Abstract:
Purpose: Cashew tree Anacardium occidentale is a spreading ever green perennial tree. The plant
is naturalized and cultivated in the warmer parts of Sri Lanka. This study focused on evaluating
purified cashew gum as an effective binding agent in tablet formulation using a range of binder
solution strengths and different tablet formulations. A difficult to formulate “all starches filler
tablet” was attempted as a challenge for the binding strength of the purified cashew gum. Method:
Crude cashew gum was collected from the main trunk and purified by dialysis. The aqueous
solution containing higher molecular mass fraction obtained from dialysis was then lyophilized.
Placebo, pyridoxine hydrochloride 2 mg and carbamazepine 100 mg tablets were prepared using
the high molecular mass fraction known as purified cashew gum. The physico-chemical properties
of the purified gum were investigated. Physical properties of the tablets prepared with four binders,
purified cashew gum, gum xanthan, hydroxypropyl methylcellulose and maize starch were studied
and compared with respect to diameter, thickness, hardness, friability, weight variation and
disintegration time. Results: The purified cashew gum was of a light amber color, glistening pieces
and was odorless. It was found that the gum resembles the properties of gum acacia with
parameters well within those of British Pharmacopeia specifications. A unique all starches filler
tablets were a success. Tablets prepared with all four binders exhibited similar physical properties.
Conclusion: It was possible to purify the gum to a specified quality similar to that of gum acacia.
Tablets made with the cashew gum met the tested British Pharmacopeia specifications similar to
the conventional binders indicating the potential for the use of purified cashew gum as a
pharmaceutical binding agent.