Compression behavior of formulations from Phyllanthus niruri spray dried extract.

The aim of this study was to evaluate the compression behavior of Phyllanthus niruri spray dried extract as well as the influence of excipients on the properties of tablets containing a high dose (70% by weight) of this product. The effect of excipients was studied by a 22 factorial design. The factors investigated were the type of disintegrant (croscarmellose sodium and sodium starch glycolate) and the type of filler/binder (microcrystalline cellulose and dibasic dicalcium phosphate). The tablets were produced on a single punch tablet press using a constant compression force of 5000 N. The tablets formulated with microcrystalline cellulose presented a plastic behavior while the tablets containing dibasic dicalcium phosphate disclosed a fragmentary behavior. The disintegration time was significantly influenced by both factors, however, the tensile strength was only affected by the filler/binder. Additional experiments considering the influence of the compression force (2500 N and 5000 N) and the proportion of croscarmellose sodium (1.5%, 3.0% and 6.0%) on the mechanical properties of the tablets were performed by a 2 x 3 factorial design. Both factors significantly affected the tensile strength, friability and disintegration time of the tablets.

Validation of a LC method for the analysis of phenolic compounds from aqueous extract of Phyllanthus niruri aerial parts.

A reversed-phase high-performance liquid chromatographic separation and quantitative method using a phosphoric acid-acetonitrile gradient was developed to analyze phenolic compounds present in aqueous extract from the aerial parts of Phyllanthus niruri. The chromatographic method was validated for linearity, precision and accuracy for both reference substance (gallic acid) and for three well resolved peaks from P. niruri aqueous extract. Both calibration curves were linear with correlation coefficients higher than 0.999. The reproducibility for the three peaks ranged from 2.3% to 4.6% and the accuracy for gallic acid in the aqueous extract was 103%. The method allowed the complete resolution of three peaks, one of them was identified by diode array detection as gallic acid. The analysis of the botanic morphological elements of the aerial parts from P. niruri showed that the leaves have a higher amount of phenolic compounds than the branches.

Influence of adjuvants on the dissolution profile of tablets containing high doses of spray-dried extract of Maytenus ilicifolia.

A 2(3) factorial design was used in order to evaluate the influence of some adjuvants on the dissolution profile of tablets containing high doses of Maytenus ilicifolia spray-dried extract. Tablets were prepared on a single punch tablet press using 15 mm flat punches by individual direct compression of 650 mg from each formulation containing 375 mg of the spray-dried extract. The factors investigated were disintegrant (croscarmellose sodium or sodium starch glycolate), lubricant (colloidal silicon dioxide or magnesium stearate) and filler/binder (microcrystalline cellulose or lactose). The dissolution profiles were analyzed to determine the dissolution kinetics, the dissolution half-lives (t50%), the similarity factor (f2) and the dissolution efficiency (DE %), which was selected as the response criteria to evaluate the factorial design. The results revealed that in spite of the high content of spray-dried powder in the tablets, the dissolution profiles of the extract did depend on the adjuvant used. The filler/binder had the most important effect on the dissolution efficiency of the tablets.