Influence of the capuchin hydroethanolic extract (Tropaeolum majus L. ) on the stability of ketoconazole

The stability of pharmaceuticals is influenced by several factors, directly related to the product, or to environmental factors, such as the presence of light and oxygen. Ketoconazole is an antifungal drug of the azole class that is prone to degradation processes, such as oxidation and hydrolysis, changing from white to pink, suggesting the formation of degradation products. Capuchin (Tropaeolum majus L.) is a species of pharmacological interest due to its phytochemical composition; it is rich in vitamin C and flavonoids with known antioxidant activity. The objective of this work was to investigate the antioxidant activity of capuchin hydroethanolic extracts and evaluate their influence on the stability of ketoconazole. For the evaluation of the antioxidant activity of the extracts, the DPPH radical was used. Different ketoconazole gel formulations were manipulated and subjected to a stability study to compare the antioxidant efficiency of the extract and sodium metabisulphite by analyzing the samples by ultraviolet scanning. Microbiological assays were performed to evaluate the activity of ketoconazole against the fungus Candida albicans. The extract solution presented antioxidant activity equivalent to a 12.71 µg/mL metabisulfite solution, and a 0.085 µg metabisulfite/µg extract ratio was calculated. In the spectrophotometric analysis, it was observed that the absorption spectrum of the extract-containing formulation presented differently from the others, with a possible advantage in relation to the synthetic antioxidant. In the microbiological analysis, only the samples that remained at room temperature formed an inhibition halo. Thus, the potential of a natural active was evaluated, representing a possible alternative for application in pharmaceutical formulations.

Evaluating the discriminatory power of a dissolution assay for rosuvastatin calcium capsules: Solid-state properties and dissolution media

We propose to evaluate the dissolution properties of rosuvastatin calcium (ROSC) capsules in different media to characterize the discriminatory power of the assay method. Dissolution assays were performed in media with different pH, and including the surfactant sodium dodecyl sulfate (SDS). Several immediate-release formulations were manufactured using the commercial raw material characterized as amorphous solid. The hydrophobic adjutant magnesium stearate was employed in some formulations due to its negative effect in the wettability and dissolution efficacy of solid dosages. These formulations showed the lower dissolution efficacy values in media without surfactant; however, when SDS was added to the medium, the dissolution efficacy increased, and the discriminatory power was lost. In spite of micellar solubilization does not increase the ROSC solubility, it modifies the discriminatory power of the assay method, increasing the wettability of the powder mixtures. The crystalline form M of ROSC was recrystallized in our laboratory, and it showed lower solubility in water than amorphous solid. However, its dissolution properties were not influenced by SDS. These results are important to develop dissolution assays for other hydrophilic drugs with increased water solubility, once that dissolution media with surfactants increase the wettability of the formulations, leading to an overrated dissolution rate.

Multirresistência microbiana e opções terapêuticas disponíveis / Microbial multi-resistance and available therapeutic options

JUSTIFICATIVA E OBJETIVOS: Devido ao uso irracional de antimicrobianos e a administração empírica, vários problemas de resistência microbiana surgiram como um novo desafio para a terapêutica, causando elevados índices de mortalidade. Dentre os grupos de micro-organismos relacionados a infecções resistentes destacam-se: Staphylococcus aureus resistente à meticilina e Staphylococcus aureus resistente à vancomicina, Enterococcus sp resistentes a diferentes classes de antimicrobianos, Streptococcus pneumoniae resistente à penicilina, Klebsiella pneumoniae carbapenemase, Pseudomonas aeruginosa e Acinetobacter baumanii resistentes aos carbapenêmicos e ainda as enterobactérias produtoras beta-lactamases de espectro ampliado (ESBL). O objetivo deste estudo foi rever na literatura científica a abordagem do surgimento de micro-organismos multirresistentes e as opções terapêuticas disponíveis no Brasil. CONTEÚDO: Novos antimicrobianos são lançados no mercado com o intuito de alcançar tratamento efetivo para infecções causadas por micro-organismos resistentes. Para abordar os mecanismos de resistência mais comuns, das novas opções terapêuticas disponíveis no Brasil e das novas diretrizes de uso desses fármacos. CONCLUSÃO: Enquanto o uso dos medicamentos antimicrobianos continuarem sendo de modo irresponsável e não for cumpridaa legislação para seu uso, os novos fármacos serão eficazes apenas temporariamente, fazendo constante o problema da multirresistência microbiana.

BACKGROUND AND OBJECTIVES: Due to antibiotics irrational use and the empiric administration, many microbial resistance problems become a new therapeutic challenge, causing elevated mortality rates. Among the microorganisms groups related with resistant infections are: methicillin-resistant and vancomycin-resistant Staphylococcus aureus, multi-resistant Enterococcussp, penicillin-resistant Streptococcus pneumoniae, Klebsiella pneumoniae carbapenemase, carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter baumanii and extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL). The aim of this work was carry out a review of scientific literature in order to discuss the emergence of multidrug-resistant microorganism sand the therapeutic options available in Brazil. CONTENTS: New antimicrobials are launched in order to achieve effective treatment for resistant microorganisms infections. To discuss the most common resistance mechanisms, new therapeutic options available in Brazil and new guidelines for the use of these drugs. CONCLUSION: While the use of antimicrobial drugs to keep so irresponsible and the law for its use not met, the new drugs will be effective only temporarily, keeping constant the microbial multi-resistance problem.