-
Molecules (Basel, Switzerland) Nov 2023Ionic liquids have been the subject of intense research because of their unique electrochemical properties and potential applications in various fields. In this article,...
Electrical Conductivity of Ionic Liquids 1-Hexyl-3-Methylimidazolium Chloride (HMIM) and 1-Methyl-3-Octylimidazolium Chloride (OMIM) in Mixtures with Selected Alkoxy Alcohols over a Wide Temperature Range.
Ionic liquids have been the subject of intense research because of their unique electrochemical properties and potential applications in various fields. In this article, we analyze the electrical conductivity of two selected ionic liquids, 1-hexyl-3-methylimidazolium chloride (HMIM) and 1-eethyl-3-octylimidazolium chloride (OMIM), in various alkoxy alcohols such as 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol and 2-butoxyethanol. Our research focuses on attempting to analyze the impact of the molecular structure of both the ionic liquids and alkoxy alcohols on their electrical conductivity properties. The results of our study can be highly beneficial in the design of advanced electrochemical materials and their various applications.
PubMed: 38067560
DOI: 10.3390/molecules28237831 -
International Journal of Biological... Dec 2023In this work, kraft lignin (KL) was polymerized with vinylbenzyl chloride (VBC) in a molar ratio of 1.8:1 (KL: VBC) using sodium persulfate (NaSO) as an initiator at...
In this work, kraft lignin (KL) was polymerized with vinylbenzyl chloride (VBC) in a molar ratio of 1.8:1 (KL: VBC) using sodium persulfate (NaSO) as an initiator at pH 9-10 and temperature of 80-90 °C for 3 h to produce polymer kraft lignin-g-poly(4-vinylbenzyl chloride) KL-poly(VBC) 1. Then, the grafting reaction was conducted with two different imidazole-based monomers of different side-chain lengths (methyl and n-butyl), namely, 1-methylimidazole (MIM), 1-n-butylimidazole (BIM), which led to the formation of novel polymers, kraft lignin-g-poly(4-vinylbenzyl-1-methylimidazolium chloride) KL-poly(VBC-MIM) 2a and kraft lignin-g-poly(4-vinylbenzyl-1-n-butyl imidazolium chloride) KL-poly(VBC-BIM) 2b. The polymer 2a generated a larger molecular weight polymer with a higher charge density and solubility than polymer 2b since the n-butyl group would cause steric hindrance and weaker monomer to react with intermediate polymer 1 in the second stage. The contact angle analysis confirmed more hydrophilicity of polymer 2a, and elemental analysis confirmed the more successful polymerization of polymer 2a. Applying the generated polymers as flocculants for a kaolin suspension confirmed that polymer 2a had similar performance with commercial cationic polyacrylamide (CPAM) flocculants, even though polymer 2a had a smaller molecular weight. This polymerization offers a promising pathway for generating cationic polymers with excellent performance as a flocculant for suspensions.
Topics: Polymers; Chlorides; Lignin; Molecular Weight; Solvents
PubMed: 37595716
DOI: 10.1016/j.ijbiomac.2023.126382 -
Biomacromolecules Oct 2023Due to increasing public concern over hygiene, there have been many studies investigating antimicrobial and antiviral agents recently. With the aim of developing...
Due to increasing public concern over hygiene, there have been many studies investigating antimicrobial and antiviral agents recently. With the aim of developing biobased virucidal/virus capture agents, we report a chemical modification of the cellulose nanocrystals (CNCs) surface with poly(2-dimethylamino) ethyl acrylate) methyl chloride quaternary salt (Q-PDMAEA) to introduce the positively charged functional groups. The surface of CNCs was modified through direct and indirect graft polymerization. Subsequently, the direct and indirect cationization effect on the degree of functionalization, thermal stability, crystallinity, and antiviral activity of CNCs was investigated. Indirect cationization produced the highest degree of polymer grafting, increasing particle size and thermal stability. Further, the modified CNCs were tested for their ability to capture nonenveloped bacteriophages PhiX174 (ΦX174) and MS2. We observed a significant (>4.19 log) reduction in total viral load by specific functionalized CNCs. However, the activity depended on the structure of functional groups, surface charge density, and the type of virus under study. Overall, the direct and indirect cationization of CNC leads to biobased agents with immobilized cationic charge, with good virus capture activity. Such agents can be used for various applications including textiles, packaging, wastewater treatment, etc.
