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This study investigates a series of surface-active ionic liquids (SAILs), including both imidazolium monocationic and dicationic compounds. These compounds are promising candidates, as they combine unique surface properties with antimicrobial activity, aligning with modern trends in chemistry. The research encompasses synthesis, thermal analysis, and topographical assessment, focusing on the impact of the amphiphilic cationic moiety, alkyl chain length, and the spatial relationship between the imidazolium ring and the phenyl substituent on the compounds' physicochemical behavior. An added value of this work lies in the integration of theoretical calculations related to their behavior in solution and at the air–water interface, revealing spontaneous adsorption (negative Gibbs free energy of adsorption values, ΔG0ads). The results indicate that dicationic imidazolium SAILs have a greater tendency to form micelles but are less effective at reducing surface tension compared to their monocationic counterparts. Topography analyses of SAILs with 12 carbon atoms further highlight these differences. Notably, the dicationic SAIL with 12 carbon atoms in the spacer exhibited an impressive MIC of 0.007 mmol L−1 against Candida albicans, consistent with findings showing that dicationic SAILs outperformed conventional antifungal agents, such as amphotericin B and fluconazole, at equivalent concentrations. Overall, the synthesized SAILs demonstrate superior surface activity compared to commercial surfactants and show potential as disinfectant agents. [ABSTRACT FROM AUTHOR]

The present work provides new evidence of the ongoing potential of surface-active ionic liquids (SAILs) and surface-active quaternary ammonium salts (surface-active QASs). To achieve this, a series of compounds were synthesized with a yield of ≥85%, and their thermal analyses were studied. Additionally, antimicrobial activity against both human pathogenic and soil microorganisms was investigated. Subsequently, their surface properties were explored with the aim of utilizing SAILs and surface-active QASs as alternatives to commercial amphiphilic compounds. Finally, we analyzed the wettability of the leaves' surface of plants occurring in agricultural fields at different temperatures (from 5 to 25 °C) and the model plant membrane of leaves. Our results show that the synthesized compounds exhibit higher activity than their commercial analogues such as, i.e., didecyldimethylammonium chloride (DDAC) and dodecyltrimethylammonium bromide (C12TAB), for which the CMC values are 2 mM and 15 mM. The effectiveness of the antimicrobial properties of synthesized compounds relies on their hydrophobic nature accompanied by a cut-off effect. Moreover, the best wettability of the leaves' surface was observed at 25 °C. Our research has yielded valuable insights into the potential effectiveness of SAILs and surface-active QASs as versatile compounds, offering a promising alternative to established antimicrobials and crop protection agents, all the while preserving substantial surface activity. [ABSTRACT FROM AUTHOR]

Currently composites play an important role in all aspects of engineering and technology, with constantly growing applications. Recently, more attention was focused on natural fillers due to their suitability as reinforcement materials in thermo-plastic matrices which improve the mechanical properties of these polymers. Biofillers are used due to their low cost, high strength rigidity, non-toxicity, biodegradability, and availability. Currently, spent coffee grounds (SCG) are attracting more attention as a natural filler since high amounts of SCG are generated every day (food waste of coffee processing). This study allowed us to determine the long-term effect of activated sludge microorganisms with known technical and technological parameters on the mechanical properties of composites with spent coffee grounds filler. The fittings consisted of high-density poly-ethylene (PE-HD), which was used as the matrix, and a filler based on spent coffee grounds (SCG), which was used as a modifier. It was established that the composition of the composite and its residence time in the bioreactor directly influenced the contact angle value. The shift of the contact angle value is associated with the formation of the biofilm on the tested materials. An increase in the contact angle was observed in the case of all samples tested in the bioreactor, with the lowest values equal to approx. 76.4° for sample A (PE-HD) and higher values of approx. 90° for the remaining composite samples with a coffee grounds filler. The research confirmed that the increased ratio of coffee grounds in the composite results in the increased diversity and abundance of microorganisms. The highest number and the greatest diversity of microorganisms were observed in the case of the composite with 40% coffee grounds after more than a year of exposure in the bioreactor, while the composite with 30% SCG was second. Ciliates (Ciliata), especially the sessile forms belonging to the Epistylis genus, were the most common and the most numerous group of microorganisms in the activated sludge and in the biofilm observed on the samples after immersion in the bioreactor. The conducted research confirms that the use of polymer composite mouldings with a filler in the form of spent coffee grounds as a carrier allows the efficient increase in the population of microorganisms in the bioreactor. [ABSTRACT FROM AUTHOR]

