Traditional oil palm (Elaeis guineensis jacq.) and its medicinal uses: A review

Abstract

The oil palm (Elaeis guineensis Jacq.) has been reported to originate along the gulf of the guinea in West Africa. The various parts of the tree have been used locally and traditionally for various medicinal purposes. Some of these uses have been proved by scientific experiments. Palm oil is extracted from the mesocarp of the fruit and is used traditionally for the treatment of headaches, pains, rheumatism, cardiovascular diseases, arterial thrombosis and an atherosclerosis due to its rich phytonutrients. The leaves are also used for the treatment of cancer, cardiovascular diseases, kidney diseases and wound healing. The sap also has been found to be rich in phytonutrients that can be used to treat various diseases. This review therefore seeks to explore many of the uses of the oil palm using the various parts of the oil palm.

Full text

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Review
Traditional oil palm (Elaeis guineensis jacq.) and its medicinal uses: A review
Bamidele Victor Owoyele1,*, Gbenga Opeyemi Owolabi2
1
Department of Physiology,University of Ilorin, P.M.B. 1515, Ilorin, Nigeria;
2
Department of Physiology, Ladoke Akintola University
of Technology, Ogbomoso, Nigeria
ABSTRACT
The oil palm (Elaeis guineensis Jacq.) has been reported to originate along the gulf of the guinea in West
Africa. The various parts of the tree have been used locally and traditionally for various medicinal
purposes. Some of these uses have been proved by scientific experiments. Palm oil is extracted from the
mesocarp of the fruit and is used traditionally for the treatment of headaches, pains, rheumatism,
cardiovascular diseases, arterial thrombosis and an atherosclerosis due to its rich phytonutrients. The
leaves are also used for the treatment of cancer, cardiovascular diseases, kidney diseases and wound
healing. The sap also has been found to be rich in phytonutrients that can be used to treat various diseases.
This review therefore seeks to explore many of the uses of the oil palm using the various parts of the oil
palm.
Keywords anti-inflammatory, anti-cancer, cardiovascular diseases, Elaeis guineensis, medicinal uses, oil
palm, rheumatism
INTRODUCTION
It is generally agreed that the oil palm (Elaeis guineensis Jacq.)
originated from the equatorial tropical rain forest region of
Africa, precisely along the gulf of guinea (Naher et al., 2013).
It exists in the wild type and cultivated state. It was first
introduced to Brazil and other tropical countries in the 15
th
century by the Portuguese (Corley, 1976). The oil palm fruit is
a drupe. The American oil palm, Elaeis oleifera is native to
tropical Central America and South America.
This review intends to provide information on the
documented medicinal uses of oil palm including laboratory
studies on the plant. Earlier review by Obahiagbon (2012) was
limited to an aspect of the plant. This present review covers
both the traditional as well as the scientific uses of the oil. The
review however does not extend to the core botanical aspect of
the plant. The literatures used for this review were obtained
from Medline and Google Scholar search carried out from
September, 2013 to April, 2014.
The traditional theory about the uses of oil palm in many
parts of Nigeria is that products from oil palm are antidotes that
can be used in the treatment of many ailments especially
gastrointestinal disorders and poisons.
Oil palm
The African oil palm (Elaeis guineensis Jacquin) produces two
different kinds of oil namely, palm oil and palm kernel oil
(Ekwenye and Ijeomah, 2005). The pericarp consists of three
layers: the exocarp (skin), mesocarp (outer pulp containing
palm oil), and the endocarp (a hard shell enclosing the kernel or
endosperm, which contains oil known as kernel oil) (Naher et
al., 2013). Palm oil is extracted from fleshy mesocarp of the
fruit either by milling mechanically or by the traditional
method (Hartley, 1977; Edem and Akpanabiatu, 2006), which
contains 45 - 55% oil, but varies from light yellow to orange-
red in color, and melts at 25C (Duke, 1983). The oil colour is
determined by the carotenoids (Cottrell, 1991). The major
carotenoids found in palm oil are the beta-carotene
(Obahiagbon, 2012). Palm kernel oil is obtained from the
kernels enclosed in the endocarp (Ekwenye and Ijeomah, 2005).
Palm oil contains saturated palmitic acid, oleic and linoleic acid,
giving it a higher unsaturated acid content than palm kernel or
coconut oils (Duke, 1983; Edem, 2002). Along with coconut oil,
palm oil is one of the few highly saturated vegetable fats. It is
semi-solid at room temperature and contains several saturated
and unsaturated fats in the forms of glyceryl laurate (0.1%,
saturated), myristate (1%, saturated), palmitate (44%, satur
ated), stearate (5%, saturated), oleate (39%, monounsaturated),
linoleate (10%, polyunsaturated), and alpha-linolenate (0.3%,
polyunsaturated) (Cottrell, 1991). Palm oil also has minor
constituents including phospholipids (Goh et al., 1983).
Currently, palm oil is the world largest edible oil (Naher et al.,
2013) and is the main source of domestic or edible oil in Africa
(Obahiagbon, 2012; Oluba et al., 2009). As much as palm oil
provides energy and fatty acid needs (Oguntibeju et al., 2009),
much of the palm oil that is consumed as food is to some
degree oxidized rather than in the fresh state, and this oxidation
appears to be responsible for the health risk associated with
consuming palm oil (Edem, 2002).
Ekwenye and Ijeomah (2005) reported that traditionally,
palm oil has been used in the South Eastern Nigeria for the
treatment of various diseases and skin infections. This was
confirmed by their experiment carried out at the Michael
Okpara University of Agriculture, Umudike, Abia State,
Nigeria using five microorganisms namely; Staphylococcus
aureus, Escherichia coli, Pseudomonas areuginosa, Candida
albicans, and Aspergillus niger known to cause some infections
treatable with palm oil and palm kernel oil. In this experiment,
*
Correspondence: Bamidele Victor Owoyele
E-mail: deleyele@yahoo.com or owoyele@unilorin.edu.ng
Received January 11, 2014; Accepted May 20, 2014; Published
August 31, 2014
doi: http://dx.doi.org/10.5667/tang.2014.0004
©2014 by Association of Humanitas Medicine
This is an open access article under the CC BY-NC license.
