Nobiletin and xanthohumol counteract the TNFα-mediated activation of endothelial cells through the inhibition of the NF-κB signaling pathway.

Angiogenesis, a process characterized by the formation of new blood vessels from pre-existing ones, is a crucial step in tumor growth and dissemination. Given the ability of tumors to interfere with multiple or different molecular pathways to promote angiogenesis, there is an increasing need to therapeutically block tumor progression by targeting multiple antiangiogenic pathways. Natural polyphenols present health-protective properties, which are likely attributed to their ability to activate multiple pathways involved in inflammation, carcinogenesis, and angiogenesis. Recently, increased attention has been addressed to the ability of flavonoids, the most abundant polyphenols in the diet, to prevent cancer by suppressing angiogenesis. Here we investigate the mechanisms by which xanthohumol (the major prenylated flavonoid of the hop plant Humulus lupulus L.) and nobiletin (flavonoid from red-orange Citrus sinensis) can modulate the effects of Tumor Necrosis Factor-α (TNF-α) on human umbilical vein endothelial cells (HUVEC). The results reported in this paper show that xanthohumol and nobiletin pretreatment of HUVEC inhibits the effects induced by TNF-α on cell migration, invasion capability, and colon cancer cell adhesion on the endothelial monolayer. Moreover, the pretreatment reduces metalloproteinases and adhesion molecules' expression. Finally, our results highlight that xanthohumol and nobiletin can counteract the effects of TNF-α on angiogenesis and invasiveness, mainly through Vascular Endothelial Growth Factor and NF-κB pathways. Since angiogenesis plays an important pathological role in the progression of several diseases, our findings may provide clues for developing xanthohumol and nobiletin as therapeutic agents against angiogenesis-associated diseases.

Steroidal Alkaloids from Food Waste of Tomato Processing Inhibit Neuroblastoma Cell Viability.

Nowadays, there is considerable attention toward the use of food waste from food processing as possible sources of compounds with health properties, such as anticancer activity. An example is tomato processing, which is responsible for generating a remarkable amount of waste (leaves, peel, seeds). Therefore, our goal was to evaluate the potential anticancer property of tomato extracts, in particular "Datterino" tomato (DT) and "Piccadilly" tomato (PT), and to study their phytochemical composition. Liquid chromatography with tandem mass spectrometry (LC/MS-MS) results showed that these extracts are rich in alkaloids, flavonoids, fatty acids, lipids, and terpenes. Furthermore, their potential anticancer activity was evaluated in vitro by MTT assay. In particular, the percentage of cell viability was assessed in olfactory ensheathing cells (OECs), a particular glial cell type of the olfactory system, and in SH-SY5Y, a neuroblastoma cell line. All extracts (aqueous and ethanolic) did not lead to any significant change in the percentage of cell viability on OECs when compared with the control. Instead, in SH-SY5Y we observed a significant decrease in the percentage of cell viability, confirming their potential anticancer activity; this was more evident for the ethanolic extracts. In conclusion, tomato leaves extracts could be regarded as a valuable source of bioactive compounds, suitable for various applications in the food, nutraceutical, and pharmaceutical fields.

Anti-Inflammatory and Antioxidant Properties of Dehydrated Potato-Derived Bioactive Compounds in Intestinal Cells.

Inflammation and oxidative stress are always more recognized as responsible for chronic disease at the intestinal level. Currently, a growing interest is addressed to the discovery of diet-derived products which have anti-inflammatory and antioxidant properties. This work aims to characterize the pharmacological potential of dehydrated potatoes. For this purpose, a simulated gastrointestinal digestion was carried out. The bioaccessible peptides were fractionated on the basis of their molecular weight and tested on intestinal epithelial cells (IEC-6) under oxidative and inflammatory conditions. Our results demonstrate that the tested peptide fractions were able to significantly inhibit tumor necrosis factor-α release and cycloxygenase-2 and inducible nitric oxide synthase expression. The tested peptides also showed significant antioxidant activity, being able to both reduce reactive oxygen species (ROS) release, also from mitochondria, and nitrotyrosine formation, and increase the antioxidant response by heme oxygenase-1 and superoxide dismutase expression. Moreover, the peptide fractions were able to significantly increase the wound repair in IEC-6. The obtained results indicate the anti-inflammatory and antioxidant potential of dehydrated potatoes at the intestinal level.

