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This work aimed to study the effect of the incorporation of graphene nanoplatelets (GRA 0.5% and 1% ( w / w )) on the matrices of biobased polymers composed of starch-based materials (B20) and poly(butylene succinate) (PBS) using pine rosin (RES) as a compatibilizer. Three formulations were produced (B20/RES/PBS, B20/RES/PBS/GRA0.5%, and B20/RES/PBS/GRA1%), and their mechanical properties (tensile, flexural, hardness, and impact), rheological behavior, thermal properties (thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)), chemical analysis (Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy), and contact angle were evaluated. Hardness (Shore D), tensile, and flexural moduli increased, whereas elongation at break and toughness decreased as GRA content increased. FTIR studies strongly supported the existence of interactions between polymeric matrices and the large surface area of GRA. The viscosity flow curves were well fitted to the Cross-Williams-Landel-Ferry (Cross-WLF) model, and the three formulations exhibited non-Newtonian (shear-thinning) behavior. The analysis of water contact angles indicated that the formulation surfaces have hydrophilic behavior. All the samples are thermally stable, and the results of this study can be used to optimize the application of biobased graphene-based composites for applications in injection molding industries.

Glioblastoma (GBM) is an incurable primary brain tumor with a poor prognosis. Resection, radiation therapy, and temozolomide (TMZ) are insufficient to increase survival, making the treatment limited. Thus, the search for more effective and specific treatments is essential, making plants a promising source for elucidating new anti-glioblastoma compounds. Accordingly, this study investigated the effects of four fractions of hexane and ethyl acetate extract of Annona coriacea Mart., enriched with acetogenins, against GBM cell lines. All four fractions were selectively cytotoxic to GBM cells when compared to TMZ. Moreover, A. coriacea fractions delayed cell migration; reduced cytoplasmic projections, the metalloproteinase 2 (MMP-2) activity; and induced morphological changes characteristic of necroptosis, possibly correlated with the increase in receptor-interacting protein kinase 1 and 3 (RIP-1 and RIP-3), apoptosis-inducing factor (AIF), and the non-activation of cleaved caspase 8. The present findings reinforce that fractions of A. coriacea Mart. should be considered for more studies focusing treatment of GBM.

This work aims to evaluate the influence of two starch-based materials (B16 and B20) on the moisture sorption isotherms, determined at 30, 40, and 50 °C, where B16 contains 5% (w/w) more starch than B20. Thermodynamic functions (differential enthalpy (∆H dif ), differential entropy (∆S dif ), integral enthalpy (Δh int ), integral entropy (ΔS int ), free Gibbs energy (∆G), and spreading pressure (φ)) were used to understand the water-binding behaviors and the energy requirements to remove the moisture content from the surface of these materials. The moisture sorption isotherms exhibited type III behavior, and the Guggenheim-Anderson-de Boer (GAB) model was the most suitable to fit the experimental moisture adsorption data. The adsorption isotherms of microparticles were enthalpy-controlled, with isokinetic temperature values of 221.45 and 279.77 K for B16 and B20, respectively, being higher than the harmonic mean temperature (312.94 K). The values of ∆G were positive (45.274 and 44.307 kJmol -1 for B16 and B20, respectively), indicating a non-spontaneous process. The spreading pressure values increased with increasing water activity (aw) for all isotherms. Higher values of ∆H dif and ∆S dif obtained from B16 confirmed its higher number of sorption sites available for binding with water molecules when compared to B20, making it less suitable for application in the food packaging industry.

The main purpose of this paper is to provide an insight into the biological activities of pyrazole derivatives which contain the carbohydrazide moiety.