(http://creativecommons.org/licenses/by-nc/3.0/)

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0.04 ml of 100% concentration palm oil and palm kernel oil
extracts was impregnated into the sterilized discs according to
the method of Ekpa and Ebana (1996). The anti-microbial test
was done using the disc diffusion method of Brauer et al. (1996)
was adapted using nutrient agar, sabouraud dextrose agar, and
the impregnated discs. Palm oil has also been reported to be
anodyne, anti-dotal, aphrodisiac and a diuretic (Irvin, 1985;
Sasidharan et al., 2012). It is folk remedy for headaches, pains,
rheumatism, cardiovascular diseases, arterial thrombosis and an
atherosclerosis (Ekwenye and Ijeomah, 2005; Honstra, 1986;
Irvin, 1985; Sasidharan et al., 2012). The palm oil is known to
be effective against many forms of intestinal disorders,
especially diarrhoea and dysentery in infants (Ekpa and Ebana,
1996.). The fruit mesocarp oil and palm kernel oil are
administered as poison anti-dote and used externally with
several other herbs as lotion for skin diseases. Palm kernel oil
is applied to convulsing children to regulate their body
temperature. Folk remedies of oil palm also include treatment
for cancer and liniment (Irvin, 1985; Sasidharan et al., 2012).
Anti-oxidant activity
Palm oil provides a rich source of beta-carotene and vitamin E,
namely tocopherols and tocotrienols which are recognized
nutritional anti-oxidants that act as scavengers of the oxygen
atom or free radicals (Chong and Ng, 1991; Ekwenye and
Ijeomah, 2005; Goh et al., 1985). The oxygen atom or free
radicals can arise during the body’s normal oxidative
metabolism or from the action of toxic pollutants that
contaminate our food and have been implicated in ageing, heart
disease and cancer (Ekwenye and Ijeomah, 2005). E.
guineensis is also used as a wound healing agent among the
natives of Africans and as therapeutic agent in other parts of the
World (Sasidharan et al., 2010; Sasidharan and Vijayarathna,
2012). The palm oil is also used for biofuels and some
manufactured products (Naher et al., 2013). Carotenoids are
potent anti-oxidants. Packer et al. (1992) showed that alpha-
carotene is a more potent anti-oxidant than beta-carotene. Red
palm oil is rich in natural phytonutrients that are important for
health. These phytonutrients (i.e. tocotrienols and carotenes)
are also powerful anti-oxidants that help maintain the stability
of the oil during cooking process and may extend the shelf life
of food prepared with red palm oil
Research has shown that consumption of red palm oil
significantly enhanced vitamin A levels in humans, and it is
beneficial in preventing vitamin A deficiency (Manorama and
Rukmini, 1991; Roo, 2000; Solomons, 1998) and it is used for
combating vitamin A deficiency in developing countries
(Rukmini, 1994). Additionally, some workers have advised that
nursing mothers should take red palm oil as supplement with
their food in order to prevent vitamin A deficiency (Lietz et al.,
2000). Vitamin A deficiency may lead to blindness, skin disease
and weakened immune function. The vitamin A content of the
red palm oil plays important roles in growth, development and
in visual process (Edem, 2009). The human body is able to
convert provitamin-A carotenoids (alpha- and beta-carotene)
when there is a deficiency, hence it is safer to supplement with
carotenes than consuming vitamin A (retinoids) directly.
Excessive consumption of retinoids may lead to toxicity with
symptoms ranging from mild, such as headache, nausea and dry,
itchy skin to severe, such as liver damage (Solomons, 1998).
Tocotrienols are members of the vitamin E family. In the
body, vitamin E acts as an anti-oxidant that protects lipid from
peroxidation and help quench free radicals. However, there is a
difference in anti-oxidant potency between tocotrienol and its
sibling tocopherol. Tocotrienol has been shown to be 40 to 60
times more potent than tocopherol as an anti-oxidant. Palm oil
is the only vegetable oil available on the world market that
naturally contains tocotrienols (Cottrell, 1991; Ebong et al.,
1999; Elson, 1992; Van Rooyen et al., 2008) and is the richest
natural source of beta - carotene (500 - 700 mg/l) which is
responsible for the characteristic colour of the oil. Similar to
the tocopherols, tocotrienols consist of 4 members: alpha, beta,
gamma, and delta isomers (Serbinova, 1991). Alpha toco
pherols and gamma tocotrienols have anti-oxidative effects on
lipid peroxidation, in the presence of a xenobiotic metabolizing
enzyme that induces lipid peroxidation (Zuzana et al., 2005).
The vitamin E, particularly the tocotrienol present in palm oil
can suppress the synthesis of cholesterol in the liver (Mcintosh
et al., 1991; Qureshi et al., 1991; Qureshi et al., 1980). Some
scientists in South Africa have been able to establish that
oxidative stress plays a role in inflammatory and chronic
disease such as HIV/AIDS and TB and contribute significantly
to depletion of immune factors, micronutrients and progression
of disease and that red palm oil could potentially retard the
process because of rich anti-oxidants (Oguntibeju et al., 2009).