Yield parameters and antioxidant compounds of tomato fruit: the role of plant defence inducers with or without Cucumber mosaic virus infection.

BACKGROUND: The production of fruit and vegetables rich in health-promoting components in an eco-friendly context represents the winning answer to the world population demand for food. In this study, the effects of different treatments on the yield and fruit chemical characteristics of tomato (Solanum lycopersicum L.) are reported. The treatments included three inducers of plant defence responses (chitosan, Trichoderma harzianum T-22 and Bacillus subtilis QST713) applied alone or before Cucumber mosaic virus infection. Fruit production and antioxidant compounds were investigated by ultrahigh-performance liquid chromatography (UHPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: Compared to control fruit harvested from untreated and healthy plants, treatment with QST713 increased the fruit number. Furthermore, plant treatments with T22, QST713 and chitosan alone enhanced fruit carotenoids (lutein and ß-carotene), ascorbic acid and phenolic acids (caffeoyl glucoside and p-coumaroyl glucoside). In parallel, compared to fruit harvested from only CMV-infected plants, treatments with T22, QST713 and chitosan before CMV enhanced fruit ascorbic acid and flavonoids (quercetin 3-O-xylosyl-rutinoside and rutin). CONCLUSION: Antioxidant compounds of tomato fruit can increase with the application of the plant defence inducers, thus protecting both the consumer and plant health. © 2019 Society of Chemical Industry.

Investigation on side-product formation during the synthesis of a lactoferrin-derived lactam-bridged cyclic peptide.

Bovine lactoferrin C-lobe is able to prevent both influenza virus hemagglutination and cell infection. In particular, it was demonstrated that the fragment 418SKHSSLDCVLRP429 is a potent antiviral peptide. Therefore, we tried to increase the stability of this fragment through side-chain lactam cyclization of the peptide, S[KHSSLD]CVLRP (1). However, classic strategy involving solid-supported cyclization of the linear precursor, containing orthogonal allyl/alloc-based protection for the key amino and carboxyl residues, did not provide the desired cyclic peptide. Here, we report the identification of problematic stretches during the sequence assembly process and the optimization of the different parameters involved in the construction of 1. Results indicated a significant influence of ß-protecting group of both aspartic acid and adjacent cysteine residues on the formation of side products. Therefore, the identification of suitable ß-protecting groups of these residues allowed us to optimize the synthesis of designed lactam-bridged cyclic peptide.

Antioxidant Properties of Buffalo-Milk Dairy Products: A ß-Lg Peptide Released after Gastrointestinal Digestion of Buffalo Ricotta Cheese Reduces Oxidative Stress in Intestinal Epithelial Cells.

Redox signaling regulates different gastrointestinal (G.I.) epithelium functions. At the intestinal level, the loss of redox homeostasis in intestinal epithelial cells (IECs) is responsible for the pathogenesis and development of a wide diversity of G.I. disorders. Thus, the manipulation of oxidative stress in IECs could represent an important pharmacological target for different diseases. In this study, peptides released from in vitro gastro intestinal digestion of different buffalo-milk commercial dairy products were identified and evaluated for their bioactive properties. In particular, six G.I. digests of dairy products were tested in a model of oxidative stress for IECs. Among them, buffalo ricotta cheese was the most active and the presence of an abundant ß-lactoglobulin peptide (YVEELKPTPEGDL, f:60-72) was also revealed. The antioxidant potential of the identified peptide was also evaluated in a model of hydrogen peroxide (H2O2)-induced oxidative stress in the IEC-6 cell line. The peptide was able to reduce ROS release, while, on the other hand, it increased nuclear factor (erythroid-derived 2)-like 2 (Nrf2) activation and the expression of antioxidant cytoprotective factors, such as heme oxygenase 1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO1), and superoxide dismutase (SOD). These results indicate that buffalo ricotta cheese-isolated peptide could have potential in the treatment of some gastrointestinal disorders.