PubMed: 36464847
DOI: 10.1021/acs.biomac.2c01045 -
Carbohydrate Polymers Nov 2023Gel materials with tailored functions and tissue-like properties have gained significant interest in emerging applications, including tissue engineering scaffolds,...
Gel materials with tailored functions and tissue-like properties have gained significant interest in emerging applications, including tissue engineering scaffolds, flexible electronics, and soft robotics. In this work, we developed a stretchable, flexible, adhesive, and conductive organohydrogel through physical cross-linking of the poly (N-[tris (hydroxymethyl) methyl] acrylamide-co-acrylamide) (denoted as P(THMA-AM)) network in the presence of cellulose nanofiber (CNF), sodium chloride, and glycerol. The gel matrix is rich in intermolecular interactions, including hydrogen bonding and ionic interactions, which contribute to a highly compact and cohesive structure without the requirement of any chemical crosslinkers. Moreover, the plasticizing effect of glycerol can mitigate the self-entanglement of CNFs, enhancing their mobility and ultimately conferring the organohydrogel with exceptional stretchability and flexibility. The resulting organohydrogel exhibited superior mechanical properties, self-adhesion, and ionic conductivity, making it an excellent candidate for strain-sensing applications, particularly in distinguishing and monitoring human movements.
PubMed: 37659812
DOI: 10.1016/j.carbpol.2023.121211 -
Food Research International (Ottawa,... Nov 2023The aim of this study was the chemical, microbiological, textural, and sensory characterization of pilot-scale prototypes of an Italian ewe's raw milk cheese...
Chemical, microbiological, textural, and sensory characteristics of pilot-scale Caciofiore cheese curdled with commercial Cynara cardunculus rennet and crude extracts from spontaneous and cultivated Onopordum tauricum.
The aim of this study was the chemical, microbiological, textural, and sensory characterization of pilot-scale prototypes of an Italian ewe's raw milk cheese (Caciofiore) curdled with commercial Cynara cardunculus rennet, used as a control, and crude extracts obtained from flowers of either spontaneous or cultivated Onopordum tauricum. Hence, the control and experimental cheese prototypes produced in two rounds of cheesemaking trials were assayed, at the end of their 60-day maturation, for the following features: pH, titratable acidity, dry matter, fat, total and soluble nitrogen (TN and SN, respectively), ash, salt, protein, lactose, viable plate counts and composition of the bacterial and fungal populations, color, texture, volatile organic compounds (VOCs), and olfactory attributes by sensory analysis (the latter for the sole prototypes curdled with the commercial rennet and the extract obtained from cultivated O. tauricum). The data overall collected showed a very low impact of the type of thistle rennet on the analyzed cheese traits, with significant differences being exclusively found for SN/TN%, titratable acidity, color, and adhesiveness. By contrast, a higher impact of the cheesemaking round was seen, with significant differences being observed for salt content, load of presumptive lactobacilli, thermophilic cocci, and Escherichia coli, and levels of the following VOCs: 2,3-butanedione, 2-pentanone, 1-butanol, 2-heptanone, 3-methyl-1-butanol, 2-heptanol, 2-nonanone, dimethyl trisulfide, 2-methyl propanoic acid, butanoic acid, and 3-methyl butanoic acid. Sensory analysis revealed a strong ewe's cheese odor, accompanied by other olfactory notes, such as pungent, sour curd, sweet, and Parmesan cheese-like notes, in all the analysed cheese prototypes. Moreover, key odor active compounds, including butanoic acid, ethyl butanoate, 2,3-butanedione, 1-octen-3-one, and dimethyl trisulfide, were identified by GC-olfactometry analysis. Regarding the odor attributes as determined by sensory analysis, again the type of rennet had an almost negligible impact, with significant differences being only perceived for 1 or 2 out of 20 odor attributes, depending on the analytical conditions applied. Although some aspects deserve further investigation, the results herein collected confirm that O. tauricum can be regarded as an alternative source of thistle rennet for the manufacture of Caciofiore cheese, and more in general, Mediterranean ewe's milk cheeses.
Topics: Sheep; Animals; Female; Cynara; Onopordum; Cheese; Butyric Acid; Diacetyl; Sodium Chloride, Dietary; Complex Mixtures
PubMed: 37803784
DOI: 10.1016/j.foodres.2023.113459 -
ACS Omega Sep 2023We reinvestigated the reported method for the synthesis of ethyl 3-[5-(2-ethoxycarbonyl-1-methylvinyloxy)-1-methyl-1-indol-3-yl]-but-2-enoate (MIBE), which was obtained...
