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ISSN: 2229-3787
Journal of Advanced Pharmaceutical Research. 2011, 2(3), 128-134.
Research paper
Isolation and evaluation of Vigna mungo gum as a novel binder
Hemant H Gangurde*, Mayur A Chordiya, Bhushan P Chordiya, Harish R Lukkad, Nayana S Baste, Vijay S Borkar
Department of Pharmaceutics, SNJB’s Shriman Suresh Dada Jain College of Pharmacy, Neminagar, Chandwad,
Nasik, Maharashtra,India.
Corresponding author E.Mail: hhgangurde@gmail.com
Received: Apr 18, 2011; Accepted: June 06, 2011
ABSTRACT
India is gifted with great abundant variety of flora and fauna. Today, the whole world is increasingly interested in
natural drugs and excipients. Natural materials have advantages over synthetic materials because they are non toxic,
less expensive and freely available. Various gums like gelatin, acacia, alginic acid, guar gum, maize starch, and
potato starch have been used as binder in pharmaceutical formulations. But still finding novel binder is useful in the
pharmaceutical industry for manufacture of tablets. The present study was undertaken to find out the potential of
gum extracted from Vigna mungo seeds as a binder in tablet formulations. Paracetamol was selected as model drug
for this study. The gum was extracted from the seeds, and evaluated for solubility and flow properties. Gum was
used as a binder at variant concentrations of 6, 8 and 10% w/v. The paracetamol tablets formulated using Vigna
mungo seed gum (VMSG) were evaluated for general appearance, thickness, content uniformity, hardness,
friability, disintegration time and drug release profile. Paracetamol tablets containing gelatin as standard binder
were prepared and assessed comparatively. Results obtained indicate that VMSG performed as good as gelatin as a
binder to paracetamol tablets.
KEYWORDS: Binder, Vigna mungo seed gum, Paracetamol, gelatin.
INTRODUCTION
Binders are agents used to impart cohesive
qualities to the powdered material during the production
of tablets. They impart cohesiveness to the tablet
formulation, which ensures that the tablet remains intact
after compression as well as improving the free flowing
quality (Sujja et al., 1996). Binders have been used as
solutions and in dry form depending on the other
ingredients in the formulations and the method of
preparation. The choice of a particular binding agent
from different sources have been evaluated and used
as excellent binders in either mucilage or the dry
powdered form (Kulkarni et al., 2002; Panda et al., 2006;
Ibezim et al., 2008).
Apart from starches, other natural
gums, gelatin, sugar solutions, modified natural and
synthetic polymers have been employed with
considerable success as binders. In all evaluations,
the type and binder concentrations have direct effect
on the crushing strength, friability, disintegration
time and tablet dissolution (Mahajan et al., 1988).
depends on the binding force required to form granules
Polymers of natural origin are more
and its compatibility with the other ingredients
economic as compared to synthetic/ semi synthetic
particularly the active drug (Panda et al., 2008). Starches
polymers. Owing to these characteristics of the
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natural
excipients
their
use
in
pharmaceutical
formulations is much desirable. Black gram (Vigna
mungo) also referred to as the Urad bean, Urad, urid,
black gram, black lentil or white lentil is a bean grown in
southern Asia. It is food legume and belongs to family
Leguminoseae. The seed flour of Black gram swells and
form gelatinous mass when it comes in contact with
water due to its hydrophilic nature. It is used as a binder
in the preparation of batter for cooking “Imarti
(Jahangiri)” in south India (Mahajan et al., 1988). Under
the Mughals in South Asia, sometimes in the building of
bridges use was made of lentils/daals such as Urad daal
which is a sticky daal and acted as a binder and
strengthening material due to large quantity of
polysaccharides (Yadav et al., 2009). These wide
applications of seed flour of Black gram propose their
strong hydrophilic nature, substantial binding property
ISSN: 2229-3787
Extraction of gum (Yadav et al., 2009)
Vigna mungo seeds were roasted at 70°C for
10 min to make the shell brittle. The seeds were then
dehusked and the cotyledons were autoclaved in a
1% (m/V) solution of sodium metabisulphite at
121°C for 15 min. This helps inactivate the enzymes
usually present and also reduces darkening. The
cotyledons were then air dried, pulverized in a
hammer mill and the flour obtained was soaked in a
solution of 1% (m/V) sodium metabisulphite for 24 h
and thereafter passed through a muslin cloth. The
resultant filtrate was desolvated with acetone. This
product of desolvation (VMSG) was dried in a hot
air oven (Labin LI87D, India) and then pulverized.
