VALUTAZIONE DELL'EFFETTO DEL TRATTAMENTO CON RADIAZIONI IONIZZANTI SUL CONTENUTO DI MICOTOSSINE NELLA FRUTTA SECCA

Le micotossine sono un gruppo eterogeneo di sostanze chimiche a basso peso molecolare prodotte dal metabolismo secondario di varie specie di funghi tossigeni appartenenti ai generi Aspergillus, Penicillum, Alternaria e Fusarium [1]. Sono molto resistenti al calore e non vengono completamente distrutte durante le normali operazioni di cottura, n\ue9 dai trattamenti fisici, chimici e biologici cui vengono normalmente sottoposte le derrate durante i processi di preparazione degli alimenti. La loro possibile presenza in molti alimenti costituisce oggi un motivo di crescente preoccupazione per la salute dei consumatori poich\ue9 alcune micotossine manifestano caratteristiche di genotossicit\ue0, cancerogenicit\ue0, immunotossicit\ue0, mutagenicit\ue0, nefrotossicit\ue0 e teratogenicit\ue0 [2-4]. Tra i metodi di decontaminazione esistenti ed ampiamente utilizzati, il trattamento degli alimenti con le radiazioni ionizzanti rappresenta un metodo sicuro per ottenere sia una migliore conservazione dei prodotti, sia un controllo delle affezioni alimentari, tramite la riduzione/eliminazione della popolazione patogena [5]. In questo lavoro sono stati valutati gli effetti del processo di irraggiamento con una sorgente di 60Co e dosi comprese tra 0,5 e 3 kGy sul contenuto di micotossine in campioni di frutta secca. In particolare il contenuto di aflatossine G1, G2, B1 e B2, e di ocratossina A (OTA) \ue8 stato valutato, prima e dopo l\u2019irraggiamento, attraverso cromatografia liquida ad alte prestazioni (HPLC) sfruttando le potenzialit\ue0 del rivelatore a fluorescenza. Le analisi HPLC sono precedute da un processo di purificazione del campione che prevede l\u2019utilizzo di colonne di immunoaffinit\ue0 [6-8]. Inoltre sono state valutate le relazioni esistenti tra dose e degradazione delle micotossine

Lipid nanoparticles and active natural compounds: a perfect combination for pharmaceutical applications

Phytochemicals represent an important class of bioactive compounds characterized by significant health benefits. Notwithstanding these important features, their potential therapeutic properties suffer from poor water solubility and membrane permeability limiting their approach to nutraceutical and pharmaceutical applications. Lipid nanoparticles are well known carrier systems endowed with high biodegradation and an extraordinary biocompatible chemical nature, successfully used as platform for advanced delivery of many active compounds, including the oral, topical and systemic routes. This article is aimed at reviewing the last ten years of studies about the application of lipid nanoparticles in active natural compounds reporting examples and advantages of these colloidal carrier systems

Metabolic characterization of supernatants produced by Lactobacillus spp. With in vitro anti-Legionella activity

Legionella pneumophila is an organism of public health interest for its presence in water supply systems and other humid thermal habitats. In this study, ten cell-free supernatants produced by Lactobacillus strains were evaluated for their ability to inhibit L. pneumophila strains isolated from hot tap water. Production of antimicrobial substances by Lactobacillus strains were assessed by agar well diffusion test on BCYE agar plates pre-inoculated with L. pneumophila. Cell-free supernatants (CFS) showed antimicrobial activity against all Legionella strains tested: L. rhamnosus and L. salivarius showed the highest activity. By means of a proton-based nuclear magnetic resonance (1H-NMR) spectroscopy, we detected and quantified the Lactobacillus metabolites of these CFSs, so to gain information about which metabolic pathway was likely to be connected to the observed inhibition activity. A panel of metabolites with variations in concentration were revealed, but considerable differences among inter-species were not showed as reported in a similar work by Foschi et al. (2018). More than fifty molecules belonging mainly to the groups of amino acids, organic acids, monosaccharides, ketones, and alcohols were identified in the metabolome. Significant differences were recorded comparing the metabolites found in the supernatants of strains grown in MRS with glycerol and the same strains grown in MRS without supplements. Indeed, pathway analysis revealed that glycine, serine and threonine, pyruvate, and sulfur metabolic pathways had a higher impact when strains were grown in MRS medium with a supplement such as glycerol. Among the metabolites identified, many were amino acids, suggesting the possible presence of bacteriocins which could be linked to the anti-Legionella activity shown by cell-free supernatants

Dual-drugs delivery in Solid Lipid Nanoparticles for the treatment of Candida albicans mycosis

Supplementary material related to this article can be found, in the online version, at doi: https://doi.org/10.1016/j.colsurfb.2019.110705.Nowadays, a combinatorial drug delivery system that simultaneously transports two or more drugs to the targeted site in a human body, also recognized as a dual-drugs delivery system, represents a promising strategy to overcome drug resistance. Solid lipid nanoparticles loaded with clotrimazole (CLZ) and alphalipolic acid (ALA), considered as an effective agent in the reduction of reactive oxygen species, can enhance anti-infective immunity being proposed as a non-toxic and mainly non-allergic dual-drugs delivery system. In this study, uncoated and cationic CLZ-ALA-loaded SLN were prepared and compared. Suspensions with a narrow size distribution of particles of mean size below 150?nm were obtained, having slight negative or highly positive zeta potential values, due to the presence of the cationic lipid, which also increased nanoparticles stability, as confirmed by Turbiscan® results. Calorimetric studies confirmed the rationale of separately delivering the two drugs in a dual-delivery system. Furthermore, they confirmed the formation of SLN, without significant variation in presence of the cationic lipid. In vitro release studies showed a prolonged drug release without the occurrence of any burst effect. In vitro studies performed on 25 strains of Candida albicans showed the antimicrobial drug activity was not altered when it was loaded into lipid nanoparticles. The study has proved the successfully encapsulation of CLZ and ALA in solid lipid nanoparticles that may represent a promising strategy to combine ALA protective effect in the treatment with CLZ.This research was financed by Research Funding for University of Catania, under Project Piano per la Ricerca 2016-2018 – Linea Di Intervento2“DotazioneOrdinaria”cod.57722172106.info:eu-repo/semantics/publishedVersio