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Ethanol is one of the major components of wine, which has a substantial impact on its sensory characteristics. However, data concerning consumer response to ethanol or changes in ethanol remains limited. The aim of this study was to determine the threshold ethanol concentrations beyond which ethanol lowering becomes undesirable in Chardonnay and Syrah wines using the consumer rejection threshold (CRT) methodology. Base wines from these two cultivars were first dearomatised and fully dealcoholised using spinning cone column technology. Then, control wines with a similar ethanol content to the base wines (13.8 and 13.5 % v/v for Chardonnay and Syrah respectively) and wines with lower ethanol contents were reconstituted by mixing the final beverage, the aroma fraction, food grade ethanol and distilled water. CRT values were determined as 2.8 % v/v for Chardonnay and at 7.0 % v/v for Syrah. These particularly low and unexpected concentrations indicate that consumer sensory liking might not be necessarily driven by ethanol concentration, especially for white wines. However, the post-evaluation questionnaire showed that consumers were expecting a high minimal ethanol content for quality wines (10.9 % v/v ± 1.2 and 11.7 % v/v ± 1.5 for white and red wines respectively) and had a limited experience with low and dealcoholised wines. Overall, our data, which are still preliminary and deserve to be validated using different base wines with a larger number of consumers, show that consumers would not necessarily be refractory from a sensory standpoint to the consumption of low ethanol beverages made from wine. Our findings strongly encourage professionals from the wine industry and public authorities to raise awareness about the increase in quality of such products and their benefits for human health.

This paper deals with the use of tetrabutylammonium fluoride/dimethylsulfoxide (TBAF/DMSO) to characterize the molar mass distribution of non-derivatized cellulosic samples by size exclusion chromatography (SEC). Different cellulose samples with various average degree of polymerization (DP) were first solubilized in this solvent system, with increasing TBAF rates, and then analyzed by SEC coupled to a refractive index detector (RID), using DMSO as mobile phase. The Molar Masses (MM) obtained by conventional calibration were then discussed and compared with suppliers’ data and MM determined by viscosimetry measurements. By this non-classic method, molar mass of low DP samples (Avicel® and cotton fibers) have been determined. For high DP samples (α-cellulose and Vitacel®), dissolution with TBAF concentration of 10 mg/mL involved elution of cellulose aggregates in the exclusion volume, related to an incomplete dissolution or the dilution of TBAF molecules in elution solvent, preventing the correct evaluation of their molar mass.

Drug delivery by nanovectors involves numerous processes, one of the most important being its release from the carrier. This point still remains unclear. The current work focuses on this point using poly(ethyleneglycol-b-ε-caprolactone) micelles containing either pheophorbide-a (Pheo-a) as a fluorescent probe and a phototoxic agent or fluorescent copolymers. This study showed that the cellular uptake and the phototoxicity of loaded Pheo-a are ten times higher than those of the free drug and revealed a very low cellular penetration of the fluorescence-labeled micelles. Neither loaded nor free Pheo-a displayed the same cellular localization as the labeled micelles. These results imply that the drug entered the cells without its carrier and probably without a disruption, as suggested by their stability in cell culture medium. These data allowed us to propose that Pheo-a directly migrates from the micelle to the cell without disruption of the vector. This mechanism will be discussed.

Abstract High and low pathogenicity avian influenza viruses (HPAIV, LPAIV) are the primary causes of poultry diseases worldwide. HPAIV and LPAIV constitute a major threat to the global poultry industry. Therefore, early detection and well-adapted surveillance strategies are of the utmost importance to control the spread of these viruses. Volatile Organic Compounds (VOCs) released from living organisms have been investigated over the last decades as a diagnostic strategy. Mass spectrometry instruments can analyze VOCs emitted upon viral infection. Selected ion flow tube mass spectrometry (SIFT-MS) enables direct analysis of cell headspace in less than 20 min. As a proof-of-concept study, we investigated the ability of a SIFT-MS coupled sparse Partial Least Square-Discriminant Analysis analytical workflow to discriminate IAV-infected cells. Supernatants of HPAIV, LPAIV, and control cells were collected from 1 to 72 h post-infection and analyzed using our analytical workflow. At each collection point, VOCs' signatures were first identified based on four independent experiments and then used to discriminate the infectious status of external samples. Our results indicate that the identified VOCs signatures successfully discriminate, as early as 1-h post-infection, infected cells from the control cells and differentiated the HPAIV from the LPAIV infection. These results suggest a virus-dependent VOCs signature. Overall, the external samples' status was identified with 96.67% sensitivity, 100% specificity, and 97.78% general accuracy.

