Lignin contributes to the rigid structure of the plant cell wall and is partially responsible for the recalcitrance of lignocellulosic materials to enzymatic digestion. Overcoming this recalcitrance is one the most critical issues in a sugar-flat form process. This study addresses the effect of low lignin sugarcane bagasse on enzymatic hydrolysis after liquid hot water pretreatment at 190 °C and 20 min (severity factor: 3.95). The hydrolysis of bagasse from a sugarcane line selected for a relatively low lignin content, gave an 89.7% yield of cellulose conversion to glucose at 40 FPU/g glucan versus a 68.3% yield from a comparably treated bagasse from the high lignin bred line. A lower enzyme loading of 5 FPU/g glucan (equivalent to 3.2 FPU/g total solids) resulted in 31.4% and 21.9% conversion yields, respectively, for low and high lignin samples, suggesting the significance of lignin content in the saccharification process. Further increases in the enzymatic conversion of cellulose to glucose were achieved when the bagasse sample was pre-incubated with a lignin blocking agent, e.g., bovine serum albumin (50 mg BSA/g glucan) at 50 °C for 1 h prior to an actual saccharification. In this work, we have demonstrated that even relatively small differences in lignin content can result in considerably increased sugar production, which supports the dissimilarity of bagasse lignin content and its effects on cellulose digestibility. The increased glucose yields with the addition of BSA helped to decrease the inhibition of non-productive absorption of cellulose enzymes onto lignin and solid residual lignin fractions.

Phytase plays a prominent role in monogastric animal nutrition due to its ability to improve phytic acid digestion in the gastrointestinal tract, releasing phosphorus and other micronutrients that are important for animal development. Moreover, phytase decreases the amounts of phytic acid and phosphate excreted in feces. Bioinformatics approaches can contribute to the understanding of the catalytic structure of phytase. Analysis of the catalytic structure can reveal enzymatic stability and the polarization and hydrophobicity of amino acids. One important aspect of this type of analysis is the estimation of the number of β-sheets and α-helices in the enzymatic structure. Fermentative processes or genetic engineering methods are employed for phytase production in transgenic plants or microorganisms. To this end, phytase genes are inserted in transgenic crops to improve the bioavailability of phosphorus. This promising technology aims to improve agricultural efficiency and productivity. Thus, the aim of this review is to present the characterization of the catalytic structure of plant and microbial phytases, phytase genes used in transgenic plants and microorganisms, and their biotechnological applications in animal nutrition, which do not impact negatively on environmental degradation.

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The searches for new antimicrobial compounds to control the lactic acid bacteria in winemaking are based in the increasing global concern about the chemical preservatives restrictions and the development of super-resistant strains continuously exposed to sulfites in wineries for decades. The antimicrobial activity of the nisin as a biopreservative was studied for Bordô (Ives) and Niágara grape wines from Santa Catarina, Brazil. Measurements of antimicrobial activity were made by well-diffusion assays. From the eleven previously assessed strains of nisinsusceptible lactic bacteria (nisin concentration 1000 IU ml-1), four were selected for definitive assays with nisin (100 IU ml-1) dissolved in the wines. Positive results for inhibition were obtained for the four strains selected. Next, the direct inhibitory action was assessed in wines artificially inoculated and then treated with nisin. After 60 days of storage, there was reduction in the total bacterial population as compared to control, especially in Bordô (Ives) wine, while the physic-chemical parameters were not influenced by the nisin treatment. The inhibitory activity of nisin was not affected when it was dissolved in wine in the antimicrobial assays, and its potential utilization as biopreservative should be able to aid on the control of autochthonous microbiota, but further studies are required to conclude more precisely the nisin effects at long term in wines.