Obtenção de triacetato de celulose a partir do bagaço de cana-deaçúcar para revestimento de micropartículas de goma gelana e avaliação do seu perfil de liberação in vitro e da mucoadesão ex vivo

Oral route of administration is considered to be the most comfortable, safe and greater adaptation for patients. But, oral route presents some disadvantages such as drugs bioavailability and side effects on the stomach. Some technologies are studied to soften and/or resolve these problems, such as coating with polymeric films, which are able to protect the pharmaceutical form of the acid stomachic environment and to act in the drug release, and mucoadhesive systems, which allow the pharmaceutical form remains a greater time interval in the intestine, increasing the effectiveness of the drug. Cellulose triacetate (CTA) films were produced from cellulose extracted from sugar cane bagasse. The films were prepared with different morphologies (with and without water, acting as non-solvent) and concentrations (3, 6.5 and 10%) of CTA and characterized using scanning electron microscopy (SEM), water vapor permeability (WVP), puncture resistance (PR), enzymatic digestion (DE), and mucoadhesive force evaluation (MF). Microscopy showed the formation of symmetric and asymmetric morphologies. WVP data showed that more concentrated films have higher values for WVP; moreover, asymmetric films had higher values than symmetric films. PR measurements showed that symmetric membranes are more resistant than asymmetric ones. More concentrated films were also more puncture resistant, except for symmetric membranes with CTA concentrations of 6.5 and 10% that did not show significant differences. All of the films presented large mucoadhesive capacities independent of their morphology and CTA concentration. From the results of WVP and RP, a symmetric filme with 6.5% CTA showed better ability and mechanical resistance, therefore, was selected to serve as coating of gellan gum (GG) particles incorporating ketoprofen (KET), which was confirmed by SEM. The selected film presented low values in measurements of the swelling index (SI) and in a dissolution test (DT). TGA analysis showed that the CTA coating does not influence the thermal stability of the particles and there is no incompatibility evidence between CTA, GG and KET. Coated particles released 100% of the ketoprofen in 24 h, while uncoated particles released the same amount in 4 h. The results of this study highlight the potential of CTA in the development of new controlled oral delivery systems.

Diagnóstico ambiental da área de influência do complexo sucroalcooleiro Usina Vale do São Simão Ltda

One of the most widespread renewable energy sources in Brazil is ethanol, from sugarcane, therefore, the sugar and alcohol sector is expanding, with positive impacts for the economy of the country. Sugar cane was introduced in Brazil as a crop during its colonization, for the production of sugar, and put the country in the global scenario. The expansion of this crop occurred in the seventies, to reduce the reliance in fossil energy sources and to stimulate the development of the agricultural activity. Thus, the federal government has promoted the sugar cane crop and the production of ethanol as a fuel. However, it is important to minimize possible impacts that the crop may cause to the environment. Sugar cane has expanded in the frontiers of the mesoregion of Triângulo Mineiro and Alto Paranaíba-MG, and, in this perspective, the agroindustrial complex known as Companhia Energética Vale do São Simão Ltda., with the Mill located in the county of Santa Vitória, Minas Gerais, was adopted to evaluate the environmental impacts caused by the sugarcane in the area of influence of the mill. The mill has a polygonal area corresponding to 53,525.20 hectares, and for its establishment a Study and Report of Environmental Impacts (EIA/RIMA) was presented, as required as an environment protection instrument by the Environment National Policy (Law nº 6.938/81), and detailed by the Resolution CONAMA nº 01/1986. These studies pointed that native vegetation fragments in the Area of Influence of the Mill, before its implantation, corresponded to approximately 20.7% of the area. Therefore, this study evaluated the impacts of the installation of Usina Vale do São Simão, between 2007 and 2012, determining its reflex on the environmental regularization of the farms, and the vegetation fragments existing in the area, in the recovery and recomposition of areas defined as Legal Reserve and Permanent Preservation. Previous studies of the area were analyzed, soil use and occupation was mapped for the years 2007 and 2012, and the areas of permanent preservation and native vegetation fragments were marked. In general, there was a decline in native vegetation coverage in the period, although it cannot be stated that such reduction was a direct effect of the milling activity. Therefore, the legal requirement of preserving such areas was not capable of bringing the positive effects of protection and recovery as demanded by the Law, highlighting that the current legislation was not enough to protect such areas.