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1.
Materials (Basel) ; 17(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38793370

RESUMEN

In recent times, circular economy initiatives in addition to the need for sustainable biomaterials have brought about several attempts at the eco-friendly, eco-sustainable and cost-effective production of asphalt pavements. It is an increasingly common practice in the asphalt industry to improve road pavement performance using additives to enhance the physico-chemical properties of bitumen, which performs the role of the binder in the asphalt mix. This paper evaluated the potential of a bio-based additive derived from olive leaf residue as a modifier and antioxidant agent for bitumen. Samples of neat, aged and doped aged bitumen were analyzed. In this study, the two bio-based additives were characterized in terms of phenol, chlorophyll, lignin and cellulose content, which was correlated with the mechanical properties of the tested samples. The mechanical properties of the neat, modified, aged and unaged samples were evaluated via Dynamic Shear Rheology. The bio-based additives proved to be promising and can improve the properties of bitumen binder and the performance of asphalt pavements in general.

2.
Phys Chem Chem Phys ; 25(38): 26014-26022, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37740358

RESUMEN

This work investigates the relationship between the structure and physicochemical properties of three different starches in starch/polyvinyl alcohol aqueous solutions. For this purpose, accurate nuclear magnetic resonance (NMR) analyses were performed to determine the role that the starch structure plays in the formation of binder solutions. Moreover, a dynamic shear rheometer (DSR) was used to investigate the mechanical properties of the solutions and correlate them with the structure of each starch. Complete characterization of the analysed starches and the starch/PVOH solutions was also carried out through light scattering measurements. Furthermore, by crossing the data coming from NMR and light scattering with those coming from rheology, the best solution was identified. Finally, to confirm the interaction mechanism between starch and PVOH, thermogravimetric analysis and an NMR study, using 1H and 13C NMR spectra, were carried out on the film obtained from the best solution. The analyses carried out showed that PVOH has a stabilizing effect on starch/PVOH solutions, and the starch with the greatest branching degree is the one that forms a more structured network.

3.
Int J Mol Sci ; 24(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36768417

RESUMEN

In recent years, the food industry has become increasingly involved in researching vegetable fats and oils with appropriate mechanical properties (ease of transport, processing, and storage) and a specific lipidic composition to ensure healthy products for consumers. The chemical-physical behavior of these matrices depends on their composition in terms of single fatty acids (FA). However, as we demonstrate in this work, these properties, as well as the absorption, digestion and uptake in humans of specific FAs, are also largely determined by their regiosomerism within the TriAcylGlycerols (TAG) moieties (sn-1,2,3 positions). The goal of this work is to study for the first time vegetable fats obtained directly from a sample of natural cocoa butter (CB) through a process that manipulates the distribution of FAs but not their nature. Even if the initial percentage of each FA in the mixture remains the same, CB derivatives seem to show improved chemical-physical features. In order to understand which factors account for their physical and chemical characteristics, and to check whether or not the obtained new matrices could be considered as valid alternatives to other vegetable fats (e.g., palm oil (PO)), we carried out an experimental investigation at both the macroscopic and molecular level including: (i) Differential Scanning Calorimetry (DSC) analyses to examine thermal features; (ii) rheological testing to explore mechanical properties; (iii) powder X-ray diffraction (PXRD) to evaluate the solid-state phases of the obtained fats; and (iv) 1H and 13C Nuclear Magnetic Resonance (NMR, 1D and 2D) spectroscopy to rapidly analyze fatty acid composition including regioisomeric distribution on the glycerol backbone. These last results open up the possibility of using NMR spectroscopy as an alternative to the chromatographic techniques routinely employed for the investigation of similar matrices.


Asunto(s)
Grasas de la Dieta , Ácidos Grasos , Humanos , Triglicéridos/química , Rayos X , Rastreo Diferencial de Calorimetría , Grasas de la Dieta/análisis , Ácidos Grasos/química , Grasas , Espectroscopía de Resonancia Magnética
4.
Molecules ; 27(11)2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35684451

RESUMEN

Cannabis sativa is a herbaceous multiple-use species commonly employed to produce fiber, oil, and medicine. It is now becoming popular for the high nutritional properties of its seed oil and for the pharmacological activity of its cannabinoid fraction in inflorescences. The present study aims to apply nuclear magnetic resonance (NMR) spectroscopy to provide useful qualitative and quantitative information on the chemical composition of seed and flower Cannabis extracts obtained by ultra-sound-assisted extraction, and to evaluate NMR as an alternative to the official procedure for the quantification of cannabinoids. The estimation of the optimal ω-6/ω-3 ratio from the 1H NMR spectrum for the seed extracts of the Futura 75 variety and the quantitative results from the 1H and 13C NMR spectra for the inflorescence extracts of the Tiborszallasi and Kompolti varieties demonstrate that NMR technology represents a good alternative to classical chromatography, supplying sufficiently precise, sensitive, rapid, and informative data without any sample pre-treatment. In addition, different extraction procedures were tested and evaluated to compare the elaboration of spectral data with the principal component analysis (PCA) statistical method and the quantitative NMR results: the extracts obtained with higher polarity solvents (acetone or ethanol) were poor in psychotropic agents (THC < LOD) but had an appreciable percentage of both cannabinoids and triacylgliceroles (TAGs). These bioactive-rich extracts could be used in the food and pharmaceutical industries, opening new pathways for the production of functional foods and supplements.


Asunto(s)
Cannabinoides , Cannabis , Cannabinoides/química , Cannabis/química , Inflorescencia/química , Espectroscopía de Resonancia Magnética , Extractos Vegetales/química
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