American Journal of Food Science and Nutrition Research
2016; 3(5): 96-101
http://www.openscienceonline.com/journal/fsnr
ISSN: 2381-621X (Print); ISSN: 2381-6228 (Online)
Proximate and Phytochemical Compositions of
Ricinus communis in Ibadan, South-Western
Nigeria
Akinyemi O.*, E. W. Iyebor, C. O. Osadebe, N. S. Oniroko
Forestry Research Institute of Nigeria, Ibadan, Nigeria
Email address
[email protected] (Akinyemi O.), [email protected] (N. S. Oniroko), [email protected] (C. O. Osadebe),
[email protected] (E. W. Iyebor)
*
Corresponding author
To cite this article
Akinyemi O., E. W. Iyebor, C. O. Osadebe, N. S. Oniroko. Proximate and Phytochemical Compositions of Ricinus communis in Ibadan,
South-Western Nigeria. American Journal of Food Science and Nutrition Research. Vol. 3, No. 5, 2016, pp. 96-101.
Received: June 10, 2016; Accepted: June 21, 2016; Published: August 6, 2016
Abstract
The analyses of seeds of Ricinus communis collected from Ibadan, South Western Nigeria were carried out to determine its
proximate and phytochemical compositions. The proximate analysis showed that the percentage of crude fat was greater than
that of crude protein followed by the percentage of crude fibre, moisture and ash respectively. The contents of moisture, crude
protein, crude fat, crude fibre, ash and total carbohydrate were 6.397, 26.64, 59.43, 12.72, 3.177 and 4.360% respectively. The
phytochemical screening revealed presence of Alkaloids (+++), Cardiac Glycosides (++), Saponins (+++), Tannins (+),
Flavonoids (+), Phenol (++), Phobatannin (+) and Anthraquinone (+). The quantitative analysis showed varying concentrations
of alkaloids (0.8815 cmol/kg), cardiac glycosides (0.0745 cmol/kg), saponins (1.2315 cmol/kg), flavonoids (0.0022 cmol/kg)
and phenol (0.0905 cmol/kg). Other constituents investigated in castor bean seeds such as steroids, terpene, cardenolides and
chalcones were completely absent. The percentages of crude protein and fat obtained as well as phytochemical constituents
present suggest that Ricinus communis seeds could be a good source of protein for humans consumption and livestock feeding,
oil for industrial uses and medicine for treating various ailments.
Keywords
Castor Bean Seeds, Proximate, Phytochemicals, Ricin Detoxification
1. Introduction
The general use of plants in medicines, foods, cosmetics,
oxygen production, aesthetics, timber, etc cannot be overemphasized. Traditional medicine which involves the use of
plant materials in treating various ailments has proven to be
highly efficacious if the appropriate dose is administered.
Besides, some plants are eaten as foods either fresh or
processed and at the same time, serve as medicine. Ricinus
communis suggests being one of such plants.
Ricinus communis is a species of flowering plant in the
spurge family, classified under Euphorbiaceae. It is
commonly called Castor plant, Castor oil plant and Castor
bean plant. It is called Wonderboom or Wonder tree in South
Africa, Eranda plant in India and Palma Christi in Jordan. In
Nigeria, various tribes call it different names such as Ogilisi
in Igbo, Laraa in Yoruba and Zurman in Hausa. Castor bean
is native to the Ethiopian region of tropical Africa and has
become naturalized in tropical and temperate regions
throughout the world Akande et al., [1]. It grows best in full
sun and can reach heights of up to 40 feet. In colder climates
where temperatures drop below freezing point, castor bean
functions like an annual plant and only reaches heights of 15
feet. Leaves are simple and alternate and can grow very large
from 15 – 30 inches wide. The leaves are green to reddish
and are lopsidedly peltate, with the petiole attaching to the
interior of the blade above the center point. Each leaf has 5 –
11 major veins radiating outward into narrow lobes with
jagged margins. The plant consists of several branches, each
97
Akinyemi O. et al.: Proximate and Phytochemical Compositions of Ricinus communis in Ibadan, South-Western Nigeria
terminated by a spike. The mature spike is 15 – 30 cm long
and each bears 15 – 80 capsules [2]-[3]. A capsule contains
three or four seeds each, which at maturity, splits to release
the seeds. The Castor oil makes up 35% to 55% of the weight
of the seeds and the oil contains 85% to 95% ricinoleic acid
[2]-[3]-[4].
The oil extracted from castor bean seed has been used in
medicines, cosmetics, biodiesel, plastics and lubricant
production Salihu et al., [5]. The leaves of Ricinus communis
have been reported to contain flavonoids, rutin, quercetin and
polyphenols and are being used along with turmeric paste to
treat inflammation manifestations in North India [6]-[7]-[8].
