100 research outputs found
Reaction with ROO• and HOO• Radicals of Honokiol-Related Neolignan Antioxidants
No full textHonokiol is a natural bisphenol neolignan present in the bark of Magnolia officinalis, whose extracts have been employed in oriental medicine to treat several disorders, showing a variety of biological properties, including antitumor activity, potentially related to radical scavenging. Six bisphenol neolignans with structural motifs related to the natural bioactive honokiol were synthesized. Their chain-breaking antioxidant activity was evaluated in the presence of peroxyl (ROO•) and hydroperoxyl (HOO•) radicals by both experimental and computational methods. Depending on the number and position of the hydroxyl and alkyl groups present on the molecules, these derivatives are more or less effective than the reference natural compound. The rate constant of the reaction with ROO• radicals for compound 7 is two orders of magnitude greater than that of honokiol. Moreover, for compounds displaying quinonic oxidized forms, we demonstrate that the addition of 1,4 cyclohexadiene, able to generate HOO• radicals, restores their antioxidant activity, because of the reducing capability of the HOO• radicals. The antioxidant activity of the oxidized compounds in combination with 1,4-cyclohexadiene is, in some cases, greater than that found for the starting compounds towards the peroxyl radicals. This synergy can be applied to maximize the performances of these new bisphenol neolignans
Spaghetti Enriched with Inulin: Effect of Polymerization Degree on Quality Traits and α-Amylase Inhibition
No full textInulin is considered a dietary fiber and represents a noteworthy ingredient for food biofortification due to its health effects and its neutral taste. The aim of the work was the evaluation of the quality of pasta produced using whole-meal flours of two ancient Sicilian landraces (Senatore Cappelli-CAP and Timilia—TIM) fortified with two types of inulin (long-chain topinambur inulin IT and low-chain chicory inulin IC), at two different levels of substitution (2 and 4%) to evaluate its possible effect on α-amylase inhibition. The color indices L* and a* were mainly influenced by cultivars, while IT improved the sensory attributes, mainly the elasticity sensation, and influenced less the other sensory attributes: adhesiveness, color, odor, taste, and Over Quality Score for both landraces. The cooking quality was linked mainly to the landrace used, due to the very different gluten matrix of CAP and TIM. IC and IT showed promising α-Amy inhibitory activity with comparable IC50 values of 0.45 ± 0.04 and 0.50 ± 0.06 mg/mL. The enrichment of spaghetti with inulin with an inhibitory effect on α-amylase determined the hypoglycemic properties of pasta, thus lowering the corresponding IC50 value
Dell'Ospitalità. L'essere per l'inizio di Nunzio Incardona
No full textThe author explores the work of Nunzio Incardona using the Derridean category of hospitality. The hermeneutic gain is an unprecedented reading of the beginning of philosophy that Incardona takes from Hegel
Biological effects of polyphenol-rich extract and fractions from an oenological oak-derived tannin on in vitro swine sperm capacitation and fertilizing ability
No full textAlthough excessive ROS levels induce sperm damage, sperm capacitation is an oxidative event that requires low amounts of ROS. As the antioxidant activity of the ethanol extract (TRE) of a commercial oenological tannin (Quercus robur toasted oak wood, Tan'Activ R®) and its four fractions (FA, FB, FC, FD) has been recently reported, the present study was set up to investigate the biological effects of TRE and its fractions in an in vitro model of sperm capacitation and fertilization. Boar sperm capacitation or gamete coincubation were performed in presence of TRE or its fractions (0, 1, 10, 100 Î1⁄4g/ml). TRE at the concentration of 10 Î1⁄4g/ml (TRE10) stimulated sperm capacitation, as it increased (p <.001) the percentage of spermatozoa with tyrosine-phosphorylated protein positivity in the tail principal piece (B pattern) (67.0 ± 10.6 vs. 48.6 ± 9.0, mean ± SD for TRE10 vs. Ctr respectively). Moreover T10 significantly (p <.001) increased oocyte fertilization rate (91.9 ± 4.0 vs. 69.0 ± 14.8, TRE10 vs. Ctr respectively). An opposite effect of TRE at the concentration of 100 Î1⁄4g/ml (TRE100) on both sperm capacitation (B pattern cell percentage 33.3 ± 29.2) and fertilizing ability (fertilization rate 4.9 ± 8.3), associated with a higher sperm viability (66.9 ± 9.3 vs. 35.4 ± 10.8, TRE100 vs. Ctr respectively) (p <.001), was recorded. The potency of the TRE fractions seems to be highest in FB followed by FC, faint in FD and nearly absent in FA. Our results show that TRE and its fractions, in a different extent, exert a powerful biological effect in finely modulating capacitation and sperm fertilizing ability
Proteasome as a new target for bio-inspired benzo[k,l]xanthene lignans
No full textMass spectrometry-based chemical proteomics is a powerful tool in the target discovery of small molecules. Here we present the application of this approach to define the target profile of bio-inspired synthetic benzo[k,l]xanthene lignans, endowed with interesting biological properties. Proteasome has been identified as a new main interactor for this class of compounds. A combination of molecular docking and in vitro and in cell fluorescence assays gave insights on the molecular mechanism of interaction, highlighting the the attitude of these lignans to inhibit the proteasome
Il Nilo e Mosè: dalla Vita di Mosè di Filone alle Etiopiche di Eliodoro