This gum and gelatin powder was tested for flow
properties and the values were represented in table 1.
All values were found to be satisfactory.
and compatibility with the physiologic environment.
Since matrix tablet is the easiest approach to design the
Solubility determination (Tsige et al., 1993)
sustained drug delivery system, we were interested in
A 2% w/w dispersion of gum was prepared
investigating the matrix forming ability of seed flour of
in a 50 ml volumetric flask. The dispersion was
Black gram in tablets for sustained drug delivery (Tsige
shaken frequently for some time and allowed to
et al., 1993).
stand for about 8 h. It was then filtered with a filter
MATERIALS AND METHODS
paper and 30 ml of the clear filtrate evaporated to
dryness in a preweighed dry crucible. The weight of
Materials
The seeds of Vigna mungo (Black gram) were
purchased from local market. Paracetamol was used as a
model drug in the study, and it was a kind of gift sample
gum residue obtained was determined by difference.
Solubility was calculated in g/dm3 and mg %. The
same procedure was repeated for gelatin powder.
Bulk and tapped densities (Schwartz et al., 1975)
from Haffkine Ajintha Pvt. Ltd., Jalgaon. All the
chemicals and other reagents used in the study were of
AR grade.
A 20.0 gm bulk volume sample of VMSG
powder was transferred into 100 ml measuring
cylinder and the volume, which was the mean of the
reading from several sides, was calculated. The
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ISSN: 2229-3787
cylinder was tapped for 250 times when there was no
The angle of repose of powdered gum was
observable decrease in volume. The bulk and tapped
determined by the funnel method. The accurately
densities were calculated as the mean of three
weighed gum powder was taken in a funnel. The
determinations from the equation:
height of the funnel was adjusted in such a way that
p= m/v
Where p is density (g/cm3), m is the mass ( g ) of
the data gum, v is the volume of the powder in the
cylinder.
the tip of the funnel just touched the apex of the
heap of the powder. The powder was allowed to
flow through the funnel freely onto the surface. The
diameter of the powder cone was measured and
angle of repose was calculated using the following
Compressibility (Carr’s) Index
equation:
θ = tan –1 (h/r)
The simplest method of measurement of free
flow of powder is compressibility, an indication of the
ease with which material can be induced to flow is given
Where “h” and “r” are the height and radius
of the powder pile respectively.
by compressibility index (I) which is calculated as
Preparation and evaluation of the granules
follows,
ρ − ρb
I= t
× 100
ρt
ρ t indicates the tapped density; ρ b indicates the
bulk density. The value below 15% indicates a powder
which usually gives rise to excellent flow characteristics,
whereas above 25% indicate poor flowability.
Hausner’s Ratio (H)
Aqueous solution of VMSG and gelatin in
the concentrations of 6, 8 and 10 % w/v, were
prepared with the aid of heat.
Paracetamol and starch (as a diluent) were
passed through sieve # 40 and mixed for 20 minutes
using laboratory scale double (twin) cone mixer.
Granules were prepared by wet granulation method
using VMSG and gelatin solutions in concentration
This is an indirect index of ease of powder flow.
It is calculated by the following formula,
Η=
ρt
ρb
of 8, 10 and 12 % w/v, the damp mass was passed
through sieve # 12 and granules were dried at 500 for
1hour in a tray drier. The dried material was then
passed through sieve # 16. The prepared granules
were then evaluated for moisture content analysis
ρ t indicates the tapped density; ρ b indicates the
and flow properties (by measuring angle of repose).
bulk density. Lower Hausner’s ratio (<1.25) indicates
The bulk and tapped densities were determined
better flow properties than higher ones (>1.25).
using bulk density apparatus. Compressibility index
of
Angle of repose (Liberman et al., 1989)
the
granules
was
determined
by
Carr’s
compressibility index.
