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Special Conference Edition
, November, 2017
Bayero Journal of Pure and Applied Sciences:
ISSN 2006 – 6996
DETERMINATION OF CAFFEINE CONTENT IN SOME VARIETIES OF KOLA
*
Department of Chemistry, Sa’adatu Rimi College of Education,
*Correspondence author
ABSTRACT
The possibility of moisture, fat and caffeine contents of variety of kola nut (Cola acuminate)
to
differ with freshness and growing soil was tested. Varieties of kola nut‘Sabo Dan Ikko’,
‘Daushe Dan Ikko’,‘Sabo Dan Accra’ and ‘Daushe Dan Accra’ were obtained from Mariri kola
nut market (‘Yangoro), Kano. The moisture content of the four varieties of k
acuminate, were determined by drying the grated samples at 105
result was obtained as,30.58 ± 0.32, 20.80 ± 0.22, 36.62 ± 0.23 and25.16 ± 0.31% for ‘Sabo
Dan Ikko’, ‘Daushe Dan Ikko’, ‘Sabo Dan Accra’ and
dried samples were defatted using the Soxhlet apparatus and petroleum ether of 60
boiling point and the following fat contents were obtained, 2.53 ± 0.25, 2.80 ± 0.03, 2.61 ±
0.35 and 2.72 ± 0.22% for ‘Sabo Dan Ikko’, ‘Daushe Dan I
Dan Accra’
respectively. The caffeine was extracted by the use of chloroform and the
contents were found to be, 600mg/20g (3.00%), 580mg/20g (2.90%), 540mg/20g (2.70%) and
500mg/20g (2.50%) for ‘Sabo Dan Ikko’,‘Daushe Da
Accra’ respectively. The results showed that generally the Lagos varieties contain more
caffeine than the Accra ones.
Keywords: Kolanut, ‘Daushe’, ‘Sabo’, Caffeine, Kano
INTRODUCTION
Kola nut is a caffeine containi
ng nut of ever
green tree of the genus kola with prima
species, Cola acuminate and cola nitida. Cola
acuminate
is an ever green tree of about 20
meters in height and has long ovoid leave
pointed at both the end with a leathery
texture. The trees ha
ve yellow flower with
purple spot, and star shaped fruit with about a
dozen round or square seeds which can be
found in white seed shell. The tree is grown
commercially around the world, particularly in
Nigeria, Sri lanka, Indonesia, Brazil and other
parts
of South America. The tree is propagated
through seed and, C. nitidaand
C. acuminate
can easily be interchange with
species
. Kola nut is extremely popular amongst
the inhabitant as a caffeine containing
stimulant. The nut aroma is sweet and ros
like. At first the taste is bitter but sweetens
upon chewing. The nuts are eaten whole or
powdered and mixed with liquid for a drink
t
hus, sometimes used as flavoring ingredients in
bever
ages (Kuoame and Scande, 2006).
The use of kola nut, like the coff
berry and tea leaf, appears to have ancient
origin. It is chewed in many West African
culture, individually or in social setting to
restore vitality and ease hunger pangs. Kolanut
is an important part of traditional spiritual
practice of culture and rel
igion in West Africa,
, November, 2017
Bayero Journal of Pure and Applied Sciences:
10(1): 247 - 251
DETERMINATION OF CAFFEINE CONTENT IN SOME VARIETIES OF KOLA
NUT (C. acuminate)
*
Yalwa, I.R. and Bello, A.M.
Department of Chemistry, Sa’adatu Rimi College of Education,
Kumbotso. P.M.B. 3218 Kano
Nigeria.
