Alfonso Narváez

Dr. Alfonso Narváez

University of Naples Federico II, Naples, Campania, Italy
orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

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

Representative Publications

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8 October 2019 in Molecules
Verified
Journal Article
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Luigi CastaldoLuigi Castaldo
Luigi Castaldo
ANAlfonso Narváez
Alfonso Narváez
Luana IzzoLuana Izzo
Luana Izzo
GGGiulia Graziani
Giulia Graziani
AGAnna Gaspari
Anna Gaspari
Alberto RitieniAlberto Ritieni
Alberto Ritieni
Wine is a popular alcoholic beverage that has been consumed for hundreds of years. Benefits from moderate alcohol consumption have been widely supported by the scientific literature and, in this line, red wine intake has been related to a lesser risk for coronary heart disease (CHD). Experimental studies and meta-analyses have mainly attributed this outcome to the presence in red wine of a great variety of polyphenolic compounds such as resveratrol, catechin, epicatechin, quercetin, and anthocyanin. Resveratrol is considered the most effective wine compound with respect to the prevention of CHD because of its antioxidant properties. The mechanisms responsible for its putative cardioprotective effects would include changes in lipid profiles, reduction of insulin resistance, and decrease in oxidative stress of low-density lipoprotein cholesterol (LDL-C). The aim of this review is to summarize the accumulated evidence correlating moderate red wine consumption with prevention of CHD by focusing on the different mechanisms underlying this relationship. Furthermore, the chemistry of wine as well as chemical factors that influence the composition of the bioactive components of red wine are also discussed.

31 January 2020 in Molecules
Verified
Journal Article
Open access
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Luana IzzoLuana Izzo
Luana Izzo
Luigi CastaldoLuigi Castaldo
Luigi Castaldo
ANAlfonso Narváez
Alfonso Narváez
GGGiulia Graziani
Giulia Graziani
AGAnna Gaspari
Anna Gaspari
Alberto RitieniAlberto Ritieni
Alberto Ritieni
Industrial hemp (Cannabis sativa L. Family Cannabaceae) contains a vast number of bioactive relevant compounds, namely polyphenols including flavonoids, phenolic acids, phenol amides, and lignanamides, well known for their therapeutic properties. Nowadays, many polyphenols-containing products made of herbal extracts are marketed, claiming to exert health-promoting effects. In this context, industrial hemp inflorescence may represent an innovative source of bioactive compounds to be used in nutraceutical formulations. The aim of this work was to provide a comprehensive analysis of the polyphenolic fraction contained in polar extracts of four different commercial cultivars (Kompoti, Tiborszallasi, Antal, and Carmagnola Cs) of hemp inflorescences through spectrophotometric (TPC, DPPH tests) and spectrometry measurement (UHPLC-Q-Orbitrap HRMS). Results highlighted a high content of cannflavin A and B in inflorescence analyzed samples, which appear to be cannabis-specific, with a mean value of 61.8 and 84.5 mg/kg, meaning a ten-to-hundred times increase compared to other parts of the plant. Among flavonols, quercetin-3-glucoside reached up to 285.9 mg/kg in the Carmagnola CS cultivar. Catechin and epicatechin were the most representative flavanols, with a mean concentration of 53.3 and 66.2 mg/kg, respectively, for all cultivars. Total polyphenolic content in inflorescence samples was quantified in the range of 10.51 to 52.58 mg GAE/g and free radical-scavenging included in the range from 27.5 to 77.6 mmol trolox/kg. Therefore, C. sativa inflorescence could be considered as a potential novel source of polyphenols intended for nutraceutical formulations.

14 August 2020 in Molecules
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Journal Article
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Luana IzzoLuana Izzo
Luana Izzo
Severina PacificoSeverina Pacifico
Severina Pacifico
Simona PiccolellaSimona Piccolella
Simona Piccolella
Luigi CastaldoLuigi Castaldo
Luigi Castaldo
ANAlfonso Narváez
Alfonso Narváez
Alberto RitieniAlberto Ritieni
Alberto Ritieni
Although hemp seed (HS) oil is characterized by more than 80% polyunsaturated fatty acids (PUFAs), a very high ω-6-to-ω-3 ratio is not a popular commodity. The aim of this work was to provide useful data about the bioactive components and cannabidiolic acid content in thirteen different commercial hemp seed oils. The investigated HS oils showed a good ω-6/ω-3 ratio, ranging from 1.71 to 2.27, massively differed in their chlorophylls (0.041–2.64 µg/g) and carotenoids contents (0.29–1.73 µg/g), as well as in total phenols (22.1–160.8 mg Gallic Acid Equivalents (GAE)/g) and tocopherols (3.47–13.25 mg/100 g). Since the high content of PUFAs in HS oils, photo-oxidative stability was investigated by determining the Thiobarbituric Acid Reactive Substances (TBARS) assay and extinction coefficient K232 and K270 after the photo-oxidative test. The percentage of increase in K232 and K270 ranged from 1.2 to 8.5% and from 3.7 to 26.0%, respectively, indicating good oxidative stability, but TBARS showed a 1.5- to 2.5-fold increase in oxidative behavior when compared to the initial values. Therefore, the diversity in bioactive compounds in HS oils, and their high nutritional value, suggest the need for a disciplinary booklet that well defines agronomic and post-harvest management conditions for achieving a good food objective.

