Soursop

Annona muricata is a species of the genus Annona of the custard apple tree family, Annonaceae, which has edible fruit.[4][5] The fruit is usually called soursop due to its slightly acidic taste when ripe. Annona muricata is native to the Caribbean and Central America but is now widely cultivated – and in some areas, becoming invasive – in tropical and subtropical climates throughout the world, such as India.[4][5]

The A. muricata fruit is generally called guanábana in Hispanic America, and the tree is a guanábano. Both tree and fruit were called catuche in some parts of Venezuela, but that word is currently less commonly used.

Annona muricata is also the main host plant for tailed jay (Graphium agamemnon) caterpillars. They eat the leaves voraciously and usually stick under the leaves to pupate.

Botanical drawing showing flower, leaves, and fruit

Annona muricata is a small, upright, evergreen tree that can grow to about 30 feet (9.1 m) tall.[4][5][8][9]

Its young branches are hairy.[9] Leaves are oblong to oval, 8 centimetres (3.1 in) to 16 centimetres (6.3 in) long and 3 centimetres (1.2 in) to 7 centimetres (2.8 in) wide. They are a glossy dark green with no hairs above, and paler and minutely hairy to no hairs below.[9] The leaf stalks are 4 millimetres (0.16 in) to 13 millimetres (0.51 in) long and without hairs.[9]

Flower stalks (peduncles) are 2 millimetres (0.079 in) to 5 millimetres (0.20 in) long and woody. They appear opposite from the leaves or as an extra from near the leaf stalk, each with one or two flowers, occasionally a third.[9] Stalks for the individual flowers (pedicels) are stout and woody, minutely hairy to hairless and 15 millimetres (0.59 in) to 20 millimetres (0.79 in) with small bractlets nearer to the base which are densely hairy.[9]

The petals are thick and yellowish. Outer petals meet at the edges without overlapping and are broadly ovate, 2.8 centimetres (1.1 in) to 3.3 centimetres (1.3 in) by 2.1 centimetres (0.83 in) to 2.5 centimetres (0.98 in), tapering to a point with a heart shaped base. They are evenly thick, and are covered with long, slender, soft hairs externally and matted finely with soft hairs within. Inner petals are oval shaped and overlap. They measure roughly 2.5 centimetres (0.98 in) to 2.8 centimetres (1.1 in) by 2 centimetres (0.79 in), and are sharply angled and tapering at the base. Margins are comparatively thin, with fine matted soft hairs on both sides. The receptacle is conical and hairy. The stamens are 4.5 millimetres (0.18 in) long and narrowly wedge-shaped. The connective-tip terminate abruptly and anther hollows are unequal. Sepals are quite thick and do not overlap. Carpels are linear and basally growing from one base. The ovaries are covered with dense reddish brown hairs, 1-ovuled, style short and stigma truncate.[9] Its pollen is shed as permanent tetrads.[10]

The fruits are dark green and prickly. They are ovoid and can be up to 30 centimetres (12 in) long,[9] with a moderately firm texture.[6] Their flesh is juicy, acidic, whitish[6] and aromatic.[9]

Annona muricata is tolerant of poor soil[6] and prefers lowland areas between the altitudes of 0 to 1,200 metres (3,900 ft). It cannot stand frost.[8][9] The exact origin is unknown; it is native to the tropical regions of the Americas and is widely propagated.[4][5][6] It is an introduced species on all temperate continents, especially in subtropical regions.[4][5]

The plant is grown for its 20–30 cm (7.9–11.8 in) long, prickly, green fruit, which can have a mass of up to 6.8 kg (15 lb),[5] making it probably the second biggest annona after the junglesop. Away from its native area, some limited production occurs as far north as southern Florida within USDA Zone 10; however, these are mostly garden plantings for local consumption. It is also grown in parts of China and Southeast Asia and is abundant on the Island of Mauritius. The main suppliers of the fruit are Mexico followed by Peru, Brazil, Ecuador, Guatemala, and Haiti.[11] 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.[12]

• Annona muricata var. borinquensis[3]

Raw soursop is 81% water, 17% carbohydrates, 1% protein, and has negligible fat (see table). In a 100 gram reference amount, the raw fruit supplies 276 kilojoules (66 kilocalories) of food energy, and contains only vitamin C as a significant amount (25%) of the daily value, with no other micronutrients in appreciable amounts (table).

The compound annonacin is contained in the fruit, seeds, and leaves of soursop.[15][16][17] The leaves of Annona muricata contain annonamine, which is an aporphine-class alkaloid containing a quaternary ammonium group.[18] The plant also contains lichexanthone, a compound in the xanthone class.[19]

Potential neurotoxicity

Annonacin, a neurotoxin found in soursop

The Memorial Sloan-Kettering Cancer Center cautions, "alkaloids extracted from graviola may cause neuronal dysfunction".[16] Annonacin has been shown in laboratory research to be neurotoxic.[16][17][20] In 2010, the French food safety agency, Agence française de sécurité sanitaire des produits de santé, concluded that "it is not possible to confirm that the observed cases of atypical Parkinson syndrome ... are linked to the consumption of Annona muricata".[21]

• Annona crassiflora
• Annona reticulata
• Asimina triloba
• Atemoya
• Cherimoya
• List of unproven and disproven cancer treatments
• Sugar-apple

Wikimedia Commons has media related to Annona muricata.

• Data related to Soursop at Wikispecies
• Soursop, List of Chemicals, Dr. James Duke, USDA Phytochemical and Ethnobotanical Databases, November 2004
• Morton, Julia F. (1987) Fruits of Warm Climates: Soursop