Evaluation of Seed Mucilage of Hibiscus Sabdariffa Linn as Tablet Binder

 

Ch. Anupama1*, P. Padmakumari1, K. Abbulu1, Arti Mohan1 and A. Ppratyusha2

1Malla Reddy Institute of Pharmaceutical Sciences, Andhra Pradesh, India

2CMR College of Pharmacy, Andhra Pradesh, India

 

 

ABSTRACT:

The aim of present study is to evaluate the mucilage of Hibiscus sabdariffa seeds as tablet binder using Diclofenac sodium as standard drug .To the best of our knowledge no significant work has been reported on seed mucilage as tablet binder. Physicochemical characteristics of mucilage were studied which confirmed the mucilage nature. The tablets were prepared by wet granulation technique using mucilage as tablet binder. The prepared tablets were evaluated for their granulating and binding properties. The tablets exhibited good uniformity and drug release was more than 85% in 90 min. Tablet’s hardness and disintegration time was increased with increasing binder concentration and friability values were decreased with increase in binder concentration. All these confirm the use of Hibiscus sabdariffa as binder in tablet formulation.

 

KEYWORDS: Hibiscus sabdariffa, mucilage, binder.

 

INTRODUCTION:

Binders are the 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 flowing quality1. Mucilage are most commonly used adjuvant in pharmaceutical preparations. They possess a variety of pharmaceutical properties, which include binding, disintegrating, suspending, emulsifying and sustaining properties2. Natural mucilage are preferred over semi-synthetic and synthetic materials due to their non-toxic, low cost, free availability, emollient and non-irritating nature3.

 

The present study deals with the isolation of the gum from the seeds of Hibiscus sabdariffa and its application as binding agent in tablet formulation.  Hibiscus sabdariffa, a shrub belonging to the family Malvaceae. Commonly referred as yerra gogu (telugu), species is found amply in all areas of India. The binding properties of this gum were compared with starch which was used as a standard binder at 10% concentration.

 

MATERIALS AND METHODS:

The seeds of Hibiscus sabdariffa Linn were obtained from Krishna District; A.P. Diclofenac sodium was obtained from Reddy Laboratories as a gifted sample, lactose obtained from Shreeji Chem, Mumbai. All other materials used in this study were of analytical grade.

 

ISOLATION OF MUCILAGE4,5,6:

The seeds of Hibiscus sabdariffa were soaked in distilled water for 12 hours, boiled for half an hour and kept aside for one hour to release mucilage into water.


The material was squeezed in a muslin bag to remove the marc from the filtrate. Then, equal volume of acetone was added to filtrate to precipitate the mucilage. The mucilage was separated, dried in an oven at temperature less than 500c, powdered and passed through sieve no.80. The powder was stored in desiccator until further use.

 

PHYSICOCHEMICAL PROPERTIES OF GUM:

The physic-chemical properties such as solubility, swelling index, loss on drying, viscosity and PH were determined according to Indian pharmacopoeial procedure7, using air dried powder of gum. The PH of mucilage was determined using a digital pH meter. The viscosity of gum solution was determined at 250c using Ostwald’s viscometer after 24 hours of hydration. Results  shown in Table:1

 

TABLE:1     PHYSICO CHEMICAL PROPERTIES OF Hibiscus sabdariffa SEED MUCILAGE

Parameter

Hibiscus  sabdariffa

Test for mucilage: Ruthenium Red

positive

solubility

Soluble in cold water and hot water forming colloidal solution

Swelling Index

33

PH

5.8

Loss on drying % w/w

8.2

Viscosity

20 – 100 cps

 

PREPARATION AND EVALUATION OF GRANULES:

All the materials were passed through a mesh sieve with aperture of 250 µm before use. The tablets were prepared by wet granulation method. The compositions of tablets is given in Table: 2

 

Diclofenac sodium and lactose were thoroughly mixed and the solution of the mucilage of specified concentration was prepared by dispersing the mucilage in water. The mucilage solutions were used for moistening the powder mixture, for preparing tablets to evaluate the binding potential. The wet mass was then passed through sieve no.16 and dried at temperature not exceeding 500c in a hot air oven for 30 minutes. The dried granules were again passed through a sieve no.20. The same method was followed in the preparation of standard formulation (STD) using starch mucilage 10%w/w.