The roots have also been reported to possess antiinflammatory, anti-oxidative and anti-diabetic properties [9][10]. The cake or de-oiled residue contains 48% crude
protein and the whole seed containing 2.9 – 3.28 kcal/kg
[11]-[12]-[1]. Every part of castor bean is proven to be
useful.
In Eastern Nigeria, the leaves and stems are used as raw
materials for the production of local soap (black soap
popularly called Ncha-ude in Igbo) while the processed seeds
locally called Ogilisi is used as soup condiment. Local
seasoning produced from castor bean (Ogilisi) can be used
singly to cook special variety of soups or combined with
bouillons. For instance, it is commonly used to cook bitter
leaf and egusi soup among the Igbos. In fact, most homes in
this part of Nigeria prefer Ogilisi processed from castor bean
seed to synthetic food seasonings such as Maggi, Knorr,
Royco, Doyin, Jumbo, Suppy etc because of its suspected
nutritional and medicinal values.
In spite of the wide applications or uses of castor bean
plant, it has however been reported in some literatures as a
poisonous and non-edible oilseed plant. According to Akande
et al., [1]. the leaves, seeds and stems contain glycoprotein
ricin which is poisonous to humans and animals. Castor bean
with its wide uses has over the years been limited and underutilized by man due to its ricin component. Hence, the
present study sheds light on the local processing method that
detoxifies glycoprotein ricin contained in castor bean seed as
well as its nutritional and phytochemical compositions.
Plate 2. Castor Bean Seed.
2. Materials and Methods
Castor bean seeds were collected from Ibadan, South West
Nigeria and identified at Forestry Research Institute of
Nigeria, Ibadan, Oyo State, Nigeria.
2.1. Local Method of Processing Castor Bean
Seed (Ogilisi)
Castor bean seeds were harvested from castor plant and air
sun-dried for 7days. The outer coating of the seeds referred to
as husks were removed manually and the residue wet pulp
were collected and put into a pot and boiled at 100 0C for 1
hour. The oil contained in the pulp that settled on top of the
mixture was decanted and the boiled pulp allowed cooling at
room temperature. Boiled pulp was wrapped in leaves of
Thaumatococcus danielli for 4 days to allow fermentation to
take place and thereafter, the pulp was blended with mortar
and wrapped in the same leaves (Thaumatococcus danielli)
for another 2 days for further fermentation to take place. The
leaves were removed at the appearance of black spot on the
blended pulp indicating its readiness for use as soup
condiment. During this process, ricinoleic acid is detoxified
making it non poisonous and edible.
2.2. Proximate Analysis
Proximate composition of castor bean seeds was carried
out according to the procedure of AOAC [13]. The crude
protein was determined by the Kjeldahl method as described
by AOAC [13]. Crude protein content was estimated at 6.25
multiple of the nitrogen value. Crude fiber determination was
carried out using the trichloroacetic acid (TCA) method.
Carbohydrate was calculated by difference while ash and
crude fat contents were determined according to AOAC [13].
2.3. Qualitative and Quantitative Analyses
Plate 1. Processed Castor Bean (Ogilisi) used as food condiment
(seasoning) in Eastern Nigeria.
The de-husked seeds (wet pulp) were soaked in deionized
water for 1 hour and thereafter, the aqueous extract is used
for phytochemical screening.
American Journal of Food Science and Nutrition Research 2016; 3(5): 96-101
2.4. Phytochemical Screening (Qualitative
Analysis)
Phytochemical screening to test for the presence of
alkaloids, saponins, flavonoids, polyphenols, reducing
sugars, phlobatannins, anthraquinones, glycosides, tannins
and hydroxymethyl anthraquinone in the pulps of castor bean
seeds were carried out in extracts using the standard
procedures as described by Sofowora [14], Trease and Evans
[15], Harbone [16].
2.5. Quantitative Analysis
Alkaloid determination by Harbone [16]: Five grams of
the sample was weighed into a 250 ml beaker and 200 ml of
10% acetic acid in ethanol was added and covered and
allowed to stand for 4 hours. This was filtered and the extract
was concentrated on a water bath to one-quarter of the
original volume. Concentrated ammonium hydroxide was
added drop wise to the extract until the precipitation was
complete. The whole solution was allowed to settle and the
precipitate was collected and washed with diluted ammonium
hydroxide and then filtered. The residue alkaloid was dried
and weighed.
Saponin Determination using Spectrophotometric Method
by Brunner [17]: One gram of finely ground sample was
weighed into a 250ml beaker and 100ml of isobutyl alcohol
was added. The mixture was shaken on a shaker for 5 hours
to ensure uniform mixing. Thereafter the mixture was filtered
through a Whatman No1 filter paper into a 100 ml beaker and
20 ml of 40% saturated solution of magnesium carbonate was
added. The mixture obtained with saturated MgCO3 was
again filtered through a Whatman No1 filter paper to obtain a
clear colourless solution. 1ml of the colourless solution was
pipetted into 50ml volumetric flask and 2ml of 5% FeCL3
solution was added and made up to mark with distilled water.
