The
result of the preliminary Phytochemical screening of aqueous methanolic stem
bark extract of Acacia polyacantha
revealed the presences of Alkaloids, Anthraquinones, Cardiac glycosides,
carbohydrate, Flavonoids, Glycosides, Triterpenes, Saponins, Tannins. As shown.
Screening
|
Test
|
Observation
|
Inferences
|
Alkaloid
|
Mayer’s test
Dragendoff’s test
Wagner’s test
|
Cream precipitate
Red precipitated
Whitish precipitate
|
Positive
Positive
Positive
|
Antraquinones
|
Free anthraquinones (Botrager’s test)
Combine antraquinones
(modifiedBotrager’s)
|
No colour change
A yellow colour change
|
Negative
Positive
|
Cardiac glycosides
|
Kelle- Killiani test
Kadde
test
Salkwoskis test
|
Purple ring was seen at the interface
A reddish colouration
A reddish brown ring at the interface
|
Positive
Positive
Positive
|
Carbohydrate
|
Molish’s test
Fehling test
|
Purple violet ring was seen at the
interface
Brick red precipitate
|
Positive
Positive
|
Flavonoids
|
Shinoda’s test
NaOH
|
Red colour was seen
Yellow colouration
|
Positive
Positive
|
Saponins
|
Frothing test
|
A honey comb was formed which persist
for more than thirty minutes
|
Positive
|
Steroids & Triterpenes
(Liberman Burchard’s test)
|
Steroid
triterpenes
|
No green colour seen
Red colouration was formed
|
Negative
Positive
|
Glycoside
|
Fehling test
Ferric test
|
Brick red precipitate was formedBlue
black precipitate
|
Positive
Positive
|
Acute oral toxicity
The LD50 was
determinated using the method of Lorke (1983). In the initial phase, male
Wistar rats were divided into three groups of three rats each. They were
treated with the aqueous stem
bark extract of Acacia polyacantha at doses of 10 mg/kg, 100 mg/kg and
1000 mg/kg per orally. The animals were monitored
for signs of toxicity over 24 hours. There was however, no case of mortality
after the elapse of the period as shown in table two. In the second phase, 3
rats were divided into three groups of one
rat each .They were treated with the aqueous stem bark extract of Acacia
polyacantha at doses of 1600 mg/kg, 2900 mg/kg, and 5000 mg/kg per orally. These
groups were also monitored for 24 hours with mortality recorded as seen in
table three. Signs of toxicity were first observed 2-3 hours after extract
administration. These signs of toxicity observed include: convulsion,
restlessness which subsequently led to insensitivity to touch and finally
death. The LD50 was calculated to be 3807.9 mg/ kg by the log-probit
using the method of Miller and Tainter (Lorke, 1983).
Table:
percentage mortality of different doses of extract of Acacia polyacantha
stem bark extract administered to Wistar rats at the first phase of acute
toxicity studies.
GROUPS
|
DOSES(mg/kg)
|
NO. OF RECORDED DEATHS
|
% MORTALITY
|
1
|
10
|
0/3
|
0
|
2
|
100
|
0/3
|
0
|
3
|
1000
|
0/3
|
0
|
Table:
percentage mortality of different doses of Acacia polyacantha stem bark
extract administered to Wistar rats at the second phase of acute toxicity
studies.
GROUPS
|
DOSES (mg/kg)
|
NO. OF RECORED DEATHS
|
% MORTALITY
|
1
|
1600
|
0/1
|
0
|
2
|
2900
|
0/1
|
0
|
3
|
5000
|
1/1
|
33.3
|
Mounting
frequency
The mounting frequency was found to be 8.40 ± 3.25;
3.8 ± 1.35 and 0.20 ± 0.20 mounts/3 hrs of the three doses 150, 300, and
600mg/kg of the aqueous methanolic stem bark extract of Acacia polyacantha,
the extract treated group did not show significant (p>0.05) increase in the mounting frequency when compared to
those of control which is 6.20 ± 2.249
mounts/3hrs, and Viagra 5mg/kg which is 6.60
± 2.78 mounts /3 hrs see table 4.4 below.