Fast Profiling of Natural Pigments in Different Spirulina (Arthrospira platensis) Dietary Supplements by DI-FT-ICR and Evaluation of their Antioxidant Potential by Pre-Column DPPH-UHPLC Assay.

Arthrospira platensis, better known as Spirulina, is one of the most important microalgae species. This cyanobacterium possesses a rich metabolite pattern, including high amounts of natural pigments. In this study, we applied a combined strategy based on Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) and Ultra High-Performance Liquid Chromatography (UHPLC) for the qualitative/quantitative characterization of Spirulina pigments in three different commercial dietary supplements. FT-ICR was employed to elucidate the qualitative profile of Spirulina pigments, in both direct infusion mode (DIMS) and coupled to UHPLC. DIMS showed to be a very fast (4 min) and accurate (mass accuracy ≤ 0.01 ppm) tool. 51 pigments were tentatively identified. The profile revealed different classes, such as carotenes, xanthophylls and chlorophylls. Moreover, the antioxidant evaluation of the major compounds was assessed by pre-column reaction with the DPPH radical followed by fast UHPLC-PDA separation, highlighting the contribution of single analytes to the antioxidant potential of the entire pigment fraction. ß-carotene, diadinoxanthin and diatoxanthin showed the highest scavenging activity. The method took 40 min per sample, comprising reaction. This strategy could represent a valid tool for the fast and comprehensive characterization of Spirulina pigments in dietary supplements, as well as in other microalgae-based products.

Development of an improved online comprehensive hydrophilic interaction chromatography × reversed-phase ultra-high-pressure liquid chromatography platform for complex multiclass polyphenolic sample analysis.

In this study, an improved online comprehensive two-dimensional liquid chromatography platform coupled to tandem mass spectrometry was developed for the analysis of complex polyphenolic samples. A narrowbore hydrophilic interaction chromatography column (150 × 2.0 mm, 3.0 µm, cross-linked diol) was employed in the first dimension, while a reversed-phase column based on monodisperse sub-2 µm fully porous particles (50 × 3.0 mm, 1.9 µm d.p.) with high surface area (410 m2 /g) was employed in the second dimension. The combination of a trapping column modulation interface with the high retentive fully porous monodisperse reversed-phase column in the second dimension resulted in higher peak capacity values (1146 versus 867), increased sensitivity, sharper and more symmetrical peaks in comparison with a conventional loop-based method, with the same analysis time (70 min). The system was challenged against a complex polyphenolic extract of a typical Italian apple cultivar, enabling the simultaneous separation of multiple polyphenolic classes, including oligomeric procyanidins, up to degree of polymerization of 10. Hyphenation with an ion trap time-of-flight mass spectrometer led to the tentative identification of 121 analytes, showing how this platform could be a powerful analytical tool for the accurate profiling of complex polyphenolic samples.

Flavonoid Composition of Tarocco (Citrus sinensis L. Osbeck) Clone "Lempso" and Fast Antioxidant Activity Screening by DPPH-UHPLC-PDA-IT-TOF.