We reinvestigated the reported method for the synthesis of ethyl 3-[5-(2-ethoxycarbonyl-1-methylvinyloxy)-1-methyl-1-indol-3-yl]-but-2-enoate (MIBE), which was obtained by the reaction of 5-hydroxy-1-methyl-1-indole with excess ethyl acetoacetate catalyzed by indium(III) chloride. Based on the NMR and MS data, we assigned the structure of the isolated product as (3)-3-(2-ethoxy-2-oxoethylidene)-1,2,3,4-tetrahydro-7-hydroxy-1,4-dimethylcyclopent[]indole-1-acetate rather than the reported MIBE.
PubMed: 37692243
DOI: 10.1021/acsomega.3c03686 -
The Journal of Physical Chemistry. A Apr 2024The microsolvated anions HO(NH) were found to induce new nucleophile NH(HO)(NH) via intramolecular proton transfer. Hence, the ion-molecule nucleophilic substitution...
The microsolvated anions HO(NH) were found to induce new nucleophile NH(HO)(NH) via intramolecular proton transfer. Hence, the ion-molecule nucleophilic substitution (S2) reaction between CHCl and these shapeshifting nucleophiles lead to both the HO path and NH path, meaning that the respective attacking nucleophile is HO or NH. The CCSD(T) level of calculation was performed to characterize the potential energy surfaces. Calculations indicate that the HO species are lower in energy than the NH species, and the S2 reaction barriers are lower for the HO path than the NH-path. Incremental solvation increases the barrier for both paths. Comparison between HO(NH) and HOO(NH) confirmed the existence of an α-effect under microsolvated conditions. Comparison between HO(NH) and HO(HO) indicated that the more polarized HO stabilizes the nucleophiles more than NH, and thus, the hydrated systems have higher S2 reaction barriers. The aforementioned barrier changes can be explained by the differential stabilization of the nucleophile and HOMO levels upon solvation, thus affecting the HOMO-LUMO interaction between the nucleophile and substrate. For the same kind of nucleophilic attacking atom, O or N, the reaction barrier has a good linear correlation with the HOMO level of the nucleophiles. Hence, the HOMO level or the binding energy of microsolvated nucleophiles is a good indicator to evaluate the order of barrier heights. This work expands our understanding of the microsolvation effect on prototype S2 reactions beyond the water solvent.
PubMed: 38530765
DOI: 10.1021/acs.jpca.3c07553 -
Biomimetics (Basel, Switzerland) Jul 2023Novel imidazole derivatives of the low molecular weight chitosan N-(2-hydroxypropyl)-1H-1,2,3-triazol-4-yl)methyl)-1-methyl-1H-imidazol-3-ium chitosan chloride (NMIC)...
Novel imidazole derivatives of the low molecular weight chitosan N-(2-hydroxypropyl)-1H-1,2,3-triazol-4-yl)methyl)-1-methyl-1H-imidazol-3-ium chitosan chloride (NMIC) were synthesized using copper-catalyzed azide-alkyne cycloaddition (CuAAC). The degrees of substitution (DSs) for the new derivatives were 18-76%. All chitosan derivatives (2000 µg/mL) were completely soluble in water. The antimicrobial activity of the new compounds against and was studied. The effect of chitosan derivatives on blood and its components was studied. NMIC samples (DS 34-76%) at a concentration <10 μg/mL had no effect on blood and plasma coagulation. Chitosan derivatives (DS 18-76%) at concentrations of ≥83 μg/mL in blood and ≥116.3 μg/mL in plasma resulted in a prolongation of the clotting time of blood and plasma, positively related to the DS. At concentrations up to 9.1 μg/mL, NMIC did not independently provoke platelet aggregation. The degree of erythrocyte hemolysis upon contact with NMIC samples (2.5-2500 μg/mL) was below 4%. The inhibition of blood/plasma coagulation indicates the promising use of the studied samples to modify the surface of medical materials in order to achieve thromboresistance.
PubMed: 37504190
DOI: 10.3390/biomimetics8030302 -
International Journal of Systematic and... Oct 2023Two aerobic, Gram-stain-positive, spore-forming motile bacterial strains, designated SSPM10-3 and SSWR10-1, were isolated from salterns in Jeollanam province of South...