It was allowed to stand for 30 min for red colour to develop.
0-10 ppm standard Saponin solutions were prepared from
saponin stock solution. The standard solutions were treated
similarly with 2ml of 5% FeCL3 solution as done for 1ml
sample above. The absorbance of the sample as well as
standard saponin solutions were read after colour
development in a Jenway V6300 Spectrophotometer at a
wavelength of 380nm. of 380nm.
% Saponin =
x 10,000
98
3. Results and Discussion
3.1. Results
The proximate analysis revealed percentages of various
nutrients in the seed of Ricinus communis. The trend
followed this order; % crude fat was greater than % crude
protein followed by % crude fibre, % moisture and % ash
respectively (Table 1). The contents of moisture, crude
protein, crude fat, crude fat, crude fibre, ash and total
carbohydrate were 6.397, 26.64, 59.43, 12.72, 3.177 and
4.360% respectively. The phytochemical screening showed
presence of Alkaloids (+++), Cardiac Glycosides (++),
Saponins (+++), Tannins (+), Flavonoids (+), Phenol (++),
Phobatannin (+) and Anthraquinone (+). The quantitative
analysis revealed varying concentrations of alkaloids
(0.8815 cmol/kg), cardiac glycosides (0.0745 cmol/kg),
saponins (1.2315 cmol/kg), flavonoids (0.0022 cmol/kg)
and phenol (0.0905 cmol/kg). Other constituents
investigated in castor bean seed such as steroids, terpene,
cardenolides and chalcones were completely absent (Table
2).
Table 1. Results of Proximate Analysis of Ricinus communis in Ibadan,
Nigeria.
S/N
Proximate (Nutrients)
Value
1
% Moisture Content
6.397
2
% Crude Protein
26.64
3
% Crude Fat
59.43
4
% Crude Fibre
12.72
5
% Ash
3.177
6
CHO
4.360
Table 2. Results of Qualitative and Quantitative (cmol/kg) Analyses of
Ricinus communis in Ibadan.
S/N
Chemical
constituents
Sample
extract(Qualitative)
Quantities
(cmol/kg)
1.
Alkaloids
+++
0.8815
2.
Cardiac Glycosides
++
0.0745
3.
Saponins
+++
1.2315
4.
Tannins
+
-
5.
Flavonoids
+
0.0022
6.
Phenol
++
0.0905
7.
Phobatannin
+
-
2.6. Phenol Determination by
Spectrophotometric Method
8.
Anthraquinone
+
-
9.
Steroids
-
-
The fat free sample was boiled with 50 ml of ether for the
extraction of the phenolic component for 15 min. 5 ml of the
extract was pipetted into a 50 ml flask, then 10 ml of distilled
water was added. 2 ml of ammonium hydroxide solution and
5 ml of concentrated amyl alcohol were also added. The
samples were made up to mark and left to react for 30 min
for colour development. This was measured at 505 nm.
10.
Terpene
-
-
11
Cardenolides
-
-
12
Chalcones
-
-
Legend
+ Present in trace amount
++ Present in moderate amount
+++ Present in appreciable amount
--- Absent
99
Akinyemi O. et al.: Proximate and Phytochemical Compositions of Ricinus communis in Ibadan, South-Western Nigeria
lower high blood cholesterol level. Low level crude fibre is
considered appropriate [22], because high level can cause
intestinal irritation, lower digestibility and decreased nutrient
usage [23].
The moisture (6.397%) and ash (3.177%) obtained were
low. Moisture content is among the most vital factors
considered in food processing, preservation and storage [24].
The low percentage of moisture obtained indicates that castor
bean seeds have low shelf-life, implying that its long storage
could lead to spoilage due to susceptibility to microbial
attack [22].
Figure 1. A Graph Showing Various Nutrients and their values in Ricinus
communis.
Figure 2. A Graph Showing Selected Phytochemicals with Degree of
Presence and their Quantities in Ricinus communis.
3.2. Proximate Composition
The crude protein (26.64%) obtained in this study
indicates that castor bean seed is a good source of protein.
Proteins are major source of energy. It contains essential
amino acids responsible for growth and repair of worn-out
tissues in humans. Although castor bean seed has been
reported in literatures as toxic because of the ricin it contains
[3]-[1], the local method of processing it for use as food
seasoning detoxifies the ricin and makes it a preferred choice
among varieties of food seasonings especially in Eastern
Nigeria. The percentage crude protein obtained in the present
study is slightly higher than (22.11%) reported by Akande et
al., [1]. This difference may be due to calibration standards
and procedures during analysis. Bouba et al., [18] found the
same observation in a similar study and attributed it to
difference in standard used for the analysis.
