Vitellaria paradoxa, commonly known as the Shea tree, is a large deciduous tree native to West Africa. It is renowned for its seeds, which are the source of shea butter, a widely used natural fat. Shea butter is valued for its moisturizing, emollient, and therapeutic properties, making it a popular ingredient in skincare and cosmetic products.
Botanical Classification:
- Kingdom: Plantae
- Order: Sapindales
- Family: Sapotaceae
- Genus: Vitellaria
- Species: Vitellaria paradoxa
Plant Characteristics:
- Growth Form: The Shea tree can grow up to 15-20 meters (49-66 feet) in height and has a broad, spreading canopy. It features a dense, rounded crown and a trunk with a rough, greyish bark.
- Leaves: The leaves are leathery, ovate to elliptical, and dark green. They are typically 10-20 cm (4-8 inches) long and arranged alternately on the branches.
- Flowers: Shea trees produce small, fragrant flowers that are creamy white to pale yellow. These flowers are grouped in clusters and are relatively inconspicuous.
- Fruit: The fruit of the Shea tree is a green, fleshy drupe that turns yellowish-brown when ripe. It contains a single large seed, known as the shea nut, encased in a thick, fibrous shell.
Chemical Composition and Structure:
- Shea Butter:The primary product derived from the Shea tree is shea butter, which is extracted from the seeds of the fruit. Shea butter is composed of various fatty acids, including:
- Stearic Acid: Approximately 30-50%
- Oleic Acid: Approximately 40-60%
- Linoleic Acid: Approximately 3-10%
- Palmitic Acid: Approximately 4-8%
- Other Components: Shea butter also contains various triterpenes, phytosterols, and vitamins (A, E, and F) that contribute to its skin-nourishing properties.
How to Cultivate It:
- Soil: Shea trees thrive in well-drained, sandy loam soils. They are adapted to a range of soil types but prefer moderately fertile soil.
- Climate: The Shea tree requires a tropical climate with a distinct wet and dry season. It is adapted to regions with temperatures between 25-40°C (77-104°F) and can tolerate drought conditions.
- Watering: While the Shea tree is drought-resistant once established, it benefits from regular watering during the early stages of growth. During dry periods, supplemental irrigation may be necessary.
- Propagation: Shea trees are typically propagated from seeds. The seeds should be collected from mature, ripe fruits and sown in well-prepared nursery beds. The seedlings can be transplanted once they reach a suitable size.
Uses and Benefits:
- Skincare: Shea butter is widely used in skincare products for its moisturizing and emollient properties. It helps to soothe and hydrate the skin, improve elasticity, and reduce the appearance of scars and stretch marks.
- Haircare: Shea butter is also used in haircare products to condition and moisturize the hair and scalp. It helps to reduce dryness and improve the overall health and appearance of the hair.
- Medicinal Uses: Traditionally, Shea butter has been used in African medicine for its anti-inflammatory and healing properties. It is applied to treat minor burns, wounds, and skin irritations.
- Food: In some regions, Shea butter is used as a cooking fat and in traditional dishes.
Applications:
- Cosmetics and Personal Care: Shea butter is a common ingredient in lotions, creams, soaps, and lip balms. Its rich texture and moisturizing properties make it ideal for various cosmetic formulations.
- Pharmaceuticals: Due to its soothing and healing properties, Shea butter is used in topical treatments for skin conditions such as eczema and psoriasis.
- Food Industry: Although less common, shea butter is sometimes used in food products and confectionery in West Africa.
Environmental and Safety Considerations:
- Environmental Impact: The Shea tree is an important component of the African savannah ecosystem. Its cultivation can help prevent soil erosion and provide shade and habitat for wildlife. Sustainable harvesting and processing practices are essential to minimize environmental impact.
- Safety: Shea butter is generally safe for topical use and is well-tolerated by most skin types. However, individuals with nut allergies should exercise caution, as Shea butter is derived from a nut.
It is used in cosmetics, pharmaceuticals, baked goods, biodiesel and other fields.
Studies
It is mainly made up of fatty acids (1).
- 28-56% Stearic acid
- 34-61% Oleic acid
- Gallic acid
The trees that provide a higher content of these fatty acids are those from West Africa rather than from East Africa.
Medicine.
It is used in traditional medicine for the treatment of various diseases, including inflammation and fever. This is an ethyl acetate capable of exerting an anti-inflammatory and anti-rheumatoid action (2).
Two derivatives, glucosylcucurbic acid and methyl glucosylcucurbate, were recently isolated from the shea kernel. These and their derivatives of cucurbic acid and cucurbate methyl, were evaluated for their melanogenesis-inhibiting cancer properties (3).
For more information:
Shea butter studies
References_______________________________________________________________________
(1) Akihisa T, Kojima N, Katoh N, Ichimura Y, Suzuki H, Fukatsu M, Maranz S, Masters ET. Triterpene alcohol and fatty acid composition of shea nuts from seven African countries. J Oleo Sci. 2010;59(7):351-60. doi: 10.5650/jos.59.351.
Abstract. The content and composition of triterpene alcohol fractions of the non-saponifiable lipids (NSL) along with the fatty acid composition of the kernel fats (n-hexane extracts) of the shea tree (Vitellaria paradoxa; Sapotaceae) were determined for 36 samples from seven sub-Saharan countries: Cote d' Ivoire, Ghana, Nigeria, Cameroun, Chad, Sudan, and Uganda. The fat content of the kernels, proportion of NSL in the fats, and triterpene alcohols in the NSL are in the range of 30-54, 2-12, and 22-72%, respectively. The triterpene alcohol fractions contained alpha-amyrin (1), beta-amyrin (2), lupeol (3), and butyrospermol (4) as the major constituents along with minor or trace amounts of psi-taraxasterol (5), taraxasterol (6), parkeol (7), 24-methylene-24-dihydroparkeol (8), 24-methylenecycloartanol (9), dammaradienol (10), and 24-methylenedammarenol (11). Fatty acid composition is dominated by stearic (28-56%) and oleic (34-61%) acids. Shea butters from West African provenances contained in general higher levels of triterpene alcohols and stearic acid than those from East African provenances. Both stearic acid and total triterpene alcohol contents were significantly correlated to the latitude and elevation of the source population, indicating that higher levels of these compounds are found at higher ambient temperatures.
(2) Eyong KO, Foyet HS, Baïrys G, Ngosong Folefoc G, Acha Asongalem E, Lagojda A, Lamshöft M. A new ursane triterpenoic acid and other potential anti-inflammatory and anti-arthritic constituents from EtOAc extracts of Vitellaria paradoxa stem bark. J Ethnopharmacol. 2015 Nov 4;174:277-86. doi: 10.1016/j.jep.2015.08.014.
(3) Zhang J, Kurita M, Ebina K, Ukiya M, Tokuda H, Yasukawa K, Masters ET, Shimizu N, Akihisa M, Feng F, Akihisa T. Melanogenesis-inhibitory activity and cancer chemopreventive effect of glucosylcucurbic acid from shea (Vitellaria paradoxa) kernels. Chem Biodivers. 2015 Apr;12(4):547-58. doi: 10.1002/cbdv.201400424.
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Zhang J, Kurita M, Shinozaki T, Ukiya M, Yasukawa K, Shimizu N, Tokuda H, Masters ET, Akihisa M, Akihisa T. Triterpene glycosides and other polar constituents of shea (Vitellaria paradoxa) kernels and their bioactivities. Phytochemistry. 2014 Dec;108:157-70. doi: 10.1016/j.phytochem.2014.09.017.