Cinzia Pezzella

The development of sustainable biorefineries requires integrated fractionation strategies capable of preserving carbohydrate streams while generating high‐value lignin and bioactive fractions. In this study, olive pomace was valorized through a cascade approach combining optimized microwave‐assisted extraction (MAE) of phenolic compounds, natural deep eutectic solvents (NADES)‐enabled pretreatment, and chemo‐enzymatic modification. MAE enabled recovery of a phenolic‐rich fraction and reduced inhibitory compounds in the residual biomass, improving its suitability for downstream processing. The dephenolized substrate was subsequently subjected to NADES‐based fractionation using acidic, alkaline, and neutral systems, including a laccase‐assisted variant. Pretreatment performance depended on solvent chemistry. The acidic system (ChCl:lactic acid) achieved high delignification (≈68%) but produced restructured lignin with extensive β‐O‐4 cleavage. The alkaline NADES (K ₂ CO ₃ :ethylene glycol) combined high lignin removal (≈75%) with partial preservation of native linkages and solvent‐induced functionalization. The neutral NADES (betaine:glycerol) preserved both polysaccharides and lignin structure, while laccase induced selective oxidative modifications. These differences yielded lignin fractions with distinct structural features suitable for different downstream valorization routes. In parallel, alkaline NADES enabled efficient saccharification with balanced glucose and xylose release, supporting polyhydroxyalkanoate production by Haloferax mediterranei . Overall, this work demonstrates a tunable cascade strategy integrating phenolic recovery, DES fractionation, and lignin structural design for multiproduct lignocellulosic biorefineries.

The formulation of eco-friendly biodegradable packaging has received great attention during the last decades as an alternative to traditional widespread petroleum-based food packaging. With this aim, we designed and tested the properties of polyhydroxyalkanoates (PHA)-based bioplastics functionalized with phloretin as far as antioxidant, antimicrobial, and morpho-mechanic features are concerned. Mechanical and hydrophilicity features investigations revealed a mild influence of phloretin on the novel materials as a function of the concentration utilized (5, 7.5, 10, and 20 mg) with variation in FTIR e RAMAN spectra as well as in mechanical properties. Functionalization of PHA-based polymers resulted in the acquisition of the antioxidant activity (in a dose-dependent manner) tested by DPPH, TEAC, FRAR, and chelating assays, and in a decrease in the growth of food-borne pathogens (Listeria monocytogenes ATCC 13932). Finally, apple samples were packed in the functionalized PHA films for 24, 48, and 72 h, observing remarkable effects on the stabilization of apple samples. The results open the possibility to utilize phloretin as a functionalizing agent for bioplastic formulation, especially in relation to food packaging.

Microalgal biomass represents a very interesting biological feedstock to be converted into several high-value products in a biorefinery approach. In this study, the cyanobacterium Synechocystis sp. PCC6803 was used to obtain different classes of molecules: proteins, carotenoids and lipids by using a cascade approach. In particular, the protein extract showed a selective cytotoxicity towards cancer cells, whereas carotenoids were found to be active as antioxidants both in vitro and on a cell-based model. Finally, for the first time, lipids were recovered from Synechocystis biomass as the last class of molecules and were successfully used as an alternative substrate for the production of polyhydroxyalkanoate (PHA) by the native PHA producer Pseudomonas resinovorans. Taken together, our results lead to a significant increase in the valorization of Synechocystis sp. PCC6803 biomass, thus allowing a possible offsetting of the process costs.

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.