Antioxidant activity of phenolic extracts from different cultivars of Italian onion (Allium cepa) and relative human immune cell proliferative induction

The total antioxidant activity (TAC) may vary considerably between onion cultivars. Immunological effects of onion phenolic compounds are still underestimated.The objective of this study is to determine the total phenol content (TPC) and the relative TAC of three Allium cepa L. (Liliaceae) onion cultivars cultivated in Cannara (Italy): Rossa di Toscana, Borettana di Rovato, and Dorata di Parma, and to evaluate the phenol extracts ability to induce human immune cell proliferation.TPC was determined by the Folin-Ciocalteu method, TAC with FRAP, TEAC/ABTS, and DPPH methods. Peripheral blood mononuclear cells from healthy human donors were incubated for 24 h at 37 °C with 1 ng/mL of phenolic extract in PBS, immunostained, and then analyzed by 4-color flow cytometry for the phenotypic characterization of T helper cells (CD4+ cells), cytotoxic T lymphocytes (CD8+ cells), T regulatory cells (CD25high CD4+ cells), and natural killer cells/monocytes (CD16+ cells).Rossa di Toscana displayed the highest TPC (6.61 ± 0.87 mg GA equivalents/g onion bulb DW) and the highest TAC with the experienced methods: FRAP, 9.19 ± 2.54 μmol Trolox equivalents/g onion bulb DW; TEAC/ABTS, 21.31 ± 0.41 μmol Trolox equivalents/g onion bulb DW; DPPH, 22.90 ± 0.01 μmol Trolox equivalents/g onion bulb DW. Incubation with Rossa di Toscana extract determined an increase in the frequency of the antitumor/anti-infection NK CD16+ immune cells (23.0 ± 0.4%).Content of health-promoting phenols and the deriving antioxidant and immunostimulating activity vary considerably among the investigated cultivars. Rossa di Toscana can be considered as a potential functional food

Dried Volumetric Microsampling Approaches for the Therapeutic Drug Monitoring of Psychiatric Patients Undergoing Clozapine Treatment

Clozapine is one of the most widely used second-generation antipsychotic drugs (SGAs) for the treatment of schizophrenia. Despite advantages over first-generation drugs, clozapine still shows significant side effects and interindividual variations in efficacy. In order to ensure frequent therapeutic drug monitoring (TDM) and improve the compliance of psychiatric patients undergoing clozapine treatment, two novel dried microsampling approaches based on whole blood and plasma volumetric absorptive microsampling (b-VAMS and p-VAMS) and microfluidic generated-dried blood spot technology (mfDBS) were developed and coupled to HPLC with electrochemical detection (ED). The proposed miniaturized strategies by means of VAMS and microfluidic channel-based devices provide several advantages in terms of collection, storage, and handling compared to classical blood and plasma processing. Satisfactory validation results were obtained for all microsampling platforms, with mean extraction yields >85.1%, precision as relative standard deviation (RSD) < 5.1%, and stability < 4.5% analyte loss after 30 days for p-VAMS; mean extraction yields > 83.4%, precision RSD < 5.4%, and stability < 4.6% analyte loss after 30 days for b-VAMS, and mean extraction yields > 74.0%, precision RSD < 5.6%, and stability < 4.9% analyte loss after 30 days for mfDBS. The original microsampling methodologies have been successfully applied to the blood and plasma collected from five psychiatric patients for the monitoring of the levels of clozapine and its main metabolites, providing robust and reliable quali-quantitative results. Comparisons between results of the two dried microsampling technologies with those obtained by classic fluid plasma analysis were in good agreement and have demonstrated that the proposed miniaturized approaches could be suitable for TDM purposes

VALIDATED PUNGENCY ASSESSMENT OF THREE ITALIAN ONION (ALLIUM CEPA L.) CULTIVARS

Abstract In the frame of a broad multidisciplinary study aimed at enlightening the peculiarities of three onion cultivars (Dorata di Parma, Borettana and Rossa di Toscana