INTRODUCTION: Clonal selection and hybridisation are valid strategies to obtain fruits with enhanced sensorial and nutraceutical properties. Within Citrus sinensis varieties, Tarocco clone "Lempso" is a typical product of the Calabria region (Italy) characterised by its red pulp. This is the first report concerning its accurate profiling. OBJECTIVE: To characterise in detail the flavonoid composition of Lempso clone and to compare its antioxidant potential with other Citrus varieties by a fast screening method. METHODOLOGY: Extracts were subjected to solid phase extraction and the qualitative/quantitative profile was elucidated through ultra-high performance liquid chromatography (UHPLC) coupled to photodiode array (PDA) and ion trap time-of-flight (IT-TOF) mass spectrometry detection, and compared to both Cleopatra mandarin (Citrus reticulata) and blood orange (Citrus sinensis (L.) Osbeck) Sanguinello varieties. The antioxidant activity was assessed by pre-column 2,2'-diphenyl-1-picrylhydrazyl (DPPH) reaction coupled to UHPLC-PDA. RESULTS: Lempso is characterised by flavonoids (17) and anthocyanins (8). Flavanones content (Hesperidin: 57.19 ± 0.49, Vicenin-2: 4.59 ± 0.03, Narirutin: 5.78 ± 0.13 mg/100 mL) was considerably higher than Cleopatra and Sanguinello varieties. The developed DPPH-UHPLC-PDA method provides information regarding the single contributions to antioxidant activity, highlighting how Ferulic acid, Quercetin and Cyanidin derivatives possess considerable radical scavenging activity (> 50%). The total antioxidant activity was also evaluated and compared with positive controls, showing higher scavenging activity than Cleopatra and Sanguinello (IC50 : 333.76 ± 10.81 µg/mL vs. 452.62 ± 10.81 and 568.39 ± 26.98 µg/mL, respectively). CONCLUSION: These data evidence the nutraceutical potential of Lempso variety, which could be an ingredient for functional beverages. Copyright © 2017 John Wiley & Sons, Ltd.

Bioavailable Citrus sinensis Extract: Polyphenolic Composition and Biological Activity.

Citrus plants contain large amounts of flavonoids with beneficial effects on human health. In the present study, the antioxidant and anti-inflammatory potential of bioavailable polyphenols from Citrus sinensis was evaluated in vitro and ex vivo, using the murine macrophages cell line J774A.1 and primary peritoneal macrophages. Following simulated gastro-intestinal digestion, the in vitro bioavailability of Citrus sinensis polyphenolic extract was assessed using the human cell line Caco-2 grown as monolayers on a transwell membrane. Data demonstrated a relative permeation of its compounds (8.3%). Thus, the antioxidant and anti-inflammatory effect of polyphenolic Citrus sinensis fraction (Cs) was compared to the bioavailable one (CsB). Results revealed that Citrus extract were able to reduce macrophages pro-inflammatory mediators, including nitric oxide, iNOS, COX-2 and different cytokines. Moreover, the effect of Citrus sinensis polyphenols was associated with antioxidant effects, such as a reduction of reactive oxygen species (ROS) and heme-oxygenase-1 (HO-1) increased expression. Our results provide evidence that the bioavailable polyphenolic constituents of the Citrussinensis extract accumulate prevalently at intestinal level and could reach systemic circulation exerting their effect. The bioavailable fraction showed a higher anti-inflammatory and antioxidant potential compared to the initial extract, thus highlighting its potential nutraceutical value.

Anti-inflammatory and antioxidant activity of polyphenolic extracts from Lactuca sativa (var. Maravilla de Verano) under different farming methods.