The percentage crude fat (59.43%) obtained was higher
than other nutrients investigated and according to Ayoola et
al., [19], high fat content in any seed makes it a good source
of nutrient that has the potential to improve the energy
density of man and animals. Fats aid transport of fat-soluble
vitamins insulates and protects internal tissues and
contributes to important cell processes [20]-[21]. Crude fibre
recorded in the present study (12.72%) indicates the level of
non-digestible carbohydrate and lignin in castor bean seed.
Fibre is characterized by low or no nutritional value however,
its effect on digestive system may help to fight diabetes and
3.3. Phytochemical Analysis
The degree of presence of Alkaloids and saponins recorded
in this study was high. Alkaloids are nitrogenous organic
molecule that has a pharmacological effect on humans and
animals. Although castor bean seed is locally processed and
used as food seasoning among Igbos in Eastern Nigeria, the
high degree of presence of alkaloids (+++) and saponins
(+++) in castor bean seed suggests that it can be used as
medicine. Saponins are group of chemicals with detergentlike properties that plants produce to help resist microbial
pathogens. Alkaloids and saponins prevent excessive
intestinal absorption of cholesterol and reduce the risk of
cardiovascular diseases such as hypertension [25]. Saponins
had the highest quantity (1.2315 cmol/kg) among the
constituents investigated. Saponins have antitumor and
antimutagenic activities and can lower the risk of human
cancers, by preventing cancer cells from growing [26].
Aqueous solution containing saponins froth greatly which
may be the reason they are used as detergents [27]. The high
presence and quantity of saponins in castor bean seed
recorded in the present research justified the use of the plant
as a raw material in local soap (Ncha-Ude) making in Eastern
Nigeria.
Phenol had a quantity of (0.0905 cmol/kg) and (++) degree
of presence in castor bean seed studied. Polyphenol is a
natural chemical in plants and plants with high polyphenol
content have been said to be antioxidants. Antioxidants are
compounds that have the ability to delay or inhibit the
oxidation of lipids and other molecules by inhibiting the
initiation of oxidizing chain reactions [28]. The antioxidant
activity of polyphenols is mainly due to their redox
properties, which can play an important role in adsorbing and
neutralizing free radicals, quenching oxygen, or decomposing
perioxides [28]. According to Slattery et al., [29], intakes of
phenols, vitamin C and carotenoid-rich food or vegetables is
associated with decreased incidence of some cancers and
cardiovascular diseases.
Flavonoids act as antioxidant by removing the highly
unstable molecules called free radicals which damage the
body cells [30]-[31]. The degree of presence (+) and quantity
(0.0022 cmol/kg) of flavonoid obtained in this study were
low. Flavonoids are a group of polyphenolic compounds with
known properties including free radical scavenging,
inhibition of hydrolytic and oxidative enzymes and antiinflammatory action [32]. Flavonoids have been reported as
American Journal of Food Science and Nutrition Research 2016; 3(5): 96-101
having antibacterial, anti-inflammatory, anti-allergic, antimutagenic and anti-viral actions [27].
Glycosides are important in medicine because of their
action on the heart referred to as cardiac glycosides. Cardiac
glycosides recorded in this study showed degree of presence
of (++) and a quantity of 0.0745 cmol/kg. Preparations
containing glycosides are used for the treatment of certain
skin cancers [33].
4. Summary and Conclusion
The proximate analysis of seeds of Ricinus communis
revealed percentages of various nutrients. The nutrients
obtained were in this order; crude fat (59.43%) > crude
protein (26.64%) > crude fibre (12.72%) > moisture
(6.397%) > total carbohydrate (4.360) > ash (3.177%). The
phytochemical screening showed presence of Alkaloids
(+++), Cardiac Glycosides (++), Saponins (+++), Tannins
(+), Flavonoids (+), Phenol (++), Phobatannin (+) and
Anthraquinone (+). The quantitative analysis revealed
varying concentrations of alkaloids (0.8815 cmol/kg), cardiac
glycosides (0.0745 cmol/kg), saponins (1.2315 cmol/kg),
flavonoids (0.0022 cmol/kg) and phenol (0.0905 cmol/kg).
Other constituents investigated in castor bean seed such as
steroids, terpene, cardenolides and chalcones were
completely absent. This paper has revealed that ricin
contained in castor bean seeds could be detoxified locally
thus making it edible. The proximate and phytochemical
compositions of Ricinus communis suggest that the seeds can
be a good source of protein for humans and livestock, oil for
industrial uses and medicine for treating various ailments.
However, further studies are recommended on the processed
seeds of Ricinus communis.
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