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Phosphorylation of starch has resulted in appreciated material properties for applications in drug matrices. This study aimed to obtain and characterize samples of phosphorylated starch with sodium trimetaphosphate (STMP) and sodium tripolyphosphate (STPP). SEM micrographs allowed evidence that in relation to the starch in natura, the samples showed a loss of grain form in addition to formation of particle agglomerates. X-ray diffractograms of these samples indicated amorphization process, with modifications of the peaks in the region between 15 and 20 º 2θ. FTIR spectra of phosphorylated samples showed variations and new bands related to phosphorylation. Through of methylene blue adsorption isotherms it was observed better adjustment adsorptions on phosphorylated sample to Freundlich model. The new biomaterials showed adsorptive capacity of model cationic nature drug, demonstrate potentiality to application in controlled release systems.

Lasiodiplodan, an exopolysaccharide of the (1→6)-β-D: -glucan type, is produced by Lasiodiplodia theobromae MMPI when grown under submerged culture on glucose. The objective of this study was to evaluate lasiodiplodan production by examining the effects of carbon (glucose, fructose, maltose, sucrose) and nitrogen sources (KNO(3), (NH(4))(2)SO(4), urea, yeast extract, peptone), its production in shake flasks compared to a stirred-tank bioreactor, and to study the rheology of lasiodiplodan, and lasiodiplodan's anti-proliferative effect on breast cancer MCF-7 cells. Although glucose (2.05 ± 0.05 g L(-1)), maltose (2.08 ± 0.04 g L(-1)) and yeast extract (2.46 ± 0.06 g L(-1)) produced the highest amounts of lasiodiplodan, urea as N source resulted in more lasiodiplodan per unit biomass than yeast extract (0.74 ± 0.006 vs. 0.22 ± 0.008 g g(-1)). A comparison of the fermentative parameters of L. theobromae MMPI in shake flasks and a stirred-tank bioreactor at 120 h on glucose as carbon source showed maximum lasiodiplodan production in agitated flasks (7.01 ± 0.07 g L(-1)) with a specific yield of 0.25 ± 0.57 g g(-1) and a volumetric productivity of 0.06 ± 0.001 g L(-1) h(-1). A factorial 2(2) statistical design developed to evaluate the effect of glucose concentration (20-60 g L(-1)) and impeller speed (100-200 rpm) on lasiodiplodan production in the bioreactor showed the highest production (6.32 g L(-1)) at 72 h. Lasiodiplodan presented pseudoplastic behaviour, and the apparent viscosity increased at 60°C in the presence of CaCl(2). Anti-proliferative activity of lasiodiplodan was demonstrated in MCF-7 cells, which was time- and dose-dependent with an IC(50) of 100 μg lasiodiplodan mL(-1).

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The aim of this study was to investigate chitosan film behavior during microwave heating for 10 different heating times from 0 to 40 min. Chitosan films were produced by casting. Their structure and properties were investigated with several techniques, including Fourier transform infrared spectroscopy and differential scanning calorimetry, but also by the measurement of the film color and the mechanical properties or by the study of the rheological properties of the rehydrated films. An original technique of gas chromatography (electronic nose) was used to analyze the film odor and highlight the presence of volatile compounds related to the Maillard reaction occurring during film heating. The results show that structural modifications occurred in two steps; this affected the polymer structure, such as the crystallization and chain scission. The appearance of the neoformed compounds was also observed and must be controlled to guarantee the safety of this food-contact packaging material.