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The use of agricultural residues for the production of bio-oil is an important alternative to the use of fossil fuels. In this study, the Caupi bean pod (Vigna unguiculata) was characterized and used as biomass in the production of bio-oil. This biomass was evaluated in terms of physicochemical, morphological (scanning electron microscopy (SEM)), and thermal (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC)) characterization, lignocellulosic composition, and pyrolysis processes. The pyrolysis was carried out in a stainless steel fixed-bed reactor (260 mm in length and 60 mm in diameter) under atmospheric nitrogen pressure. Pyrolysis was conducted at 550, 600, and 700 °C and N 2 gas flow of 2, 5, and 7 mL min-1. The chemical composition of the bio-oils was studied through CHN, TGA, Fourier-transform infrared spectroscopy (FTIR), and gas chromatography-mass spectrometry (GC-MS). The results confirmed the bean pod's potential in the thermochemical process. The thermogravimetric analyses demonstrate that there can be a relationship between the components of the principal biomass (cellulose, hemicellulose, and lignin) and the compounds present in the bio-oil. The obtained bio-oils represent bio-products that are rich in compounds of several chemical classes with relevant commercial value such as acids (palmitic, linoleic, oleic, and stearic), alcohols (ethylene glycol), sugars (levoglucosan), and phenols (guaiacol, catechol, phenol, and pyrocatechol).

Lipases são enzimas que vêm se destacando no cenário da biotecnologia, principalmente devido a sua capacidade em catalisar reações de hidrólise e de síntese. As lipases são produzidas por microrganismos, animais e vegetais, porém as de origem microbiana são atualmente as mais utilizadas industrialmente. Dentre os microrganismos produtores de lipases estão os fungos filamentosos, as bactérias e as leveduras. O presente trabalho objetivou o isolamento e seleção de bactérias produtoras de lipase, bem como o estudo da produção da enzima usando resíduos provenientes da agroindústria. As amostras para o isolamento foram coletadas em uma planta piloto de biodiesel. Os microrganismos foram isolados e posteriormente submetidos a testes de detecção da atividade lipásica. Após o processo de seleção, os isolados que apresentaram maior índice enzimático (IE), foram utilizados para o estudo da produção de lipase utilizando bagaço de cana-de-açúcar e bagaço de mandioca. Nesse estudo foram isolados 16 microrganismos, sendo que 75% apresentaram atividade lipolítica. Dentre os isolados selecionados como produtores de lipase, a máxima produção foi atingida com a cepa 8A quando utilizado o bagaço de mandioca durante 48 h de fermentação.

The search for new biomaterials has increased continuously in recent years and, in this context, the application of polypyrrole (PPy) as a promising material for this function has been reported as a result of positive responses, such as bioactivity and biocompatibility. In this study, PPy was obtained through modifications/adaptations made in methodologies of previous papers, which focused mainly on conductive properties. The use of additives in the synthesis significantly improves the application in the biomedical area, which depends directly on a diversity of structural and morphological parameters. Here, physicochemical characterization was helpful to determine PPy structures and morphologies of the resulting samples. The addition of phytic acid (PA) and methyl orange (MO) directly influenced not only the particle morphology and size, but also the antibacterial activity and cytotoxicity. The results of antibacterial activity against Staphylococcus aureus and Escherichia coli as well as the negligible cytotoxicity of PPy obtained here indicate a wide applicability of the materials in wound dressing and tissue engineering.