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The disintegration time of tablets was
Formulation of Paracetamol Tablets
Magnesium stearate, talc and Aerosil 200 were
mixed with prepared granules (Table 3). These granules
were punched to tablets using eight station 2D Rimek
Minipress tablet compression machine (Karnavati
Engineering Ltd.) at arbitrary pressure load unit of 6
ISSN: 2229-3787
determined according to the method described in the
British Pharmacopoeia 1998. Six tablets were placed
in each compartment of the disintegration apparatus,
with water thermostated at 37 ± 10 C as the medium.
The tablets were considered to have passed the test
after the 6 tablets passed through the mesh of the
tons.
apparatus withinin 15 minutes.
Evaluation of compressed tablets (Banker et al., 1987;
Jaimini et., 2007)
Dissolution Tests
Drug release from different formulated
The prepared tablets were evaluated for weight
uniformity, hardness, thickness, friability, disintegration
time, and assay.
tablets was performed using USP XXII, type II
apparatus. 900ml of 0.1 N HCl was dissolution
medium; paddle was rotated at 75 rpm with bath
Thickness
temperature of 37 ± 10. At every 10 minutes interval
The thickness of the tablets was determined
5 ml of sample was withdrawn from the dissolution
using a Vernier caliper (Vashishat, Ambala Cantt.,
medium to maintain the volume constant. After
Haryana, India). Five tablets from each batch were used
filtration and appropriate dilution, the sample
and average values were calculated.
solutions were analyzed at 243 nm using a UV
Uniformity of Weight
Visible spectrophotometer. The amount of drug
present in the samples was calculated.
To study weight variation, 20 tablets of each
formulation were weighed using an electronic balance
RESULTS AND DISCUSSION
(Shimadzu D455003609, Japan) and test was performed
Comparative evaluation of VMSG with gelatin
according to the official method.
powder
Hardness and Friability
For each formulation, the hardness and friability
The
percentage
Vigna
of
gum
mungo
using
seeds
yield
acetone
as
high
gum
of tablets equivalent to 6.5g were determined using the
precipitating solvent. The isolated gum and gelatin
Monsanto hardness tester (Rolex, Chandigarh, India) and
powder
the Roche friabilator (Electrolab friabilator EF1W,
physicochemical properties as per Pharmacopoeial
Mumbai, India), respectively.
guidelines. The specifications were set and the
was
characterized
for
various
results are shown in Table no. 1. The VMSG
Disintegration time
exhibited a comparatively lower solubility than
gelatin powder in cold water with values of 10.35
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ISSN: 2229-3787
and 12.76 g/dm3respectively. The solubility result shows
the range of 200 to 280 which indicate free flowing
that both excipients are comparable. Interestingly there
properties of granules. The moisture content of all
is positive correlation between gum solubility and their
formulations observed within limits (Table 2).
binding/disintegrating efficiency in tablets. The low bulk
Evaluation of tablet (Table 4)
and tapped densities of both gelatin and VMSG indicate
that both materials are not highly porous and are poor
flowing powders. The non-free flowing nature of gelatin
and VMSG were observed from the fact that their
Hausner’s ratio of 1.21 and 1.27 respectively are greater
than 1.2 which indicate low inter particulate friction in
powder.
However,
VMSG possessed
better flow
properties than gelatin with Carr’s compressibility index
of 13.88 and 15.33% respectively (Table 1).
Three batches of tablets were prepared (as per
formulae given in Table 3) using isolated gum of
vigna mungo seed and gelatin powder at three
different concentrations 6%, 8% and 10% w/w.
Gelatin powder was used as standard binder for
comparison. The prepared tablets were evaluated for
weight uniformity, hardness, thickness, friability,
disintegration time and dissolution study. The
hardness of the tablet batches was within acceptable
Table 1: Physical parameters of Extracted VMSG powder
and gelatin powder. aValues are expressed as mean ± SD, n
= 3.
