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The use of vegetable oils and their derivatives for polymer synthesis has been a major focus in recent years due to their universal availability, low production costs and biodegradability. In this study, the enzymatic synthesis of oligoesters of ricinoleic acid obtained from castor oil combined with three aromatic natural derivatives (cinnamyl alcohol, sinapic acid, and caffeic acid) was investigated. The formation of the reaction products was demonstrated by FT-IR, MALDI-TOF MS and NMR spectroscopy and for the oligo (ricinoleyl)-caffeate the thermal properties and biodegradability in sweet water were analyzed and a rheological characterization was performed. The successful enzymatic synthesis of oligoesters from ricinoleic acid and aromatic monomers using lipases not only highlights the potential of biocatalysis in green chemistry but also contributes to the development of sustainable and biodegradable methods for synthesizing products with potential applications as cosmetic ingredients. [ABSTRACT FROM AUTHOR]

Given the widespread use of esters and polyesters in products like cosmetics, fishing nets, lubricants and adhesives, whose specific application(s) may cause their dispersion in open environments, there is a critical need for stringent eco-design criteria based on biodegradability and ecotoxicity evidence. Our approach integrates experimental and computational methods based on short oligomers, offering a screening tool for the rapid identification of sustainable monomers and oligomers, with a special focus on bio-based alternates. We provide insights into the relationships between the chemical structure and properties of bio-based oligomers in terms of biodegradability in marine environments and toxicity in benchmark organisms. The experimental results reveal that the considered aromatic monomers (terephthalic acid and 2,5-furandicarboxylic acid) accumulate under the tested conditions (OECD 306), although some slight biodegradation is observable when the inoculum derives from sites affected by industrial and urban pollution, which suggests that ecosystems adapt to non-natural chemical pollutants. While clean seas are more susceptible to toxic chemical buildup, biotic catalytic activities offer promise for plastic pollution mitigation. Without prejudice to the fact that biodegradability inherently signifies a desirable trait in plastic products, nor that it automatically grants them a sustainable "license", this study is intended to facilitate the rational design of new polymers and materials on the basis of specific uses and applications. [ABSTRACT FROM AUTHOR]

The treatment of colored wastewater has been paid attention in the recent years because of the high amount of dyes, mostly carcinogenic, discharged into the water. Enzymatic degradation shows several advantages such as: shorter processing time, reduction in sludge volume and ease of controlling the process. In this work, seven different industrial dyes were tested as substrates for horseradish peroxidase. The native enzyme was covalently immobilized onto two types of epoxy-supports, different in spacer length. Among the tested dyes the highest substrate conversions were achieved for Amido Black 10 (AB10). The highest recovered activity was obtained when the epoxy-activated support with longer spacer arm was used. After ten reuse cycles for the degradation of AB10, the covalently bound peroxidase preserved about 80% of the initial activity. [ABSTRACT FROM AUTHOR]

Following the latest developments, bio-based polyesters, obtained from renewable raw materials, mainly carbohydrates, can be competitive for the fossil-based equivalents in various industries. In particular, the furan containing monomers are valuable alternatives for the synthesis of various new biomaterials, applicable in food additive, pharmaceutical and medical field. The utilization of lipases as biocatalysts for the synthesis of such polymeric compounds can overcome the disadvantages of high temperatures and metal catalysts, used by the chemical route. In this work, the enzymatic synthesis of new copolymers of ε-caprolactone and 5-hydroxymethyl-2-furancarboxylic acid has been investigated, using commercially available immobilized lipases from Candida antarctica B. The reactions were carried out in solvent-less systems, at temperatures up to 80 °C. The structural analysis by MALDI TOF-MS, NMR, and FT-IR spectroscopy confirmed the formation of cyclic and linear oligoesters, with maximal polymerization degree of 24 and narrow molecular weight distribution (dispersity about 1.1). The operational stability of the biocatalyst was explored during several reuses, while thermal analysis (TG and DSC) indicated a lower thermal stability and higher melting point of the new products, compared to the poly(ε-caprolactone) homopolymer. The presence of the heterocyclic structure in the polymeric chain has promoted both the lipase-catalyzed degradation and the microbial degradation. Although, poly(ε-caprolactone) is a valuable biocompatible polymer with important therapeutic applications, some drawbacks such as low hydrophilicity, low melting point, and relatively slow biodegradability impeded its extensive utilization. In this regard the newly synthesized furan-based oligoesters could represent a "green" improvement route. [ABSTRACT FROM AUTHOR]