yang () suggested that GLE, FEF and AEF all showed the capacity to down-regulate prostate cancer, with GLE being the most efficient at doing so. This study not only showed the efficacy of A. muricata extracts at inhibiting prostate cancer but also the importance of using whole-leaf extracts to achieve the highest inhibitor efficacy in combating cancer ().

Pancreatic Cancer

A. muricata-induced cytotoxicity in cancer cells has also encouraged scientists to further examine the molecular pathways that lead to such observations. According to a study conducted by Torres (), the activation of extracellular signal-regulated kinases (ERK) and the phosphatidylinositol 3′kinases (PI3K/Akt) pathways play a crucial role in the proliferation and survival of pancreatic cancer cell, and the inhibition of these pathways leads to the inhibition of pancreatic cell growth. A similar study also revealed that the treatment of pancreatic cancer cells with A. muricata extracts resulted in a decrease in the activation of both ERK and Akt pathways in pancreatic cancer cells. Thus, the inhibition of these pathways is in agreement with the decreased viability of pancreatic cancer cells treated with the plant extract (). Besides that, A. muricata was also shown to inhibit metastasis. A study performed on pancreatic cancer cells by Torres showed that the migratory capacity of pancreatic cancer cells was reduced after treatment with a graviola extract, as evaluated by a transwell assay, suggesting that the natural extract reduces the motility of pancreatic cancer cells. The motility and migration of cancer cells is associated with the arrangements of the cortical actin and microtubules network. Additionally, cellular ATP depletion has been associated with a reorganisation of the actin cytoskeleton and a suspension of the dynamics of microtubules, which is known to induce mitotic arrest. Thus, graviola extracts cause a disruption of the cortical actin network that can inhibit the motility of cancer cells ().

Lung Cancer

Moghadamtousi showed that A. muricata induces apoptosis in lung cancer cells (). This finding was confirmed by high-content screening (HCS) multiple cytotoxicity analyses that examined the characteristics of apoptosis before and after treatment with A. muricata extracts, including nuclear condensation, mitochondrial membrane potential (MMP), cytochrome c leakage and perturbation in membrane symmetry. The analyses showed that A549 cells treated with A. muricata extracts experience inhibition in growth capability as well as up-regulation of the apoptosis pathway.

Colon Cancer

Cancer is a disease caused by cell cycle dysfunction. The ability to block the cell cycle progression in cancer cells can effectively elevate the anti-cancer potential of natural products (). A. muricata extracts, for example, were shown to have the potential to induce G1 cell cycle arrest (). The study also showed that treatments of HCT116 and HT-29 cells resulted in the up-regulation of the apoptotic pathway, as suggested by an increase in the production of ROS, an increase in detectable cytochrome c, and an increase in initiator and executioner caspases in both of the tested cell lines. Furthermore, an increase in the levels of Bax protein was also observed by flow cytometry, which further suggested the activation of the apoptotic pathway ().

Annona muricata Extracts in Conjunction with Conventional Treatment

Despite the various benefits associated with the use of A. muricata extracts in inhibiting cancer cell lines, their usage alongside chemotherapy and radiation therapy has not been explored in such experiments and is in need of immediate attention. However, one cell culture-based study revealed a promising outlook on the potential use of these plant extracts alongside current radiotherapy and chemotherapy methods. The study, conducted at Sebelas Maret University in Indonesia, revealed a synergistic interaction between A. muricataLinn leaves extracts with doxorubicin in reducing the development of Hela cells. In the study, 38.5 μg/ml polyketide derivatives isolated from the plant were shown to have a synergistic effect with every concentration of doxorubicin used during the treatment of Hela cells ().

What the National Cancer Institute says about Annonaceous acetogenins

Definition of Annonaceous acetogenins is from the National Cancer Institute’s website

The original text from the NCI defintion is below:

“A family of naturally occurring polyketides  that consist of C32 or C34 long chain fatty acids and combined with a propan-2-ol unit at C-2 to form a gamma-lactone which are isolated from various species of the plant family Annonaceae with potential antineoplastic and antimicrobial activity. Annonaceous acetogenins bind to the ubiquinone catalytic site(s) within the mitochondrial NADH:ubiquinone oxidoreductase (complex I), and block the electron transport chain in mitochondria. In addition, the acetogenins bind to and block the activity of ubiquinone-linked NADH oxidase, an enzyme overexpressed in the plasma membranes of cancer cells. This inhibits adenosine triphosphate (ATP) production, decreases intracellular ATP levels, and induces tumor cell apoptosis. Compared to normal cells, cancer cells have higher ATP demands. The Annonaceous acetogenins also inhibit microbial glucose dehydrogenase 6.”

Now for the average person that is a lot to digest, so let’s break it down even further:

A family of naturally occurring polyketides…

Polyketides are natural metabolites (byproducts in a chemical reaction that produces energy in a living thing) that comprise the basic chemical structure of various anticancer, antifungal, and anticholesteremic agents; antibiotics; parasiticides and immunomodulators. The sales of pharmaceuticals derived from polyketides routinely reaches $20 billion annually.

…that consist of C32 or C34 long chain fatty acids and combined with a propan-2-ol unit at C-2 to form a gamma-lactone…

  • C32 and C34 are two types of fatty acids. Fatty acids are common in food consumed by humans and animals because when eaten it provides energy to cells.
  • Propan-2-ol is a a type of alcohol.
  • So a fatty acid interacts with an alcohol to  produce

…which are isolated from various species of the plant family Annonaceae…

Annonaceae is a scientific classification term that refers to a plant family that has 2400 species, but is primarily known as the “custard apple” family.  The plant family is found primarily in tropical regions around the world. Within this family is Annona muricata, which is more commonly known in every English as soursop or graviola. In Spanish, it is known as guanabana.

…with potential antineoplastic and antimicrobial activity.

Antineoplastic activity: Activity that prevents, inhibits or halts the development of a tumor.

Antimicrobial activity: Activity that kills microorganisms or stops their growth. e.g. An antibiotics’ antimicrobial activity results in killing bacteria.

...Annonaceous acetogenins bind to the ubiquinone catalytic site(s) within the mitochondrial NADH:ubiquinone oxidoreductase (complex I) and block the electron transport chain in mitochondria.


In addition, the acetogenins bind to and block the activity of ubiquinone-linked NADH oxidase, an enzyme overexpressed in the plasma membranes of cancer cells.


This inhibits adenosine triphosphate (ATP) production, decreases intracellular ATP levels, and induces tumor cell apoptosis. Compared to normal cells, cancer cells have higher ATP demands. The Annonaceous acetogenins also inhibit microbial glucose dehydrogenase 6.