Using four different experimental models of normal and diabetic male albino rats, blood sugar lowering efficacy of Momordica charantia Linn. of the family Cucurbitaceae has been assessed. Ethanolic (95%) extract of the whole plant of M. charantia significantly lowered blood sugar in fasted, fed and mild diabetic male albino rats at a single oral dose of 250mg/kg that has not been reported earlier. This extract also depressed the peak value significantly in the glucose loaded model.

2. J. Appl. Biosci., 33(2): 153-155, December, 2007 ISSN 0379-8097
EFFECT OF ETHANOLIC EXTRACT OF MOMORDICA CHARAN,TIA ON BLOOD
SUGAR LEVEL IN NORMAL AND STREPTOZOTOCIN INDUCED DIABETIC RATS
RAHUL GUPTA, SHASm KANT2
, SAMTA JOHRII and A.M. SAXENA *
*Department of Zoology, University of Lucknow, Lucknow-226 007, U.P., India
'Department of Zoology, Mahila Girls P.G. College, Lucknow, U.P.,India
2Departmentof Zoology, S.D.P.G. College, Math-Lar, Deoria, U.P., India
ABSTRACT
Using four different experimental models of normal and diabetic male albino rats, blood sugar
lowering efficacy of Momordica charantia Linn. of the family Cucurbitaceae has been assessed.
Ethanolic (95%) extract of the whole plant of M. charantia significantly lowered blood sugar in
fasted, fed and mild diabetic male albino rats at a single oral dose of 250mglkg that has not been
reported earlier.This extract also depressed the peak value significantlyin the glucose loaded model.
KEY WORDS: Blood sugar, Diabetes mellitus, Ethanol extract, Momordica charantia,
Streptozotocin
INTRODUCTION
Diabetes mellitus is the most cornmon of the metabolic
disorders and represents a global health problem. Plants
and herbs have been used, since long, in India for the
treatment of diabetes mellitus (Mukherjee, 1981; Mukherjee
et al., 2006; Gupta et al., 2006). The cornmon belief that
bitter principles from the plants of Cucurbitaceae family
are potent blood sugar lowering agents has not been
authenticated (Chandrasekhar et al., 1989). However,
various other medicinal properties have been attributed
to the plants of this family (Sastri, 1962).
Momordica charantia Linn. (Family: Cucurbitaceae)
is a monoecious climber, cultivated throughout India as a
vegetable. The fruits are stomachic and used in gout,
rheumatism and diseases of spleen and liver. The fruits
and leaves are used as anti-helminthic and vermifuge and
also in piles and jaundice. Fruit, leaves and roots.are also
used as a folk remedy for diabetes mellitus (Nadkarni, 1976;
Satyavati et al., 1987). Different parts of M. charantia
have been regarded as blood sugar lowering agents from
time to time (Mukherjee, 1981; Kar et al., 2003; Zhang et
al., 2005; lung et al., 2006). However, observations of some
have been disputed by others and trials carried out on M.
charantia have revealed lacunae except in rare instances
(Gupta & Seth, 1962; Bever & Zahand, 1979; Khanna et
al., 1981; Krawinkel et al., 2006; Harinantenaina et al.,
2006). These conflicting observations led us to
reinvestigate the possible blood sugar lowering activity
of 95% ethanol extract of the whole plant of M. charantia
in male albino rats.
MATERIALS AND METHODS
Plant material was collected during the fruiting season
from Bareilly district, U.P., India. The Department of
Botany, University of Lucknow, Lucknow provided active
help in the pharmacognostic study. International guidelines .
(Harnischfeger, 2000) were followed for the collection of
plant materials, which were dried in shade and grinded
mechanically. The coarse powder was used for extraction
and the extract was prepared in 95% alcohol (ethanol) with
the help of soxhlet.
Charles foster strain male albino rats (120-l40g) were
used. Animals were maintained on standard pellet diet,
housed in polypropylene cages at a temperature of 22-23
± 2°C and relative humidity 60 ± 5. Water was allowed ad
libitum. The colony of rats was acclimatized to laboratory
conditions prior to experiments and then randomly divided
in to eight groups of six animals each. The dose of plant
extract was prepared in 2% gum acacia as suspension and
was fed by metal canula attached to a glass syringe at a .
single dose of 250mg/kg body weight to experimental
group. Control group was fed only 2% gum acacia
suspension.
*Correspondingauthor;E-mail: anandmsaxena@rediffmail.com; Tel.: 09415028759,0522-2357057 (Resi.)
153

