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2022
Rodrigo, {AP }, Lopes {AC}, Pereira R, Anjo {SI }, Manadas B, Grosso {AR }, Baptista {PV}, Fernandes {AR}, Costa {PM }.  2022.  Endogenous Fluorescent Proteins in the Mucus of an Intertidal Polychaeta: Clues for Biotechnology, mar. Marine Drugs. 20, Number 4: MDPI - Multidisciplinary Digital Publishing Institute Abstract

The vast ocean holds many unexplored organisms with unique adaptive features that enable them to thrive in their environment. The secretion of fluorescent proteins is one of them, with reports on the presence of such compounds in marine annelids being scarce. The intertidal Eulalia sp. is an example. The worm secretes copious amounts of mucus, that when purified and concentrated extracts, yield strong fluorescence under UV light. Emission has two main maxima, at 400 nm and at 500 nm, with the latter responsible for the blue–greenish fluorescence. Combining proteomics and transcriptomics techniques, we identified ubiquitin, peroxiredoxin, and 14-3-3 protein as key elements in the mucus. Fluorescence was found to be mainly modulated by redox status and pH, being consistently upheld in extracts prepared in Tris-HCl buffer with reducing agent at pH 7 and excited at 330 nm. One of the proteins associated with the fluorescent signal was localized in secretory cells in the pharynx. The results indicate that the secretion of fluorescent proteinaceous complexes can be an important defense against UV for this dweller. Additionally, the internalization of fluorescent complexes by ovarian cancer cells and modulation of fluorescence of redox status bears important considerations for biotechnological application of mucus components as markers.

Alves, R, Rodrigues J, Ramou E, Palma S, Roque A, Gamboa H.  2022.  Classification of Volatile Compounds with Morphological Analysis of e-nose Response, Feb. Proceedings of the 15th International Joint Conference on Biomedical Engineering Systems and Technologies - BIOSIGNALS. :31–39.: Scitepress AbstractPDF

Electronic noses (e-noses) mimic human olfaction, by identifying Volatile Organic Compounds (VOCs). This
work presents a novel approach that successfully classifies 11 known VOCs using the signals generated by
sensing gels in an in-house developed e-nose. The proposed signals’ analysis methodology is based on the
generated signals’ morphology for each VOC since different sensing gels produce signals with different shapes
when exposed to the same VOC. For this study, two different gel formulations were considered, and an average
f1-score of 84% and 71% was obtained, respectively. Moreover, a standard method in time series classification
was used to compare the performances. Even though this comparison reveals that the morphological approach
is not as good as the 1-nearest neighbour with euclidean distance, it shows the possibility of using descriptive
sentences with text mining techniques to perform VOC classification.

Lenis-Rojas, {OA}, Carvalho B, Cabral R, Silva M, Friães S, Roma-Rodrigues C, Meireles {MSH }, Gomes {CSB}, Fernández {JAA }, Vila {SF }, Rubiolo {JA }, Sanchez L, Baptista {PV}, Fernandes {AR}, Royo B.  2022.  Manganese(I) tricarbonyl complexes as potential anticancer agents, feb. JBIC Journal of Biological Inorganic Chemistry. 27:49–64., Number 1: Springer Abstract

The antiproliferative activity of [Mn(CO)3(N^N)Br] (N^N = phendione 1, bipy 3) and of the two newly synthesized Mn complexes [Mn(CO)3(acridine)(phendione)]OTf (2) and [Mn(CO)3(di-triazole)Br] (4) has been evaluated by MTS against three tumor cell lines A2780 (ovarian carcinoma), HCT116 (colorectal carcinoma), HCT116doxR (colorectal carcinoma resistant to doxorubicin), and in human dermal fibroblasts. The antiproliferative assay showed a dose-dependent effect higher in complex 1 and 2 with a selectivity toward ovarian carcinoma cell line 21 times higher than in human fibroblasts. Exposure of A2780 cells to IC50 concentrations of complex 1 and 2 led to an increase of reactive oxygen species that led to the activation of cell death mechanisms, namely via intrinsic apoptosis for 2 and autophagy and extrinsic apoptosis for 1. Both complexes do not target DNA or interfere with cell cycle progression but are able to potentiate cell migration and neovascularization (for 2) an indicative that their application might be directed for initial tumor stages to avoid tumor invasion and metastization and opening a new avenue for complex 2 application in regenerative medicine. Interestingly, both complexes do not show toxicity in both in vivo models (CAM and zebrafish). Graphical abstract: [Figure not available: see fulltext.]