*Correspondence author
:ibrahimr.yalwa@ymail.com
;
+2348038343900
The possibility of moisture, fat and caffeine contents of variety of kola nut (Cola acuminate)
differ with freshness and growing soil was tested. Varieties of kola nut‘Sabo Dan Ikko’,
‘Daushe Dan Ikko’,‘Sabo Dan Accra’ and ‘Daushe Dan Accra’ were obtained from Mariri kola
nut market (‘Yangoro), Kano. The moisture content of the four varieties of k
acuminate, were determined by drying the grated samples at 105
0
Cfor 48 hours and the
result was obtained as,30.58 ± 0.32, 20.80 ± 0.22, 36.62 ± 0.23 and25.16 ± 0.31% for ‘Sabo
Dan Ikko’, ‘Daushe Dan Ikko’, ‘Sabo Dan Accra’ and
‘Daushe Dan Accra
’ respectively. The
dried samples were defatted using the Soxhlet apparatus and petroleum ether of 60
boiling point and the following fat contents were obtained, 2.53 ± 0.25, 2.80 ± 0.03, 2.61 ±
0.35 and 2.72 ± 0.22% for ‘Sabo Dan Ikko’, ‘Daushe Dan I
kko’, ‘Sabo Dan Accra’ and
respectively. The caffeine was extracted by the use of chloroform and the
contents were found to be, 600mg/20g (3.00%), 580mg/20g (2.90%), 540mg/20g (2.70%) and
500mg/20g (2.50%) for ‘Sabo Dan Ikko’,‘Daushe Da
n Ikko’, ‘Sabo Dan Accra’, ‘Daushe Dan
Accra’ respectively. The results showed that generally the Lagos varieties contain more
Keywords: Kolanut, ‘Daushe’, ‘Sabo’, Caffeine, Kano
ng nut of ever
green tree of the genus kola with prima
rily the
species, Cola acuminate and cola nitida. Cola
is an ever green tree of about 20
meters in height and has long ovoid leave
pointed at both the end with a leathery
ve yellow flower with
purple spot, and star shaped fruit with about a
dozen round or square seeds which can be
found in white seed shell. The tree is grown
commercially around the world, particularly in
Nigeria, Sri lanka, Indonesia, Brazil and other
of South America. The tree is propagated
C. acuminate
can easily be interchange with
other cola
. Kola nut is extremely popular amongst
the inhabitant as a caffeine containing
stimulant. The nut aroma is sweet and ros
e-
like. At first the taste is bitter but sweetens
upon chewing. The nuts are eaten whole or
powdered and mixed with liquid for a drink
hus, sometimes used as flavoring ingredients in
ages (Kuoame and Scande, 2006).
The use of kola nut, like the coff
ee
berry and tea leaf, appears to have ancient
origin. It is chewed in many West African
culture, individually or in social setting to
restore vitality and ease hunger pangs. Kolanut
is an important part of traditional spiritual
igion in West Africa,
particularly Nigeria (Somadhi, 2004). Kolanut is
used as a religious object and scared offering
during prayers, ancestors’ venerations and
significant life events such as naming
ceremonies, weddings and funerals. It is also
used in tr
aditional divination system called Obi
divination among the Igbo’s. For this purpose
kola nut divided in to four lobes is suitable. The
nuts are cast upon a special wooden board and
resulting patterns are read by a trained diviner.
This ancient practice is
currently enjoying
increased growth within the United State and
Caribbean
. Kola nut is preferred among African
Muslims who are forbidden to drink alcohol
(Blades, 2000
). Chewing kola nut can ease
hunger pangs and is often used to treat
whooping cough and
asthma (Steinegger and
Hansel, 1992). The caffeine present acts as a
bronchodilator, expanding the bronchial air
passages (Jayeola, 2001
). However, frequent
chewing of the kolanut can lead to stained
teeth (Jarvis, 2002).
Various medicinal and pharmacolog
values have been observed in species of cola.
Fresh kola nuts have stimulant action apart
from the caffeine content, as they appear in
European commerce. Their action is
indistinguishable from that of other caffeine
drugs (Jayeola, 2001). Caffeine in
works by stimulating the central nervous system
(CNS), heart and muscles (Ratsch, 2005).
http://dx.doi.org/10.4314/bajopas.v10i1.50S
247
DETERMINATION OF CAFFEINE CONTENT IN SOME VARIETIES OF KOLA
Kumbotso. P.M.B. 3218 Kano
-
The possibility of moisture, fat and caffeine contents of variety of kola nut (Cola acuminate)
differ with freshness and growing soil was tested. Varieties of kola nut‘Sabo Dan Ikko’,
‘Daushe Dan Ikko’,‘Sabo Dan Accra’ and ‘Daushe Dan Accra’ were obtained from Mariri kola
nut market (‘Yangoro), Kano. The moisture content of the four varieties of k
ola nut, C.
Cfor 48 hours and the
result was obtained as,30.58 ± 0.32, 20.80 ± 0.22, 36.62 ± 0.23 and25.16 ± 0.31% for ‘Sabo
’ respectively. The
dried samples were defatted using the Soxhlet apparatus and petroleum ether of 60
-80oC
boiling point and the following fat contents were obtained, 2.53 ± 0.25, 2.80 ± 0.03, 2.61 ±
kko’, ‘Sabo Dan Accra’ and
‘Daushe
respectively. The caffeine was extracted by the use of chloroform and the
contents were found to be, 600mg/20g (3.00%), 580mg/20g (2.90%), 540mg/20g (2.70%) and
n Ikko’, ‘Sabo Dan Accra’, ‘Daushe Dan
Accra’ respectively. The results showed that generally the Lagos varieties contain more
particularly Nigeria (Somadhi, 2004). Kolanut is
used as a religious object and scared offering
during prayers, ancestors’ venerations and
significant life events such as naming
ceremonies, weddings and funerals. It is also
aditional divination system called Obi
divination among the Igbo’s. For this purpose
kola nut divided in to four lobes is suitable. The
nuts are cast upon a special wooden board and
resulting patterns are read by a trained diviner.