BACKGROUND: Besides their nutritional value, vegetables are a source of health-promoting compounds, such as polyphenols, and their content can be influenced by the particular farming method. In this study polyphenolic extracts from Lactuca sativa (var. Maravilla de verano) plants cultivated with different farming methods were chemically characterised and tested in vitro and ex vivo inflammation models. RESULTS: The tested extacts (250-2.5 µg mL(-1) ) were able to reduce both the inflammatory and oxidative stress in LPS-stimulated J774A.1 murine monocyte macrophage cells, by lowering the release of nitric oxide (NO) and reactive oxygen species (ROS) and promoting nuclear translocation of nuclear factor (erythroid-derived 2)-like 2; (Nrf2) and nuclear factor-κB (NF-κB). In this regard, quantitative profiles revealed different amounts of polyphenols, in particular quercetin levels were higher in plants under mineral fertilised treatment. Those extract showed an enhanced anti-inflammatory and antioxidant activity. CONCLUSION: Our data showed the anti-inflammatory and antioxidant potential of Maravilla de Verano polyphenolic extracts. The effect of farming methods on polyphenolic levels was highlighted. The higher reduction of inflammatory mediators release in extracts from plants cultivated under mineral fertilisation treatment was correlated to the higher amount of quercetin. These results can be useful for both nutraceutical or agronomic purposes. © 2016 Society of Chemical Industry.

Antitumor Mechanisms of Lycium barbarum Fruit: An Overview of In Vitro and In Vivo Potential.

Lycium barbarum, known as goji berry or wolfberry, is a fruit long associated with health benefits, showing a plethora of effects ranging from antioxidant, anticancer, anti-inflammatory, and immunomodulatory effects. Its potential is attributed to the significant presence of polysaccharides, glycopeptides, polyphenols, flavonoids, carotenoids, and their derivatives. These compounds effectively counteract the action of free radicals, positively influencing cellular balance and intracellular signaling, contributing to overall cell health and function acting on multiple molecular pathways. Several fractions extracted from goji berries demonstrate antitumor properties, particularly effective against breast cancer, without showing cytotoxic effects on normal human cells. Hence, the review explored the fundamental traits of bioactive elements in Lycium barbarum and their potential in cancer treatment and, specifically, breast cancer. It focused on elucidating wolfberry's influenced biochemical pathways, its synergism with anticancer drugs, and its potential to alleviate the side effects associated with existing cancer treatments.

Anticancer Therapies Based on Oxidative Damage: Lycium barbarum Inhibits the Proliferation of MCF-7 Cells by Activating Pyroptosis through Endoplasmic Reticulum Stress.

Lycium barbarum, commonly recognized as goji berry or wolfberry, is highly appreciated not only for its organoleptic and nutritional properties but also as an important source of bioactive compounds such as polysaccharides, carotenoids, phenolics, and various other non-nutritive compounds. These constituents give it a multitude of health benefits, including antioxidant, anti-inflammatory, and anticancer properties. However, the precise biochemical mechanisms responsible for its anticancer effects remain unclear, and the comprehensive composition of goji berry extracts is often insufficiently explored. This study aimed to investigate the biochemical pathways modulated in breast cancer cells by an ethanolic extract of Lycium barbarum fruit (LBE). Following metabolomic profiling using UHPLC-HRMS/MS, we assessed the antitumoral properties of LBE on different breast cancer cell lines. This investigation revealed that LBE exhibited cytotoxic effects, inducing a pro-oxidant effect that triggered pyroptosis activation through endoplasmic reticulum (ER) stress and subsequent activation of the P-IRE1α/XBP1/NLRP3 axis in MCF-7 cells. In addition, LBE did not display cytotoxicity toward healthy human cells but demonstrated antioxidant properties by neutralizing ROS generated by doxorubicin. These findings underscore the potential of LBE as a highly promising natural extract in cancer therapy.

Peptidomimetics as potent dual SARS-CoV-2 cathepsin-L and main protease inhibitors: In silico design, synthesis and pharmacological characterization.

