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Novel biocompatible systems suitable for the controlled release of active ingredients are under the spotlight within the last few years. The present investigation focuses on the preparation of nanoparticles (NPs) based on the amphiphilic copolymer pullulan‐graft‐poly(Z‐L‐lysine) bearing different amounts of lysine (10, 20, and 30 wt%), and on the evaluation of their ensuing viability to encapsulate the hydrophobic nonsteroidal anti‐inflammatory drug indomethacin (INDO). The copolymers are synthesized by ring‐opening polymerization, characterized by NMR and FTIR, and their critical aggregation concentration is determined by fluorescence. The NPs are prepared with and without INDO using different copolymer/solvent ratios and INDO/copolymer ratios. The hydrodynamic diameter and polydispersity of the NP suspensions are monitored by dynamic light scattering for 30 days. Their sizes vary between 208 and 338 nm, and some reach the micrometric range (19–73 μm). INDO‐free NPs are identified as spherical‐shaped by atomic force microscopy. Two formulations are tested in terms of encapsulation efficiency (EE = 43%–89%), and the drug crystallinity (DC = 7%–27%) which is determined by differential scanning calorimetry, indicating a reduction with respect to pristine INDO. The results suggest that the copolymers prepared herewith have potential to be applied as carriers for new drug delivery systems of class II drugs. [ABSTRACT FROM AUTHOR]

Pullulan is a biopolymer used in food industry produced by Aureobasidium pullulans from starch. In the present work, sugarcane bagasse (SCB) hydrolysate was evaluated as an alternative substrate in fermentation process assisted by blue LED lights. The best fermentation conditions in Erlenmeyer flasks were 25.3 °C, stirring speed of 232 rpm and yeast extract concentration of 1.88 g/L, yielding 25.19 g/L of pullulan, that corresponded to yield of 0.48 g/g and 0.28 g/(L·h) of volumetric productivity. By using a column bubble photobioreactor, similar yield values were obtained. Thermal properties of the produced pullulan as glass transition (Tg) and melting (Tm) temperatures were 38 °C and 160 °C, respectively, which were similar to the corresponding values of commercial food grade pullulan. Therefore, SCB hydrolysate is a promising substrate to produce good quality pullulan (86% of purity) with application in food industry, besides to represent a new alternative for biorefineries., (Copyright © 2019 Elsevier B.V. All rights reserved.)