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

akindapo4real@yahoo.com (Akinyemi O.), onirokoniyi@yahoo.com (N. S. Oniroko), ogeosadebe@gmail.com (C. O. Osadebe),

wisdomiyebor@yahoo.com (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 over-

emphasized. 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 anti-

inflammatory, 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 under-

utilized 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 1. Processed Castor Bean (Ogilisi) used as food condiment

(seasoning) in Eastern Nigeria.

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

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 98

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

2.6. Phenol Determination by

Spectrophotometric Method

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.

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 + -

8. Anthraquinone + -

9. Steroids - -

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

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

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].

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 detergent-

like 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 anti-

inflammatory action [32]. Flavonoids have been reported as

American Journal of Food Science and Nutrition Research 2016; 3(5): 96-101 100

having antibacterial, anti-inflammatory, anti-allergic, anti-

mutagenic 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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