Seasonal variation in the production of secondary metabolites and antimicrobial activity of two plant species used in Brazilian traditional medicine

Guapira graciliflora and Pseudobombax marginatum are two species used in the treatment of various diseases in traditional medicine of the Brazilian semiarid region, but no studies assessing their phytochemical and pharmacological properties have been reported. This study aimed to evaluate seasonal variation in the production of secondary metabolites and antimicrobial activity of these plants. The broth microdilution test was used against pathogenic microorganisms to evaluate the antimicrobial activity. The content of total polyphenols and flavonoids was determined by ultra violet (UV) spectrophotometry using gallic acid and quercetin as standards respectively. The concentration of polyphenols was higher in winter for P. marginatum and in summer for G. graciliflora, while for flavonoids the opposite occurred. Regarding the antimicrobial activity, only P. marginatum showed inhibition against seven tested strains and antibiosis against four, with variation in the minimum inhibitory concentration (MIC) and minimum microbicide concentration (MMC) between the two seasons. G. graciliflora showed no activity. The results show that the chemical composition of the extracts from P. marginatum and G. gracilliflora exhibits seasonal variation, with the first plant showing moderate antimicrobial activity.Keywords: Seasonal variation, phenolic compounds, medicinal plants, Gapira graciliflora, Pseudobombax marginatumAfrican Journal of Biotechnology Vol. 12(8), pp. 847-85

Schinopsis brasiliensis engl. to combat the biofilm-dependents diseases in vitro

Dental caries and periodontal disease are the most prevalent of the biofilm-dependent diseases. With numerous side effects on the use of chlorhexidine, the search for new safe therapeutic alternatives for microorganisms involved with these diseases increases every day. This study aimed to evaluate the antimicrobial activity and cytotoxicity of extracts made from the bark of Schinopsis brasiliensis Engl. against five oral microorganisms and analyze their phytochemical and thermal degradation profile. The liquid-liquid partition was performed with hexane, chloroform and ethyl acetate. The identification and quantification of the chemical marker was done. Antimicrobial activity was evaluated based on the minimum inhibitory concentration. The cytotoxicity was analyzed based on the hemolysing potential of the samples. The thermal degradation profile was performed by two different methods. Gallic acid was identified as the main compound of the samples and showed the highest amount in the chloroform fraction. All samples were able to inhibit the growth of the microorganisms tested and showed no cytotoxicity. The ethanol extract absorbs less heat than the fractions. All samples exhibited exothermic peak consistent with degradation of gallic acid. Based on the results, the samples used are potential candidates for use in dental formulations for biofilm control924CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQSem informaçã

Dissolution and uniformity of content of tablets developed with extract of <i>Ximenia americana L</i>.

<div><p>Herbal medicines currently represent an important part of the world pharmaceutical market, which shows growing interest in the use of herbal medicines. However, the production of such medicines involves a complex series of steps, which determine the production viability and the quality of the final product. <i>Ximenia americana</i> L. is a plant occurring in several regions of the world, with well-known and applied medicinal properties. Thus, the aim of this work was to develop and evaluate the physical and physical-chemical quality of tablets produced with <i>X</i>. <i>americana</i> L. extract. The extract was spray-dried from a hydroethanolic extractive solution and characterized as to its phytochemical composition. The chemical marker was determined and quantified using validated chromatographic methods. These methods indicated the presence of gallic acid at a concentration of 1.61 mg g^-1. Formulations were proposed and analyzed for their flow and compaction properties. The best formulation was used to obtain a batch of tablets, which was evaluated for its quality characteristics and showed to be within the pharmacopoeial specifications for average weight, hardness, friability, and disintegration time. The dissolution profile of the tablets produced was obtained, showing the release of about 70% of the vegetable extract content within 30 minutes. Results showed that it was possible to obtain herbal tablets containing a high content of vegetal extract by direct compression, developing a rapid process of formulation and production and guaranteeing the quality characteristics of the final product.</p></div

Variation coefficients regarding the robustness evaluation of the dissolution test.

<p>Variation coefficients regarding the robustness evaluation of the dissolution test.</p

Validation parameters for the spectrophotometric quantification method of the extract in tablet.

<p>Validation parameters for the spectrophotometric quantification method of the extract in tablet.</p

Percentual component concentration of the formulations proposed for the tablet.

<p>Percentual component concentration of the formulations proposed for the tablet.</p

Validation parameters for the chromatographic quantification method of the <i>X</i>. <i>americana</i> extract.

<p>Validation parameters for the chromatographic quantification method of the <i>X</i>. <i>americana</i> extract.</p

Average dissolution profile of the tablets with minimum and maximum variations.

<p>Average dissolution profile of the tablets with minimum and maximum variations.</p

Data from the average weight determination.

<p>Data from the average weight determination.</p

Linearity analysis: (A) Calibration curve chromatograms; (B) Calibration curve data.

<p>Linearity analysis: (A) Calibration curve chromatograms; (B) Calibration curve data.</p