Federica Narra

Dr. Federica Narra

Department of Agricolture, Food and Environment, University of Pisa, Pisa, Tuscany, Italy
orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 August 2024 in Comprehensive Reviews in Food Science and Food Safety
Verified
Journal Article
Open access
Federica NarraFederica Narra
Federica Narra
EPEugenia Piragine
Eugenia Piragine
GBGiada Benedetti
Giada Benedetti
Costanza CeccantiCostanza Ceccanti
Costanza Ceccanti
MFMarta Florio
Marta Florio
LGLucia Guidi
Lucia Guidi
Bioactive compounds in fruit and vegetables have a positive impact on human health by reducing oxidative stress, inflammation, and the risk of chronic diseases such as cancer, cardiovascular (CV) diseases, and metabolic disorders. However, some fruit and vegetables must be heated before consumption and thermal processes can modify the amount of nutraceuticals, that is, polyphenols, carotenoids, glucosinolates, and ascorbic acid, that can increase or decrease in relation to different factors such as type of processing, temperature, and time but also the plant part (e.g., flower, leaf, tuber, and root) utilized as food. Another important aspect is related to the bioaccessibility and bioavailability of nutraceuticals. Indeed, the key stage of nutraceutical bioefficiency is oral bioavailability, which involves the release of nutraceuticals from fruit and vegetables in gastrointestinal fluids, the solubilization of nutraceuticals and their interaction with other components of gastrointestinal fluids, the absorption of nutraceuticals by the epithelial layer, and the chemical and biochemical transformations into epithelial cells. Several studies have shown that thermal processing can enhance the absorption of nutraceuticals from fruit and vegetable. Once absorbed, they reach the blood vessels and promote multiple biological effects (e.g., antioxidant, anti‐inflammatory, antihypertensive, vasoprotective, and cardioprotective). In this review, we described the impact of different thermal processes (such as boiling, steaming and superheated steaming, blanching, and microwaving) on the retention/degradation of bioactive compounds and their health‐promoting effects after the intake. We then summarized the impact of heating on the absorption of nutraceuticals and the biological effects promoted by natural compounds in the CV system to provide a comprehensive overview of the potential impact of thermal processing on the CV benefits of fruit and vegetables.

19 August 2025 in Foods
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Journal Article
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Federica NarraFederica Narra
Federica Narra
GGGiulia Galgani
Giulia Galgani
Cassidy Bo HarrisCassidy Bo Harris
Cassidy Bo Harris
Diego A. Moreno-FernandezDiego A. Moreno-Fernandez
Diego A. Moreno-Fernandez
VNVanesa Núñez-Gómez
Vanesa Núñez-Gómez
Glucosinolates (GSLs) and their breakdown products, isothiocyanates (ITCs), are bioactive compounds with anti-inflammatory, antioxidant, and anticancer properties, mediated through key pathways such as Nrf2, NF-κB, and epigenetic regulation. However, their limited and variable bioavailability remains a key challenge. This review summarises the current clinical evidence on GSLs and ITCs, with a focus on their health effects and metabolic fate in humans. Recent findings on enzymatic and microbial metabolism are discussed, along with results from interventions involving whole vegetables, sprouts, and extracts. Although promising effects on blood pressure, lipid profiles, and glycaemic control have been observed, clinical studies are often limited by small sample sizes, study heterogeneity, and high inter-individual variability, particularly related to gut microbiota and host metabolic phenotype. Challenges like inconsistent biomarkers, formulation variability, and tolerability issues complicate data interpretation. To realise their full potential, larger, standardised, microbiome-informed trials with validated biomarkers and optimised delivery are needed to clarify host–compound–microbiome interactions and support evidence-based disease prevention strategies.

17 February 2025 in Food & Function
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FRANCESCA GIROTTOFRANCESCA GIROTTO
FRANCESCA GIROTTO
Costanza CeccantiCostanza Ceccanti
Costanza Ceccanti
Federica NarraFederica Narra
Federica Narra
LPLaura Piazza
Laura Piazza
In a context where whey proteins currently dominate the protein sports beverage sector and pea proteins are usually commercialized as protein sources, this study proposes using sunflower press-cake, which contains approximately 44% protein, as an alternative and sustainable protein source. After the extraction from the press-cake, sunflower proteins were dispersed in an aqueous medium with varying xanthan gum concentrations (0.2%, 0.4% and 0.6% w/v) to simulate protein-rich sports beverages. Their performance was compared to that of whey and pea proteins, each at a 10% concentration. To enhance protein dispersibility and align with the trends of alkaline beverages, a K–P buffer at pH 9 was used as the dispersion medium, and 0.2% caffeine was included for cognitive benefits. Pasteurized dispersions were tested for rheological behavior and physical stability at 4 °C. Sunflower proteins, with a total polyphenolic content (TPC) of 35.2 mgGAE gDB −1, outperformed whey (0.8 mgGAE gDB −1) and pea (2.8 mgGAE gDB −1) proteins. Sunflower dispersions exhibited a significantly lower volatile profile than those enriched with pea or whey proteins, reducing the need for odor-masking agents. Additionally, sunflower dispersions had a lower flow index than whey or pea dispersions, indicating easier processing. Despite the promising flow behaviour and optimal physical stability (stability index < 1.0), in vitro bioaccessibility analysis revealed a similar percentage of protein bioaccessibility between pea and whey dispersions, while sunflower ones had the lowest percentage. TPC bioaccessibility followed a similar trend. These findings highlight the feasibility of incorporating sunflower proteins into sports beverages, broadening options for formulators and promoting sustainability by repurposing agricultural by-products and adopting plant-based proteins.