In this paper we present the design, synthesis, and biological evaluation of a new series of peptidomimetics acting as potent anti-SARS-CoV-2 agents. Starting from our previously described Main Protease (MPro) and Papain Like Protease (PLPro) dual inhibitor, CV11, here we disclose its high inhibitory activity against cathepsin L (CTSL) (IC50 = 19.80 ± 4.44 nM), an emerging target in SARS-CoV-2 infection machinery. An in silico design, inspired by the structure of CV11, led to the development of a library of peptidomimetics showing interesting activities against CTSL and Mpro, allowing us to trace the chemical requirements for the binding to both enzymes. The screening in Vero cells infected with 5 different SARS-CoV-2 variants of concerns, highlighted sub-micromolar activities for most of the synthesized compounds (13, 15, 16, 17 and 31) in agreement with the enzymatic inhibition assays results. The compounds showed lack of activity against several different RNA viruses except for the 229E and OC43 human coronavirus strains, also characterized by a cathepsin-L dependent release into the host cells. The most promising derivatives were also evaluated for their chemical and metabolic in-vitro stability, with derivatives 15 and 17 showing a suitable profile for further preclinical characterization.

Traceability and authentication in agri-food production: A multivariate approach to the characterization ofthe Italian food excellence elephant garlic (Allium ampeloprasum L.), a vasoactive nutraceutical.

A research platform for food authentication was set up by combining stable isotope ratio analysis, metabolomics by gas and liquid mass-spectrometry and NMR investigations, chemometric analyses for food excellences. This multi-analytical approach was tested on samples of elephant garlic (Allium ampeloprasum L.), a species belonging to the same genus of common garlic (Allium ampeloprasum L.), mainly produced in southern Tuscany-(Allium ampeloprasum). The isotopic composition allowed the product to be geographically characterized. Flavonoids, like (+)-catechin, cinnamic acids, quercetin glycosides were identified. The samples showed also a significant amount of dipeptides, sulphur-containing metabolites and glutathione, the latter of which could be considered a molecular marker of the analyzed elephant garlic. For nutraceutical profiling to reach quality labels, extracts were investigated in specific biological assays, displaying interesting vasorelaxant properties in rat aorta by mediating nitric oxide release from the endothelium and exhibited positive inotropic and negative chronotropic effects in rat perfused heart.

In Silico Assisted Identification, Synthesis, and In Vitro Pharmacological Characterization of Potent and Selective Blockers of the Epilepsy-Associated KCNT1 Channel.

Gain-of-function (GoF) variants in KCNT1 channels cause severe, drug-resistant forms of epilepsy. Quinidine is a known KCNT1 blocker, but its clinical use is limited due to severe drawbacks. To identify novel KCNT1 blockers, a homology model of human KCNT1 was built and used to screen an in-house library of compounds. Among the 20 molecules selected, five (CPK4, 13, 16, 18, and 20) showed strong KCNT1-blocking ability in an in vitro fluorescence-based assay. Patch-clamp experiments confirmed a higher KCNT1-blocking potency of these compounds when compared to quinidine, and their selectivity for KCNT1 over hERG and Kv7.2 channels. Among identified molecules, CPK20 displayed the highest metabolic stability; this compound also blocked KCNT2 currents, although with a lower potency, and counteracted GoF effects prompted by 2 recurrent epilepsy-causing KCNT1 variants (G288S and A934T). The present results provide solid rational basis for future design of novel compounds to counteract KCNT1-related neurological disorders.

Novel pyrrole based CB2 agonists: New insights on CB2 receptor role in regulating neurotransmitters' tone.

The cannabinoid system is one of the most investigated neuromodulatory systems because of its involvement in multiple pathologies such as cancer, inflammation, and psychiatric diseases. Recently, the CB2 receptor has gained increased attention considering its crucial role in modulating neuroinflammation in several pathological conditions like neurodegenerative diseases. Here we describe the rational design of pyrrole-based analogues, which led to a potent and pharmacokinetically suitable CB2 full agonist particularly effective in improving cognitive functions in a scopolamine-induced amnesia murine model. Therefore, we extended our study by investigating the interconnection between CB2 activation and neurotransmission in this experimental paradigm. To this purpose, we performed a MALDI imaging analysis on mice brains, observing that the administration of our lead compound was able to revert the effect of scopolamine on different neurotransmitter tones, such as acetylcholine, serotonin, and GABA, shedding light on important networks not fully explored, so far.