3. J. Appl, Biosei., 33(2)
Table-I: Effect of 95% ethanolic extract of Momordica charantia at a single dose of 250 mg/kg body weight, orally,on blood sugar
level of fasted, fed and streptozotocin induced mild diabetic albino rats
Treatment Blood sugar level mg/l00rnl (Mean ± S.E.) at time (hours)
Group
Oh 1h 3h 4h
78.49±2.05 (6)
73.33±1.84 (6)
Maximum %of
blood sugar
lowering from
initialvalue
Fasted Control
M. charantia
Whole plant
Control
M. charantia
Whole plant
Diabetic Control
M. charantia
Whole plant
Significance between the control and experimental group: *P<0.05, **P<O.Ol, ***P<O.OOl
In parenthesis the number of rats used is given.
84.72±4.26 (6)
81.00±1.35 (6)
83.55±2.43 (6)
71.43±1.28** (6)
Fed 90.75±1.68 (6)
93.96±1.58 (6)
93.56±0.78 (6)
97.74±3.01 (6)
203.61±13.36 (6) 224.78±14.40 (6)
198.25±10.67 (6) 169.00±I1.42* (6)
79.46±2.26 (6)
63.24±1.85*** (6)
7.35% at 4 h
21.92% at 3 h
93.75±1.58 (6)
76.33±3.06*** (6)
No lowering
18,76% at 3 h
91.26±2.00 (6)
85.31±2.18 (6)
230.55±11.39 (6)
144.22±5.28*** (6)
213.83±13.26 (6)
126.39±4.15***(6)
No lowering
36.24% at4 h
Tab1e-2: Effect of 95% ethanolic extract of Momordica charantia at a single dose of 250mg/kg body weight, orally, on glucose
tolerance (l500mg/kg b.w.orally) of albino rats
Treatment Blood sugar level mg/lOOrnl(Mean ± S.E.) at time (hours)
Group
1h
112.91±4.64 (6)
82.39±2.97*** (6)
3h
99.67±3.37 (6)
79.26±2.32***(6)
Maximum % of
blood sugar
rise from
initialvalue
Glucose Control
Loaded M. charantia
Whole plant
Significancebetween the control and experimental group: *P<O.05, **P<O.Ol, ***P<O.OOl
In parenthesis the number of rats used is given.
Oh
74.33±2.06 (6)
70.56±2.44 (6)
1/2h
120.02±4.75 (6)
96.04±2.86** (6)
Four models were used for experimental evaluation.
1. Fasted: The blood was collected from the tail vein
of the overnight (I8h) fasted male albino rats, before and
at 1, 3, 4 h after the crude extract administration. Blood
sugar was estimated in vitro by Nelson's Somogyi Method
(Nelson, 1944).
2. Fed: The experiments were carried out on fully fed
rats, following the same procedure as in fasted model.
3. Glucose loaded: From the overnight (18 h) fasted
rats blood samples were collected at 0 h, and extract was
administered. After half an hour a single dose of glucose
solution (I500mg/kg) was given and blood samples were
again collected for in-vitro sugar estimation at 1/2, 1 and
3h.
4. Diabetic: The mild diabetic model was prepared by
streptozotocin (Sigma Lab., U.S.A.) injection at a dose of
35mg/kg through the tail to overnight (18 h) fasted rats.
Streptozotocin was dissolved in chilled citrate buffer (pH
4.5). After 48 h of streptozotocin injection diabetic rats
(blood sugar level >140mg/lOOml) were selected by using
diastex (Saxena et al., 1991). Further experiment was
61.46% at 1/2 h
36.11% at 1/2h
performed using identical protocol as in fasted model.
The analysis for significance was determined
separately for each time period in each model. From the
data, Mean and Standard Error (S.E.) were determined and
the individual comparisons (between the groups) were
done by Student's 't' test.
RESULTS AND DISCUSSION
Chandrasekhar et al. (1989) reported that 95% ethanol
extract of M. charantia (whole plant) caused significant
(P<O.Ol) blood sugar lowering in fasted model only at 3
h. In the present work a definite blood sugar lowering
effect was observed at I h (P<O.Ol) and 3 h (P<O.OOl) as
compared to corresponding control (Table 1). Maximum
blood sugar lowering calculated in terms of percentage
from the initial value was higher (21.92% at 3 h) in
comparison to 2% gum acacia (7.35% at 4 h).
Ethanolic extract of whole plant produced very
significant (P<O.OOl) blood sugar lowering, at 3 h in fed
group of rats. Maximum percentage of blood sugar
lowering was 18.76% at 3 h but there was no blood sugar
lowering in the control group (2% gum acacia).
154

4. J. AppI. Biosci., 33(2)
There was slight but significant (P<O.05) lowering at
1h and very significant lowering at 3 h (P<O.OOl) and 4 h
(P<O.OOl) in mild diabetic rats. Blood sugar lowering was
36.24% at 4 h and there was no blood sugar lowering in
control group.
M. charantia (whole plant) extract produced
significant suppression of peak value at 1/2 h (P<O.Ol), 1
h (P<O.OOl) and 3 h (P<O.OOl) when compared to
corresponding control (Table 2). Assessed from the
maximum percentage of blood sugar rise it was 36.11 % at
1/2 h in the treated group and 61.46% at 1/2 h in the control
group.
It is concluded that 95% ethanol extract of M.
charantia (whole plant) significantly lowered blood sugar
in different experimental male albino rat models along with
significant depression of peak value in glucose loaded
model, not reported earlier. This could probably be due to
the interplay of alterable parameters, like collection of plant
material, time of collection, extraction procedure, dose and
form of extract. Further investigations on M. charantia
are needed to search out the probable mechanism of its
action for blood sugar lowering.
ACKNOWLEDGE:MENT
Authors are thankful to Prof. NirupamaAgarwal, Head,
Department of Zoology, University of Lucknow, Lucknow
for her keen interest and constant encouragement in the
work. We are also thankful to Department of Botany,
University of Lucknow, Lucknow for their active assistance
in the identification of plant material.
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