Properties
VMSG
Gelatin
powder a
powdera
12.76±0.39
Cold water solubity 10.35±0.55
(g/dm3)
0.556±0.04
0.510±0.05
Bulk density (g/ml)
range between 6 - 7 Kg/cm2. It is observed that the
hardness
increased
with
increasing
binder
concentration. The tablet hardness was generally
higher with the VMSG than gelatin at all
concentrations of application, an indication that
Tapped
density
(g/ml)
Hausner’s ratio
0.680±0.02
0.659±0.04
lower concentration of vigna mungo than gelatin
1.21±0.03
1.27±0.02
could be used to achieve the same level of binding.
Carr’s index (%)
13.88±0.23
15.33±0.31
The same trend was observed with the friability
Angle of repose
24.59°±1.46
27.33°±1.46
recorded for the two binders. Gelatin and VMSG
Evaluation of granules
tablets
recorded
formulation
The prepared gum granules were evaluated for
moisture content analysis and flow properties in
comparison with gelatin powder granules. The lower
bulk and tapped densities exhibited by VMSG and
gelatin granules shows that both granules were good
flowing. From the Hausner’s ratio which are almost
equal to 1.2 indicate free flowing granules. In case
Carr’s compressibility index, all granules possess better
flow properties. The angle of repose for granules was in
below 1%
(Table
4).
friability
Variations
in
in
all
weight
uniformity were less with tablets prepared using
VMSG as binder. The uniformity of weight also
indicates probable uniformity of content. The
disintegration
time
decreases
with
increasing
concentration of binder. The comparative dissolution
profiles of the paracetamol tablets prepared with
VMSG and gelatin as binder is shown in Figure 1. In
general, the amount of drug released decreased as
the binder concentration increased. (Table 4)
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Table 2. Evaluation of the granules using VMSG and gelatin as binder.
Evaluation
parameters
Binder
Angle of Repose (°)
Bulk Density (g/ml)
Tap Density (g/ml)
V1 (6%)
20.64±0.78
0.5±0.07
0.62±0.04
VMSG
V2 (8%)
26.76±1.34
0.55±0.03
0.62±0.04
V3 (10%)
21.39±1.07
0.5±0.04
0.55±0.05
G1 (6%)
27.58±0.89
0.45±0.05
0.5±0.03
Gelatin
G2 (8%)
22.86±0.43
0.53±0.03
0.58±0.06
G3 (10%)
23.94±1.51
0.48±0.06
0.55±0.03
Carr’s Index (%)
Hausner’s Ratio (%)
Moisture content (%)
19.35±0.33
1.24±0.05
3.0
11.29±0.12
1.12±0.02
3.0
9.09±0.27
1.1±0.07
4.0
10.00±0.18
1.11±0.06
2.0
8.62±0.15
1.09±0.04
4.0
12.72±0.19
1.14±0.04
4.0
a
Values are expressed as mean ± SD, n = 3.
Table 4: Evaluation of Paracetamol tablet.
Formulation
Weight
uniformity
(mg)a
605±2.37
597±3.56
603±1.85
600±1.40
603±1.91
604±3.22
Thickness
(mm) a
Hardness
(Kg/cm2) a
Formulation Code
Ingredients(mg/tab)
Paracetamol (Active)
Starch (Diluent)
VMSG
Gelatin
Aerosil
Talc
Magnesium stearate
Total weight per tablet
(mg)
V1
500
47
36
5
8
4
600
V2
500
35
48
5
8
4
600
V3
500
23
60
5
8
4
600
G1
500
47
36
5
8
4
600
G2
500
35
48
5
8
4
600
G3
500
23
60
5
8
4
600
Cumulative % drug release
6.3±0.14
4.2±0.2
0.53±0.06
6.6±0.15
4.2±O.5
0.65±0.04
6.7±0.27
4.1±0.3
0.39±0.08
6.0±0.16
4.2±0.4
0.31±0.06
6.4±0.31
4.1±0.2
0.44±0.03
6.9±0.25
4.2±0.1
0.59±0.05
a
Values are expressed as mean ± SD, n = 3.
