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This work reports a novel enzyme-assisted process for lycopene concentration into a freeze-dried tomato matrix and describes the results of laboratory scale lycopene supercritical CO2 (SC-CO2) extractions carried out with untreated (control) and enzyme-digested matrices. The combined use of food-grade commercial plant cell-wall glycosidases (Celluclast/Novozyme plus Viscozyme) allows to increase lycopene (∼153%) and lipid (∼137%) concentration in the matrix and rises substrate load onto the extraction vessel (∼46%) compared to the control. The addition of an oleaginous co-matrix (hazelnut seeds) to the tomato matrix (1:1 by weight) increases CO2 diffusion through the highly dense enzyme-treated matrix bed and provides lipids that are co-extracted increasing lycopene yield. Under the same operative conditions (50 MPa, 86 °C, 4 mL min(-1) SC-CO2 flow) extraction yield from control and Celluclast/Novozyme+Viscozyme-treated tomato matrix/co-matrix mixtures was similar, exceeding 75% after 4.5h of extraction. However, the total extracted lycopene was ∼3 times higher in enzyme-treated matrix than control.

Heat and drought stress have emerged as major constraints for durum wheat production. In the Mediterranean area, their negative effect on crop productivity is expected to be exacerbated by the occurring climate change. Xyloglucan endotransglucosylase/hydrolases (XTHs) are chief enzymes in cell wall remodelling, whose relevance in cell expansion and morphogenesis suggests a central role in stress responses. In this work the potential role of XTHs in abiotic stress tolerance was investigated in durum wheat. The separate effects of dehydration and heat exposure on XTH expression and its endotransglucosylase (XET) in vitro activity and in vivo action have been monitored, up to 24 h, in the apical and sub-apical root regions and shoots excised from 3-day-old seedlings of durum wheat cultivars differing in stress susceptibility/tolerance. Dehydration and heat stress differentially influence the XTH expression profiles and the activity and action of XET in the wheat seedlings, depending on the degree of susceptibility/tolerance of the cultivars, the organ, the topological region of the root and, within the root, on the gradient of cell differentiation. The root apical region was the zone mainly affected by both treatments in all assayed cultivars, while no change in XET activity was observed at shoot level, irrespective of susceptibility/tolerance, confirming the pivotal role of the root in stress perception, signalling and response. Conflicting effects were observed depending on stress type: dehydration evoked an overall increase, at least in the apical region of the root, of XET activity and action, while a significant inhibition was caused by heat treatment in most cultivars. The data suggest that differential changes in XET action in defined portions of the root of young durum wheat seedlings may have a role as a response to drought and heat stress, thus contributing to seedling survival and crop establishment. A thorough understanding of the mechanisms underlying these variations could represent the theoretical basis for implementing breeding strategies to develop new highly productive hybrids adapted to future climate scenarios.

We report the hydrophilic and lipophilic antioxidant activities, as well as the total phenol, flavonoid, tocochromanol (tocopherol and tocotrienol), and carotenoid contents in the edible portion of wild and cultivated varieties of chicory (Cichorium intybusL.) and in the basal rosette leaves of the wild species of poppy (Papaver rhoeasL.), known by natives as “paparina,” collected in the countryside of Salento (South Apulia, Italy). We analyzed (1) two cultivars of chicory, the “Catalogna” harvested in the area between S. Pietro Vernotico and Tuturano (Brindisi) and the “Otrantina” harvested in Otranto (Lecce); (2) two wild chicory ecotypes harvested in S. Pietro Vernotico (Brindisi) and Statte (Taranto), respectively; (3) the basal leaves of wild poppy harvested in Sternatia (Lecce). In all samples, our results showed that the hydrophilic antioxidant activity is, generally, higher than the lipophilic activity. Poppy leaves exhibited the highest hydrophilic and lipophilic antioxidant activities and the highest concentration of total phenols and flavonoids. Tocopherols were detected only as traces. Among the extracted carotenoids, lutein andβ-carotene were the most abundant in all analyzed samples. Total carotenoid content was greater in wild than in cultivated plants.

This study investigated the formation of oxo groups in pure solutions of barley mixed-linkage (1 → 3),(1 → 4)-β- d -glucans (MLGs) incubated in the presence of hydrogen peroxide or Fenton reaction-generated hydroxyl radicals ( OH), and it gives a fingerprint of products obtained after enzymic and acidic hydrolysis of OH-attacked MLG. Hydroxyl radical, but not hydrogen peroxide, introduced a range of NaB3H4-reducible functions into MLG chains. Driselase or lichenase digestion of NaB3H4-reduced MLGs released a complex mixture of 3H-labelled products due to the presence of unusual and incompletely digestible residues in OH-attacked polysaccharide chains. Complete acid hydrolysis of OH-treated MLGs yielded a mixture of 3H-aldoses (mainly glucose, mannose, galactose and allose) deriving from random OH attack at positions 2, 3 or 4 to form glycosulose residues which were NaB3H4-reducible to epimeric mixtures of 3H-aldose residues. Furthermore, the production of [3H]glucitol demonstrated the radical-mediated cleavage of mid-chain glucose residues to create new reducing termini. Oxidative scission of MLGs by hydroxyl radical caused a decrease in molecular weight of about 96%, which was partially inhibited by the addition of DMSO, an OH scavenger. The results can be a starting point for developing an assay to detect changes due to OH attack of MLGs in vivo, or during food processing and storage, based on the chemical or enzymic release of unusual sugar residues such as allose as diagnostic products after reduction/labelling treatment and partial purification (or selective digestion by lichenase) of polymeric material.