Nuez-Martínez, M, Queralt-Martín M, Muñoz-Juan A, Aguilella {VM }, Laromaine A, Teixidor F, Viñas C, Pinto {CG }, Pinheiro T, Guerreiro {JF }, Mendes F, Roma-Rodrigues C, Baptista {PV}, Fernandes {AR}, Valic S, Marques F.  2022.  Boron clusters (ferrabisdicarbollides) shaping the future as radiosensitizers for multimodal (chemo/radio/PBFR) therapy of glioblastoma, dec. Journal of Materials Chemistry B. 10:9794–9815., Number 47: RSC - Royal Society of Chemistry Abstract

Glioblastoma multiforme (GBM) is the most common and fatal primary brain tumor, and is highly resistant to conventional radiotherapy and chemotherapy. Therefore, the development of multidrug resistance and tumor recurrence are frequent. Given the poor survival with the current treatments, new therapeutic strategies are urgently needed. Radiotherapy (RT) is a common cancer treatment modality for GBM. However, there is still a need to improve RT efficiency, while reducing the severe side effects. Radiosensitizers can enhance the killing effect on tumor cells with less side effects on healthy tissues. Herein, we present our pioneering study on the highly stable and amphiphilic metallacarboranes, ferrabis(dicarbollides) ([o-FESAN]− and [8,8′-I2-o-FESAN]−), as potential radiosensitizers for GBM radiotherapy. We propose radiation methodologies that utilize secondary radiation emissions from iodine and iron, using ferrabis(dicarbollides) as iodine/iron donors, aiming to achieve a greater therapeutic effect than that of a conventional radiotherapy. As a proof-of-concept, we show that using 2D and 3D models of U87 cells, the cellular viability and survival were reduced using this treatment approach. We also tested for the first time the proton boron fusion reaction (PBFR) with ferrabis(dicarbollides), taking advantage of their high boron (11B) content. The results from the cellular damage response obtained suggest that proton boron fusion radiation therapy, when combined with boron-rich compounds, is a promising modality to fight against resistant tumors. Although these results are encouraging, more developments are needed to further explore ferrabis(dicarbollides) as radiosensitizers towards a positive impact on the therapeutic strategies for GBM.

Gago, D, Corvo MC, Chagas R, Ferreira LM, Coelhoso I.  2022.  Protein Adsorption Performance of a Novel Functionalized Cellulose-Based Polymer, DEC. POLYMERS. 14, Number 23 Abstract

Dicarboxymethyl cellulose (DCMC) was synthesized and tested for protein adsorption. The prepared polymer was characterized by inductively coupled plasma atomic emission spectrometry (ICP-AES), attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and solid state nuclear magnetic resonance (ssNMR) to confirm the functionalization of cellulose. This work shows that protein adsorption onto DCMC is charge dependent. The polymer adsorbs positively charged proteins, cytochrome C and lysozyme, with adsorption capacities of 851 and 571 mg g(-1), respectively. In both experiments, the adsorption process follows the Langmuir adsorption isotherm. The adsorption kinetics by DCMC is well described by the pseudo second-order model, and adsorption equilibrium was reached within 90 min. Moreover, DCMC was successfully reused for five consecutive adsorption-desorption cycles, without compromising the removal efficiency (98-99%).

Santos, MFA, Sciortino G, Correia I, Fernandes ACP, Santos-Silva T, Pisanu F, Garribba E, Pessoa JC.  2022.  Binding of VIVO2+, VIVOL, VIVOL2 and VVO2L Moieties to Proteins: X-ray/Theoretical Characterization and Biological Implications, 2022. Chemistry – A European JournalChemistry – A European Journal. 28(40):e202200105.: John Wiley & Sons, Ltd AbstractWebsite

