Formulation development of chewable tablets containing Phyllanthus emblica Linn. fruit extract by direct compression

Indian gooseberry (Phyllanthus emblica Linn.), a plant in family Euphobiaceae, is a tree growing in tropical parts of Southeast Asia. Its fruits have been widely used in folk medicine. The uses of this plant are associated with various pharmacological activities such as antioxidant, hepatoprotective, cholesterol-lowering, anti-inflammatory, analgesic, antipyretic and antitussive. The purposes of this study were to develop chewable tablets containing Phyllanthus emblica Linn. spray dried fruit extract and to evaluate physicochemical properties of the products and their stability. The chewable tablets were prepared by direct compression using a single punch tableting machine. In some cases, spray dried extract was coated with ethylcellulose before incorporating into the formulations. The effects of binders, lubricants and flavoring agents on the tablet properties, such as appearance, hardness, total tannins and gallic acid contents, as well as the release of total tannins were investigated. The stability studies of the chewable tablets were carried out under refrigeration, at ambient temperature and 75%RH or uncontrolled humidity, also at 40 °C and 75%RH for 3 months. Consumer acceptance of tablet appearance, flavor and mouth feel was tested for selected formulations. The microbial limit test was carried out for the spray dried extract before tablet preparation, and for the products prior to the consumer acceptance test. The results showed that the chewable tablets containing 30% spray dried Phyllanthus emblica Linn. fruit extract could be prepared by direct compression. The process required sufficient lubrication. Under storage condition at 40 C and 75%RH, the color of the tablets was changed to brownish. The hardness of tablets, however, behaved variably for the formulations containing uncoated or coated extract. It was significantly increased when the tablets contained uncoated extract, while decreased when the tablets contained coated extract (p < 0.05). The total tannins and gallic acid contents were more stable when the chewable tablets were prepared with microcrystalline cellulose PH 102 and stored at ambient temperature. The release of total tannins content from the tablets cut into pieces was dependent on the type of binder used. With copovidone, the release was retarded. The formulation which was relatively stable and accepted by volunteers contained 30% Phyllanthus emblica Linn. spray dried fruit extract, 20.35% mannitol, 20.35% xylitol, 10% microcrystalline cellulose PH 102, 10% talc, 5% citric acid, 1% aspartame, 2% sodium chloride, 1% magnesium stearate and 0.3% silicon dioxide.