In this study, a series of 10 novel 1-methyl-3-octyloxymethylimidazolium derivatives carrying various anionic moieties (4-hydroxybenzenesulfonate, benzenesulfonate, carvacroloxyacetate, chloride, formate, propionate, thymoloxyacetate, vanillinoxyacetate, eugenoloxyacetate and trimethylacetate) were synthesized. Compounds were tested for their antimicrobial activity against six microbe strains (Staph-ylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Enterococcus faecalis, and Candida albicans), cytotoxic activity against the mouse melanoma cell line (B16 F10), and surface active properties. All synthesized compounds exhibited antimicrobial activity (expressed as minimum inhibitory concentration; in range of 0.10–27.82 mM/L), especially against Gram-positive bacteria and fungi. In addition, all compounds demonstrated cytotoxicity on B16 F10 cells (IC50 values 0.0101–0.0197 mM/L). Surface properties defined as CMC values, ranged from 0.72 to 32.35 mmol L-1. The obtained results provide an insight into the promising activity of a novel group of quaternary imidazolium derivatives having ionic liquid properties. The most potent compounds, containing a thymoloxyacetate and eugenoloxyacetate moiety, could be candidates for new antimicrobial agents or surfactants. [ABSTRACT FROM AUTHOR]

Natural auxins are a group of plant hormones that affect plant growth and development. The most common auxin is indole‐3‐acetic acid (IAA), which is mainly synthesized from tryptophan. Since converting synthetic auxins into an ionic liquid increases their herbicidal activity, an attempt was made to synthesize new amino acid ionic liquids (AAILs) with l‐tryptophanate anions. As a result of the synthesis, two homologous series, tetraalkylammonium l‐tryptophanates and dialkyldimethylammonium l‐tryptophanates, were obtained with yields exceeding 95 %. For the obtained AAILs, basic physicochemical properties (solubility in solvents of different polarity, thermal stability, phase changes, and surface activity) were determined, and whether the obtained salts act as growth stimulants for lettuce (Lactuca sativa L.) was evaluated. The transformation of l‐tryptophan into AAILs improved the physicochemical properties and increased the auxin activity. In addition, the higher content of nutrients (micro‐ and macroelements) made lettuce a healthier food product. [ABSTRACT FROM AUTHOR]

A new group of bioinspired ionic liquids (ILs) based on glycine betaine and natural or synthetic anions was synthesized. The developed synthesis methods enabled the preparation of designed salts with high yields. The melting points for 17 of the 21 betaine-based salts were below 100 °C, allowing them to be classified as ionic liquids. Moreover, the solubilities of the novel salts in water and organic solvents of different polarities were examined, and their surface activity was determined. In the greenhouse experiment, all ILs were used as pesticide adjuvants, and their impact on the herbicidal activity of iodosulfuron-methyl was determined. Additionally, the effects of the obtained salts on the deterrent properties towards pests as well as on toxicity to microorganisms and plants were determined. It turned out that most of the ILs were weak feeding deterrents; however, their toxicity to the examined organisms was relatively low. The conclusion is that some of the presented salts are high-quality pesticide adjuvants that are safe for the environment and exhibit potential weak activity towards storage pests. An essential aspect of this work was also the correlation of herbicidal activity with the wettability of hydrophobic surfaces. [ABSTRACT FROM AUTHOR]