Anti-diabetic action
Studies have indicated that the potential mechanism of action
for the improvement in glucose metabolism with E. guineensis
involves inhibition of the enzyme dipeptidyl peptidase-4 (DPP-
4; Abdullah, 2009) the effect of which is to prevent degradation
of gastric inhibitory polypeptide, which itself stimulates insulin
secretion, suppresses glucagon secretion and slows gastric
emptying. E. guineensis is rich in catechins and polyphenols
(Jaffri, 2011). Prior studies in streptozotocin-induced hyper
glycemic rats showed that E. guineensis improved proteinuria
and reduced oxidative stress levels (Rosalina Tan, 2011;
Yamabe, 2006). This suggests a potential benefit for the pre-
diabetic and diabetic states. Administration of tocopherol,
Vitamin E or tocotrienol-rich fractions of palm oil, have been
shown to recover glycemic status, inhibit oxidative damage;
prevent DNA damage in animal studies and prevent
glycosylation of end-products in serum and decrease in diabetic
rats (Budin et al., 2006; Nazaimoon and Khalid, 2002;
Obahiagbon, 2012)
Cardiovascular activities
Peer review journals have documented palm tocotrienol
complex’s promising hypocholesterolemic properties (Qureshi
et al., 1991, 1995). Also, the daily consumption of tocotrienols-
enriched fraction of palm oil (200 mg palmvitee capsule) can
result in a significant reduction of serum cholesterol, Low
Density Lipoprotein cholesterol, APOB, thromboxane, platelet
factor 4 and glucose of hyper cholesterolemic subjects within
four weeks of administration (Qureshi et al., 1991; Packer,
1992; Song and DeBose-Boyd, 2006). A number of human
feeding studies reported that palm oil diets showed a reduction
of blood cholesterol values ranging from 7 to 38% (Mattson
and Grundy, 1985; Bonanome and Grundy, 1988). A
comparative study in young Australian adults showed that the
total blood cholesterol, triglycerides and High Density
Lipoprotein (HDL) - cholesterol levels of those fed on palm oil
(palm olein) and olive oil were lower than those fed on the
usual Australian diet (Choudhury et al., 1995). A number of
studies have also shown that palm oil increased HDL
cholesterol and Apo A-1 levels (Sundram et al., 1992; Truswell
et al., 1992). Other studies have also shown the beneficial
effects of palm oil on the cholesterol level of the body
(Marzuki et al., 1991; Ng et al., 1992, 1991; Zhang et al., 1997).
The position of the saturated and unsaturated fatty acid chains
in a triglyceride backbone of palm oil molecule determines
whether the fat will elevate cholesterol level in the blood

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(Kritchevsky, 1988, 1996). High blood pressure or
hypertension is one of the major risk factors of cardiovascular
diseases and strokes. In a human clinical trial, patients
supplemented with palm tocotrienol complex for two months
resulted in significant reduction in aortic systolic blood
pressure (Rasool et al., 2006). In an earlier review by
Obahiagbon (2012), he pointed out that Tocotrienol-rich
Fraction (TRF) of palm oil exhibited cardio-protective ability
in animal trials (Das et al., 2008). The cardio-protective effects
produced by the isomers of tocotrienol were of the order of: γ >
α >δ. The inhibition of normal cellular gene, C-Src activation
and proteosome stabilization were found to be reasons behind
the cardio-protective properties of TRF (Das et al., 2008).
Feeding experiments using various animal models have
highlighted that red palm oil is beneficial to health by reducing
oxidative stress (Ebong et al., 1999). Many studies have
demonstrated the protective effects of red palm oil in an
ischemia/reperfusion model of oxidative stress (Bester et al.,
2006; Engelbrecht et al., 2006; Esterhuyse et al., 2005)
Palm oil has been shown to possess anti-clotting effect and
it prevents the formation of thrombus in the blood vessels
(Oguntibeju et al, 2010). A human study (Kooyenga et al., 1997)
showed that tocotrienol (from palm oil) supplementation can
reduce stenosis of patients with carotid atherosclerosis. Vitamin
E in palm oil has been linked with inhibition of platelets from
sticking to each other. Other reports showed that palm oil diets
increases the production of prostacyclin or thromboxane (Ng et
al., 1992; Sundram et al., 1990). Thus scientific evidence
indicates that the palm oil diet is anti-thrombotic. Studies in
animals confirmed that palm oil do not promote the formation
of plaques in the arteries. A study was conducted on rabbits to
test the effect of palm oil on atherosclerosis. After feeding the
rabbits for one and a half years, palm oil and sunflower oil diets
caused the lowest degree of atherosclerosis in comparison with
fish oil, linseed oil and olive oil. Similarly, the effects of palm
oil was also compared with other types of plants derived oils
and at the end of the 14-month feeding period, coconut oil fed
rabbits had the most atherosclerosis lesions, while in palm oil-
fed rabbits; the number of lesions was no different from that
with the other oils (Oguntibeju et al., 2010).
Anti-bacterial
The anti-bacterial activity of this plant extract against different
micro-organisms and anti-oxidant activity have already been
reported (Manjunatha, 2005; Sasidharan et al., 2009). Moreover,
Chong together with Sasidharan and some others (Chong et al.,
2008) described the potential of E. guineensis leaf methanol
extract as an infected wound healing agents. They observed that
the bacterial count in the E. guineensis extract treated rats was
significantly reduced to 102 CFU/g tissues on day 16. In a
further study, Sasidharan tested wound healing activity without
infection and the expression of matrix metalloproteinases
(Sasidharan et al., 2012).
Toxicity
Several studies have been conducted to confirm the non-
toxicity of different parts of E.guineensis at normal doses
(Rajoo et al., 2010; Syahmi et al., 2010). Syahmi et al. (2010)
evaluated the acute oral toxicity of methanol extract of the
leaves using a dose of 5g and found no toxicity. They also use
the brine shrimp bioassay and also reported no toxicity. Also,
Anyanji et al. (2013) showed that the ethanol extract of the
palm leaves do not cause any toxicity at 2 g/kg but it appears
toxic at 5 g/kg based on a single administration after seven days.
However, the indices of toxicity were partially reversed after 14
days of administration.
Conservation and preservation
Several literature have reported the use of palm oil in
preservation purposes from various parasites including cowpea
weevil, Callosobruchus maculatus (Law-Ogbomo and
Egharevba, 2006), Sitophilus zeamais and Callosobruchus
maculates (Abulude et al., 2007).