currently enjoying
increased growth within the United State and
. Kola nut is preferred among African
Muslims who are forbidden to drink alcohol
). Chewing kola nut can ease
hunger pangs and is often used to treat
asthma (Steinegger and
Hansel, 1992). The caffeine present acts as a
bronchodilator, expanding the bronchial air
). However, frequent
chewing of the kolanut can lead to stained
Various medicinal and pharmacolog
ical
values have been observed in species of cola.
Fresh kola nuts have stimulant action apart
from the caffeine content, as they appear in
European commerce. Their action is
indistinguishable from that of other caffeine
drugs (Jayeola, 2001). Caffeine in
kola nut
works by stimulating the central nervous system
(CNS), heart and muscles (Ratsch, 2005).
http://dx.doi.org/10.4314/bajopas.v10i1.50S
Special Conference Edition, November, 2017
Medically, kola nut was found to have a marked
stimulating effect on the human consciousness.
In the short term, it may be used in nervous
debility in states of weakness, aid in states of
depression and may, in some people give rise to
euphoric states, because of its caffeine
content. Kolanut may relieve some migraine
headaches. The phenolics and anthrocyanin are
likely to provide antioxidant activity (Newall et
al., 1996). Kolanut increases the capacity for
physical exertion and for enduring fatigue
without food; stimulating a weak heart,
weakness, lack of emotion, depression, anxiety
and sea sickness (Daels-Rakotoarisonet al.,
2003). Kola nuts are also employed in the
treatment of malaria fever (Odugbemi, 2006).
Experiment using animals indicated, kolanut to
have analeptic and tripolytic properties and
stimulate the secretion of gastric juices (Grin,
2007). Traditionally the leaves, twigs, flowers,
fruit follicles and the bark of cola nitida and
cola acuminata are used to prepare a tonic as a
remedy for dysentery, coughs, diarrhea,
vomiting and chest complaints (Burkill, 1995).
Caffeine is solid with density 1.2g/cm
3
and slightly soluble in water, but soluble in
solvents like ethylacetate, chloroform,
pyrimidine, pyrrolee.t.c. Caffeine is
moderately soluble in alcohol and slightly
soluble in petroleum ether, ether and benzene.
It has a melting point of 273
o
C and a boiling
point of 178
o
C (Sublimes). The most commonly
used caffeine containing plants are coffee, tea,
kola and to some extent cocoa. Caffeine is one
of the world’s most widely used drugs. Many
anthropologists believe its use dated back to
the Stone Age. Near the end of the 19
th
century, cola products started to appear around
the world and become one of the larger drank
caffeine drinks (Jarvis and Martin, 1993).
Evidence of a risk to pregnancy is
equivocal, but some authorities have concluded
that prudent advice is for pregnant woman to
limit consumption to the equivalent of two cups
of coffee per day or less. Caffeine has diuretic
properties when administered to people who
are not used to it, but regular users develop a
tolerance to this effect, and studies have
generally failed to support the common notion
that ordinary consumption contributes
significantly to dehydration. With heavy use,
strong tolerance develops rapidly and caffeine
can produce clinically significant physical and
mental dependence (Mayo clinic, 2012).
Caffeine is toxic at sufficiently high doses.
Ordinary consumption can have low health
risks, even when carried on for years. There
may be a modest protective effect against
some diseases, including certain types of
cancer. Caffeine can have both positive and
negative effects on anxiety disorders. Some
people experience sleep disruption if they
consume caffeine, especially during the
evening hours, but others show little
disturbance and the effect of caffeine on sleep
is highly variable, (Peters and Josef, 1967).
This research is aimed at determining
and comparing the caffeine contents of the old
and fresh kola nut(Cola acuminate) from the
southern part of Nigeria referred to as ‘Dan
Ikko’ meaning the Lagos variety, while kola nut
from Ghana is the one referred to as ‘Dan
Accra’. Old kola nut is called ‘Daushe’ and the
fresh is ‘Sabo’, while Lagos is called ‘Ikko’ all
by the Hausas, who are known to be the major
kola nut consumers in Nigeria. This can be
referred to a saying thus, ‘kola nut, produced
by the Yorubas, celebrated by the Igbos and
eaten by the Hausas.’
