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Zanthoxylum tinguassuiba essential oil (ZtEO) contains α-bisabolol, a known antiglioma sesquiterpene, among other potentially active substances. Medical applications of this essential oil require advances in the design of distinctive carriers due to its low water solubility and easy degradation by heat, light, and oxygen. The aim of this work was to evaluate enhancement in oxidative stability and the ability to reduce glioblastoma cell viability of ZtEO loaded into liposomes. Multi- and unilamellar vesicles were prepared to carry ZtEO. By using thermal analysis, it was observed that thermal-oxidative stability of the liposomal ZtEO was enhanced, when compared to its free form. Liposomal ZtEO also presented significant apoptotic-inducing activity for glioma cells. These results show that liposomal systems carrying ZtEO may be a potential alternative for gliobastoma treatment.

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A reversed-phase high performance liquid chromatography method has been developed and validated for determination and quantitation of the natural sesquiterpene (-)-alpha-bisabolol. Furthermore the application of the method was done by characterization of chitosan milispheres and liposomes entrapping Zanthoxylum tingoassuiba essential oil, which contains appreciable amount of (-)-alpha-bisabolol. A reversed-phase C(18) column and gradient elution was used with the mobile phase composed of (A) acetonitrile-water-phosphoric acid (19:80:1) and (B) acetonitrile. The eluent was pumped at a flow rate of 0.8 mL/min with UV detection at 200 nm. In the range 0.02-0.64 mg/mL the assay showed good linearity (R(2 )= 0.9999) and specificity for successful identification and quantitation of (-)-alpha-bisabolol in the essential oil without interfering peaks. The method also showed good reproducibility, demonstrating inter-day and intra-day precision based on relative standard deviation values (up to 3.03%), accuracy (mean recovery of 100.69% +/- 1.05%) and low values of detection and quantitation limits (0.0005 and 0.0016 mg/mL, respectively). The method was also robust for showing a recovery of 98.81% under a change of solvent in standard solutions. The suitability of the method was demonstrated by the successful determination of association efficiency of the (-)-alpha-bisabolol in chitosan milispheres and liposomes.

The interest of the pharmaceutical industry in lipid drug delivery systems due to their prolonged release profile, biocompatibility, reduction of side effects, and so on is already known. However, conventional methods of preparation of these structures for their use and production in the pharmaceutical industry are difficult since these methods are usually multi-step and involve high amount of organic solvent. Furthermore, some processes need extreme conditions, which can lead to an increase of heterogeneity of particle size and degradation of the drug. An alternative for drug delivery system production is the utilization of supercritical fluid technique. Lipid particles produced by supercritical fluid have shown different physicochemical properties in comparison to lipid particles produced by classical methods. Such particles have shown more physical stability and narrower size distribution. So, in this paper, a critical overview of supercritical fluid-based processes for the production of lipid micro- and nanoparticles is given and the most important characteristics of each process are highlighted.

RESUMO: "Atividade imunomoduladora e antibacteriana de extratos de espécies da família Rutaceae." A família Rutaceae apresenta espécies vegetais muito bem distribuídas no Semi-Árido Brasileiro e comumente usadas em medicina popular. Espécies dessa família tem diversas atividades biológicas descritas na literatura. Neste trabalho, atividades imunomoduladora e bactericida são descritas para o extrato acetato de etila e clorofórmico de três espécies da família (Esenbeckia grandiflora Mart., Pilocarpus spicatus A.St.-Hil. e Galipea simplicifolia Schult.). Todas as amostras foram inicialmente avaliadas quanto à sua citotoxicidade, com objetivo de determinar a LC50. O potencial imunomodulador foi avaliado em culturas de esplenócitos murinos estimulados ou não com concanavalina A e também em reação mista linfocitária (RML),usando também esplenócitos de camundongos BALB/c (H-2 d ) imunizados com esplenócitos de camundongos C57Bl/6 (H-2 b ). Quatro amostras tiveram os mais elevados valores percentuais de inibição da proliferação de linfócitos ativados pela concanavalina A e foram avaliados em RML. A atividade antibacteriana dos extratos foi também avaliada e a concentração mínima inibitória (CMI) para duas amostras ativas foi de 1.0 e 5.0 mg/mL, respectivamente para as espécies Esenbeckia grandiflora Mart. and Galipea simplicifolia Schult. Assim, os dados aqui apresentados reforçam informações da literatura científica relacionados à atividade biológica para muitas espécies da família Rutaceae e incentivam outros estudos com estas visando descobrir substâncias ativas, potenciais candidatas a novos fármacos.Unitermos: Atividade imunomoduladora, Rutaceae, atividade antibacteriana. ABSTRACT:Rutaceae is a taxon with species very well distributed in Brazilian semi-arid area, commonly used in folk medicine. Species from this genus have diverse biological activity described in literature. In this work, immunomodulatory and bactericidal activity are described for chloroform and ethyl acetate extracts of three of them (Esenbeckia grandiflora Mart., Pilocarpus spicatus A.St.-Hil. and Galipea simplicifolia Schult.). Initially all the samples had their cytotoxicity evaluated, aiming to determine the LC50. The immunomodulatory potential was evaluated in cultures of murine splenocytes stimulated or not with concanavalin A and in a mixed lymphocyte reaction (MLR) using splenocytes from BALB/c (H-2 d ) mice immunized with splenocytes from C57Bl/6 (H-2 b ) mice. Four samples had higher values of lymphoproliferation inhibition in concanavalin A-stimulated cultures and were evaluated in MLR. The antibacterial activity of extracts was also evaluated and the minimal inhibitory concentrations (MIC) for two active samples were 1.0 and 5.0 mg/ml for extracts from Esenbeckia grandiflora Mart. and Galipea simplicifolia Schult., respectively. Thus, our results reinforce data of literature relating biological activity for many species of the Rutaceae family and encourage studies with these species aiming to discover active compounds, candidates to n...

Particulate formulations can significantly increase both potency and safety profiles of opioids.

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