Abstract Vanadium compounds have frequently been proposed as therapeutics, but their application has been hampered by the lack of information on the different V-containing species that may form and how these interact with blood and cell proteins, and with enzymes. Herein, we report several resolved crystal structures of lysozyme with bound VIVO2+ and VIVOL2+, where L=2,2?-bipyridine or 1,10-phenanthroline (phen), and of trypsin with VIVO(picolinato)2 and VVO2(phen)+ moieties. Computational studies complete the refinement and shed light on the relevant role of hydrophobic interactions, hydrogen bonds, and microsolvation in stabilizating the structure. Noteworthy is that the trypsin?VVO2(phen) and trypsin?VIVO(OH)(phen) adducts correspond to similar energies, thus suggesting a possible interconversion under physiological/biological conditions. The obtained data support the relevance of hydrolysis of VIV and VV complexes in the several types of binding established with proteins and the formation of different adducts that might contribute to their pharmacological action, and significantly widen our knowledge of vanadium?protein interactions.

Oliveira, AR, Mota C, Klymanska K, Biaso F, Romão MJ, Guigliarelli B, Pereira IC.  2022.  Spectroscopic and Structural Characterization of Reduced Desulfovibrio vulgaris Hildenborough W-FdhAB Reveals Stable Metal Coordination during Catalysis, 2022. ACS Chemical BiologyACS Chemical Biology. 17(7):1901-1909.: American Chemical Society AbstractWebsite

Metal-dependent formate dehydrogenases are important enzymes due to their activity of CO2 reduction to formate. The tungsten-containing FdhAB formate dehydrogenase from Desulfovibrio vulgaris Hildenborough is a good example displaying high activity, simple composition, and a notable structural and catalytic robustness. Here, we report the first spectroscopic redox characterization of FdhAB metal centers by EPR. Titration with dithionite or formate leads to reduction of three [4Fe–4S]1+ clusters, and full reduction requires Ti(III)–citrate. The redox potentials of the four [4Fe–4S]1+ centers range between −250 and −530 mV. Two distinct WV signals were detected, WDV and WFV, which differ in only the g2-value. This difference can be explained by small variations in the twist angle of the two pyranopterins, as determined through DFT calculations of model compounds. The redox potential of WVI/V was determined to be −370 mV when reduced by dithionite and −340 mV when reduced by formate. The crystal structure of dithionite-reduced FdhAB was determined at high resolution (1.5 Å), revealing the same structural alterations as reported for the formate-reduced structure. These results corroborate a stable six-ligand W coordination in the catalytic intermediate WV state of FdhAB.Metal-dependent formate dehydrogenases are important enzymes due to their activity of CO2 reduction to formate. The tungsten-containing FdhAB formate dehydrogenase from Desulfovibrio vulgaris Hildenborough is a good example displaying high activity, simple composition, and a notable structural and catalytic robustness. Here, we report the first spectroscopic redox characterization of FdhAB metal centers by EPR. Titration with dithionite or formate leads to reduction of three [4Fe–4S]1+ clusters, and full reduction requires Ti(III)–citrate. The redox potentials of the four [4Fe–4S]1+ centers range between −250 and −530 mV. Two distinct WV signals were detected, WDV and WFV, which differ in only the g2-value. This difference can be explained by small variations in the twist angle of the two pyranopterins, as determined through DFT calculations of model compounds. The redox potential of WVI/V was determined to be −370 mV when reduced by dithionite and −340 mV when reduced by formate. The crystal structure of dithionite-reduced FdhAB was determined at high resolution (1.5 Å), revealing the same structural alterations as reported for the formate-reduced structure. These results corroborate a stable six-ligand W coordination in the catalytic intermediate WV state of FdhAB.

Santos, AFM, Cruz C, Godinho MH, Dionísio M, Figueirinhas JL, Branco LC.  2022.  Synthesis and characterisation of ionic liquid crystals based on substituted pyridinium cations, 2022. Liquid CrystalsLiquid Crystals. :1-13.: Taylor & Francis AbstractWebsite
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Faria, J, Dionísio B, Soares I, Baptista AC, Marques A, Gonçalves L, Bettencourt A, Baleizão C, Ferreira I.  2022.  Cellulose acetate fibres loaded with daptomycin for metal implant coatings. Carbohydrate Polymers. 276:118733.
da Rosa, RR, Silva PES, Saraiva DV, Kumar A, de Sousa AMP, Sebastião P, Fernandes SN, Godinho MH.  2022.  Cellulose Nanocrystal Aqueous Colloidal Suspensions: Evidence of Density Inversion at the Isotropic-liquid Crystal Phase Transition. Advanced Materials. n/a:2108227., Number n/a AbstractWebsite