Anti-cancer action
Studies have shown that tocotrienols fractions of palm oil were
able to induce an inhibitory action on the human breast cancer
cells, whereas the alpha-tocopherols were not able (Nesaretnam
et al., 2004, 2008; McIntyre et al., 2000). Palm oil has been
reported to be with wide range of protective properties against
disease, aging as well as being modulators for cellular
processes / functions where photo oxidative processes
predominate by acting as scavengers of oxygen and peroxyl
radicals (Van Rooyen et al., 2008). It has been shown that fresh
palm oil has no adverse effect on body weight and morphology
of body tissues, lowers the level of serum lipids and inhibits
tumour growth (Kritchevsky, 2000), enhances intestinal uptake
of protein and the metabolism of sulphur-amino acids and
promotes reproductive capacity (Ebong et al., 1999). Several
researches have been conducted on cancer with the view to
finding a lasting solution to the disease. Sundram and his
colleagues (1989) were able to conduct an experiment to show
that RPO significantly reduce tumor incidence in some
experimental rats compared with the control groups. RPO,
when compared with saturated fats and oils, may help fight
cancer, especially breast cancer (Nesaretnam, et al., 1992). This
may be due to tocotrienols (Nesaretnam, 1998: Elson, 1992) or
other phytonutrients (Guthrie et al., 1997) present in palm oil.
Indeed, Professors K. K. Carroll of the Centre for Human
Nutrition at the University of Western Ontario and David
Kritchevsky of the Wistar Institute recently concluded that
evidence from animal and in vitro studies indicate that
tocotrienols of palm oil are effective anti-cancer agents and
provide adequate justification for clinical trials in human
cancer patients (Nesaretnam, 1998). This oil has equally been
shown to reduce the incidence of azoxymethane-induced
aberrant crypt foci in rats and may therefore have a beneficial
effect in reducing the incidence of colon cancer (Boateng et al.,
2006).
Anti-inflammatory effects
The TRF of palm oil has been shown by Wu et al. (2008) to
possess anti-inflammatory activities in a study involving the
injection of lipopolysaccharide-induced inflammatory response.
The mediators of cellular inflammation such as nitric oxide
(NO), prostaglandin E2, and transcription of pro inflammatory
cytokines were significantly reduced. The following were
equally blocked; inducible NO, cyclooxygenase 2 expression
and NF-kappa B expression.
Leaves of palm oil
A review of the health benefits of the leaf extracts of oil palm
has been provided extensively by Mohammed (2014), however,
the present review is to provide additional information.
Anti-cancer activities
Methanolic oil palm (Elaeis guineensis) leaf extract is rich in
polyphenols (Runnie et al., 2003; Jaffri, 2011).The methanolic
leaf extract of E. guineensis has also been shown to possess
anti-cancer activities (Sasidharan and Vijayarathna, 2012).
Studies have observed the presence of a large number of
bioactive compounds in the methanolic extracts of this plant

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including tannins, alkaloids, steroids, saponins, terpenoids, and
flavonoids which exhibit various biological activities
(Sasidharan et al., 2010; Gulecha and Sivakuma, 2011; Kumar
et al., 2011). These compounds are present in a number of food
items and hold great potential as drug candidates due to their
safety, low toxicity and wide acceptance amongst the public.
Wound healing
Sasidharan et al. (2012) reported in their article that in
traditional medicine, the leaf of E. guineensis is squeezed and
the juice that is obtained is placed on wounds to promote
healing (Irvin, 1985). They tried to establish this in an
experimental research conducted in Malaysia which showed
that E. guineensis leaf extract had potent wound healing
capacity as evident from the better wound closure (p < 0.05),
improved tissue regeneration at the wound site, and supporting
histopathological parameters pertaining to wound healing
(Sasidharan et al., 2012). The wounds were treated topically
with 10% formulated crude extract (5 g of the extract in 50 g of
yellow soft paraffin), while the control rats were treated only
with yellow soft paraffin for 16 days. The decrease in wound
diameters during the healing process was measured with an
analytical perimeter. The wounded animals were kept for 25
days for further observations (Sasidharan et al., 2012).
Although the leaf of the oil palm is a waste product, the alcohol
extract of the leaf contains large amounts of phenolic
compounds (Sasidharan et al., 2009; Soundararajan and
Sreenivasan, 2012) that reportedly promote vascular relaxation
and anti-oxidant activity in vitro. A pooled methanolic extract
was dried under vacuum using a rotary evaporator and the
resultant waxy residue collected, freeze dried, flushed with
nitrogen and stored at –20°C. For vascular function studies, a
stock solution (100 mg/ml) was prepared using a 1:1 v/v
mixture of methanol: saline and serially diluted. Aliquots (25 –
50 µL) were added directly in a cumulative fashion to the bath
(aortic rings) or injected intraluminally (mesenteric vascular
bed (Abeywardena et al., 2002). In a recent study of
streptozotocin (STZ)-induced hyperglycemic rats, E. guineensis
leaf extract reduced glycemia and lipid oxidation in a dose-
dependent manner, possibly by inhibiting dipeptidyl peptidase-
4 (DPP-4) secretion (Tan et al., 2011).
Cardiovascualar activities
The polyphenol-rich leaf extract of E.guineensis showed
vasodilative properties on noradrenaline-preconstricted rat
aorta and mesenteric arterial bed, mainly via endothelium-
dependent mechanisms (Abeywardena et al., 2002). It also
effectively inhibited low-density lipoprotein oxidation better
than other edible plant extracts (Salleh et al., 2002). Also, in a
12-week study conducted by Jaffri et al. (2011) on rats, the leaf
extract showed good anti-hypertensive and anti-oxidant effects
under NO deficiency, it was not hypotensive to normal rats and
produced no chronic cardiovascular toxicity in any of the rats
throughout the study.
Hepatoprotective effects
Sasidharan et al. (2009) demonstrated the hepatoprotective
effects of E. guineensis against paracetamol induced liver
damage by looking at the histopathology of mice liver. This
was subsequently followed up by a serum analysis in which the
same authors (Sasidharan et al., 2012), reported that the
methanol extract of the leaves of the plant also offer
hepatoprotection against paracetamol induced-liver damage in
mice by reducing serum markers of liver injury such aspartate
aminotransferase, alanine aminotransferase, and billirubin.