The increasing limitations regarding the applied amounts of plant protection make hybrid ionic liquids an interesting class of compounds belonging to the III generation ILs. There are known examples of biologically active compounds in the literature, the structure of which is based on a monoalkyl derivative of 1,4-diazabicyclo[2.2.2]octane (DABCO). In the framework of the presented study, an efficient three-step method was developed for the synthesis of novel bicyclic herbicidal ionic liquids in which an alky derivative of DABCO was used as the cation and the 4-chloro-2-methylphenoxyacetic anion originated from a commonly applied herbicidal acid, MCPA. The synthesized new ILs were purified and identified and their surface activity, thermal stability and solubility were characterized. Furthermore, their herbicidal activity under greenhouse conditions towards common weed species present in agricultural crops and antimicrobial properties were also evaluated. The high biological activity of the synthesized ILs was correlated with their surface active properties. The obtained results confirmed the dual functionality of the synthesized herbicidal ionic liquids. [ABSTRACT FROM AUTHOR]

series of ethoxylates of 2,2,4-trimethyl-1,3-pentanediol mono-isobutyrate representing a synthetic C12 hydroxyester hydrophobe was obtained. The solubility parameters, surface tension and critical micelle concentrations for model solutions were investigated. The new surfactants were found to produce extremely low foam levels and a non-standard surface interfacial behavior was determined. It was observed that the ethoxylates of the C12 hydroxyester formed an oriented monolayer at the interface regardless of their average polyaddition degree. Such behavior is different from the surface activities of commonly known linear nonionic surfactants and it indicates self organization of the surfactants at the interface. This feature offers possibility for application of these surfactants in nanotechnology as well as in the conventional cleaning processes. [ABSTRACT FROM AUTHOR]

A new group of quaternary ammonium ionic liquids with azolate (benzotriazolate, 1,2,4-triazolate, 4-nitroimidazolate, 2-methyl-4-nitroimidazolate) anions was prepared and characterized. The synthetic method employed was easy and quick, and required a polar solvent. The obtained ionic liquids were tested as anti-microbial and anti-fungal plant protection agents. Additionally, the surface-active properties and the phytotoxicity of the quaternary ammonium azolates were also studied. These clearly defined ionic liquids were found to be very effective anti-bacterial and anti-fungal agents. [ABSTRACT FROM AUTHOR]

The Diels-Alder reaction between cyclopentadiene and dienophiles in deanol derivatives containing bis(trifluoromethylsulfonyl)imide anion as media have been studied. The effect of the substituents attached to the cation on the endo:exo selectivity as well as the reaction yield have been evaluated in the absence and presence of Lewis acid catalyst - Y(OTf). Catalytic activity of metal triflates and the recycling of chosen catalytic systems have also been investigated [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The cloud point separation of Direct Yellow from micellar solution of various nonionic surtactants, containing a polyoxyethylene chain, was studied. The separation of dyes is an important environmental problem. Moreover, such separation can also be considered as a preliminary step for further studies of biochemical recovery. Some dyes can be considered as affinity ligands, which form complexes with biochemicals. The use of dye enabled the observation of the dynamics of surfactant-rich phase separation by means of a color video. It was found that the separation of phases was incomplete. The aqueous phase contained some amounts of surlactant globules with the dye. The surfactant-rich phase was usually more heterogenic than the aqueous phase. The recovery of Direct Yellow was very effective in the presence of electrolyte (NaCI). The distribution coefficients were high and equal to a few hundreds in the presence of sodium chloride. Under optimum conditions 98-99.9% of the dye could be removed in the one step. [ABSTRACT FROM AUTHOR]

Investigates the demigration of phenols from aqueous streams. Employment of the cloud point extraction method; Application of oxyethylated methyl dodecanoates as surfactants; Determination of the range of distribution coefficients.