Abstract The colloidal suspensions of aqueous cellulose nanocrystals (CNCs) are known to form liquid crystalline systems above certain critical concentrations. From an isotropic phase; tactoid formation; growth; and sedimentation have been determined as the genesis of a high-density cholesteric phase; which after drying; originates solid iridescent films. Herein; we report the coexistence of a liquid crystal upper phase and an isotropic bottom phase in CNC aqueous suspensions at isotropic-nematic phase separation for the first time. Furthermore; isotropic spindle-like domains are observed in the low-density liquid crystalline phase; and high-density liquid crystalline phases are also prepared. The CNCs isolated from the low- and high-density liquid crystalline phases are found to have similar average lengths; diameters; and surface charges. The existence of a liquid crystalline low-density phase is explained by the presence of air dissolved in the water present within the CNCs. The air dissolves out when the water solidifies into ice and remains within the CNCs. The self-adjustment of the cellulose chain conformation enables the entrapment of air within the CNCs and CNC buoyancy in aqueous suspensions. This article is protected by copyright. All rights reserved

Shlapa, Y, Solopan S, Sarnatskaya V, Siposova K, Garcarova I, Veltruska K, Timashkov I, Lykhova O, Kolesnik D, Musatov A, Nikolaev V, Belous A.  2022.  Cerium dioxide nanoparticles synthesized via precipitation at constant pH: Synthesis, physical-chemical and antioxidant properties. Colloids and Surfaces B: Biointerface. 220(112960 )
Siposova, K, Huntosova V, Garcarova I, Shlapa Y, Timashkov I, Belous A, Musatov A.  2022.  Dual-Functional Antioxidant and Anti-amyloid Cerium Oxide Nanoparticles Fabricated by Controlled Synthesis in Water-Alcohol Solutions. Biomedicines. 10(942)
Karpets, M, Rajnak M, Petrenko VI, Gapon I, Avdeev M, Bulavin L, Timko M, Kopcansky P.  2022.  Electric field-induced assembly of magnetic nanoparticles from dielectric ferrofluids on planar interface. Journal of Molecular Liquids. 362(119773)
Gonçalves, SP.  2022.  From cellulose-based waste to advanced materials. FCT Nova.
Siposova, K, Petrenko VI, Garcarova I, Sedlakova D, Almasy L, Kyzyma OA, Kriechbaum M, Musatov A.  2022.  The intriguing dose-dependent effect of selected amphiphilic compounds on insulin amyloid aggregation: Focus on a cholesterol-based detergent. Chobimalt. 9(955282)
Pauleta, SR, Carepo M, Grazina R, Moura I, Moura JJG.  2022.  Iron-Sulfur centers: Functions of an ancient metal site. Comprehensive Inorganic Chemistry III From Biology to Nanotechnology, vol. 2. (Vincent Pecoraro and Zijian Guo, Ed.).:???., ???: ???
Ramos, A, Isufi B, Marreiros R, Bolesova M, Gajdsova K.  2022.  Rational Use of FPFRC in Slab-Connections Under Reversed Horizontal Cyclic Loading. Engineering Structures. Accepted for publication Abstract

Slab – column connections that are subjected to combined gravity and horizontal loading during an earthquake are prone to premature failure due to punching shear. Traditional solutions to avoid punching failure and to increase the displacement capacity of this type of connection include using stirrups and double-headed studs as shear reinforcement. The use of High-Performance Fiber Reinforced Concrete (HPFRC) in a small region of the slab around the column as a substitute for traditional solutions is investigated in this paper, because this material has the potential to reduce labor and material costs. To fulfill this objective, four slab specimens with a thickness of 150 mm were tested under combined gravity and reversed horizontal drifts. The results are discussed in detail. The experimental variables considered were the top flexural reinforcement ratio, the size of the HPFRC zone and the intensity of the gravity load. Previously published tests that serve as reference specimens are used to compare the results. The behavior of the specimens with HPFRC was substantially improved compared to the reference specimens in terms of drift capacity: from only 1.0% drift to above 5.5%, even though a very small quantity of HPFRC was used, extended up to only 1.5 times the effective depth of the slab from the face of the column. Specimens with HPFRC also behaved better when compared to specimens with High-Strength Concrete (HSC). Side effects of using HPFRC in the slab in the vicinity of the column include an increase of the unbalanced moment transfer capacity and lateral stiffness, as well as a reduction of the deflections of the slab.

