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One of the main challenges to improve the quality of Brazilian education is to promote reading and an understanding of what is read. This situation is more complex in Youth and Adult Education, which has focused on students who exhibited academic failure in mainstream classes or had not engaged in reading and writing for many years. In addition to adolescents, adults and elderly individuals have the same interests when they are in school; however, the identification of a way to engage these different audiences is a challenge. Thus, we propose reading newspapers online to generate an interest in reading, as well as determining how to select updated texts that are able to draw the attention of students. The findings indicated 100% of the students were satisfied with the activity. Nevertheless, when the times of reading performed in the Educational Computer Laboratory and classroom were compared, the evaluation that employed computer tools was far superior to the classroom. We conclude that although online newspaper reading is quite simple and easy to perform, it is an important tool capable of stimulating and developing the taste and habit of reading and is effective for different audiences. http://dx.doi.org/10.18226/23185279.v5iss2p51

Hyperglycaemia exacerbates the production of reactive oxygen species (ROS), contributing to the multiple complications associated with diabetes. Mitochondrial dysfunction is also known to be associated with diabetes. Therefore, the aim of this work was to study the effect of Pleurotus albidus extract on the mitochondrial dysfunction induced by hyperglycaemia in EA.hy926 endothelial cells. The results showed that P. albidus treatment prevented the increase in the activity of complex I of the electron transport chain and minimized the ROS production induced by hyperglycaemia. In addition, the extract minimized oxidative damage to lipids and proteins, caused an imbalance in the antioxidant enzyme activities of superoxide dismutase and catalase, and decreased the nitric oxide levels induced by hyperglycaemia. These data contribute to our understanding of the mitochondrial disorder induced by hyperglycaemia as well as establishing the conditions required to minimize these alterations.

Penicillium echinulatum S1M29 is a mutant with cellulase and xylanase production comparable to the most studied microorganisms in the literature. However, its potential to produce these enzymes has not been fully investigated. This study aimed at optimizing salt and urea concentrations in the mineral solution, employing the response surface methodology. A 25-1 Fractional Factorial Design and a 23 Central Composite Design were applied to elucidate the effect of salts and urea in enzyme production. Lower concentrations of KH2PO4 (2.0 g.L-1), (NH4)2SO4 (1.4 g.L-1), MgSO4.7H2O (0.375 g.L-1) and CaCl2 (0.375 g.L-1) were most suitable for the production of all enzymes evaluated. Nevertheless, higher concentrations of urea (0.525 g.L-1) gave the best results for cellulase and xylanase production. The maximum FPase (1,5 U.m.L-1), endoglucanase (7,2 U.m.L-1), xylanase (30,5 U.m.L-1) and β-glucosidase (4,0 U.m.L-1) activities obtained with the planned medium were, respectively, 87, 16, 17 and 21% higher when compared to standard medium. The experimental design contributed to adjust the concentrations of minerals and urea of the culture media for cellulase and xylanase production by P. echinulatum, avoiding waste of components in the medium.

The high cost of the enzymes used for the hydrolysis of lignocellulosic biomass is one of the bottlenecks in the production of second-generation ethanol and the use of local biomass, such elephant grass, can help to reduce this cost. In this investigation elephant grass biomass was evaluated as a carbon and inducer source of production of cellulases and xylanases by the fungus Penicillium echinulatum strain 9A02S1 in solid-state cultivation. The highest filter paper activity (13.26 U.g-1 dry matter) and β-glucosidase activity (138.34 U.g-1 dry matter) were obtained on the fifth day of cultivation, in medium containing biomass pre-treated with sulfuric acid and untreated, respectively. The highest endoglucanase activity was 158.44 U.g-1 dry matter in the presence of elephant grass pre-treated with sulfuric acid. The xylanase activity was highest with medium that was formulated with 75% untreated elephant grass and 25% wheat bran (372.62 U.g-1 dry matter). In conclusion, the results showed that it is possible to obtain large amounts of cellulases and xylanases using a cosmopolitan and very low cost substrate such as elephant grass.

Pleurotus species secrete phenol oxidase enzymes: laccase (Lcc) and manganese peroxidase (MnP). New genotypes of these species show potential to be used in processes aiming at the degradation of phenolic compounds, polycyclic aromatic hydrocarbons and dyes. Hence, a screening of some strains of Pleurotus towards Lcc and MnP production was performed in this work. Ten strains were grown through solid-state fermentation on a medium based on Pinus spp. sawdust, wheat bran and calcium carbonate. High Lcc and MnP activities were found with these strains. Highest Lcc activity, 741 ± 245 U gdm(-1) of solid state-cultivation medium, was detected on strain IB11 after 32 days, while the highest MnP activity occurred with strains IB05, IB09, and IB11 (5,333 ± 357; 4,701 ± 652; 5,999 ± 1,078 U gdm(-1), respectively). The results obtained here highlight the importance of further experiments with lignocellulolytic enzymes present in different strains of Pleurotus species. Such results also indicate the possibility of selecting more valuable strains for future biotechnological applications, in soil bioremediation and biological biomass pre-treatment in biofuels production, for instance, as well as obtaining value-added products from mushrooms, like phenol oxidase enzymes.

