Azelaic acid is a dicarboxylic acid containing nine C atoms, industrially obtained from oleic acid. Besides its important properties and pharmacological applications, as an individual compound, azelaic acid has proved to be a valuable bio-based monomer for the synthesis of biodegradable and sustainable polymers, plasticizers and lubricants. This review discusses the studies and the state of the art in the field of the production of azelaic acid from oleic acid, the chemical and enzymatic synthesis of bio-based oligo and polyester and their properties, including biodegradability and biocompostability.

Azelaic acid (AzA), a saturated dicarboxylic acid, is indicated for the treatment of acne vulgaris, rosacea, melasma, and post-inflammatory hyperpigmentation. Its antimicrobial, anti-inflammatory, and antimelanogenic properties support its use; however, its poor aqueous solubility and limited skin permeability constrain its optimal topical delivery. This review summarizes clinical evidence and advances in formulations—including conventional vehicles, polymeric/lipid nanocarriers, and deep eutectic solvent (DES) systems—to promote more effective and well-tolerated use. Across indications, 15–20% azelaic acid (AzA) formulations produced clinically meaningful improvements with mild, transient local irritation. For acne vulgaris, reductions in inflammatory and noninflammatory lesions were comparable to those of topical retinoids/adapalene, and tolerability was superior in some studies. For rosacea, the 15% gel formulation was comparable to metronidazole in reducing papules, pustules, and erythema while maintaining negligible systemic exposure. In melasma and other dyschromias, 20% cream demonstrated efficacy similar to hydroquinone, exhibiting a favorable safety profile. Advanced delivery systems, including liposomes, niosomes/ethosomes, nanostructured lipid carriers, microemulsions, nanosponges, and DES platforms, increased AzA solubilization, cutaneous deposition, and stability. This enabled dose-sparing strategies and improved adherence. Data on AzA cocrystals and ionic salts suggest additional control over release and irritation. AzA remains a versatile and well-tolerated dermatologic agent whose performance is strongly vehicle-dependent. Rational selection and engineering of carriers, particularly DES-integrated polymeric and lipid systems, can mitigate solubility and permeability limitations, enhance skin targeting, and reduce irritation in the treatment of acne and rosacea.

The study reports the enzymatic synthesis of bio-based oligoesters and chemo-enzymatic processes for obtaining epoxidized bioplasticizers and biolubricants starting from cardoon seed oil. All of the molecules had M_W below 1000 g mol⁻¹ and were analyzed in terms of marine biodegradation. The data shed light on the effects of the chemical structure, chemical bond lability, thermal behavior, and water solubility on biodegradation. Moreover, the analysis of the biodegradation of the building blocks that constituted the different bio-based products allowed us to distinguish between different chemical and physicochemical factors. These hints are of major importance for the rational eco-design of new benign bio-based products. Overall, the high lability of ester bonds was confirmed, along with the negligible effect of the presence of epoxy rings on triglyceride structures. The biodegradation data clearly indicated that the monomers/building blocks undergo a much slower process of abiotic or biotic transformations, potentially leading to accumulation. Therefore, the simple analysis of the erosion, hydrolysis, or visual/chemical disappearance of the chemical products or plastic is not sufficient, but ecotoxicity studies on the effects of such small molecules are of major importance. The use of natural feedstocks, such as vegetable seed oils and their derivatives, allows the minimization of these risks, because microorganisms have evolved enzymes and metabolic pathways for processing such natural molecules.

This study investigates the bioactive properties of different extracts of cardoon leaves in rescuing neuronal development arrest in an in vitro model of Rett syndrome (RTT). Samples were obtained from plants harvested at different maturity stages and extracted with two different methodologies, namely Naviglio^® and supercritical carbon dioxide (scCO₂). While scCO₂ extracts more hydrophobic fractions, the Naviglio^® method extracts phenolic compounds and less hydrophobic components. Only the scCO₂ cardoon leaves extract obtained from plants harvested in spring induced a significant rescue of neuronal atrophy in RTT neurons, while the scCO₂ extract from the autumn harvest stimulated dendrite outgrowth in Wild-Type (WT) neurons. The scCO₂ extracts were the richest in squalene, 3ß-taraxerol and lupeol, with concentrations in autumn harvest doubling those in spring harvest. The Naviglio^® extract was rich in cynaropicrin and exerted a toxic effect at 20 µM on both WT and RTT neurons. When cynaropicrin, squalene, lupeol and 3ß-taraxerol were tested individually, no positive effect was observed, whereas a significant neurotoxicity of cynaropicrin and lupeol was evident. In conclusion, cardoon leaves extracts with high content of hydrophobic bioactive molecules and low cynaropicrin and lupeol concentrations have pharmacological potential to stimulate neuronal development in RTT and WT neurons in vitro.