MATERIALS AND METHODS
Four samples of Kola nut (C.
acuminate) comprising of two Nigerian kola
nuts, “Goro Sabo Dan Ikko” or Lagos fresh Kola
and “GoroDaushe Dan Ikko” or Lagos old Kola
and the other two being foreign, Ghana kola
nuts, “Goro Sabo Dan Accra” or Accra fresh
Kola and “GoroDaushe Dan Accra” or Accra old
Kola were obtained and identified at Mariri Kola
nut Market (‘Yan goro’), Kano, Nigeria.
Determination of Moisture and Fat Contents
The four samples of kola nut were
grated and driedin an oven at temperature of
105
o
Cto obtain their moisture contents. They
were then ground into fine powder and placed
into an air tight container before further
processes. The dried kola nut (C. acuminate)
samples were defatted by using Soxhlet
apparatus and petroleum ether of boiling point
range of 60-80
o
C as the extraction
solvent.5.00g of each dried sample in triplicate
were defatted and the average calculated.
Determination of Caffeine Content
Caffeine content was determined
according to Irgolic et al. (1982) methods. 20g
of each of the dried and defatted kola nut
samples was placed into a 250ml round bottom
flask and 150ml de-ionised water was added to
each. The mouth of each flask was connected
to a refluxing system. Each of the flasks was
placed into a heating mantle with a regulated
temperature. As soon as the content begins to
boil the tap of water was opened to allow
draining the water out of the condenser and
the sets were allowed to reflux for one hour.
The refluxing system was turned off and
allowed to cool for about thirty minutes. After
cooling, the refluxed was sieved out of grated
kola nut (with 0.1mm and 0.2 mm sieve) into a
250ml beaker.
248
Special Conference Edition, November, 2017
The residues were discarded and the filtrate was retained and placed in ice block for 15 minutes.
Then 150ml of the filtrate were placed into a
500ml separating funnel and 150ml of
chloroform added gradually. The corked
separating funnel was shaken until the
chloroform, water interface was established.
After two hours a clear solution was formed
into which caffeine dissolved in chloroform.
The caffeine chloroform solution was then
transferred into a 250ml beaker and the
chloroform evaporated over a water bath
(Esther et al., 2005) leaving yellowish white
caffeine crystals.
The crude caffeine obtained was
purified by recrytallisation in toluene. In this
5ml of toluene was added onto the crude
caffeine crystals in a 50ml beaker and heated
on hotplate for the caffeine to dissolve. When
the crude caffeine dissolved, the beaker was
removed from the hotplate, 10ml of petroleum
ether (60-90
0
C) was added and the caffeine
allowed to crystallise (Okoliet al., 2012). The
weight of the resultant pure caffeine crystals,
now white was taken on a Mettlerelectric
balance.The final product was confirmed as
caffeine by thin layer chromatography (TLC)
test and melting point determination.
RESULTS AND DISCUSSION
Moisture Content
The results obtained are as shown in Tables I, 2
and 3 below. Table 1 shows the mean moisture
contents of the four varieties of kola nut (C.
acuminate).
Table 1: Mean Moisture Contents of the Kola nut (C. acuminate) Samples
S/N
KOLANUT SAMPLE
MEAN MOISTURE CONTENT (%)
1
2
3
4
Sabo Dan Ikko (SDI)
Daushe Dan Ikko (DDI)
Sabo Dan Accra (SDA)
Daushe Dan Accra (DDA)
30.58 ± 0.32
20.80 ± 0.22
36.62 ± 0.23
25.16 ± 0.31
As shown in Table 1 above, the kolanut samples
generally have high moisture contents. The
results showed that ‘Goro Dan Accra’ (fresh and
old) is having higher moisture content than its
counterpart ‘Goro Dan Ikko’. For both ‘Goro
Dan Ikko’ and ‘Goro Dan Accra’, ‘Goro Sabo’
(fresh) has higher moisture content than
‘GoroDaushe’ (old). This is not surprising,
because ‘GoroDaushe’ (old) was exposed for a
longer period to air, therefore being dryer than
‘Goro Sabo’ (fresh) with shorter exposure.
However, the moisture content of kolanut
(fresh or old) generally depends on how it is
taken care of in terms of exposure to air. This
is why possibly the water contents of all the
samples in this work are much lower than that
of C. nitida obtained in Odebunmi et al, (2008)
as 66.4%, but very much higher than that of
Dewole et al (2013), who reported the moisture
content of both C. acuminate and C. nitida to
be in the range of 9.73-9.81%.
