ABSTRACT
Abstract This study aimed to prepare hydrogel containing Cymbopogon citratus (DC.) Stapf, Poaceae, volatile oil encapsulated in poly (d,l-lactide-co-glycolide) nanoparticles and to evaluate its in vitro anti-herpetic activity. Polymeric nanoparticles were prepared by solvent emulsification-diffusion method and incorporated in carbomer hydrogels. In vitro release profiles for the nanogel, loaded nanoparticles and hydrogel containing free oil were evaluated by dialysis. Inhibitory activities against Herpes simplex for the formulations were investigated in Vero cells. Hydrogel was developed using nanoparticles with mean diameter of 217.1 nm and negative Zeta potential (−20.5 mV). Volatile oil release profile showed a biphasic pattern with an initial faster release and subsequent sustained phase in all formulations. Nanogel strongly inhibited virus in a non-cytotoxic concentration, 42.16 times lower than free oil, 8.76 and 2.23 times than loaded nanoparticles and hydrogel containing free oil, respectively. These results highlight the potential of nanogel to protect oil against volatilization, control release and improve its anti-herpetic activity.
ABSTRACT
Essential oils are used primarily as natural preservatives, flavourants and fragrances in cosmetic products. Several pharmacopeias possess monographs of plants which are good sources of essential oils, such as Brazilian Pharmacopeia, including Illicium verum Hook. f., Schisandraceae and Rosmarinus offi cinalis. Since determination of Hydrophile-Lipophile Balance (HLB) value of essential oils appears as a critical step for development of emulsions and other semi-solid formulations, evaluation of required HLB values for I. verum and R. offi cinalis essential oils is the aim of this study. They were obtained by hydrodistillation and several emulsions were prepared by changing emulsifiers. The couple sorbitan oleate/polysorbate 20 provided best emulsions and was used at different ratios, at a total blend concentration of 5% w/w. The lowest mean droplet diameters for R. offi cinalis and I. verum emulsions were obtained at HLB 16.5 (97.12 nm) and 16.7 (246.6 nm), respectively. Moreover, emulsions with R. offi cinalis were finer and presented some bluish reflection, characteristic of nanoemulsions. The lowest turbidity value for R. offi cinalis emulsion was also obtained at HLB 16.5 (0.33). Thus, the present study describes for the first time HLB values for R. offi cinalis (16.5) and I. verum (16.7) essential oils, contributing to their physicochemical characterization and technology development of phytopharmaceuticals.
ABSTRACT
A espécie Calceolaria chelidonioides (Scrophulariaceae), até então inédita nas citações científicas, foi estudada sob o ponto de vista farmacológico buscando-se identificar possíveis atividades antimicrobiana e antioxidante em metodologia in vitro. As partes aéreas dessa espécie demonstraram atividade antioxidante em modelo usando o radical livre DPPH. As flores de C. chelidonioides mostraram grande potencial antibacteriano frente à bactéria Staphylococcus aureus resistente a meticilina MRSA, um dos principais responsáveis em casos de infecção hospitalar.
The species Calceolaria chelidonioides (Scrophulariaceae), not scientific described so for, was studied in pharmacological aspects aiming to identify some anti-microbial and antioxidant activity. The aerial parts showed antioxidant activity using in vitro DPPH model. The flowers from C. chelidonioides showed strong antibacterial potential against meticiline resistant Staphylococcus aureus (MRSA) strains the main responsible for hospital infection complications.