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A method for estimation of sugarcane (Saccharum spp.) biomass crystallinity using near infrared spectroscopy (NIR) and partial least squares regression (PLS) as an alternative to the standard method using X-ray diffractometry (XRD) is proposed. Crystallinity was obtained using XRD from sugarcane bagasse. NIR spectra were obtained of the same material. PLS models were built using the NIR and crystallinity values. Cellulose crystallinity ranged from 50 to 81%. Two variable selection algorithms were applied to improve the predictive ability of models, i.e. (a) Ordered Predictors Selection (OPS) and (b) Genetic Algorithm. The best model, obtained with the OPS algorithm, presented values of correlation coefficient of prediction, root mean squared error of prediction and ratio of performance deviation equals to 0.92, 3.01 and 1.71, respectively. A scatter matrix among lignin, α-cellulose, hemicellulose, ash and crystallinity was built that showed that there was no correlation among these properties for the samples studied.

This work aimed to develop nanocomposite films of methyl cellulose (MC) incorporated with pediocin and zinc oxide nanoparticles (nanoZnO) using the central composite design and response surface methodology. This study evaluated film physical-mechanical properties, including crystallography by X-ray diffraction, mechanical resistance, swelling and color properties, microscopy characterization, thermal stability, as well as antimicrobial activity against Staphylococcus aureus and Listeria monocytogenes. NanoZnO and pediocin affected the crystallinity of MC. Load at break and tensile strength at break did not differ among films. NanoZnO and pediocin significantly affected the elongation at break. Pediocin produced yellowish films, but nano ZnO balanced this effect, resulting in a whitish coloration. Nano ZnO exhibited good intercalation in MC and the addition of pediocin in high concentrations resulted crater-like pits in the film surfaces. Swelling of films diminished significantly compared to control. Higher concentrations of Nano ZnO resulted in enhanced thermal stability. Nanocomposite films presented antimicrobial activity against tested microorganisms.