Fat Content
Table 2: Mean Fat Contents of the Kola nut, C. acuminate Samples
S/N
KOLANUT SAMPLE
MEAN
FAT
CONTENT (%)
1
2
3
4
Sabo Dan Ikko (SDI)
Daushe Dan Ikko (DDI)
Sabo Dan Accra (SDA)
Daushe Dan Accra (DDA)
2.53
± 0.
2
5
2.80 ± 0.30
2.61 ± 0.35
2.72 ± 0.22
From Table 2 above, kola nut generally has low
fat content and this result also shows that the
old or “GoroDaushe” has higher content of the
fat compared to fresh or “Goro Sabo” and
“GoroDaushe Dan Ikko” has higher fat content
that that of “GoroDaushe Dan Accra”, while it
is the other way round in the case of the fresh
kola nut or “Goro Sabo”. The fat content
determined in this work is in line with Dewole
(2013) finding that obtained a range of 2.20 –
3.02%.
249
Special Conference Edition, November, 2017
Caffeine Content
Table 3: Amount of Caffeine in the Kola nut, C. acuminate Samples
S/N
K
OLANUT SAMPLE
MEAN CAFFEINE CONTENT (%)
1
2
3
4
Sabo Dan Ikko (SDI)
Daushe Dan Ikko (DDI)
Sabo Dan Accra (SDA)
Daushe Dan Accra (DDA)
3.00 ± 0.12
2.90 ± 0.15
2.70 ± 0.13
2.50 ± 0.20
The mean caffeine content of the four
different samples of Kola nut are as shown in
Table 3 above. It can be observed from the
results that varieties of kola nut have different
caffeine contents as in Esther et al, (2005). As
shown in Table 3, ‘Goro Sabo Dan Ikko’ contains
averagely 600mg of caffeine per 20g (3.00%),
while ‘Goro daushe Dan Ikko’ has averagely
580mg per 20g (2.90%). Again, ‘Goro Sabo Dan
Accra’ contains averagely 540mg of caffeine
per 20g of kola nut (2.70%), while ‘Goro daushe
Dan Accra’ contains only an average of 500mg
caffeine per 20g of kola nut (2.50%). This shows
that ‘Goro Sabo’ (fresh) from both Ikko
(Nigeria) and Accra (Ghana) contain higher
amount of caffeine than ‘Gorodaushe’ (old).
The results also showed that both ‘Goro
Sabo Dan Ikko’( fresh) and ‘Goro Sabo Dan
Accra’ (fresh) varieties of kola nut used in this
work have much higher average caffeine
contents of 3.00 and 2.70% respectively
compared to the those of Jayeola, (2001) with
caffeine content of 1.50% for fresh kola nut,
South, (2017), 1-1.5%, BHF (2017), 1.5-2.0%,
while Lowrence (2014), estimated it as 2.0%.
AHS (2017), published the caffeine content of
kola nut to be 2-3.5%, which is in line with the
results obtained in this work. However, Okoli
et al (2012), obtained the caffeine in K.
acuminate as 4.7% which is much higher than
even those of ‘Goro Sabo Dan Ikko’ and ‘Goro
Sabo Dan Accra’ samples of this work.
From the results ‘Goro Dan Ikko’
(Nigeria), both Sabo (fresh) and ‘Daushe’ (old)
have higher percentage of caffeine compared
to the ‘Goro Dan Accra’ (Ghana), both Sabo
(fresh) and Daushe (old). The differences in
caffeine contents may be due to climatic
factors and edaphic factor of the kola nut
(Aheme et al., 2009). According to these
authors, these factors can cause serious
variation in nutritional properties of the kola
nut, which therefore includes the caffeine
content.
CONCLUSION
From the results, ‘Goro Sabo’ (fresh)
has higher moisture content than ‘Goro Daushe’
(old) for both ‘Goro Dan Ikko’ (Nigeria) and
‘Goro Dan Accra’ (Ghana), although the
difference is not all that much.However, there
is much difference between the values
determined in this work and others; some much
higher and much lower for some. This shows
that moisture content of kola nut in general
depends on, freshness, the nature of storage or
exposure to air.
The fat content of kola nut, C.
acuminate is generally very low and averagely
similar for all the four varieties as compared to
other nuts like ground nut with much higher
content.The experimental results have shown
that the caffeine content in different kola nut
varies. It was found that ‘Goro Dan Ikko’
(Nigeria), both fresh and old, has higher
caffeine content compared to its counterpart
‘Goro Dan Accra’ (Ghana), both fresh and old.
It can also be concluded from this work that
kola nut contains caffeine as 2.5-3.0% of its dry
matter. The caffeine content of kola nut can
also differ with difference in the soil it is grown
in, climatic and adaphic factors.
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