Anti-diabetic effects
Kalman et al. (2013) reported that the ethanol-derived leaf
extract of E. Guineensis provided a clinically significant,
positive effect on fasting plasma glucose levels in individuals
with pre-diabetes who were treated with the leaf extract in a
dose dependent manner in human subjects. A 500 mg low dose
of E. guineensis was shown to have had a more consistent
effect on reducing glycemia than the higher 1000 mg dose over
an eight week period.
Anti-inflammatory activity
Oil palm ethanolic leaf extract (OPLE) at 150 mg/kg body
weight showed significant pro-inflammatory activity with
enhanced 46% late phase inflammation recovery effects. While
at high dose, inflammation was significantly suppressed prior
to the sixth hour compared to other groups, and did not require
much inflammation suppression between the 18th and 48th
hour. OPLE 150 mg/kg decreased lymphocyte counts, but was
not as severely as dexamethasone treatment. This result
suggests that OPLE extract possess strong in-vivo
inflammatory-regulatory effects (Anyanji et al., 2013).
The main problem for the use of oil palm leaf extract as
food in its natural form is its high content of insoluble fibre.
The OPLE effectively reduced blood glucose and lipid
oxidation in Type II diabetic humans and diabetes-induced
rodents. The optimum dose in animal studies is equivalent to
consuming 5 cups of 1% palm leaf extract for diabetic humans,
to prevent liver and kidney damage (Mohammed, 2014).
Sap of oil palm
Multiple actions
The oil palm sap or wine can be descried as the exudates that
flow when the palm is tapped (Obahiagbon, 2012). The sap of
this plant is also used as a laxative and the partially fermented
palm wine is administered to nursing mothers to improve
lactation (Sasidharan et al., 2012). The sap has also been
recorded to be involved in malaria, jaundice and measles
treatment. Just like the sap of other palms like Raphia,
researches conducted by authors like Obahiagbon and
Oviasogie (2007), and Obahiagbon et al. (2007) have shown
that the sap contains numerous phytonutrients which plays
significant roles in human health. Soap prepared with ash from
fruit-husk is used for the preparation of a soap used for skin
infections (Sasidharan et al., 2012).
Roots of oil palm
Multiple actions
A root decoction is used in Nigeria for headaches. The
pulverized roots are added to drinks for gonorrhea,
menorrhagia and as a cure for bronchitis (Sasidharan et al.,
2012; Irvin, 1985). Chong et al. (2009) demonstrated the in
vitro anti-microbial activity and fungitoxicity of syringic acid,
caffeic acid and 4-hydroxybenzoic acid which are found in oil
palm root. They also showed that of the three substances,
syringic acid was the most fungitoxic against G. boninense.
CONCLUSION
Oil palm (E. guineensis) parts and products have been used in
various parts of the world for different purposes. The traditional
uses of the different parts of the plant have been well
documented in this review. Virtually all the different parts of
the plant have one or more therapeutic effects. The plant has

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been used extensively in local treatment of various ailments
while the scientific uses of the plants have also been
documented. The therapeutic effects of this plant have been
attributed to the abundant anti-oxidants present in various parts
of the plant. However investigations on the actual mechanisms
by which the anti-oxidants perform their functions are still
ongoing. Also, this review shows that products obtained from
oil palm are safe for consumption at moderate doses in humans
and rodents.
ACKNOWLEDGEMENTS
The authors are grateful to their respective institutions for the
conductive environment provided for this review.
CONFLICT OF INTEREST
The authors declare that there are no conflicts of interest.
REFERENCES
Abdullah Z, Hussain K, Zhari I, Rasadah MA, Mazura P,
Jamaludin F, Sahdan R. Evaluation of extracts of leaf of three
Ficus deltoidea varieties for antioxidant activities and
secondary metabolites. Phcog Res. 2009;1:216-223.
Abeywardena M, Runny I, Nizar M, Mohamed S, Head R.
Polyphenol-enriched extract of oil palm fronds (Elaeis
guineensis) promotes vascular relaxation via endothelium-
dependent mechanisms. Asia Pac J Clin Nutr. 2002;11:S467-
S472.
Abulude FO, Ogunkoya MO, Ogunleye RF, Akinola AO,
Adeyemi AO. Effect of palm oil in protecting stored grains
from Sitophilus zeamais and Callosobruchus maculatus. J
Entomol. 2007;4:393-396.
Anyanji VU, Mohamed S, Zokti JA, Ado MA. Anti-
inflammatory properties of oil palm leaf (Elaeis guineensis
Jacq.) extract in aged rats. Int J Pharm Pharm Sci. 2013;5:134-
136.
Bester DJ, van Rooyen J, Du Toit EF, Esterhuyse AJ. Red palm
oil protects against the consequences of oxidative stress when
supplemented with dislipidaemic diets. Med Tech SA.
2006;21:3-6.
Boateng J, Verghese M, Chawan CB, Shackelford L, Walker LT,
Khatiwada J, Williams DS. Red palm oil suppresses the
formation of azoxymethane (AOM) induced aberrant crypt foci
(ACF) in fisher 344 male rats. Food Chem Toxicol.
2006;44:1667-1673.
Bonanome A, Grundy SM. Effect of dietary stearic acid and
plasma cholesterol and lipoprotein levels. New Eng J Med.
1988;318:1244-1248.
Bauer AW, Kirby WM, Sherris JC, Turck M. Antibiotic
susceptibility testing by a standardized single disk method. Am
J Clin Pathol. 1966;45:493-496.
Budin SB, Rajab NF, Osman K, Top AGM, Mohammed WNW,
Bakar MA, Mohamed J. Effects of palm vitamin E against
oxidative damage in Streptozotocin-induced diabetic rats.
Malaysian J Biochem Mol Biol. 2006;13:11-17.
Chong KP, Rossall S, Atong M. In vitro antimicrobial activity
and fungitoxicity of syringic acid, caffeic acid and 4-
hydroxybenzoic acid against Ganoderma boninense. J Agric
Sci. 2009;1:15-20.
Chong KH, Zuraini Z, Sasidharan S, Devi PVK, Latha LY,
Ramanathan S. Antimicrobial of Elaeis guineensis leaf.
