Agriculture Reference
In-Depth Information
This unique structure in the palm oil triglyceride backbone therefore ensures that the UFAs in the
sn-2 position are mostly absorbed from the intestine and that the saturated fatty acids in the sn-1
and sn-3 positions ensure stability and protection against oxidation. In addition, it contains, among
other things, glycerides of fatty acids with high molecular weights, including oleic acid (40-50%)
and myristic acid (1-5%). The oil is rich in carotenoids (including vitamin A and β-carotene) and
sterols. Raw unprocessed palm oil normally contains 500-700 ppm carotenoids, of which 35% is α-
and 56% is β-carotene. The refined red palm olein, however, contains 513 ppm carotene, of which
44% is α- and 33.3% is β-carotene. Red palm oil contains high levels of provitamin E (600-1000
ppm), with 78-82% being tocotrienols and 18-22% tocopherols.
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It also elaborates the following
phytonutrients: sterols (60-620 ppm), squalene (200-500 ppm), coenzyme Q10 (10-80 ppm), gly-
colipids (1000-3000 ppm), and triterpene alcohol (40-80 ppm). The kernel yields an oil (PKO) that
is pale yellow to colorless and comprised of the following glycerides of fatty acid: lauric acid (50%
of total fatty acids), myristic acid (15% of total fatty acids), oleic acid (15% of total fatty acids), and
traces of linoleic acid and stearic acid.
Pharmacological Studies —
Natural carotenes obtained from palm oil have been shown to
suppress the promoting stage of two-stage carcinogenesis of mouse skin and also inhibit the pro-
liferation of human malignant tumor cells, such as neuroblastoma GOTO cells, stomach cancer
HGC-27 cells, and pancreatic cancer PANC-1 cells.
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The bright red nonsolid palm oil has strong
antioxidant activity. Tocotrienols found in red palm oil are 40-60 times more potent than tocopher-
ols as antioxidants. Red palm oil also has the highest content of tocotrienols of all edible oils, with
rich bran oil as the only other edible oil that comes close, with just less than a third of the levels
contained in red palm oil.
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The extract of the leaves has been evaluated for possible antioxidant activities by 2,2-diphenyl-
β-picrylhydrazyl free radical scavenging activity (DPPH), xanthine oxidase inhibition (XOI), nitric
oxide scavenging activity (NOS), and hydrogen peroxide scavenging activity (HPSA) assays. It was
found that the extract exhibited antioxidant activity with an IC
50
value of 814 g/mL in the DPPH
radical scavenging method, 534.04 µg/mL in the NOS assay, 37.48 µg/mL in XOI, and 1052.02 µg/
mL by the HPSA method based on the concentrations tested.
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PKO obtained from the seeds is used as a lubricant and emollient for damaged skin and as a
suppository base. The soap prepared from the palm husk ash possesses antimicrobial properties.
EMBELIA SCHIMPERI
Botanical Name —
Embelia schimperi
Vat ke
Synonyms —
E. abyssinica
Bak.,
Pattara pellucida
Hiern
Family —
Primulaceae
African Names —
Kiru: gezi, Masai: os sumategi; Zulu: ibinini
Description —
The plant is a climber with rough stems and conical protuberances. The fruits
occur as globular, reddish-brown berries, with a small projection at the apex.
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Ethnomedicinal Uses —
The leaves are used as a food vegetable in East Africa, especially in
Uganda. A decoction of the stem bark is used in Nigeria as an antispasmodic. The fruit is used by
the Masai and Chagga as an anthelmintic. A related species,
E. kraussi
Harv., is used by the Zulu
as a taeniacide
.
In East Africa, both the roots and stem bark are used for the same purpose. Watt
and Breyer-Brandwijk indicated that various species of the genus are employed as an anthelmin-
tic, and the berries are articles of commerce in markets in many parts of the region.
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The Asian
species
E. ribes
has long been used in Indian medicine as a carminative, anthelmintic, stimulant,
and alterative.
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Constituents —
It contains about 6-7% of the active component embelin (2,5-dihydroxy-
3-lauryl-
p
-benzoquinone) and also several naphthaquinones, resinoids, tannins, and an alkaloid
