Brazilian plant extracts belonging to 16 species of 5 different families (71 extracts) were tested against the stable DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free-radical. The ability to scavenge DPPH radical was measured in these experiments by the discoloration of the solution. Ginkgo biloba and rutin, commonly used as antioxidants for medical purposes, were used as standards. Based on our results, we can say that as a general rule the ethanol extracts of plants belonging to the Verbenaceae family showed lower EC(50) values than the other plant extracts. Among the partitions, the more polar ones (ethyl acetate and n-butanol) are those that generally have higher antioxidant activity (AA).

Lately several naturally occurring peptides presenting antimicrobial activity have been described in the literature. However, snake venoms, which are an enormous source of peptides, have not been fully explored for searching such molecules. The aim of this work is to review the basis of antimicrobial mechanisms revealing snake venom as a feasible source for searching an antibiotic prototype. Therefore, it includes (i) a description of the constituents of the snake venoms involved in their main biological effects during the envenomation process; (ii) examples of snake venom molecules of commercial use; (iii) mechanisms of action of known antibiotics; and (iv) how the microorganisms can be resistant to antibiotics. This review also shows that snake venoms are not totally unexplored sources for antibiotics and complementary and alternative medicine (CAM).

Abstract. The aim of the present work was to use GastroPlus™ software for the prediction of pharmacokinetic profiles and in vitro-in vivo correlation (IVIVC) as tools to optimize the development of new generic medications. GastroPlus™ was used to simulate the gastrointestinal compartment and was based on the advanced compartmental absorption and transit model. Powder dissolution and efavirenz tablet dissolution studies were carried out to generate data from which correlation was established. The simulated plasma profile, based on the physicochemical properties of efavirenz, was almost identical to that observed in vivo for biobatches A and B. A level A IVIVC was established for the dissolution method obtained for the generic candidate using the Wagner-Nelson (r 2 =0.85) and for Loo-Riegelman models (r 2 =0.92). The percentage of fraction absorbed indicated that 0.5% sodium lauryl sulfate may be considered a biorelevant dissolution medium for efavirenz tablets. The simulation of gastrointestinal bioavailability and IVIVC obtained from immediate-release tablet formulations suggests that GastroPlus™ is a valuable in silico method for IVIVC and for studies directed at developing formulations of class II drugs.KEY WORDS: bioavailability; computational simulation; efavirenz; GastroPlus™; in vivo-in vitro correlation.

-Prickly palm cactus husk was used as a solid-state fermentation support substrate for the production of cellulolytic enzymes using Aspergillus niger and Rhizopus sp. A Box-Behnken design was used to evaluate the effects of water activity, fermentation time and temperature on endoglucanase and total cellulase production. Response Surface Methodology showed that optimum conditions for endoglucanase production were achieved at after 70.35 h of fermentation at 29.56°C and a water activity of 0.875 for Aspergillus niger and after 68.12 h at 30.41°C for Rhizopus sp. Optimum conditions for total cellulase production were achieved after 74.27 h of fermentation at 31.22°C for Aspergillus niger and after 72.48 h and 27.86°C for Rhizopus sp. Water activity had a significant effect on Aspergillus niger endoglucanase production only. In industrial applications, enzymatic characterization is important for optimizing variables such as temperature and pH. In this study we showed that endoglucanase and total cellulase had a high level of thermostability and pH stability in all the enzymatic extracts. Enzymatic deactivation kinetic experiments indicated that the enzymes remained active after the freezing of the crude extract. Based on the results, bioconversion of cactus is an excellent alternative for the production of thermostable enzymes.Keywords: Filamentous fungi. Response surface methodology. Bioprocesses. Semi-arid region. Enzymatic characterization. PRODUÇÃO E CARACTERIZAÇÃO DE ENZIMAS CELULOLÍTICAS POR ASPERGILLUS

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Prickly palm cactus husk was used as a solid-state fermentation support-substrate for production of the ligninolytic enzymes laccase, peroxide manganese, and lignin peroxidase by . Effects of water activity, temperature, and fermentation time on enzymatic production were evaluated using a central composite rotatable design. Response surface methodology revealed that maximum enzyme production was achieved at 73.38 h of fermentation, a water activity of 0.87 A, at 28.74°C for laccase, at 65.33 h, 0.89 A, and 28.96°C for lignin peroxidase, and at 70.44 h, 0.91 A, and 28.84°C for manganese peroxidase. Optimized enzyme production was 9,023.67 UI/L for laccase, 2,234.75 UI/L for lignin peroxidase, and 8,534.81 UI/L for manganese peroxidase. Thermostability and pH stability were observed for all enzymes. Enzymatic deactivation kinetic experiments indicated that enzymes remained active after freezing of crude extracts.

Este trabalho apresenta uma revisão bibliográfica de publicações em periódicos a partir do mapeamento de palavraschave, autores e obras mais citadas sobre o ensino de química com enfoque CTS no Brasil. Para o desenvolvimento desta pesquisa, foram consultados 244 artigos encontrados em 31 revistas brasileiras de ensino e educação, indexadas com Qualis A1, A2 e B1 pela Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), publicados de 1996 a 2016. A fim de estabelecer um recorte metodológico, pesquisou-se neste conjunto trabalhos relacionados ao ensino de química, resultando em 41 artigos que constituíram o objeto desta pesquisa. A partir da análise das informações, verificou-se que o acrônimo CTS foi a palavra-chave de maior relevância dentro da área. Além disso, foi feito um estudo sobre a comunicação entre os autores desses artigos, com destaque para as pesquisadoras Carmem Lúcia Costa Amaral, Vânia Gomes Zuin e Maria DeLourdes Maciel, que são as que estabelecem maior relação com os demais autores dos textos analisados. O estudo realizado revelou ainda que Wildson Santos, além de ser o autor mais citado nesse universo, tem a obra Educação em Química: compromisso com a cidadania, em parceria com Roseli Pacheco Schnetzler, como a mais referenciada na área de ensino de química com enfoque CTS no Brasil.