Pharmacologyonline. 2008;3:379-386.
Chong YH, Ng TK. Effects of palm oil on cardiovascular risk.
Med J Malaysia. 1991;46:41-50.
Choudhury N, Tan L, Truswell AS. Comparison of palm olein
and olive oil: Effects on plasma lipids and Vitamins E in young
adults. Am J Clin Nutr. 1995; 61:1043-1051.
Corley RHV. Oil Palm Research. In the genus Elaeis, Corley
RHV, Hardon JJ, Wood BJ ed. (Amsterdam, Netherlands:
Elsevier Scientific Publisher), p. 532, 1976.
Cottrell RC. Introduction: nutritional aspects of palm oil. Amer
J Clin Nutr. 1991;53:989S-1009S.
Das S, Lekli I, Das M, Szabo G, Varadi J. Cardioprotection
with palm oil tocotrienols: Comparison of different isomers.
Am J Physiol Heart Circ Physiol. 2008;294:70-78.
Duke AJ. Handbook of Energy Crops. pp. 1-5, 1983. Available
at: https://www.hort.purdue.edu/newcrop/duke_energy/Elaeis
_guineensis.html (accessed on 01st May 2014).
Ebong PE, Owu DU, Isong EU. Influence of palm oil (Elaesis
guineensis) on health. Plant Food Hum Nutr. 1999;53:209-222.
Edem DO. Palm oil: Biochemical, physiological, nutritional,
hematological and toxicological aspects: a review. Plant Foods
Hum Nutr. 2002;57:319-341.
Edem DO. Vitamin A: A review. Asian J Clin Nutr. 2009;1:65-
82.
Edem DO, Akpanabiatu MI. Effects of palm oil-containing
diets on enzyme activities of rats. Pak J Nut. 2006;5:301-305.
Ekpa OD, Ebana RUB. Comparative Studies of Mmanyanga,
Palm and Coconut Oils; Anti-microbial Effects of the Oils and
their Metallic Soaps on Some Bacteria and Fungi. Global J
Pure and Appl Sci. 1996;2:155-163.
Ekwenye UN, Ijeomah CA. Antimicrobial effects of palm
kernel oil and palm oil. KMITL Sci J. 2005;5;502-505.
Elson CE. Tropical Oils: Nutritional and Scientific Issues. Crit
Rev Food Sci Nutr. 1992;31:79-102.
Engelbrecht AM, Esterhuyse AJ, Du Toit EF, Lochner A, Van
Rooyen J. P38-MAPK and PKB/Akt, possible role players in
red palm oil-induced protection of the isolated perfused rat
heart? J Nutr Biochem. 2006;17:265-271.
Esterhuyse AJ, Du Toit EF, Van Rooyen J. Dietary red palm oil
supplementation protects against the consequences of global
ischemia in the isolated perfused rat heart. Asia Pac J Clin Nutr.
2005;14:340-347.

Medicinal uses of oil palm
6
TANG / www.e-tang.org 2014 / Volume 4 / Issue 3 / e16
Goh SH, Khor HT, Gee PT. Phospholipids of palm oil (Elaeis
guineensis). J Am Oil Chem Soc. 1982;59:296-299.
Goh SH, Choo YM, Ong SH. Minor constituents of palm oil. J
Am Oil Chem Soc. 1985;62:237-240.
Gulecha V, Sivakuma T. Anticancer activity of Tephrosia
purpurea and Ficus religiosa using MCF 7 cell lines. Asian Pac
J Trop Med. 2011;4:526-529.
Guthrie N, Gapor A, Chambers AF, Carroll KK. Palm oil
tocotrienols and plant flavonoids act synergistically with each
other and with tamoxifen in inhibiting proliferation and growth
of estrogen receptor-negative MDA-MB-435 and -positive
MCF-7 human breast cancer cells in culture. Asia Pac J Clin
Nutr. 1997;6:41-45.
Hartley CWS. The Oil Palm. 1st ed. (London, England:
Longmans), p. 618, 1977.
Honstra G. Beneficial Effects of Palm oil on Arterial
Thrombosis (Rat) and Atherosclerosis (Rabbit). (Kuala Lumpur,
Malaysia: PORIM), pp. 35-45, 1986.
Irvin TT. Wound healing. Arch Emerg Med. 1985;2:3-10.
Jaffri JM, Mohamed S, Rohimi N, Ahmad IN, Noordin MM,
Manap YA. Antihypertensive and cardiovascular effects of
catechin-rich oil palm (Elaeis guineensis) leaf extract in nitric
oxide-deficient rats. J Med Food. 2011;14:775-783.
Kalman DS, Schwartz HI, Feldman S, Krieger DR. Efficacy
and safety of Elaeis guineensis and Ficus deltoidea leaf extracts
in adults with pre-diabetes. Nutr J. 2013;12:36.
Kooyenga DK, Gerler M, Watkins TR, Gapor A, Diakoumakis
E, Bierenbaum ML. Palm oil antioxidant effects in patients
with hyper-lipidaemia and carotid stenosis-2 year experience.
Asia Pac J Clin Nutr. 1997;6:72-75.
Krichevsky D. Effects of triglyceride structure on lipid
metabolism. J Nutr Rev. 1988;46:177-181.
Kritchevsky D, Tepper SA, Chen SC, Meijer GW. Influence of
triglyceride structure on experimental atherosclerosis in rabbits.
FASEB J. 1996;10:A187.
Kritchevsky D. Impact of red palm oil on human nutrition and
health. Food Nutr Bull. 2000;21:182-188.
Kumar RS, Rajkapoor B, Perumal P. In vitro and in vivo
anticancer activity of Indigofera cassioides Rottl. Ex. DC.
Asian Pac J Trop Med. 2011;4:379-385.
Law-Ogbomo KE, Egharevba RKA. The use of vegetable oils
in the control of Callosobruchus maculatus (F) (Coleoptera:
Bruchidae) in three cowpea varieties. Asian J Plant Sci.
2006;5:547-552.