 

 

The flow properties of the granules were evaluated by angle of repose, Compressibility Index and Hausner’s Ratio. Results were shown in Table: 3

 

The bulk density8 was calculated by weighing 20gm of granules were introduced into a 100ml measuring graduated cylinder. The cylinder was fixed on the bulk density apparatus and the timer knob was set for 100 tapings. Then noted the volume continued another 50 tapings and noted the final volume. This volume was noted as bulk volume. Based on the bulk and tap densities both the Carr’s Index (%) [(Tapped density-bulk density) X 100/tapped density] and Hausner Ratio (tapped density/bulk density) were calculated.

 

Angle of repose was determined by fixed funnel method. Funnel with the end of the stem cut perpendicular to the axis of symmetry was secured with its tip at a given height (H) above a graph paper placed on a flat horizontal surface. The material was carefully poured through the funnel until at apex of the conical pile so formed just touches the tip of the funnel. The mean diameter (2R) of the base of the powder cone was determined and the tangent of the angle of repose is given by tan α = H/R, where α is the angle of repose. All the results were compared with the standard formulation (STD).

 

PREPARATION AND EVALUTION OF TABLETS:

The granules were lubricated with 1% w/w magnesium stearate and talc. The tablets were compressed by using Cadmach single punch machine using 6mm round flat faced punches. The tablets of average weights 250mg were prepared. Four batches of tablets were prepared by using isolated mucilage of four different concentrations (2%, 4%, 6% and 8%) were used, starch mucilage (10% concentration) was used as a standard binder for comparison.

 

The prepared tablets were evaluated for weight variation, hardness, friability, disintegration time and dissolution. Disintegration time was determined using USP tablet disintegration apparatus (model ED-2 Electrolab, Mumbai) using water (900 ml) as medium at 37±0.5˚C. Weight variation test was carried out as per IP. Monsanto hardness tester and the Roche friabilator were used to test hardness and friability respectively as per IP. In vitro dissolution studies were carried out using PH 7.2 phosphate buffer as a dissolution medium. Results were shown in Table: 4 and 5.


 

 

TABLE:2 COMPOSITION OF TABLETS CONTAINING Hibiscus sabdariffa SEED MUCILAGE AS BINDER

S. No

Ingredients

F1

F2

F3

F4

STD

1

Diclofenac sodium

50mg

50mg

50mg

50mg

50mg

2

H.sabdariffa mucilage

2 %

4%

6%

8%

 

3

Starch mucilage

-

-

-

-

10%

4

Talc

1%

1%

1%

1%

1%

5

Mg stearate

1%

1%

1%

1%

1%

6

Lactose

q.s

q.s

q.s

q.s

q.s

7

Total weight

250 mg

250 mg

250 mg

250 mg

250 mg

TABLE:3     EVALUATION OF GRANULES

Properties

F1

F2

F3

F4

STD

Tapped bulk density

0.635

0.632

0.636

0.655

0.634

Loose bulk density

0.572

0.575

0.571

0.550

0.570

Carr’s Index

9.206

9.018

10.22

10.56

10.14

Hausner’s ratio

1.10

1.09

1.11

1.10

1.11

Angle of repose

23093'

24025'

24073'

24035'

22095'

 

TABLE:4     EVALUATION OF TABLETS

Formulation

Hardness

Friability%

Wt variation%

Disintigration time

F1

2.5±0.16

0.5168±0.01

249.25±2.01

2 min 20 sec

F2

3.0±0.13

0.4532±0.03

248.75±2.39

3 min 13sec

F3

4.0±0.17

0.3125±0.02

247.35±2.35

3 min 65sec

F4

5.2±0.13

0.2456±0.03

250.45±2.75

4 min 50sec

STD

5.6±0.14

0.2105±0.02

248.65±2.16

4 min 14sec

 

