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Since 2013, bentonite in the form of dioctahedral smectite is an additive authorised in the EU as a substance for the reduction of the contamination of feed by aflatoxins. Several studies indicate a big difference in the effectiveness of bentonites in sequestering aflatoxins. A clear correlation between mineralogical and physicochemical properties of bentonites and aflatoxin adsorption has not been well established. In this study, the most critical mineralogical, chemical, and physical properties that affect aflatoxin adsorption by bentonite were evaluated. Bentonite samples (29), mined from different locations around the world, were analyzed against the published selection criteria for aflatoxin adsorbents: mycotoxin adsorption parameters (maximum adsorption capacity and affinity) determined by the method of adsorption isotherms; pH; cation exchange capacity; particle size distribution; mineralogical/structural compositions; swell index and viscosity. A correlation between geological origin and AFB1 adsorption capacity was found (p

Glyphosate (CAS 1071-83-6) is one of the most widely applied herbicides sprayed against emerged annual, perennial and biennial weeds in all crops including root and tuber vegetables, pulses, oil seeds, and cereals. A new Flow Injection - Tandem Mass Spectrometry (FI-MS/MS) method for the determination of Glyphosate in different matrices was developed and validated. For FI-MS/MS analysis, milled samples were extracted with deionized water, then the extract was cleaned-up by passing it through a polymeric solid phase extraction column. The purified extract was diluted with deionized water prior to FI-MS/MS analysis. FI-MS/MS analysis was performed on a triple quadrupole detector operating in multiple reaction monitoring. Validation data for FI-MS/MS method were satisfactorily compared with acceptability criteria established by Document No. SANTE/11813/2017. To confirm the trueness of data obtained with the FI-MS/MS method, described above, incurred samples, previously characterized for glyphosate by QuPPe method, were analyzed. The applied QuPPe method, was validated according to SANTE/11813/2017 and accredited ISO 17025. Chromatographic separation was conducted by Hypercarb(TM) (100×2.1 mm; 5 ?m) column from Thermo Scientific (Waltham, MA, USA). Incurred chickpea (n=5) and wheat samples (n=6) were selected among samples from official controls of imported products performed by Istituto Zooprofilattico Sperimentale of Umbria and Marche Regions. In particular, chickpeas and wheat samples were from outside EU (Canada, Ukraine, Iran, Russian Federation, USA) and were collected in different ports in central and southern Italy. For incurred chickpea samples a Glyphosate contamination ranging from 16 to 36 mg/Kg was found with both methods, whereas for wheat samples glyphosate concentration ranged from 0.3 to 2 mg/Kg. Good agreement between results obtained by the two methods indicated the FI-MS/MS approach as a valuable alternative to QuPPe method for rapid Glyphosate detection, ensuring high quality of the generated data, and therefore appearing suitable for broad monitoring programs as well as risk assessment purposes.

L'identificazione di genotipi di albicocco con resistenza quantitativa nei confronti del virus della Sharka ha indotto a impiegare tali genotipi in diversi programmi di miglioramento genetico.

Valinomycin (VLM, 1) is a K+ ionophore cyclodepsipeptide capable of depolarizing mitochondria and inducing apoptosis to several mammalian cell types, including a number of tumor cell lines. With the aim of creating VLM-based ligand-targeted anticancer drugs that may selectively convey VLM to pathological cells, we have previously introduced derivatizable hydroxyl handles into the VLM structure, allowing to access a three-entity library of monohydroxyl VLMs (HyVLMs) bearing the OH group at the isopropyl side chain of a d-Hyi, d-Val, or l-Val residue (analogs 2-4, respectively). Herein, the levels of bioactivity retained by the conjugable HyVLMs have been assessed on the basis of their ability to alter the functionality of isolated rat-liver mitochondria. Experiments run with HyVLMs in the range 1-10nM and in 20 or 125mM KCl medium show that the hydroxyl group reduces the potency of HyVLMs relative to VLM to an extent that depends upon the molecular site involved in the hydroxylation. On the other hand, estimation of the stability constants of complexes (in methanol at 25 degrees C) of each analog with Na+, K+, and Cs+ reveals that HyVLMs nicely retain the VLM binding features, except for a moderate increase in the stability of Na+ complexes. These findings, along with pertinent structural considerations, suggest that the incorporation of OH into the VLM structure might actually have altered its K+ transporting ability across mitochondrial membranes. Besides facing new aspects of VLM structure-activity relationship, these studies set the basis for the rational design of ligand-HyVLMs conjugates through derivatization of hanging OH group.

A versatile and rapid method to encapsulate CdSe@ZnS nanocrystals (NCs) in the lipid bilayer of liposomes has been developed. NC surface has been suitably engineered to improve the hydrophobic interaction between NC capping ligand and the lipid alkyl chain. NC-loaded liposomes of various composition were realized by the Micelles to Vesicles Transition (MVT) method [1]. Several NC-loaded liposomes were prepared as a function of NC capping layer, NC concentration, detergent and lipid mixture composition. The properties and the stability of the system have been characterized from the optical (UV-Vis-NIR and emission spectroscopy) and morphological (RT-TEM, Cryo-TEM and DLS analysis) point of view, in order to investigate the optimal experimental conditions for NC-liposome formation. The experimental conditions were tailored to allow the construction of a vesicular hybrid system containing both CdSe@ZnS NCs and reaction centre (RC) protein of Rhodobacter sphaeroides [2]. Absorption spectra suggest that the protein scaffold of RC remained structurally intact in the presence of NCs even after one week. Charge recombination kinetics of RC have confirmed that even at the functional level the protein was not damaged by the NCs. The obtained results are promising and the proposed method could be extended to any type of hydrophobic nanoparticles (metallic, semiconductor, magnetic), lipids and membrane proteins. On the one hand this technique could extend the study of interactions between nanoparticles and proteins to the important class of integral membrane proteins, on the other hand it can be employed to easily produce a non-specific labeling in reconstituted systems and in natural cell membranes using fusogenic techniques. [1] P. Walde, in: H.S. Nalwa (Ed.) Encyclopedia of nanoscience and nanotechnology, American Scientific Publishers, 2003, 1. [2] A. Verméglio, P. Joliot, Trends in Microbiology, 7, 1999, 435.