AbstractIn Amazonas State (Brazil), Justicia acuminatissima (Miq.) Bremek., Acanthaceae, leaf teas are used in folk medicine to treat several inflammatory illnesses. In order to validate this medicinal application, we analyzed the acute toxicity and antioxidant, antiedematogenic and antinociceptive potentials of an aqueous extract of this species, using culture cells and animal models. The aqueous extract did not cause toxic effects on human lymphocytes in high concentration (400 μg/ml), neither on mice treated with high doses (5000 mg/kg) in an acute toxicity analysis by oral route, and also did not cause lesions in the gastric mucosa of animals treated with 300 mg/kg, which was the maximal dose used in the anti-inflammatory screening. The aqueous extract caused inhibition of inflammatory pain in formalin-induced paw licking test with all tested doses, 30, 100 and 300 mg/kg, and antiedematogenic activity at 100 and 300 mg/kg. Additionally, the aqueous extract presented statistically significant action on the release of nitric oxide by lipopolysaccharide-activated macrophages. These results and other preliminary studies support the folk use of this species, and further investigation of its action mechanism by inhibition of COX-2 or related metabolite would be interesting.

Justicia acuminatissima (Miq.) Bremek., Acanthaceae, is a subshrub found in northern Brazil, where it is widely used by the population of this region as an anti-inflammatory medicine. Despite this popular use, there is no pharmacognostical data to support the correct identification of this species. We therefore performed a morpho-anatomical, histochemical and phytochemical analysis of the leaves of this species, using well-known methods. The leaves are simple, exstipulate, green on the surfaces, and pubescent, with a lanceolate shape, crenate margin, pinnate venation and decussate phyllotaxy. The parenchyma is palisade and spongy, and its vascular system is bilateral. Glandular and non-glandular trichome and cystoliths were also detected. There are diacytic stomata on both the adaxial and abaxial surfaces of epidermis. Histochemical tests revealed the presence of phenolic compounds, amide and protein. Phytochemical tests showed the presence of coumarins, tannins, catechins, saponins and steroids.

The aim of the present work is to characterize the vegetal raw material of the Calycophyllum spruceanum (Benth.) Hook. f. ex K. Schum., Rubiaceae, known as "mulateiro", and to evaluate the influence of extractive parameters for attainment of standardized aqueous extractive solutions. The physical-chemical characterization of the samples was performed using pharmacopoeic and not pharmacopoeic methodologies. A 2³ factorial design was used to evaluate the influence of extraction techniques (infusion/decoction), drug: solvent ratio (2.5 and 7.5%), and extraction time (5 and 15 min) on the total tannin content of aqueous extractive solutions from C. spruceanum. The extractive solution that showed higher total tannin and dry residue content had their physical-chemical characteristics determined. The results suggest that an aqueous extractive solution from rinds of C. spruceanum barks with higher tanning yield (9.9 g%), must be standardized using decoction as extraction methodology, with 2.5% of vegetal drug for an extraction time of 15 min. The results of the physical-chemical characterization suggest that environmental factors modify the properties of this species and, therefore, they can influence the quality and security of a product derived from this medicinal plant.