 

TABLE:5    IN VITRO DISSOLUTION PROFILE :

Time(min)

PERCENTAGE OF DRUG RELEASE

F1(2%)

F2(4%)

F3(6%)

F4(8%)

STD

0

0

0

0

0

0

10

36.23

34.21

29.21

26.34

40.23

20

46.37

43.58

36.21

35.24

56.34

30

60.21

59.21

48.84

44.34

68.39

40

74.29

63.35

60.21

58.21

79.21

50

80.21

79.21

78.24

74.31

83.34

60

93.21

90.32

89.45

88.23

96.36

90

93.56

92.32

90.32

89.24

97.89

120

94.13

93.21

92.21

90.32

98.34

 

 

 


RESULTS AND DISCUSSION:

Mucilage obtained from Hibiscus sabdariffa seeds was in an amorphous free flowing powder with brown colour. Mucilage nature was confirmed by various physicochemical properties. The granules were prepared and evaluated for tapped bulk density, loose bulk density, Carrs index, Hausner’s ratio and angle of repose. Flow property of granules was determined by angle of repose and it was found that the values are in the range of 22˚ 95' - 24˚ 25'. All the formulations tested for a Carr’s index ranging from 9-10%, Hausner’s ratio was below 1.12. Hence all granules exhibited good flow property.

 

Four batches of tablets were prepared using four different concentrations of mucilage and starch mucilage as standard (10% concentration). The prepared tablets were evaluated for weight variation, hardness, friability, disintegration time and in vitro dissolution profile.

 

All batches exhibited good uniformity, tablet hardness and disintegration time was increased with increasing binder concentration, the friability values were decreased with increase in binder concentration. In vitro dissolution study showed that drug release from the tablets prepared by mucilage at four different concentrations was more than 85% in 90 minutes.

 

 

CONCLUSION:

The evaluation of tablets reveals that the binding efficacy of tablets prepared using Hibiscus sabdariffa seed mucilage is comparable with the tablets prepared using 10%w/w starch as a standard binder. Therefore, it is concluded that Hibiscus sabdariffa seed mucilage could be used well as a binding agent in the formulation of tablet dosage forms.

 

REFERENCES:

1.        King R.E., Tablets in Remington’s Pharmaceutical Sciences, 15th Ed, Mack pub. Coy. Easton, pennsylvaniya, 1975:1587.

2.        Shirsand S.B et al. Plantago ovate mucilage in the design of fast disintegrating tablets. Indian J. Pharm. Sci.. 2009;12: 41-45.

3.        Washi SP et al. Plantago ovate; genetic diversity, cultivation, utilization and Chemistry, Indian J Nat Prod.1985; 1: 3-6.

4.        Kulkarni. G.T et al. Evaluation of binding properties of Plantago ovata and Trigonella foenum graecum mucilages. Indian drugs.2002; 39(8): 422-425.

5.        Sharma. S et al. Fast dissolving tablets of promethazine theoclate by using natural super disintegrants. Research. Pharm and Tech..2008;1(3): 218-224.

6.        Girish k jain,et al .Gums and mucilages versatile excipients for pharmaceutical formulations. Asian journal of pharmaceutical sciences. 2009;4(5):309-323

7.        The Indian Pharmacopoeia, Vol.II, Govt.of India, Ministry of Health and Family    Welfare, The controller of Publication, New Delhi,1996.

8.        CVS Subramanyam, Text book of Physical pharmaceutics, Vaiiabh prakashan, Delhi 2007.

 

 

Received on 16.09.2010

Accepted on 12.10.2010                                                    

© A&V Publication all right reserved

Research Journal of Pharmaceutical Dosage Forms and Technology. 2(6): Nov.-Dec. 2010, 370-373