Ultra high performance liquid chromatography with ion-trap TOF-MS for the fast characterization of flavonoids in Citrus bergamia juice.

We have developed a fast ultra HPLC with ion-trap TOF-MS method for the analysis of flavonoids in Citrus bergamia juice. With respect to the typical methods for the analysis of these matrices based on conventional HPLC techniques, a tenfold faster separation was attained. The use of a core-shell particle column ensured high resolution within the fast analysis time of only 5 min. Unambiguous determination of flavonoid identity was obtained by the employment of a hybrid ion-trap TOF mass spectrometer with high mass accuracy (average error 1.69 ppm). The system showed good retention time and peak area repeatability, with maximum RSD% values of 0.36 and 3.86, respectively, as well as good linearity (R(2) ≥ 0.99). Our results show that ultra HPLC can be a useful tool for ultra fast qualitative/quantitative analysis of flavonoid compounds in citrus fruit juices.

Potential Role of Natural Antioxidant Products in Oncological Diseases.

Nutrition has a significant effect and a crucial role in disease prevention. Low consumption of fruit and vegetables and a sedentary lifestyle are closely related with the onset and development of many types of cancer. Recently, nutraceuticals have gained much attention in cancer research due to their pleiotropic effects and relatively non-toxic behavior. In fact, although in the past there have been conflicting results on the role of some antioxidant compounds as allies against cancer, numerous recent clinical studies highlight the efficacy of dietary phytochemicals in the prevention and treatment of cancer. However, further investigation is necessary to gain a deeper understanding of the potential anticancer capacities of dietary phytochemicals as well as the mechanisms of their action. Therefore, this review examined the current literature on the key properties of the bioactive components present in the diet, such as carotenoids, polyphenols, and antioxidant compounds, as well as their use in cancer therapy. The review focused on potential chemopreventive properties, evaluating their synergistic effects with anticancer drugs and, consequently, the side effects associated with current cancer treatments.

Optimization of microwave-assisted extraction of antioxidant compounds from spring onion leaves using Box-Behnken design.

Many studies have explored the extraction of bioactive compounds from different onion solid wastes, such as bulb, skin, and peel. However, onion leaves have received limited attention despite their potential as a valuable source of nutraceutical compounds. This study aimed to valorise, for the first time, the agricultural waste in the form of spring onion leaves (CN, Cipollotto Nocerino) to obtain antioxidant-rich polyphenolic extracts. A Box-Behnken design (BBD) was used to assess the impact of microwave-assisted extraction (MAE) variables (temperature, time, extraction volume, and ethanol concentration) on total polyphenol content (TPC) measured by Folin-Ciocalteu method and the antioxidant power determined by FRAP assay. Response surface methodology (RSM) was applied, and regression equations, analysis of variance, and 3D response curves were developed. Our results highlighted that the TPC values range from 0.76 to 1.43 mg GAE g-1 dw, while the FRAP values range from 8.25 to 14.80 mmol Fe(II)E g-1 dw. The optimal extraction conditions predicted by the model were 60 °C, 22 min, ethanol concentration 51% (v/v), and solvent volume 11 mL. These conditions resulted in TPC and FRAP values of 1.35 mg GAE g-1 dw and 14.02 mmol Fe(II)E g-1 dw, respectively. Furthermore, the extract obtained under optimized conditions was characterized by UHPLC-ESI-Orbitrap-MS analysis. LC/MS-MS platform allowed us to tentatively identify various compounds belonging to the class of flavonoids, saponins, fatty acids, and lipids. Finally, the ability of CN optimal extract to inhibit the intracellular reactive oxygen species (ROS) release in a hepatocarcinoma cell line using an H2O2-induced oxidative stress model, was evaluated. The results highlighted the potential of CN extract as a valuable source of polyphenols with significant antioxidant properties, suitable for various applications in the food and pharmaceutical industries.