In this study we report the synthesis and characterisation of cellulose ferulate, lipoate and alpha-tocopherulate, and their ability to inhibit lipid peroxidation in rat-liver microsomal membranes, induced in vitro by two different sources of free radicals: tert-butyl hydroperoxide and 2,2'-azobis-(2-amidinopropane). We also compared the antioxidant efficiency of the ferulate derivatives obtained through two different synthetic runs, and of a tocopherulate derivative prepared from 6-carboxycellulose. This study showed that the designed systems, preserving the antioxidant activity of the free substrates, are more effective in protecting from tert-butyl hydroperoxide than from 2,2'-azobis-(2-amidinopropane). Moreover, the cellulose ferulate with the higher degree of substitution acted as the best antioxidant.

Sustainable polymers from renewable resources are classified as biobased polymers. Poly­(lactic acid) (PLA) is one of the most common biobased polymers applied in the biodegradable plastic industry as a feasible substitute of petrochemical-derived products. Cardanol oil (CA), a renewable resource and relatively low-cost side product of the cashew agro-industry, combined with neat PLA permitted the preparation of plasticized PLA/CA films by means of hot melt extrusion processes. Looking at packaging applications of the functional biobased PLA/CA films, chemical, mechanical, thermal, antioxidant, and barrier properties were studied. Thermal analysis revealed that the PLA glass-transition temperature decreased with the increasing content of CA, indicating that CA worked as a plasticizer for PLA. The presence of CA increased the oxygen transmission through the PLA/CA films; consequently, the permeability values were always appreciably higher for plasticized films. Nevertheless, the CA-plasticized PLA films showed good barrier properties similar to packaging materials commonly used in the food industry today. Release studies from PLA/CA films were carried out in four food simulants (physiological saline solution, ethanol, acetic acid, and isooctane) through spectrophotometric measurements and revealed the release effects only in simulants for fatty foods. Radical scavenging assays indicated the elevated antioxidant activity of CA-incorporated films compared to neat PLA.

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Conversion of CO 2 to reduced products is a promising route to alleviate irreversible climate change. Here we report the synthesis of a Co-based phthalocyanine with pyridine moieties (CoPc-Pyr), which is supported on a carbon electrode and shows Faradaic efficiency ∼90% for CO at 490 mV of overpotential (−0.6 V vs reversible hydrogen electrode (RHE)). In addition, its catalytic activity at −0.7 V versus RHE surpasses other Co-based molecular and metal−organic framework catalysts for CO 2 reduction at this bias. Density functional theory calculations show that pyridine moieties enhance CO 2 adsorption and electron affinity of the Co center by an inductive effect, thus lowering the overpotential necessary for CO 2 conversion. Our study shows that CoPc-Pyr reduces CO 2 at lower overpotential and with higher activity than noble metal electrodes, such as silver.