2 May 2020 in Molecules
Verified
Journal Article
Open access
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Luigi CastaldoLuigi Castaldo
Luigi Castaldo
ANAlfonso Narváez
Alfonso Narváez
Luana IzzoLuana Izzo
Luana Izzo
GGGiulia Graziani
Giulia Graziani
Alberto RitieniAlberto Ritieni
Alberto Ritieni
Coffee silverskin (CS), the main by-product in the coffee industry, contains a vast number of human health-related compounds, which may justify its exploitation as a functional food ingredient. This study aimed to provide a comprehensive analysis of the polyphenolic and alkaloid profile through UHPLC-Q-Orbitrap HRMS analysis. The bioaccessibility of total phenolic compounds and changes in the antioxidant activity during an in vitro gastrointestinal digestion were also evaluated through spectrophotometric tests (TPC by Folin-Ciocalteu, ABTS, DPPH, and FRAP), to elucidate their efficacy for future applications in the nutraceutical industry. Caffeoylquinic and feruloylquinic acids were the most representative polyphenols, with a mean concentration of 5.93 and 4.25 mg/g, respectively. Results showed a high content of caffeine in the analyzed CS extracts, with a mean value of 31.2 mg/g, meaning a two-fold increase when compared to coffee brews. Our findings highlighted that both the bioaccessibility and antioxidant activity of CS polyphenols significantly increased in each in vitro gastrointestinal digestion stage. In addition, the colon stage might constitute the main biological site of action of these antioxidant compounds. These results suggest that in vivo, the dietary polyphenols from CS might be metabolized by human colonic microflora, generating metabolites with a greater antioxidant activity, increasing their well-known beneficial effects.

5 December 2021 in Nutrients
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Luigi CastaldoLuigi Castaldo
Luigi Castaldo
MTMarianna Toriello
Marianna Toriello
RSRaffaele Sessa
Raffaele Sessa
Luana IzzoLuana Izzo
Luana Izzo
SLSonia Lombardi
Sonia Lombardi
MGMichela Grosso
Michela Grosso
Coffee contains human health-related molecules, namely polyphenols that possess a wide range of pharmacological functions, and their intake is associated with reduced colon cancer risk. This study aimed to assess the changes in the anti-inflammatory and antioxidant activity of coffee after simulated gastrointestinal digestion. The evaluation of intracellular reactive oxygen species (ROS) levels in the HT-29 human colon cancer cell line and three in vitro spectrophotometric assays were performed to determine the antioxidant activity of the samples. Characterization of coffee composition was also assessed through a Q-Orbitrap high-resolution mass spectrometry analysis. The results highlighted that the levels of polyphenols in the digested coffee brews were higher than those of the non-digested ones. All assayed samples decreased the levels of intracellular ROS when compared to untreated cells, while digested coffee samples exhibited higher antioxidant capacity and total phenolic content than not-digested coffee samples. Digested coffee samples showed a higher reduction in interleukin-6 levels than the not-digested samples in lipopolysaccharide-stimulated HT-29 cells treated for 48 h and fewer cytotoxic effects in the MTT assay. Overall, our findings suggest that coffee may exert antioxidant and anti-inflammatory properties, and the digestion process may be able to release compounds with higher bioactivity.

12 February 2020 in Toxins
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Journal Article
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ANAlfonso Narváez
Alfonso Narváez
YRYelko Rodríguez-Carrasco
Yelko Rodríguez-Carrasco
Luigi CastaldoLuigi Castaldo
Luigi Castaldo
Luana IzzoLuana Izzo
Luana Izzo
Alberto RitieniAlberto Ritieni
Alberto Ritieni
Cannabidiol (CBD) food supplements made of Cannabis sativa L. extracts have quickly become popular products due to their health-promoting effects. However, potential contaminants, such as mycotoxins and pesticides, can be coextracted during the manufacturing process and placed into the final product. Accordingly, a novel methodology using ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) was developed to quantify 16 mycotoxins produced by major C. sativa fungi, followed by a post-target screening of 283 pesticides based on a comprehensive spectral library. The validated procedure was applied to ten CBD-based products. Up to six different Fusarium mycotoxins were found in seven samples, the most prevalent being zearalenone (60%) and enniatin B1 (30%), both found at a maximum level of 11.6 ng/g. Co-occurrence was observed in four samples, including one with enniatin B1, enniatin A and enniatin A1. On the other hand, 46 different pesticides were detected after retrospective analysis. Ethoxyquin (50%), piperonyl butoxide (40%), simazine (30%) and cyanazine (30%) were the major residues found. These results highlight the necessity of monitoring contaminants in food supplements in order to ensure a safe consumption, even more considering the increase trend in their use. Furthermore, the developed procedure is proposed as a powerful analytical tool to evaluate the potential mycotoxin profile of these particular products.