Karamash, M, Stumpe M, Dengjel J, Salgueiro CA, Giese B, Fromm KM.  2022.  Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates. Frontiers in Microbiology. 13 AbstractWebsite

Geobacter sulfurreducens is a widely applied microorganism for the reduction of toxic metal salts, as an electron source for bioelectrochemical devices, and as a reagent for the synthesis of nanoparticles. In order to understand the influence of metal salts, and of electron transporting, multiheme c-cytochromes on the electron flux during respiration of G. sulfurreducens, the reduction kinetic of Fe3+, Co3+, V5+, Cr6+, and Mn7+ containing complexes were measured. Starting from the resting phase, each G. sulfurreducens cell produced an electron flux of 3.7 × 105 electrons per second during the respiration process. Reduction rates were within ± 30% the same for the 6 different metal salts, and reaction kinetics were of zero order. Decrease of c-cytochrome concentrations by downregulation and mutation demonstrated that c-cytochromes stabilized respiration rates by variation of their redox states. Increasing Fe2+/heme levels increased electron flux rates, and induced respiration flexibility. The kinetic effects parallel electrochemical results of G. sulfurreducens biofilms on electrodes, and might help to optimize bioelectrochemical devices.

M.J., N, G.N. V, A. S‐A, J.J.G. M, C. R, Sousa JP, C.M. C.  2022.  Screen‐Printed Electrodes Testing for Detection of Potential Stress Biomarkers in Sweat. Electrocatalysis. 13:299–305.
Gonçalves, AM, Sousa Â, Pedro AQ, Romão MJ, Queiroz JA, Gallardo E, Passarinha LA.  2022.  Advances in Membrane-Bound Catechol-O-Methyltransferase Stability Achieved Using a New Ionic Liquid-Based Storage Formulation. International Journal of Molecular Sciences. 23, Number 13 AbstractWebsite

Membrane-bound catechol-O-methyltransferase (MBCOMT), present in the brain and involved in the main pathway of the catechol neurotransmitter deactivation, is linked to several types of human dementia, which are relevant pharmacological targets for new potent and nontoxic inhibitors that have been developed, particularly for Parkinson’s disease treatment. However, the inexistence of an MBCOMT 3D-structure presents a blockage in new drugs’ design and clinical studies due to its instability. The enzyme has a clear tendency to lose its biological activity in a short period of time. To avoid the enzyme sequestering into a non-native state during the downstream processing, a multi-component buffer plays a major role, with the addition of additives such as cysteine, glycerol, and trehalose showing promising results towards minimizing hMBCOMT damage and enhancing its stability. In addition, ionic liquids, due to their virtually unlimited choices for cation/anion paring, are potential protein stabilizers for the process and storage buffers. Screening experiments were designed to evaluate the effect of distinct cation/anion ILs interaction in hMBCOMT enzymatic activity. The ionic liquids: choline glutamate [Ch][Glu], choline dihydrogen phosphate ([Ch][DHP]), choline chloride ([Ch]Cl), 1- dodecyl-3-methylimidazolium chloride ([C12mim]Cl), and 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) were supplemented to hMBCOMT lysates in a concentration from 5 to 500 mM. A major potential stabilizing effect was obtained using [Ch][DHP] (10 and 50 mM). From the DoE 146% of hMBCOMT activity recovery was obtained with [Ch][DHP] optimal conditions (7.5 mM) at −80 °C during 32.4 h. These results are of crucial importance for further drug development once the enzyme can be stabilized for longer periods of time.

