Fast method for the determination of short-chain-length polyhydroxyalkanoates (scl-PHAs) in bacterial samples by In Vial-Thermolysis (IVT)

none8siA new method based on the GC–MS analysis of thermolysis products obtained by treating bacterial samples at a high temperature (above 270 C) has been developed. This method, here named “In-Vial- Thermolysis” (IVT), allowed for the simultaneous determination of short-chain-length polyhydrox- yalkanoates (scl-PHA) content and composition. The method was applied to both single strains and microbial mixed cultures (MMC) fed with different carbon sources. The IVT procedure provided similar analytical performances compared to previous Py-GC–MS and Py- GC-FID methods, suggesting a similar application for PHA quantitation in bacterial cells. Results from the IVT procedure and the traditional methanolysis method were compared; the correlation between the two datasets was fit for the purpose, giving a R2 of 0.975. In search of further simplification, the rationale of IVT was exploited for the development of a “field method” based on the titration of thermolyzed samples with sodium hydrogen carbonate to quantify PHA inside bacterial cells. The accuracy of the IVT method was fit for the purpose. These results lead to the possibility for the on-line measurement of PHA productivity. Moreover, they allow for the fast and inexpensive quantification/characterization of PHA for biotechnological process control, as well as investigation over various bacterial communities and/or feeding strategies.mixedF. Abbondanzi; G. Biscaro; G. Carvalho; L. Favaro; P. Lemos; M. Paglione; C. Samorì; C. TorriF. Abbondanzi; G. Biscaro; G. Carvalho; L. Favaro; P. Lemos; M. Paglione; C. Samorì; C. Torr

Grape pomace for topical application: Green nades sustainable extraction, skin permeation studies, antioxidant and anti-inflammatory activities characterization in 3d human keratinocytes

Food waste is a global problem due to its environmental and economic impact, so there is great demand for the exploitation of new functional applications. The winemaking process leads to an incomplete extraction of high-value compounds, leaving the pomace still rich in polyphenols. This study was aimed at optimising and validating sustainable routes toward the extraction and further valorisation of these polyphenols, particularly for cosmeceutical applications. New formulations based on red grape pomace polyphenols and natural deep eutectic solvents (NaDESs) were here investigated, namely betaine combined with citric acid (BET-CA), urea (BET-U) and ethylene glycol (BET-EG), in which DESs were used both as extracting and carrying agents for polyphenols. The flavonoid profile determined by HPLC-MS/MS analysis showed similar malvidin content (51\u201356 \ub5g mL 121 ) in the DES combinations, while BET-CA gave the best permeation performance in Franz cells, so it was further investigated in 3D human keratinocytes (HaCat spheroids) injured with the pro-oxidant agent menadione. BET-CA treatment showed good intracellular antioxidant activity (IC50 0.15 \ub1 0.02 \ub5g mL 121 in malvidin content) and significantly decreased (p < 0.001) the release of the pro-inflammatory cytokine IL-8, improving cell viability. Thus, BET-CA formulation is worthy of investigation for potential use as a cosmetic ingredient to reduce oxidative stress and inflammation, which are causes of skin aging

Mesoscopic 3D Charge Transport in Solution-Processed Graphene-Based Thin Films: A Multiscale Analysis

Graphene and related 2D material (GRM) thin films consist of 3D assembly of billions of 2D nanosheets randomly distributed and interacting via van der Waals forces. Their complexity and the multiscale nature yield a wide variety of electrical characteristics ranging from doped semiconductor to glassy metals depending on the crystalline quality of the nanosheets, their specific structural organization ant the operating temperature. Here, the charge transport (CT) mechanisms are studied that are occurring in GRM thin films near the metal-insulator transition (MIT) highlighting the role of defect density and local arrangement of the nanosheets. Two prototypical nanosheet types are compared, i.e., 2D reduced graphene oxide and few-layer-thick electrochemically exfoliated graphene flakes, forming thin films with comparable composition, morphology and room temperature conductivity, but different defect density and crystallinity. By investigating their structure, morphology, and the dependence of their electrical conductivity on temperature, noise and magnetic-field, a general model is developed describing the multiscale nature of CT in GRM thin films in terms of hopping among mesoscopic bricks, i.e., grains. The results suggest a general approach to describe disordered van der Waals thin films

