 Dacryodes edulis is an evergreen tree attaining a height of 18–40 m
in the forest but not exceeding 12 m in plantations. It has a
relatively short trunk and a deep, dense crown. The bark is pale
gray and rough with droplets of resin. The leaves are a compound
with 5-8 pairs of leaflets. The upper surface of the leaves is
glossy. The flowers are yellow and about 5 mm across. They are
arranged in a large inflorescence. The fruit is an ellipsoidal drupe
which varies in in length from 4 to 12 cm. The skin of the fruit is
dark blue or violet, whereas the flesh is pale to light green. The
tree flowers at the beginning of the rainy season and bears fruits
during 2 to 5 months after flowering. There are two variants of Dacryodes edulis: D. e. var. edulis and D. e. var. parvicarpa. The
fruit of D. e. var. edulis is larger and the tree has stout,
ascending branches. D. e. var. parvicarpa has smaller fruit and
slender, drooping branches.
Habitat and range
The preferential habitat of D. edulis is a shady, humid tropical
forest. However, it adapts well to variations in soil type,
humidity, temperature and day length. The natural range extends from
Angola in the South, Nigeria in the North, Sierra Leone in the West
and Uganda in the East. It is also cultivated in Malaysia.
Oil composition from fruits of two cultivars of African pear in
Cameroon
The oil of fruits of D. edulis is a rich source of amino acids
and triglycerides [triacylglycerols]. The fatty acid compositions of
fruit pulp oil of 2 cultivars of D. edulis (cultivars 1 and 2, grown
in Cameroon) were determined. Fruits significantly differed in mass,
length, thickness of pulp and mass of kernel, but contained similar
amounts of oil (64.7 and 62% in cultivars 1 and 2, respectively,
with ratios of oil:fruit of 1.4 and 1.54, respectively). The fatty
acids (palmitic, oleic, stearic, linolenic and linoleic acids) and
triglycerides compositions of oils of both cultivars were similar
(although cultivar 1 was richer in palmitolino-olein (18.5 compared
with 14.1%) and cultivar 2 was richer in dipalmito-olein (24.6
compared with 16.2%)).[1]
Nutritional and commercial importance
A traditional food plant in Africa, this little-known fruit has
potential to improve nutrition, boost food security, foster rural
development and support sustainable landcare.
The main use of D. edulis is its fruit, which can be eaten either
raw, cooked in salt water or roasted. Cooked flesh of the fruit has
a texture similar to butter. The pulp contains 48% oil and a
plantation can produce 7-8 tons of oil per hectare. It is also rich
in vitamins. The kernel can be used as fodder for sheep or goats.
The flowers are useful in apiculture. Shade tolerant traditional
crops, such as Xanthosoma sagittifolium and taro can be
co-cultivated with D. edulis.
The wood of D. edulis is elastic, greyish-white to pinkish. The
wood has general use for tool handles, and occasionally for mortars,
and is suitable for carpentry. The resin is sometimes burnt for
lighting or used as a glue. The tree is used as an ornamental plant
and is known to improve soil quality by providing large quantities
of biomass. The tree is also a source of many traditional medicines.
Medicinal Uses
The plant has long been used in the traditional medicine of some
African countries to treat various ailments such as wound, skin
diseases, dysentery and fever.
The extracts and secondary metabolites have been found to show
biological activities such as antimicrobial, antioxidant and anti
sickle-cell disease.
A wide range of chemical constituents such as terpenes,
flavonoids, tannins, alkaloids and saponins have been isolated from
the plant.
Nomenclature
The name of the genus comes from the Greek word for tear, dakruon.
This is a reference to the resin droplets on bark surface of its
members. |