Testosterone
The serum testosterone
level are 6.88±1.72; 7.18 ± 2.35 and 7.72 ±2.38ng/ml of the three doses 150, 300, and 600mg/kg of the aqueous
methanolic stem bark extract of Acacia polyacantha, did not show
significant increase (p>0.05) in serum testosterone when compared with 3.62
± 2.19, 3.60±1.34ng/ml of control and Viagra 5mg/kg see table 4.4 below.
Sperm count
The result of
the sperm count 32.80 ±1.88; 25.60 ±2.63; and 22.00 ± 0.94mil/cell of the three
doses 150, 300, and 600 mg/kg of the aqueous methanolic stem bark extract of Acacia
polyacantha, the extract treated group did not show significant (p>0.05)
increase in sperm count when compared to 26.6 ± 0.94, 22.0 ± 2.13 mil/cell of control
and Viagra 5mg/kg see table 4.5 below.
Sperm
motility
The sperm motility of the three doses 150, 300,
and 600mg/kg of the aqueous methanolic stem bark extract of Acacia
polyacantha were found to be 66.00 ±
2.75; 59.60 ± 4.95; and 57.40 ± 4.73%
respectively, when compared with 66.00±2.75; and 53.00 ±3.40% of control,
and Viagra 5mg/kg did not show significant (P>0.05) increase in sperm motility see table 4.5 below.
Sperm
morphology
A significant
increase (p<0.05) in the results 66.00 ± 2.31; 62.60 ±4.46; and 59.20 ± 3.56%
of the three doses 150, 300 and 600mg/kg of the aqueous methanolic stem bark
extract of Acacia polyacantha, was seen in normal sperm morphology when
compared with 41.60 ±3.93% of Viagra 5mg/kg treated group as shown in table 4.5
below and figure 4.1.
Histological
analysis
The result in plate 4.1 shows the result
of the control, plate 4. 2 shows Viagra treated group, plate 4.3, 4.4 and 4.5 showed
the results of 150, 300 and 600 mg/kg body weight treated groups respectively.
The control group showed a well defined
seminiferous tubules, and the spermatogenic cells up to the spermatids are well
define.
The Viagra group appear to have an
increased amount of elongated spermatids arising from the secondary
spermatocytes toward the lumen of the
seminiferous tubules.
The groups that were treated with the
doses of 150, 300, and 600mg/kg of the extract had a reduced number of primary
spermatocytes, with increase in the number of spermatids toward the lumen of
the seminiferous tubule.
Table
showing the result of mounting behavior, and serum testosterone
Groups
|
Mounting frequency
(3 hours)
|
Serum testosterone (ng/ml)
|
Control
|
6.20±2.49
|
3.62±2.19
|
Viagra (5mg/kg)
|
6.60±2.78
|
3.60±1.34
|
150mg/kg
|
8.40±3.25
|
6.88±1.72
|
300mg/kg
|
3.80±1.35
|
7.18±2.38
|
600mg/kg
|
0.20±0.20
|
7.72±2.38
|
Table showing the result of sperm count, sperm motility, and sperm morphology
Groups
|
Sperm
count×106
Cells.ml(concentration)
|
Sperm
motility(%)
Motile
|
Sperm
morphology(%)
Normal.
|
Control
|
26.60±0.94
|
66.00±2.75
|
63.00±1.34
|
Viagra
(5mg/kg)
|
22.20±2.13
|
53.00±3.40
|
41.60±3.93
|
150mg/kg
|
32.80±1.88
|
66.00±2.75
|
66.00±2.31*
|
300mg/kg
|
25.60±2.63
|
59.60±4.95
|
62.60±4.46*
|
600mg/kg
|
22.00±0.94
|
57.40±4.73
|
59.20±3.56*
|