- Enterolobium cyclocarpum (Jacq.) Griseb. is a spectacular looking tree with its huge, spreading, and spherical crown.
- The tree is a distinctive feature of many Central American landscape.
Enterolobium has been adapted as the national tree of Costa Rica. (10)
- Most of the common names refer to its distinctive, thickened, contorted, indehiscent pods which resemble an ear. Other common names are: ear fruit, ear pod, orejoni (from Spanish oreja, an ear) and guanacaste (conacaste, a Nahuatl derivation signifying an ear tree.
- An average adult tree produces an average of 2000 pods, each with 10-16 seeds (900-1200/kg)
Enterolobium cyclocarpum is a medium-sized to large evergreen or briefly deciduous tree, growing 25 to 35 meters tall, with a trunk up to 3.5 meters in diameter.
Canopy is wide.
Bark is light gray with prominent dark-reddish brown vertical fissures. Fissures are closer together in young trees. Crown is broad and widely spreading. Leaves are alternate, bipinnate compound, 15 to 40 centimeters long and 17 centimeters wide, with a petiole 2 to 6 centimeters long bearing 4 to 15 pairs of pinnae, each pinna with 40 to 70 leaflets. Leaflets are slender oblong, 8 to 15 millimeters long by 2 to 4 millimeters wide. Inflorescences are globular, 3 centimeters in the axils of new leaves, supported by a long pedestal, each spherical white head composed of about 50 individual flowers,with thousands of thin, filamentousstamens. Each blossom consists of about 20 stamens and a single pistil, bound by a short tubular corolla and shorter calyx. Flowers are very fragrant. Fruits are large, 7 to 12 centimeters in diameter, glossy dark brown, kidney- or ear-shaped, curved into an overlapping circle. Each pod contains 8 to 20 radially arranged seeds, 14 to 17 millimeters long, 8 to 11 millimeters wide, and 6 to 7 millimeters thick. Flesh is sweet. Seeds are brown with a light brown or orange ring, hard and stone-like. (2)
- Ornamental cultivation.
- The wide spreading canopy makes it an ideal shade tree.
- Native to tropical regions of the Americas, Mexico, Brazil, and Venezuela.
- Oil contains high proportions of linoleic and oleic acid, as well s palmitic and linolenic acid.
- Polysaccharide contains galactose, arabinose, glucuronic acid and its 4-0-methyl derivative. (see study below)
- D-(+)-pinitol, was purified for the first time from an aqueous extract of the heartwood of Enterolobium cyclocarpum and its chemical structure determined. (see study below) (6)
- Aqueous extract of heartwood by gas chromatography yielded two major chemical groups viz. monoterpenes (46.5%) and phenols (18.7%). Fifty-seven constituents, including D-limonene, terpineol and eugenol were identified. (see study below)
Study has shown anticancer, antiproliferative properties.
- The immature pods are eaten as cooked vegetable.
- Seeds are toasted.
- No known folkloric medicinal use in the Philippines.
In Mexico, sap used for flu and bronchitis; the astringent green fruit is used for diarrhea.
- Gum from the trunk used tor treatment of chest afflictions.
- In the Caribbean, Central and South America, aerial parts used for treatment of bronchitis and sore throat. Toxicity reported as severe diarrhea, abdominal pain. (9)
- Fodder: Foliage, fruits and seeds provide fodder for cattle, pigs, goats sheep and horses.(2) Study has shown that leaves can be used as partial substitute of lucerne in diets for growing goats, without affecting animal performance. (7) It yields large quantities of palatable and nutritious pods containing a sugary dry pulp. (10)
- Wood: reddish-brown, lightweight and water resistant. Used for making doors, windows, furniture.
Because of its durability in water, it was used for making water troughs and dug-out canoes.
- Seeds: In Costa Rica, seeds are used to make jewelry. In Panama, ripe seeds are heated in the fire until they pop like pop-corn. (2)
- Tannins: Fruit and bark yield tannins, used for leather curing and soap manufacturing. (2)
- Sap: Used as natural adhesive. (2)
• Anticancer / Antiproliferative / Leaves: Study evaluated the cytotoxicity of methanolic extract of leaves. In brine shrimp lethality assay, The ME showed cytotoxic activity with LC50 of 31.63 µg/mL. For HeLa and MCF7, significant growth inhibition was observed with IC50 of 2.07 ± 1.30 µg/mL and 11.84 ± 1.18 µg/mL, respectively. Cell cycle analysis showed arrest in G2/M phase for HeLa, and arrest in G1/G0 phase for MCF7 cells. Annexin V-FITC/PI assay revealed phosphatidylserine translocation in both cell lines, suggesting apoptosis induction. Results demonstrated potential antiproliferative activity lending support to traditional claims. (3)
• Nutritive Value / Leaf, Seed, Pod, and Fruit: Comparative study evaluated the nutritive value of leaf, seed, pod, and fruit by proximate, secondary metabolites and in vitro gas production. Proximate analysis showed all samples were high in crude protein (10.4 to 21.7%), ether extract (10.0 to 11.2%), and low in crude fiber (39.8 to 63.5%).. All samples yielded saponin; medium in the leaf, negligible in others. All yielded steroids; none yielded phenol. Browse parts had sufficient phosphorus, calcium, magnesium, potassium, iron and copper to meet ruminant requirements. The leaf showed more saponin that other parts, leading to low in-vitro gas production parameters, suggesting low acceptability to livestock. Results showed seeds, pod, and whole fruit had nutritive value, with potential as supplements for ruminants. (4)
• Gum: Tree easily exudes a gum, three days after an incision is made at trunk level. Average yield is very high (36 g/specimen/week). Gum has high solubility, which increases if the gum is collected as soon as exuded. Analytical data on the gum showed a limiting viscosity number (100mLg-1). The functionality of the gum as stabilizing agent for emulsions has been demonstrated(see constituents above) (5)
• D-(+)-Pinitol / Heartwood / Insecticidal Potential: D-(+)-Pinitol, a natural product of the group of cyclitols, was purified for the first time from an aqueous extract of heartwood of Enterolobium cyclocarpum. D-(+)-pinitol has been isolated from several plants and its effect on glucose metabolism is well known (Narayana et al, 1987). Insecticidal activity of this cyclitol on larval growth of Heliotis zea, Aedes aegypti and Culex quinquefasciatus has been described. (6)
• Anti-Termite / Heartwood: Heartwood aqueous extracts from E. cyclocarpus exhibited toxic effect against Incisitermes marginipennis (Latreille) with more than 60% mortality at concentration of 56.63 mg. Feeding rate correlated positively with mortality of termites. Study yielded 57 constituents, including D-limonene, terpineol and eugenol. These terpenes have repellent activity against insects. (see constituents above) (8)
- Seeds in the cybermarket.