No full textThe aim of this paper is drawing attention to a passage of the Ethiopian Stories by Heliodorus of Emesa (9,9,3) on the divinization of the Nile borrowed from Life of Moses (2,195) by Philo of Alexandria. This textual relationship, well known to Philo’s scholars, has so far not been considered instead by most Heliodorus’ scholars. Other possible intertextual references (lexical parallels, stylisations and analogies), noticed in this paper, point to the work by Philon as deliberately exploited inspiration for some passages of Heliodorus’ novel. All this is of greater importance for the Ethiopian novel and his author
Appunti sulla tradizione manoscritta e la ricezione di Aristeneto
No full textThe purpose of this paper is to reconsider some features of Aristaenetus’ codex unicus Vindob. Phil. gr. 310 (such as the inscriptio, the readers and owners, the authorship of some medieval epigrams) and to provide new data about the manuscript tradition and reception of this author. In § 1 and § 2 I deal with medieval (Nicholas of Otranto, Palaganus) and humanistic (Janus Lascaris) readers and owners of this manuscript and with the inscriptio on the first leaf; in § 3 and § 4 I draw attention to a new Aristaenetus’ manuscript (written in the XVIIth century by the scholar Leone Allacci) and an hitherto unpublished Italian version made in 1701 by Girolamo Baruffaldi
Tecnica, estetica e processi comunicativi nel dibattito sulle “due culture”
No full textGli anni Cinquanta e Sessanta furono contrassegnati dal vertiginoso incremento di alcuni settori industriali (chimica, elettrodomestici, automobile, telecomunicazioni) e dalla diffusione della cultura di massa. Questo articolo ricostruisce il dibattito "due culture" in Italia focalizzandosi sull'impatto dello sviluppo della cibernetica e dell'informatizzazione sull'arte, la letteratura e i mass media.This article offers an historical reconstruction of the “two cultures” debate in Italy, focusing on the impact on art, literature and mass media of the technical evolution from mechanization to direct interaction with computing electronic devices dur- ing the 1960s. The concept of interaction in the Information science functioned beyond a purely technological paradigm, as showed by Umberto Eco in Opera Aperta (1962) and Apocalittici ed integrati (1964), emphasizing on openness and entropy in the poetics of con- temporary art, and the dissolution of borders between artistic experimentation, mass media and quotidian life. In his influential lecture Cibernetica e fantasmi (1967) Italo Calvino argued that Artificial intelligence provided a new model of dynamic transdisciplinary exchange for the investigation of rules and patterns embedded in writing processes, exploring the possibility of a «literary automaton», capable of replacing the author
Synthesis of natural-derived polyphenols as potential anticancer agents
No full textExtracts from plants or other organisms have been used for thousands of years as medicines and today a multitude of researchers continue to be inspired by the astonishing structural variety of natural products to identify potential lead compounds for drug discovery. In the simplest of terms, a natural product is a small molecule (generally with a molecular weight below 3000 Da) that is produced by a biological source; often the term is considered as synonymous for secondary metabolite and natural products research focuses on the biosynthesis and the study of chemical properties and biological functions of secondary metabolites. These are organic compounds not ubiquitous in all organisms, and represent an expression of the individuality of the species; secondary metabolites do not exert primary biological functions directly involved in the normal growth, development or reproduction of an organism but they may serve as chemical defense, intra- or interspecies communication, sexual attraction and to other purposes conferring an advantage to the organism producing them. The main families of secondary metabolites include isoprenoids, polyketides, alkaloids, non ribosomial peptides and polyphenols, these latter directly derived from shikimate pathway, as phenylpropanoids and lignans, or from a mixed biosynthetic pathway (shikimate/ acetate and/or malonate pathways), as stilbenoids or flavonoids.
My thesis is devoted to the family of polyphenols with the specific goal of synthesize new natural-derived polyphenols compounds and study their chemical and biological properties
Dopamine sensing by fluorescent carbon nanoparticles synthesized using artichoke extract
No full textThe practical and easy detection of dopamine levels in human fluids, such as urine and saliva, is of great interest due to the correlation of dopamine concentration with several diseases. In this work, the one-step synthesis of water-soluble carbon nanoparticles (CNPs), starting from artichoke extract, containing catechol groups, for the fluorescence sensing of dopamine is reported. Size, morphology, chemical composition and electronic structure of CNPs were elucidated by DLS, AFM, XPS, FT-IR, EDX and TEM analyses. Their optical properties were then explored by UV-vis and fluorescence measurements in water. The dopamine recognition properties of these CNPs were investigated in water through fluorescence measurements and we observed the progressive enhancement of the CNP emission intensity upon the progressive addition of dopamine, with a binding affinity value of log K = 5.76 and a detection limit of 0.81 nM. Selectivity towards dopamine was tested over other interfering analytes commonly present in human saliva. Finally, in order to perform a solid point of care test, CNPs were adsorbed on a solid support and exposed to different concentrations of dopamine, thus observing a pseudo-linear response, using a smartphone as a detector. Therefore, the detection of dopamine in simulated human saliva was performed with excellent results, in terms of selectivity and a detection limit of 100 pM
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