The main limitation to the industrial scale hydrolysis of cellulose is the cost of cellulase production. This study evaluated cellulase and xylanase enzyme production by the cellulolytic mutantPenicillium echinulatum9A02S1 using pretreated sugar cane bagasse as a carbon source. Most cultures grown with pretreated bagasse showed similar enzymatic activities to or higher enzymatic activities than cultures grown with cellulose or untreated sugar cane bagasse. Higher filter paper activity (1.253 ± 0.147 U·mL−1) was detected in the medium on the sixth day of cultivation when bagasse samples were pretreated with sodium hydroxide, hydrogen peroxide, and anthraquinone. Endoglucanase enzyme production was also enhanced by pretreatment of the bagasse. Nine cultures grown with bagasse possessed higherβ-glucosidase activities on the sixth day than the culture grown with cellulose. The highest xylanase activity was observed in cultures with cellulose and with untreated sugar cane bagasse. These results indicate that pretreated sugar cane bagasse may be able to serve as a partial or total replacement for cellulose in submerged fermentation for cellulase production usingP. echinulatum,which could potentially reduce future production costs of enzymatic complexes capable of hydrolyzing lignocellulosic residues to form fermented syrups.

The effect of different carbon sources on morphology and cellulase and xylanase production ofPenicillium echinulatumwas evaluated in this work. Among the six carbon sources studied, cellulose and sugar cane bagasse were the most suitable for the production of filter paper activity, endoglucanases, xylanases, andβ-glucosidases. However, sucrose and glucose showedβ-glucosidase activities similar to those obtained with the insoluble sources. The polyacrylamide gels proved the enzymatic activity, since different standards bands were detected in the media mentioned above. Regarding morphology, it was observed that the mycelium in a dispersed form provided the greatest enzymatic activity, possibly due to greater interaction between the substrate and hyphae. These data are important in understanding the physiology of fungi and could contribute to obtaining enzyme with potential application in the technology of second generation ethanol.

The present work investigated the use of sorbitol as a soluble carbon source, in association with cellulose, to produce cellulases and xylanases in submerged cultures of Penicillium echinulatum 9A02S1. Because cellulose is an insoluble carbon source, in cellulase production, there are some problems with rheology and oxygen transfer. The submerged fermentations containing media composed of 0, 0.25, 0.5, 0.75, and 1% (w/v) sorbitol and cellulose that were added at different times during the cultivation; 0.2% (w/v) soy bran; 0.1% (w/v) wheat bran; and a solution of salts. The highest filter paper activity (FPA) ( IU·mL−1) was obtained on the seventh day in the medium containing 0.5% (w/v) sorbitol and 0.5% (w/v) cellulose added 24 h after the start of cultivation. However, the CMCases showed an activity peak on the sixth day ( IU·mL−1) in the medium containing 0.75% (w/v) sorbitol and 0.75% (w/v) cellulose added after 12 h of cultivation. The xylanases showed the highest activity in the medium with 0.75% (w/v) sorbitol and 0.25% (w/v) cellulose added 36 h after the start of cultivation. This strategy enables the reduction of the cellulose concentration, which in high concentrations can cause rheological and oxygen transfer problems.

Fodder radish (FR) is an oilseed crop with a high potential for biodiesel production due to its high productivity and the quality of its seed oil. FR oil extraction results in a residue that is rich in protein and fiber. In this study, FR cake (FRC) was evaluated as carbon and nitrogen source for the production of cellulases and xylanases using Penicillium echinulatum S1M29 during solid-state cultivation. It was determined that it is possible to partially replace wheat bran (WB) by FRC, resulting in 24.22 ± 0.25U/g Filter Paper Activity (144 hours), 210.5 ± 5.8U/g endoglucanase activity (144 hours), 22.62 ± 0.01U/g (-glucosidase activity (96 hours) and 784.7 ± 70.19U/g xylanase activity (120 hours). These values are equal or higher than the enzymatic activity obtained using WB. These results may contribute to the reduction of the cost of enzymes used in the production of cellulosic ethanol or other biotechnological applications.