<i>N</i>-Acetylated Gemini Surfactants: Synthesis, Surface-Active Properties, Antifungal Activity, and Ecotoxicity Bioassays

Abstract

A series of N-acetylated cationic gemini surfactants (3a-e) having dimeric structures derived from tertiary amines were synthesized. Their antifungal potency and surface properties were determined. It also studied the acute toxicity of the molecule with the best performance and the best water solubility (3e) through Chlorella vulgaris and Daphnia magna bioassays. The results were compared to those obtained for a commercially available reference compound 2-(thiocyanomethylthio) benzothiazole (TCMTB). Parameters such as surface tension (γ CMC ), critical micelle concentration (CMC), surface excess concentration (Γ), and area per molecule (A) were determined. The resulting values indicated that the five gemini surfactants are characterized by good surface-active and self-aggregation properties. All surfactants were tested to evaluate their antifungal activity. Six fungal strains were used to conduct the study. The minimum inhibitory concentration (MIC) value was measured by the fungal growth inhibition. The results of the MICs were compared with two commercially available reference compounds (Fluconazole and TCMTB). The least active molecule was 3e, but 3b and 3d were found to be the most potent compounds with a similar activity for all strains. Candida albicans was the most sensitive one. In contrast, Aspergillus niger was resistant. Ecotoxicity of gemini 3e was assessed: the commercial formulation (TCMTB) was between three and four orders of magnitude more toxic than the gemini one for the biological species tested.

Coupling between the Dynamics of Water and Surfactants in Lyotropic Liquid Crystals

“…The characterization of gemini bilayer properties is additionally essential for the many proposed biological applications of these surfactants. Gemini surfactants have received considerable interest for applications as antimicrobials, − and as liposome constituents for both drug delivery − and DNA transfection; − in these applications, the surfactant/lipid bilayer interaction is of primary importance. Several mechanistic studies of the interaction between geminis and lipid membranes have been reported.…”

In vitro susceptibility test of Cladosporium cladosporioides isolates from Argentinian tomato crops against commercial fungicides

“…Inoculum concentration was verified by spread plate method. All macrodilution tests were incubated for 48-72 h to determine MIC (Machuca & Murguía, 2020;Machuca et al, 2015). All the tests included drug-free and fungifree controls.…”

Fabrication of Encapsulated Gemini Surfactants

“…From an ecological point of view, the functionalization of substituents with groups of natural origin is of great importance, because it can increase their biological profile, improving biodegradability or reducing ecotoxicity [ 8 , 38 ]. