Search results for "photoxidation"
showing 5 items of 5 documents
Natural phenolic compounds: Anti-oxidants or pro-oxidants for biopolyesters?
2018
In this work, different naturally occurring phenolic compounds, such as Thymol (Th), Vanillic acid (VA) and Ferulic Acid (FA), have been considered as UV stabilizers against the photo-oxidative degradation of polylactic acid (PLA). Particularly, in order to explore the effectiveness of the naturally occurring stabilizers, thin PLA-based films, containing different amount of the stabilizers, have been formulated and subjected to accelerate UVB exposure. The preliminary characterizations suggest that the all considered stabilizers exert a plasticizing action and the overall crystallinity of the samples is slightly reduced. If the considered stabilizers are added at low concentration, they exe…
Possible role of mannitol as an oxygen radical scavenger in olive
2011
Along with mannose and sucrose, olive produces large amounts of mannitol in photosynthesizing leaves. Leaf mannitol shows large variation among olive genotypes and Sicilian cultivars with different leaf mannitol content were used in our trials to see whether mannitol may function as an additional non-enzymatic system to protect cells from oxygen radicals and photosystem damage. In one experiment, entire shoots of 'Passulunara', 'Castriciana', 'Nocellara del Belice', and 'Moresca' olive trees were taken to a greenhouse, and mature leaves were treated with paraquat solution, which generates oxygen radicals in presence of light. After 48 hours leaves were sampled, photographed and percent of n…
Formulation of Agricultural Films by Using of the Recycled Polymers: Resistance to the Photoxidation
2009
Quercetin as natural stabilizing agent for bio-polymer
2014
The introduction of antioxidants in polymers is the main way to prevent or delay the degradation process. In particular natural antioxidants receive attention in the food industry also because of their presumed safety. In this work bio-polymers, i.e. a commercial starch-based polymer (Mater-Bi®) and a bio-polyester (PLA), and a bio-polyether (PEO) were additivated with quercetin, a natural flavonoid antioxidants, in order to formulate bio-based films for ecosustainable packaging and outdoor applications. The photo-oxidation behavior of unstabilized and quercetin stabilized films was analyzed and compared with the behavior of films additivated with a commercial synthetic light stabilizer. Th…