Pinto, F, Lourenço AF, Pedrosa JFS, Gonçalves L, Ventura C, Vital N, Bettencourt A, Fernandes SN, da Rosa RR, Godinho MH, Louro H, Ferreira PJT, Silva MJ.  2022.  Analysis of the In Vitro Toxicity of Nanocelluloses in Human Lung Cells as Compared to Multi-Walled Carbon Nanotubes. Nanomaterials. 12, Number 9 AbstractWebsite

Cellulose micro/nanomaterials (CMNM), comprising cellulose microfibrils (CMF), nanofibrils (CNF), and nanocrystals (CNC), are being recognized as promising bio-nanomaterials due to their natural and renewable source, attractive properties, and potential for applications with industrial and economical value. Thus, it is crucial to investigate their potential toxicity before starting their production at a larger scale. The present study aimed at evaluating the cell internalization and in vitro cytotoxicity and genotoxicity of CMNM as compared to two multi-walled carbon nanotubes (MWCNT), NM-401 and NM-402, in A549 cells. The exposure to all studied NM, with the exception of CNC, resulted in evident cellular uptake, as analyzed by transmission electron microscopy. However, none of the CMNM induced cytotoxic effects, in contrast to the cytotoxicity observed for the MWCNT. Furthermore, no genotoxicity was observed for CNF, CNC, and NM-402 (cytokinesis-block micronucleus assay), while CMF and NM-401 were able to significantly raise micronucleus frequency. Only NM-402 was able to induce ROS formation, although it did not induce micronuclei. Thus, it is unlikely that the observed CMF and NM-401 genotoxicity is mediated by oxidative DNA damage. More studies targeting other genotoxicity endpoints and cellular and molecular events are underway to allow for a more comprehensive safety assessment of these nanocelluloses.

Morais, {TS }, Fernandes {AR}, Baptista {PV}, Gambino D.  2022.  Editorial: Rational drug design of metal complexes for cancer therapy. Frontiers in Chemistry. 10: Frontiers Media Abstract
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Ventura, C, Marques C, Cadete J, Vilar M, Pedrosa JFS, Pinto F, Fernandes SN, da Rosa RR, Godinho MH, Ferreira PJT, Louro H, Silva MJ.  2022.  Genotoxicity of Three Micro/Nanocelluloses with Different Physicochemical Characteristics in MG-63 and V79 Cells. Journal of Xenobiotics. 12:91–108., Number 2 AbstractWebsite

(1) Background: Nanocellulose is an innovative engineered nanomaterial with an enormous potential for use in a wide array of industrial and biomedical applications and with fast growing economic value. The expanding production of nanocellulose is leading to an increased human exposure, raising concerns about their potential health effects. This study was aimed at assessing the potential toxic and genotoxic effects of different nanocelluloses in two mammalian cell lines; (2) Methods: Two micro/nanocelluloses, produced with a TEMPO oxidation pre-treatment (CNFs) and an enzymatic pre-treatment (CMFs), and cellulose nanocrystals (CNCs) were tested in osteoblastic-like human cells (MG-63) and Chinese hamster lung fibroblasts (V79) using the MTT and clonogenic assays to analyse cytotoxicity, and the micronucleus assay to test genotoxicity; (3) Results: cytotoxicity was observed by the clonogenic assay in V79 cells, particularly for CNCs, but not by the MTT assay; CNF induced micronuclei in both cell lines and nucleoplasmic bridges in MG-63 cells; CMF and CNC induced micronuclei and nucleoplasmic bridges in MG-63 cells, but not in V79 cells; (4) Conclusions: All nanocelluloses revealed cytotoxicity and genotoxicity, although at different concentrations, that may be related to their physicochemical differences and availability for cell uptake, and to differences in the DNA damage response of the cell model.

2021
Gago, D, Chagas R, Ferreira LM.  2021.  The Effect of Dicarboxymethyl Cellulose on the Prevention of Protein Haze Formation on White Wine, SEP. BEVERAGES. 7, Number 3 Abstract
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Saracino, F, Brinco J, Gago D, Gomes da Silva M, Ferreira RB, Ricardo-da-Silva J, Chagas R, Ferreira LM.  2021.  DCMC as a Promising Alternative to Bentonite in White Wine Stabilization. Impact on Protein Stability and Wine Aromatic Fraction, OCT. MOLECULES. 26, Number 20 Abstract
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