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Summary: Seeds and skins from grape pomaces of Pecorello and Mantonico cv underwent extraction (ultrasound–assisted or maceration), in order to obtain added‐value ingredients for the production of a functional pear jam. The antioxidant features of the extracts were tested by in vitro colorimetric assays. Among seeds, Mantonico by maceration (MSC) showed the best results, as well as Mantonico by ultrasound‐assisted extraction (MBs) among skin extracts. The selected extracts were fully characterised by NMR and MS techniques, confirming the presence of many polyphenols, flavonoids and tannins among others. Pectin was then derivatised by the grafting procedure with the active molecules of MBs and MSC. The latter produced the best antioxidant polymer also without toxicity evaluated using Caco‐2 cells and was used for the jam preparation. The functional pear jam showed improved antioxidant performances in comparison with its non‐functional counterparts as well as its maintenance over time (15 days). [ABSTRACT FROM AUTHOR]

Citrus fruits are one of the principal fruits used to produce juices. Over the years, these fruits have been recognized as new health-promoting agents. In this work, food wastes derived from autochthonous citrus fruits of Southern Italy, named Limone di Rocca Imperiale, Arancia Rossa Moro, and Arancia Bionda Tardivo from Trebisacce, were analyzed. After fresh-squeezing juice, peel and pomace were employed to obtain six different extracts using an ultrasound-assisted method in a hydroalcoholic solvent. The extracts were analyzed in terms of qualitative composition, antioxidant properties, and antiproliferative activity on MCF-7, MDA-MB-231, and BJ-hTERT cell lines. GC-MS and LC-ESI-MS analyses showed different compounds: of note, limonin-hexoside, neodiosmin, obacunone glucoside, and diacetyl nomilinic acid glucoside have been identified as limonoid structures present in all the samples, in addition to different polyphenols including naringenin-glucoside, hesperetin-O-hexoside-O-rhamnoside-O-glucoside, diferuloyl-glucaric acid ester, chlorogenic acid, and the presence of fatty acids such as palmitic, myristic, and linoleic acids. These extracts were able to exert antioxidant activity as demonstrated by DPPH and ABTS assays and, although at higher doses, to reduce the cell viability of different solid tumor cell lines, as shown in MTT assays. [ABSTRACT FROM AUTHOR]

Fatty acids and polyphenols represent different classes of pharmacologically active molecules. Hybrid derivatives of these compounds are interesting therapeutic tools. They could be obtained using enzymatic approaches, which allow regioselective derivatizations. In this short note, the pancreatic porcine lipase was employed to mediate the regioselective synthesis of 7-docosahexaenoyl-quercetin was described. The C-7 regioisomer formation was confirmed by 1H-NMR experiment. Generally, in this approach the alcoholic OH- was preferred when present. Nevertheless, in this case, it was demonstrated that the hindrance of the acyl group is a variable to obtain a good regioselectivity in C-7 position, employing only one-step reaction. [ABSTRACT FROM AUTHOR]

Over the years secondary metabolites have been considered as lead molecules both in their natural form and as templates for medicinal chemistry. Some secondary metabolites such as polyphenols and flavan-3-ols exert beneficial effects after a modification by the microbiota. Synthetic precursors of some of these modified compounds, in turn, carried a γ-alkylidenebutenolide moiety which characterizes a large class of bioactive natural products endowed with a wide range of biological activities. For these reasons stereoselective preparation of γ-alkylidenebutenolide continues to be an important issue for organic chemists. Our objective is to synthetize the novel compound (Z)-5-(3′,4′-bis(benzyloxy)benzylidene)furan-2(5H)-one in a stereocontrolled-one-pot reaction. The product was obtained in good yield. Furthermore, the theoretical investigation of the transition states suggests a new procedure to achieve Z-isomer of β-unsubstituted γ-alkylidenebutenolide. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease and food allergies are a growing topic in the field of nutrition science. Polyphenols, which are the most important secondary metabolites of plants, demonstrated to modulate the expression and/or production of numerous proteins, but also to regulate the intestinal ecosystem. In this context, our aim was the investigation of protective effects against the gastrointestinal mucosa of fortified milk kefir obtained by adding seeds extract from Sangiovese cv. Pomace. Methods: An ultrasound-assisted method was used to obtain the extracts. All the extracts were assayed for the antioxidant activity. The best extract was used as an additive of fermented milk kefir to obtain a fortified final product. Kefir samples were analyzed by NMR spectroscopy. The efficiency of the barrier functions was evaluated by measuring trans-epithelial electric resistance (TEER) using a voltmeter. Results: the enriched kefir (Ksgn) possesses higher antioxidant performances compared to the unfortified sample (Kwht). Kwht and Ksgn did not alter Caco-2 TEER in basal condition. [ABSTRACT FROM AUTHOR]

Polyphenols are well-known health promoting agents, but they have some limitations due to their spontaneous oxidation. This evidence has limited their use as drugs in recent years. In this field, several chemical modifications have been proposed to overcome these restrictions; among these, esterification seems to be the preferred modification. Ester derivatives may be able to reduce the bioavailability problems connected to polyphenols. On the other hand, the presence of esterase enzymes in the body guarantees ester hydrolysis, which in turn frees the two molecules that make it up. Lipase-catalyzed esterifications gave birth to several derivatives of flavonoids glycosides, in green conditions. In this short paper, pancreatic porcine lipase was firstly used as a cheap bio-catalyst, to synthesize oleoyl derivatives of quercetin in aglycone form. The results demonstrated how the enzyme is able to promote a regioselective acylation on C-3 position, with high yields and easy purification processes. [ABSTRACT FROM AUTHOR]