Use of a Zwitterionic Surfactant to Improve the Biofunctional Properties of Wool Dyed with an Onion (Allium cepa L.) Skin Extract

To improve the loadability and antioxidant properties of wool impregnated with onion skin extract, the introduction of SB3-14 surfactant in the dyeing process was evaluated. A preliminary investigation on the surfactant–quercetin interaction indicated that the optimal conditions for dye solubility, stability, and surfactant affinity require double-distilled water (pH = 5.5) as a medium and SB3-14 in a concentration above the c.m.c. (2.5 × 10−3 M). The absorption profile of textiles showed the flavonoid absorption band (390 nm) and a bathochromic feature (510 nm), suggesting flavonoid aggregates. The higher absorbance for the sample dyed with SB3-14 indicated greater dye uptake, which was further confirmed by HPLC analysis. The Folin–Ciocalteu method was applied to evaluate the total phenol content (TPC) released from the treated wool, while the assays FRAP, DPPH, ABTS, and ORAC were applied to evaluate the corresponding total antioxidant activity (TAC). Higher TPCs (about 20%) and TACs (5–55%) were measured with SB3-14, highlighting textiles with improved biofunctional properties. Spectrophotometric analyses were also performed with an artificial sweat. The potential cytotoxic effect of SB3-14 in both monomeric and aggregated forms, cell viability, and induction of apoptosis were evaluated in RAW 264.7 cells. These analyses revealed that SB3-14 is safe at concentrations below the c.m.c

3-hydroxy-L-kynurenamine is an immunomodulatory biogenic amine

Tryptophan catabolism is a major metabolic pathway utilized by several professional and non-professional antigen presenting cells to maintain immunological tolerance. Here we report that 3-hydroxy-l-kynurenamine (3-HKA) is a biogenic amine produced via an alternative pathway of tryptophan metabolism. In vitro, 3-HKA has an anti-inflammatory profile by inhibiting the IFN-gamma mediated STAT1/NF-kappa Beta pathway in both mouse and human dendritic cells (DCs) with a consequent decrease in the release of pro-inflammatory chemokines and cytokines, most notably TNF, IL-6, and IL12p70. 3-HKA has protective effects in an experimental mouse model of psoriasis by decreasing skin thickness, erythema, scaling and fissuring, reducing TNF, IL-1 beta, IFN-gamma, and IL-17 production, and inhibiting generation of effector CD8(+) T cells. Similarly, in a mouse model of nephrotoxic nephritis, besides reducing inflammatory cytokines, 3-HKA improves proteinuria and serum urea nitrogen, overall ameliorating immune-mediated glomerulonephritis and renal dysfunction. Overall, we propose that this biogenic amine is a crucial component of tryptophan-mediated immune tolerance. 3-hydroxy-L-kynurenamine (3-HKA) is a metabolite deriving from a lateral pathway of tryptophan catabolism. Here the authors identify 3-HKA as a biogenic amine and show it has anti-inflammatory properties that can protect mice against psoriasis and nephrotoxic nephritis.Peer reviewe

Ketamine chiral analysis in alternative and innovative biological samples

Ketamine ((R,S-2-(2-chlorophenyl)-2-methylamino)cyclohexanone) is a phencyclidine derivative used in human and veterinary clinical practice since 1970. It is a dissociative anaesthetic agent that induces also analgesia by non-opioid mechanisms. Ketamine causes a state of "dissociative anaesthesia", for this reason is used as a recreational drug and has been included in the controlled substance schedules of most countries. As an anaesthetic drug, Ketamine is commercially available as a racemic mixture however, (R)-Ketamine and (S)-Ketamine have significantly different pharmacodynamic activities: the therapeutic potency of (S)-Ket is 2-4 times greater than the that of the (R)-enantiomer, as regards anaesthetic and analgesic effects. Moreover, the post-hypnotic stimulatory properties and agitated behaviour are associated with (R)-Ket. On the other hand, even if Ketamine hallucinogenic potency is still largely unclear, some authors claim that the (R)-enantiomer is the most potent one. It has also been reported that (R)- and (S)-Ket have significantly different pharmacokinetic profiles. Thus, it is evident the need to provide analytical methods able to discriminate and simultaneously quantify both Ketamine enantiomers in biological matrices for pharmacokinetic, toxicological and forensic purposes. The aim of this study is the development of an analytical method for Ketamine chiral analysis in alternative and innovative biological fluids and tissues, such as Dried Blood Spots (DBSs), saliva and hair. Different chromatographic setups were tested to obtain a good enantioseparation by liquid chromatography with fluorimetric detection (HPLC-F). The assays are currently under validation and seem to be promising for a successfull Ketamine enantiomeric resolution and determination, in order to be applied to real biological samples