In Vivo Analysis of the Role of O-Glycosylations of Von Willebrand Factor

The objective of this project was to study the function of O-glycosylations in von Willebrand factor (VWF) life cycle. In total, 14 different murine Vwf cDNAs mutated on one or several O-glycosylations sites were generated: 9 individual mutants, 2 doublets, 2 clusters and 1 mutant with all 9 murine glycosylation sites mutated (Del-O-Gly). We expressed each mutated cDNA in VWF deficient-mice by hydrodynamic injection. An immunosorbent assay with Peanut Agglutinin (PNA) was used to verify the O-glycosylation status. Wild-type (WT) VWF expressed by hepatocytes after hydrodynamic injection was able to bind PNA with slightly higher affinity than endothelial-derived VWF. In contrast, the Del-O-Gly VWF mutant did not bind PNA, demonstrating removal of O-linked glycans. All mutants displayed a normal multimeric pattern. Two mutants, Del-O-Gly and T1255A/T1256A, led to expression levels 50% lower than those induced by WT VWF and their half-life in vivo was significantly reduced. When testing the capacity of each mutant to correct the bleeding time of VWF-deficient mice, we found that S1486A, T1255A, T1256A and the doublet T1255A/T1256A were unable to do so. In conclusion we have shown that O-glycosylations are dispensable for normal VWF multimerization and biosynthesis. It also appears that some O-glycosylation sites, particularly the T1255 and T1256 residues, are involved in the maintenance of VWF plasma levels and are essential for normal haemostasis. As for the S1486 residue, it seems to be important for platelet binding as demonstrated in vitro using perfusion experiments

Growth and nitrogen removal capacity of Desmodesmus communis and of a natural microalgae consortium in a batch culture system in view of urban wastewater treatment (Part I).

The microalgal biomass applications strongly depend on cell composition and the production of low cost products such as biofuels appears to be economically convenient only in conjunction with wastewater treatment. As a preliminary study, in view of the development of a wastewater treatment pilot plant for nutrient removal and algal biomass production, a biological wastewater system was carried out on a laboratory scale growing a newly isolated freshwater algal strain, Desmodesmus communis, and a natural consortium of microalgae in effluents generated by a local wastewater reclamation facility. Batch cultures were operated by using D. communis under different growth conditions to better understand the effects of CO2, nutrient concentration and light intensity on the biomass productivity and biochemical composition. The results were compared with those obtained using a natural algal consortium. D. communis showed a great vitality in the wastewater effluents with a biomass productivity of 0.138 - 0.227 g L-1 d-1 in the primary effluent enriched with CO2, higher biomass productivity compared with the one achieved by the algal consortium (0.078 g L-1 d-1). D. communis cultures reached also a better nutrient removal efficiency compared with the algal consortium culture, with almost 100% for ammonia and phosphorous at any N/P ratio characterizing the wastewater nutrient composition. Biomass composition was richer in polysaccharides and total fatty acids as the ammonia concentration in the water decreased. In view of a future application of this algal biomass, due to the low total fatty acids content of 1.4 - 9.3 wt% and the high C/N ratio of 7.6 - 39.3, anaerobic digestion appeared to be the most appropriate biofuel conversion process

Algal flocculation induced by homogeneous and heterogeneous acid treatments in Desmodesmus communis

Flocculation induced by pH decrease is here presented as a solution to pre-concentrate algal cultures of species belonging to Scenedesmaceae and preserve the integrity of the biomass, while maintaining the photosynthetic capacity of non-harvested cells. The low-pH flocculation method gives highly effective results exclusively by the strength of the acid (hydrochloric or formic) used for the treatment, and is applicable to cultures having high cell densities (N2 g L 121). High flocculation efficiencies (N90%) are obtained also by using heterogeneous acids, such as solid acid carbons from naturally available compounds, which are proposed as cheap recyclable materials to be exploited for this purpose. Additionally, the potential reuse of the filtered medium(sterilized or not) and of the supernatant (containing non-harvested cells) is investigated to avoid great water losses and to re-inoculate new cultures

LIQUIDI IONICI: VALUTAZIONE DELL\u2019ECOTOSSICIT\uc0 E DEGLI EFFETTI BIOLOGICI

Gli aspetti (eco)tossicologici dei liquidi ionici, ed in generale la loro modalit\ue0 di interazione con gli esseri viventi, sono stati valutati su vari tipi di organismi bersaglio acquatici, tra cui invertebrati, alghe, batteri e su sistemi modello cellulari ed artificiali. La tossicit\ue0 \ue8 modulata principalmente dal carattere anfifilico delle sostanze, che determina la modalit\ue0 di interazione con le membrane cellulari