ABSTRACT
Abstract Aedes aegypti (Diptera: Culicidae) is the main vector of some neglected diseases, including dengue. It is very important to develop formulations that increase effectiveness of vector control with low toxicity. Quercetin is a plant-derived flavonoid that modulates the development of some insects. The low water solubility of quercetin impairs the development of water-dispersible commercial products. To circumvent this problem, the preparation of nanoformulations is considered promising. Thus, this study aimed to evaluate the effect of bulk and quercetin nanosuspension against A. aegypti larvae and also to investigate their ecotoxicity. Quercetin nanosuspension was produced by a solvent displacement method followed by solvent evaporation and was maintained in two different temperatures (4 and 25 ºC). Its size distribution and zeta potential were monitored along 30 days. The influence of quercetin nanosuspension and bulk-quercetin was investigated at various concentrations against A. aegypti and the green algae Chlorella vulgaris. The quercetin nanosuspension presented higher stability at 4 ºC and negative zeta potential values. Quercetin nanosuspension and bulk-quercetin adversely affected the larvae development, especially at the highest concentrations. Larvae mortality was between 44% and 100% (48 h) for quercetin nanosuspension at 100 and 500 ppm, respectively. The bulk-quercetin induced around 50% mortality regardless the concentration used at this same time-period. Absence of emerging mosquitoes from water was observed on the survival larvae of all the treated groups. Quercetin nanosuspension was less toxic than bulk-quercetin against C. vulgaris, especially at higher concentrations. These data indicate that quercetin nanosuspension may represent a potential larvicide for A. aegypti control, once they induced larvae death and inhibited the survival ones to emerge from water. In addition, it did not demonstrated ecotoxicity against a non-target organism, highlighting its better properties, when compared to the bulk-quercetin.
ABSTRACT
ABSTRACT Diabetes mellitus is a chronic and severe metabolic dysfunction, it's slow and progressive evolution interferes directly in the metabolism of carbohydrates, fats and proteins, causing hyperglycemia, glycosuria, polydipsia, hyperlipidaemia, among others. The aim of this study was to evaluate the antidiabetic effect of hydroethanolic extract and granulated of Calophyllum brasiliense Cambess., Clusiaceae, species in diabetic rats as well as it's biochemical parameters. The results demonstrated that both the pharmaceutical forms, hydroethanolic extract and granulated, were able to reduce significantly (p < 0.001) hyperglycemia and glycosuria, in addition to improve polydipsia, polyuria, and weight loss. Treatments using hydroethanolic extract and granulated were also able to reduce significantly levels of triacylglycerides, cholesterol and low-density lipoprotein, as well as the transaminases, urea and creatinine levels. Therefore, it is concluded that these pharmaceutical forms have anti-diabetic effect and act improving the biochemical parameters, this effect is probably due to the high content of polyphenolic compounds found in the formulations.
ABSTRACT
Copaiba trees and their oleoresin is an important natural product used as an anti-inflammatory and antimicrobial drug, in particular for gynecological infections. The in vitro release profile of sesquiterpenes in a vaginal cream containing copaiba (CVC – copaiba vaginal cream) oleoresin in buffered solutions at different pHs was evaluated in the present study. The dissolution test revealed that trans-caryophyllene (TC) was constantly released until the final test time. The maximum peaks were found at a concentration of 478.79 nL/mL for the buffer at pH 5 and at a concentration of 475.99 nL/mL for the buffer at pH 6, with a percentage release of 50.52% and 50.21%, respectively. Likewise, the caryophyllene oxide (CO) was released into the buffers at pHs 5 and 6, with maximum release peaks at 60 minutes at a percentage of 31.8% and 33.5% corresponding to concentrations of 2.779 and 2.925 μg/mL, respectively. The release and dissolution profiles of the sesquiterpene compounds indicated that a pH of 5-6 in the dissolution media is adequate for release of these markers of antimicrobial activity in Copaifera duckei Dwyer. Therefore, these conditions possibly favor the therapeutic action of CVC.