Table 3: Formulation of tablet using VMSG and gelatin as
120
standard binder
V1
V2
V3
G1
G2
G3
DT (sec.) a
Friability
(%)a
Assay (%)a
22.2±30
27.7±20
39.6±20
26.5±40
32.0±45
45.7±30
99.7±0.79
100.2±0.53
99.9±0.81
100.7±0.72
99.20±0.48
98.5±0.33
100
V1
80
V2
V3
60
G1
G2
40
G3
20
0
0
10
20
40
60
80
100
Time (Min.)
In all binder concentrations, gelatin showed a
slow release, which progressed more slowly than the
VMSG of equal concentration. It could be said that the
gelatin and VMSG showed comparative effectiveness as
Figure 1. Cumulative percentage release of Paracetamol
tablet using VMSG as binder Vs Gelatin as standard binder.
CONCLUSION
binders to paracetamol tablets. In conclusion, VMSG
The comparative result of this study has
could compete favorably with gelatin powder as binders
concluded that VMSG may be used as a binding
in tablet formulations. (Table 4)
agent in the conventional tablet formulation. Since
VMSG displayed good binder characteristics have
greater potentialities to become the new source of
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binder and could also be exploited for the commercial
production of gums.
REFERENCES
1. Sujja A, et al. Release characteristics of diclofenac
sodium form encapsulated natural gum matrix
formulations. Int. J. Pharm. 1996, 13(9), 53‐62.
2. Panda DS, Choudhury SK, Yedukonalu SS, Guptha
R. Evaluation of gum Moringa oleifera as a tablet binder
and release retardant in tablet formulation. Ind. J. Pharm.
2008, 70(4), 614‐618.
3. Kulkarni
GT, Gowthamarajan K, Rao BG.
Evaluation of binding properties of Plantago ovata and
Trigonella foenum graceu mucilage. Ind. Drugs. 2002,
38, 422–425.
ISSN: 2229-3787
7. Mahajan R, Malhotra S. P. and Singh R.
Characterization of seed storage proteins of urdbean
(Vigna mungo). Plant Foods for Human Nutrition.
1988, 38(2), 163-173.
8. Yadav IK et al. Evaluation of seed flour of
Vigna mungo (L.) based sustained release matrix
tablets of diclofenac sodium. Journal of Pharmacy
Research, 2009, 2(5), 834-838.
9. Tsige G, Alexander S N. Evaluation of starch
obtained from Esente Ventricosum as a binder and
disintegrant for compressed tablets. J. Pharm.
Pharmacol. 1993, 45(307), 317-320.
10. Schwartz JB, Martin ET and Dehner EJ.
Intragranular starch: Compression of starch USP and
modified cornstarch. J. Pharm. Sci. 1975, 64,328332.
Preparation and evaluation of gels from gum of Moringa
olefera. Ind. J. Pharm. Sci. 2006, 68, 777‐780.
11. Liberman HA, Lachman.L, Schwartz.JB, Wadke
DA, Serajuddin ATM. Preformulation testing in
pharmaceutical dosage forms:Tablets. Marcel
Dekker: Newyork, 1989, 55.
5. Mukherjee B, Samanta A, Dinda S. Gum Odina – A
new tablet binder. Trends in Applied Sciences Research.
2006, 1(3), 309‐316.
12. Banker GS, Anderson NR, “Theory and practice
of industrial pharmacy.” 3rd edition, Varghesee
publishing house, Mumbai, 1987, 321.
6. Ibezim EC, Ofoefule SI, Omeje EO, Onyishi VI,
Odoh UE, The role of ginger starch as a binder in
acetaminophen tablets. Scientific Research and Essay.
2008, 3(2), 46-50.
13. Jaimini M, Rana AC, Tanwar YS. Formulation
4. Panda D, Si S, Swain S, Kanungo SK, Gupta R.
and evaluation of famotidine floating tablets. Curr.
Drug Del. 2007, 4, 51-55.
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