Lietz G, Henry CJK, Mulokozi G, Mugyabuso J, Ballart A. Use
of red palm oil for the promotion of maternal vitamin A status.
Food Nutr Bull. 2000;21:215-218.
Manorama R, Rukmini C. Nutritional evaluation of crude palm
oil in rats. Am J Clin Nutr. 1991;53:1031-1033.
Marzuki A, Arshad F, Razak TA, Jaarin K. Influence of dietary
fat on plasma lipid profiles of Malaysian adolescents. Am J
Clin Nutr. 1991;53:1010-1014.
Mattson FH, Grundy SM. Comparison of effects of dietary
saturated, monounsaturated and polyunsaturated fatty acids on
plasma lipids and lipoproteins in man. J Lipid Res.
1985;26:194-202.
Mclntosch GH, Whyte J, McAthur R., Nestle, P. J. Barley and
wheat foods; Influence on plasma cholesterol cocntrations in
hypercholesterolemic men. Am J Clin Nutr. 1991;53:1205-1209.
McIntyre BS, Briski KP, Gapor A, Sylvester PW.
Antiproliferative and apoptotic effects of tecopherols and
tocotrienols on preneoplastic and neoplastic mouse mammary
epithelial cells. Proc Soc Exp Biol Med. 2000;224:292-301.
Mohamed S. Oil Palm Leaf: A New Functional Food Ingredient
for Health and Disease Prevention. J Food Process Technol.
2014;5:300.
Naher L, Yusuf UK, Ismail A, Tan SG, Mondal MMA.
Ecological status of Ganoderma and basal stem rot disease of
oil palms (Elaeis guineensis Jacq.) AJCS. 2013;7:1723-1727.
Nazaimoon WMW, Khalid BA. Tocotrienols-rich diet decreases
advanced glycosylation end products in non-diabetic rats and
improves glycemic control in Streptozotocin-induced diabetic
rats. Malays J Pathol. 2002;24:77-82.
Nesaretnam K, Tocotrienols inhibit the growth of human breast
cancer cells irrespective of estrogen receptor status. Lipids.
1998;33:461-469.
Nesaretnam K, Khor HT, Ganeson J, Chong K, Gapor A. The
effect of vitamin E tocotrienols from palm oil on chemically-
induced mammary carcinogenesis in female rats. Nutr Res.
1992;12:879-892.
Nesaretnam K, Ambra R, Selvaduray KR, Radhakrishnan A,
Reimann K, Razak G, Virgili F. Tocotrienol-rich fraction from
palm oil affects gene expression in tumors resulting from MCF-
7 cell inoculation in athymic mice. Lipids. 2004;39:459-467.
Ng TKW, Hayes KC, De Witt GF, Jegathesan M,
Satgunasingham N, Ong ASH, Tan DTS. Dietary palmitic and
oleic acids exert similar effects on serum cholesterol and
lipoprotein profiles in normocholesterolemic men and women.
J Am Coll Nutr. 1992;11:383-390.
Ng TKW, Hassan K, Lim JB, Lye MS, Ishak R.
Nonhypercholestrolemic effects of a palm oil diet in
Malasysian volunteers. Am J Clin Nutr. 1991;53:1015S-1020S.
Obahiagbon FI. A Review: Aspects of the African Oil Palm
(Elaeis guineesis jacq.) and the Implications of its Bioactives in
Human Health. Amer J Biochem Mol Biol. 2012;2:106-119.
Obahiagbon FI, Oviasogie PO, Ukhun ME, Oviawe PN.
Comparative studies of the thiamine and riboflavin contents in
the sap of Raphia hookeri palm by the application of
fluorimetric method and arrhenius equation. Tren Appl Sci Res.
2007;2:260-263.

Medicinal uses of oil palm
7
TANG / www.e-tang.org 2014 / Volume 4 / Issue 3 / e16
Obahiagbon FI, Oviasogie PO. Changes in the physicochemical
characteristics of processed and stored Raphia hookeri palm
sap (shelf-life studies). Am J Food Technol. 2007;2:323-326.
Oguntibeju OO, Esterhuyse AJ, Truter EJ. Possible role of red
palm oil supplementation in reducing oxidative stress in
HIV/AIDS and TB patients: A review. J Med Pl Res.
2010;4:188-196.
Oluba OM, Onyeneke CE, Ojieh GC, Eidangbe GO, Orole RT.
Effects of Palm Oil Supplementation on Lipid Peroxidation and
Glutathione Peroxidase Activity in Cholesterol – Fed Rats. The
Internet J Cardio Res. 2009;6:1.
Packer L. Interactions among antioxidants in health and disease:
Vitamin E and its redox cycle. Exp Biol Med. 1992;200:271-
276.
Packer L, Serbinova E, Choo M. Distribution and antioxidant
activity of a palm oil carotene in rats. Biochem Inter.
1992;28:881-886.
Qureshi AA, Qureshi N, Wright JJ, Shen Z, Kramer G.
Lowering of serum cholesterol in hypercholesterolemic humans
by tocotrienols (palmvitee). Am J Clin Nutr. 1991;53;1021-
1026.
Qureshi A, Burger WC, Prentice N, Bird HR, Sunde ML.
Regulation of Lipid metabolism in chicken liver by dietary
cereals. J Nutr. 1980;110:388-393.
Qureshi AA, Pearce BC, Parker RA, Deason ME. Response of
hypercholesterolemic subjects to administration of tocotrienols.
Lipids. 1995;30: 1171-1177.
Rajoo A, Ramanathan S, Sasidharan S, Mansor SM.
Standardization of Elaeis guineensis with respect to
authenticity, assay and chemical constituent analysis. Afr J
Biotechnol. 2010;9:7544-7549.
Rasool AHG, Yuen KH, Yusoff K, Wong AR, Rahman AR.
Dose dependent elevation of plasma tocotrienol levels and its
effect on arterial compliance, plasma total antioxidant status,
and lipid profile in healthy humans supplemented with
tocotrienol rich vitamin E. J Nutr Sci Vitaminol. 2006;52:473-
478.
