Physicochemical, biological and release studies of chitosan membranes incorporated with Euphorbia umbellata fraction

Abstract Formulations containing chitosan incorporated with methanolic fraction of Euphorbia umbellata (Pax) Bruyns, Euphorbiaceae, were studied aiming future applications of this new material as medicine. In order to investigate potential interactions between chitosan and the methanolic fraction (10, 50 and 100% in relation to the amount of chitosan) physicochemical characterization was performed by scanning electron microscopy, density, differential scanning calorimetry, thermogravimetry, X-ray diffraction, Fourier-transform infrared spectroscopy and colorimetry techniques. The phenolic compounds released from the chitosan membranes were evaluated using the Folin-Ciocalteau quantification method; antioxidant and antimicrobial activity were also studied. Increasing amounts of the methanolic fraction added to polymeric matrix produced different numbers of pores on the surface of the membranes, changes in the calorimetric, spectroscopic and crystalline properties as well as color changes, when compared to the inert membrane. These changes can be attributed to chemical interactions that occurred between the structure of the chitosan and the phenolic compounds present in the studied fraction. The matrix samples incorporated with 50 and 100% of the methanolic fraction presented different release profiles of phenolic compounds from the membranes (controlled manner) and promoted antioxidant and antimicrobial activity.

Chemical and pharmacological investigation of the stem bark of Synadenium grantii.

Based on the fact that Synadenium grantii is used in folk medicine for the treatment of peptic ulcers and inflammatory diseases, this work describes its chemical and pharmacological properties. Pharmacological investigation of the crude bark extract showed a high antioxidant activity over several scavenger systems, such as 2,2'-azino-bis (3-ethylenebenzothiazoline-6-sulfonic acid)• +, 1-diphenyl-2-picrylhydrazyl•, O2 • - , and HOCl, as well as an enzymatic system with human myeloperoxidase and an ex vivo hemolysis system. Furthermore, the oral administration of the crude bark extract was able to reduce carrageenan-induced rat paw edema as effectively as ibuprofen. These biological activities may be associated with the presence of flavonoids and terpenes, as revealed by HPLC and NMR analyses of the crude stem bark extract. The phytochemical investigations in this study resulted in the isolation of friedelin and 3ß-friedelinol for the first time, while euphol and lanosterol were also isolated.

Chemical, enzymatic and cellular antioxidant activity studies of Agaricus blazei Murrill.

Mushrooms possess nutritional and medicinal properties that have long been used for human health preservation and that have been considered by researchers as possible sources of free radical scavengers. In this work, the antioxidant properties of water extracts from Agaricus blazei Murill, produced by maceration and decoction, are demonstrated in vitro. Resistance to oxidation is demonstrated through three mechanisms: i) inhibition of enzymatic oxidative process, with 100% inhibition of HRP (horseradish peroxidase) and MPO (myeloperoxidase); ii) inhibition of cellular oxidative stress, with 80% inhibition of the oxidative burst of polymorphonuclear neutrophils (PMNs); and iii) direct action over reactive species, with 62% and 87% suppression of HOCl and superoxide anion radical (O2• -), respectively. From the data, it was concluded that the aqueous extract of A. blazei has significant antioxidant activity, indicating its possible application for nutraceutical and medicinal purposes.

Experimental periodontitis promotes transient vascular inflammation and endothelial dysfunction.

OBJECTIVES: This study aimed to evaluate the systemic inflammatory response and cardiovascular changes induced by experimental periodontitis in rats. DESIGN: Experimental periodontitis was induced by placing a cotton ligature around the cervix of both sides of mandibular first molars and maxillary second molars in each male rat. Sham-operated rats had the ligature removed immediately after the procedure. Seven, 14 or 28 days after procedure, the effects of acetylcholine, sodium nitroprusside and phenylephrine were evaluated on blood pressure, aortic rings and isolated and perfused mesenteric bed. The blood was obtained for plasma Interleukin-6 (IL-6), C-reactive protein (CRP) and lipid evaluation. The mesenteric vessels were obtained to evaluate superoxide production and nitric oxide synthase 3 (NOS-3) expression. RESULTS: Ligature induced periodontitis reduced endothelium-dependent vasodilatation, a hallmark of endothelial dysfunction. This effect was associated with an increase in systemic inflammatory markers (IL-6 and CRP), worsens on lipid profile, increased vascular superoxide production and reduced NOS-3 expression. It is interesting to note that many of these effects were transitory. CONCLUSION: Periodontitis induced a transient systemic and vascular inflammation which leads to endothelial dysfunction, an initial step for cardiovascular diseases. Moreover, the animal model of periodontitis used here may represent a valuable tool for studying the relationship between periodontitis and endothelial dysfunction.

Estudo fitoquímico de goiaba (Psidium guajava L. ) com potencial antioxidante para o desenvolvimento de formulação fitocosmética / Phytochemical study of guava (Psidium guajava L. ) with potential antioxidant activity aiming at developing a phytocosmetic formulation

Considerando-se a qualidade dos fitoterápicos, é importante salientar que a preocupação com esta questão inclui rigoroso acompanhamento das diferentes etapas do desenvolvimento e produção destes produtos, desde a coleta do vegetal até a disponibilidade do produto final. Neste trabalho, foram realizados o controle da qualidade, o potencial antioxidante como também ensaios biológicos in vitro do fruto da goiabeira (Psidium guajava L.), para o desenvolvimento de uma formulação fitocosmética. Os resultados obtidos mostraram que o fruto apresenta taninos e flavonóides, bem como atividades antioxidante e antimicrobiana. A análise microbiológica não apresentou crescimento de patógenos na formulação desenvolvida entre os outros testes realizados. Destaca-se a importância do estabelecimento do controle da qualidade para as plantas, a fim de que sejam utilizadas para o desenvolvimento de uma formulação fitocosmética segura, eficaz e com qualidade.

Considering the quality of the phytotherapic products, it is important to point out that the concern with this question includes rigorous accompaniment of the different stages of the development and production of these products, since the collection of the vegetable until the availability of the end product. In this work the quality control, the antioxidant potential were performed as also biological assays in vitro of guava fruit (P. guajava L.), for the development of a phytocosmetic formulation. The results had shown that the fruit presents tannins and flavonoids, as well as antioxidant and antimicrobial activities. The microbiological analysis did not present growth of pathogens. The importance of the establishment of the quality control for the plants is relevant, so that they are used for the development of a phytocosmetic formulation considered safe, efficient and with quality.