Ketoprofen enantioseparation with a Cinchona alkaloid based stationary phase: enantiorecognition mechanism and release studies

With the present contribution, we demonstrate that the baseline separation of ketoprofen enantiomers can be successfully achieved (α = 1.09; R(S) = 1.60) in the reversed-phase mode of elution with a commercially available anion-exchange-based chiral stationary phase, incorporating the quinine 2,6-diisopropylphenyl carbamate derivative as the enantioresolving unit. Focused modification of the eluent composition indicated a stereoselective role of hydrophobic and π-π interactions between the selector and selectand units, besides the prime ionic intermolecular interaction. The mechanistic hypotheses based on the chromatographic data were confirmed by in silico molecular dynamic simulations, which allowed us to establish the network of selector-selectand interactions underlying the stereorecognition process at a molecular level. The validated method was successfully used to evaluate the drug content and release profile of ketoprofen-loaded polymeric film, showing drug homogeneous distribution into the film and no preferential interactions between the polymer and one of the enantiomers, with the racemate released at each time point

Rapid detection of D-amino acids in cheese with a chiral ligand-exchange chromatography system

Due to the well established difference in the pharmaco/toxicological profile of many amino acid enantiomers, and also for typifying the food quality and origin, the exact knowledge of their presence and relative ratio in foodstuffs, is a matter of growing interest. In this setting, with an interest in identifying the presence of D-amino acids in a selected set of cheese samples, and with the aim to introduce a fast and easily accessible chromatographic procedure, we analyzed six cheese extracts with a CLEC-based chiral stationary phase (CLEC-CSP). The CLEC analyses were run without any pre-or post-column derivatization of the amino acidic mixture. The successful chemo- and enantioseparation were contemporarily achieved with the use of a dynamically coated CSP (C-CSP) based on the S-trityl-L-cysteine (L-STC) as the chiral selector. With the applied CLEC procedure, the presence of D-Ala, D-Asp and D-Glu was diagnosed in all the analyzed samples and then confirmed via conventional chiral gas chromatographic (CGC) analysis. A certain degree of peak overlapping was found to be the main drawback of the simplified sample analysis, which is nevertheless balanced by the advantages of the rapid detection. © 2012 Bentham Science Publishers.Peer Reviewe

Synthesis and Quantitative Structure-Property Relationships of Side Chain-Modified Hyodeoxycholic Acid Derivatives

Bile acids have emerged as versatile signalling compounds of a complex network of nuclear and membrane receptors regulating various endocrine and paracrine functions. The elucidation of the interconnection between the biological pathways under the bile acid control and manifestations of hepatic and metabolic diseases have extended the scope of this class of steroids for in vivo investigations. In this framework, the design and synthesis of novel biliary derivatives able to modulate a specific receptor requires a deep understanding of both structure-activity and structure-property relationships of bile acids. In this paper, we report the preparation and the critical micellization concentration evaluation of a series of hyodeoxycholic acid derivatives characterized by a diverse side chain length and by the presence of a methyl group at the alpha position with respect to the terminal carboxylic acid moiety. The data collected are instrumental to extend on a quantitative basis, the knowledge of the current structure-property relationships of bile acids and will be fruitful, in combination with models of receptor activity, to design and prioritize the synthesis of novel pharmacokinetically suitable ligands useful in the validation of bile acid-responsive receptors as therapeutic targets