Rao BSN. Potential use of red palm oil in combating vitamin A
deficiency in India. Food Nutr Bull. 2000;21:202-211.
Rosalina Tan RT, Mohamed S, Samaneh GF, Noordin MM,
Goh YM, Manap MYA. Polyphenol rich oil palm leaves extract
reduce hyperglycaemia and lipid oxidation in STZ-rats. Int
Food Res J. 2011;18:179-188.
Rukmini C. Red palm oil to combat vitamin A deficiency in
developing countries. Food Nutr Bull 1994;15:126-129.
Runnie I, Mustapha NM, Radzali M, Azizah H, Hapizah N,
Abeywardena MY, Mohamed S. Antioxidant and hypocholes-
terolemic effects of Elaeis guineensis frond extract on hyper-
cholesterolemic rabbits. Asean Food J. 2003;12:137-147.
Salleh MN, Runnie I, Roach PD, Mohamed S, Abeywardena
MY. Inhibition of low-density lipoprotein oxidation and up-
regulation of low-density lipoprotein receptor in HepG2 cells
by tropical plant extracts. J Agric Food Chem. 2002;50:3693-
3697.
Sasidharan S, Vijayarathna S. Cytotoxicity of methanol extracts
of Elaeis guineensis on MCF-7 and Vero cell lines. Asian Pac J
Trop Biomed. 2012;2:826-829.
Sasidharan S, Nilawatyi R, Xavier R, Yoga Latha L, Amala R.
Wound healing potential of Elaeis guineensis Jacq leaves in an
infected albino rat model. Molecules. 2010;15:3186-3199.
Sasidharan S, Selvarasoo L, Latha LY. Wound Healing Activity
of Elaeis guineensis Leaf Extract Ointment. Int J Mol Sci.
2012;13:336-347.
Sasidharan S, Vijayarathna S, Jothy SL, Ping KY, Latha LY.
Hepatoprotective potential of Elaeis guineensis leaf against
paracetamol induced damage in mice: A serum analysis.
IPCBEE. 2012;39:231-234.
Sasidharan S, Sharmini R, Vijayarathna S, Yoga Latha, L,
Vijenthi R, Amala R, Amutha S. Antioxidant and
hepatoprotective activity of methanolic extracts of Elaeis
Guineensis Jacq leaf. Pharmacologyonline. 2009;3:84-90.
Serbinova E, Kagan V, Han D, Packer L. Free Radical
Recycling and Intramembrane Mobility in the Antioxidant
properties of Alpha-tocopherol and Alpha-tocotrienol. Free
Radic Biol Med. 1991;10:263-275.
Solomons NW. Plant sources of vitamin A and human nutrition:
red palm oil does the job. Nutr Rev. 1998;56:309-311.
Song BL, DeBose-Boyd RA. Insig-dependent ubiquitination
and degradation of 3-hydroxy-3-methylglutaryl coenzyme a
reductase stimulated by δ- and γ-tocotrienols. J Biol Chem.
2006;281:25054-25061.
Soundararajan V, Sreenivasan S. Antioxidant activity of Elaeis
guineensis leaf extract: An alternative nutraceutical approach in
impeding aging. APCBEE Procedia. 2012;2:153-159.
Sundram K, Khor HT, Ong SHA, Pathmanthan R. Effect of
dietary palm oils on mammary carcinogenesis in female rats
induced by 7, 12-dimehtlbenz (a) anthra-cene. Cancer Res.
1989;49:1447-1451.
Sundram K, Hornstra G, Houwelingen AC. Replacement of
dietary fat with palm oil: Effect on human serum lipid,
lipropotein and apoproteins. Br J Nutr. 1992;68:677-692.
Sundram K, Khor HT, Ong ASH. Effect of dietary palm oil and
its fractions on rat plasma and high density lipoprotein lipids.
Lipids. 1990;25:187-193.
Syahmi ARM, Vijayarathna S, Sasidharan S, Latha LY, Kwan
YP, Lau YL, Shin LN, Chen Y. Acute oral toxicity and brine
shrimp lethality of Elaeis guineensis jacq., (oil palm leaf)
methanol extract. Molecules. 2010;15:8111-8121.
Tan RT, Mohamed S, Samaneh GF, Noordin MM, Goh YM,
Manap MYA. Polyphenol rich oil palm leaves extract reduce
hyperglycaemia and lipid oxidation in STZ-rats. Int Food Res J.
2011;18:179-188.
Truswell AS, Choudhury N, Roberts DCK. Double blind
comparison of plasma lipids in healthy subjects eating potato

Medicinal uses of oil palm
8
TANG / www.e-tang.org 2014 / Volume 4 / Issue 3 / e16
crisps fried in palmolein or canola oil. Nutr Res.1992;12:S34-
S52.
Van Rooyen J, Esterhuyse AJ, Engel brecht A, Toit EF. Health
benefits of natural carotenoid rich oil: a proposed mechanism
of protection against ischemia reperfusion injury. Asia Pac J
Clin Nutr. 2008;17:316-319.
Wu SJ, Liu PL, Ng LT. Tocotrienol-rich fraction of palm oil
exhibits anti-inflammatory property by suppressing the
expression of inflammatory mediators in human monocytic
cells. Mol Nutr Food Res. 2008;52:921-929.
Yamabe N, Yokozawa T, Oya T, Kim M. Therapeutic potential
of (−)-epigallocatechin 3-O-gallate on renal damage in diabetic
nephropathy model rats. J Pharmacol Exp Ther. 2006;319:228-
236.
Zhang J, Wang CR, Dai J, Chen XS, Ge KY. Palm oil diet may
benefit mildly hyper cholestrerolaemic Chinese adults. Asia
Pac J Clin Nutr. 1997;6:22-25.
Zuzana M, Suhana M, Zalinah A, Gapor MT, Ngah WZW.
Comparative effects of α-tocopherol and γ tocotrienol on lipid
peroxidation status in Hep G2 cell live transfected with CYZEI
gene. Eur J Sci Res.2005;7:41-56.