Two aerobic, Gram-stain-positive, spore-forming motile bacterial strains, designated SSPM10-3 and SSWR10-1, were isolated from salterns in Jeollanam province of South Korea. Both strains were halotolerant and grew well in 5 % NaCl but not in 20 and 25% NaCl, respectively. Optimal growth was observed with 5 % NaCl, at 30 °C and at pH 7.0-8.0. On the basis of the results of phylogenetic analysis using 16S rRNA gene sequence, both the strains were placed within the genus with (98.65 % similarity) as their nearest neighbour. Menaquinone-7 (MK-7) (97 %) was the major isoprenoid quinone in both strains and major cellular fatty acids were anteiso-C, iso-C and anteiso-C. Orthologous average nucleotide identity with usearch (OrthoANIu) and digital DNA-DNA hybridisation (dDDH) percentage comparison indicated that SSPM10-3 and SSWR10-1 exhibited highest similarity with Awa-1 at 74.27 % and 21.0 and 74.23 % and 20.0 %, respectively. The DNA G+C contents of the strains were 39.1 % (SSPM10-3) and 38.5 % (SSWR10-1). Members of the genus , both strains were distinct from each other with respect to their ability to produce urease, β-glucosidase, assimilation of inulin and methyl-α-d-glucopyranoside and degradation of casein. Compared with each other, ANI and d4 dDDH calculations were only 88.2 % and 36.3 %, well below the cut-off values for species delineation for each index. On the basis of their phenotypic, physiological, biochemical and phylogenetic characteristics,SSPM10-3 and SSWR10-1 represent distinct novel species for which names SSPM10-3 and SSWR10-1 are proposed. The type strains are SSPM10-3 (=KACC 21933 =NBRC 115502) and SSWR10-1 (=KACC 21934 =NBRC 115503).
Topics: Fatty Acids; Phylogeny; RNA, Ribosomal, 16S; Sodium Chloride; Bacterial Typing Techniques; DNA, Bacterial; Base Composition; Sequence Analysis, DNA; Vitamin K 2; Phospholipids
PubMed: 37787383
DOI: 10.1099/ijsem.0.005965 -
ACS Omega Oct 2023The effect of the ionic liquids (ILs) 1-methyl-3-tetradecylimidazolium chloride ([CMIM][Cl]), 1-dodecyl-3-methylimidazolium chloride ([CMIM][Cl]), and...
The effect of the ionic liquids (ILs) 1-methyl-3-tetradecylimidazolium chloride ([CMIM][Cl]), 1-dodecyl-3-methylimidazolium chloride ([CMIM][Cl]), and 1-decyl-methylimidazolium chloride ([CMIM][Cl]) on the structure of bovine serum albumin (BSA) was investigated by fluorescence spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, small-angle X-ray scattering (SAXS), and molecular dynamics (MD) simulations. Concerning the fluorescence measurements, we observed a blue shift and a fluorescence quenching as the IL concentration increased in the solution. Such behavior was observed for all three studied imidazolium-based ILs, being larger as the number of methylene groups in the alkyl chain increased. UV-vis absorbance measurements indicate that even at relatively small IL/protein ratios, like 1:1 or 1:2, ([CMIM][Cl]) is able to change, at least partially, the sample turbidity. SAXS results agree with the spectroscopic techniques and suggest that the proteins underwent partial unfolding, evidenced by an increase in the radius of gyration () of the scattering particle. In the absence and presence of ([CMIM][Cl]) = 3 mM BSA increases from 29.1 to 45.1 Å, respectively. Together, these results indicate that the interaction of BSA with ILs is divided into three stages: the first stage is characterized by the protein in its native form. It takes place for protein/IL ≤ 1:2, and the interaction is predominantly due to the electrostatic forces provided by the negative charges on the surface of BSA and the cationic polar head of the ILs. In the second stage, higher IL concentrations induce the unfolding of the protein, most likely inducing the unfolding of domains I and III, in such a way that the protein's secondary structure is kept almost unaltered. In the last stage, IL micelles start to form, and therefore, the interaction with protein reaches a saturation point and free micelles may be formed. We believe that this work provides new information about the interaction of ILs with BSA.
PubMed: 37867681
DOI: 10.1021/acsomega.3c04188