CNS activities of liquid and spray-dried extracts from Lippia alba-Verbenaceae (Brazilian false melissa).

The CNS activity of Lippia alba liquid and spray-dried extracts, containing the non-volatile fraction from the leaves, was investigated. L. alba liquid extracts were prepared by percolation with EtOH 40, 60 or 80%. The liquid extracts, named ES(40%,) ES(60%) and ES(80%,) were concentrated, the ethanol eliminated and then tested in Swiss mice to evaluate its sedative and anticonvulsant effects. The animals received the extracts, orally, in doses corresponding to 200 mg of dry residue by kilogram of body weight. All mice were evaluated in the barbiturate-induced sleep test. Similarly, other groups of mice were submitted to convulsions induced by pentylenetetrazol (PTZ). The concentrated extract obtained from ES(80%) showed the most significant sedative and myorelaxant effects as well as the highest total flavonoid content (66 mg/100 g, expressed in apigenin). Two spray-dried powders, SDP(1) and SDP(2), were prepared from ES(80%) using as excipients, respectively, colloidal silicon dioxide (CSD) and CSD associated to beta-cyclodextrin. Only SDP(1) showed sedative profile similar to that presented by ES(80). In conclusion, we demonstrated that the non-volatile fraction of L. alba, extracted in ethanol 80% (v/v), presents sedative and myorelaxant effects and that, among the tested extracts, this presents the highest flavonoid content. We demonstrated also the technological feasibility of spray-dried extracts and the influence of the excipient on its sedative properties.

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.

Ichthyotoxic activities of Ateleia glazioviana Baill. and Thinouia coriacea Britt.

Ethanolic extracts from leaves and roots of Ateleia glazioviana (Leguminosae-Papilionoideae) and the saponin containing fraction from Thinouia coriacea (Sapindaceae) have been studied for ichthyotoxic activity on Phallocerus caudimaculatus and Geophagus brasiliensis. The ethanolic extracts were used in doses ranging from 50 to 100 ppm, based on the dry residue. The saponin fraction was used at doses of 1-10 ppm. The two plant extracts and saponin fractions were found to be ichthyotoxic, justifying their traditional role as an aid in fishing.