31 May 2023 in Journal of the Science of Food and Agriculture
Verified
Journal Article
Open access
Federica NarraFederica Narra
Federica Narra
ACAntonella Castagna
Antonella Castagna
GPGiacomo Palai
Giacomo Palai
JHJaroslav Havlík
Jaroslav Havlík
ABAnna Mascellani Bergo
Anna Mascellani Bergo
MSMarco Santin
Marco Santin
BACKGROUND: The ultraviolet‐B (UV‐B) radiation can alter grape metabolism during berry development, but little is known on the effect of postharvest UV‐B exposure. In this study, we evaluated the effect of postharvest UV‐B exposure on berry primary and secondary metabolites in four grapevine varieties (Aleatico, Moscato bianco, Sangiovese, and Vermentino) in order to evaluate the possibility to increase the grape quality and its nutraceutical properties.RESULTS: The treatment did not significantly affect the berry primary metabolism in terms of organic acids, carbohydrates, and amino acids profile, regardless of the variety. UV‐B exposure reduced the total anthocyanin content, particularly the tri‐substituted and di‐substituted forms in Aleatico and Sangiovese, respectively. An overall negative effect of UV‐B irradiation on the flavonols profile of Aleatico, Moscato bianco, and Vermentino berries was found, whereas it enhanced the quercetin, myricetin and kaempferol concentration in Sangiovese. The free fraction of berry volatile organic compounds increased in UV‐B‐treated Aleatico and Moscato bianco berries, especially C13‐norisoprenoids and volatile phenols, as well as key monoterpenes, such as the linalool derivatives. However, higher concentrations of glycosylated monoterpenes and C13‐norisoprenoids were measured in Sangiovese and Vermentino berries treated with UV‐B.CONCLUSION: This study provides new insights on the effect of postharvest UV‐B radiation on berry secondary metabolism, highlighting a different modulation between varieties and suggesting the potential use of this technique to increase some nutraceutical and quality characteristics of grape berry. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

19 November 2024 in Foods
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Federica NarraFederica Narra
Federica Narra
Federico BriganteFederico Brigante
Federico Brigante
EPEUGENIA PIRAGINE
EUGENIA PIRAGINE
Pavel SolovyevPavel Solovyev
Pavel Solovyev
GBGiada Benedetti
Giada Benedetti
Lucia GuidiLucia Guidi
Lucia Guidi
The present study investigated the changes in the organoleptic characteristics, nutraceuticals, and antioxidant activity of tomato fruits subjected to different thermal processes: tomato sauce (80 °C for 30 min), blanching treatment (100 °C for 10 s), and the superheated steam method (SHS; 100 °C for 7 min) compared with fresh tomato fruit. Even though SHS negatively modified the color of the product (L* −7% than fresh tomatoes), it was the only technology able to increase the antioxidant activity compared with fresh tomatoes (e.g., +40.3% in ABTS assay), whilst lycopene and ascorbic acid contents reported similar values to fresh tomatoes. Regarding lycopene, only 5Z-lycopene (with a higher bioavailability than (all-E)-isomers) was found in all samples, and SHS maintained the same level observed in fresh tomato fruit. Furthermore, SHS technology preserved the antioxidant effects of fresh tomato extract even in human endothelial cells. This result confirmed those obtained in previous “cell-free” assays and demonstrated that SHS treatment significantly maintains the biological properties of tomato fruit in preventing oxidative stress. However, heat-treated tomato extracts did not show the same effects as fresh tomato extract against noradrenaline-induced vasoconstriction in isolated rat aortic rings. This study demonstrates that the use of SHS technology can be considered an innovative and sustainable thermal process (in terms of maintaining the nutraceutical quality) for tomato fruits, thus paving the way for future investigations on the effects of fresh and heat-treated tomatoes after intestinal absorption in vitro and in vivo.