Incorporation of unaggregated monomeric molecules of pheophorbide(a) into micelles of poly(ethyleneoxide-b--caprolactone) has been characterized by fluorescence spectroscopy, dynamic light scattering, transmission electron microscopy and asymmetric flow field flow fractionation. It was shown that the method used leads to 20 nm micelles, corresponding to approximately 200 molecules of polymer and 4 molecules of monomeric pheophorbide(a) per nano-object which was able to generate 1O2in the medium. They have been used thereafter as nanocarriers for photosensitizers in photodynamic therapy against cancer cells. The encapsulation of photosensitizer has been verified and in vitrotests on human cancerous cells have revealed a ca.2-fold enhanced photocytotoxicity and cellular uptake compared to free pheophorbide(a). [ABSTRACT FROM AUTHOR]

Industrial gelatins have different physicochemical properties that mainly depend of the raw materials origin and the extraction conditions. These properties are closely related to the molar mass distribution of these gelatins. Several methods exist to characterize molar mass distribution of polymer, including the Asymmetrical Flow Field Flow Fractionation method. The goal of this study is to analyze the relationship between physicochemical properties and the gelatins molar mass distribution obtained by Asymmetrical Flow Field Flow Fractionation. In this study, 49 gelatins samples extracted from pig skin are characterized in terms of gel strength and viscosity and their molar mass distribution are analyzed by Asymmetrical Flow Field Flow Fractionation coupled to an Ultraviolet and Multi Angle Light Scattering detector. This analytical method is an interesting tool for studying, simultaneously, the primary chains and the high-molar-mass fraction corresponding to the polymer chains. Correlation analysis between molar mass distribution data from the different fractions highlights the importance of high molar mass polymer chains to explain the gel strength and viscosity of gelatins. These results are confirmed by an additional chemometric approach based on the UV absorbance of gelatin fractograms to predict gel strength (r2Cal = 0.85) and viscosity (r2Cal = 0.79).

The objective of this work was to assess the relation between the purity of polymeric self-assemblies vectors solution and their photodynamic therapeutic efficiency. For this, several amphiphilic block copolymers of poly(ethyleneoxide-b-ε-caprolactone) have been used to form self-assemblies with different morphologies (micelles, worm-like micelles or vesicles). In a first step, controlled mixtures of preformed micelles and vesicles have been characterized both by dynamic light scattering and asymmetrical flow field flow fractionation (AsFlFFF). For this, a custom-made program, STORMS, was developed to analyze DLS data in a thorough manner by providing a large set of fitting parameters. This showed that DLS only sensed the larger vesicles when the micelles/vesicles ratio was 80/20 w/w. On the other hand, AsFlFFF allowed clear detection of the presence of micelles when this same ratio was as low as 10/90. Subsequently, the photodynamic therapy efficiency of various controlled mixtures was assessed using multicellular spheroids when a photosensitizer, pheophorbide a, was encapsulated in the polymer self-assemblies. Some mixtures were shown to be as efficient as monomorphous systems. In some cases, mixtures were found to exhibit a higher PDT efficiency compared to the individual nano-objects, revealing a synergistic effect for the efficient delivery of the photosensitizer. Polymorphous vectors can therefore be superior in therapeutic applications. [ABSTRACT FROM AUTHOR]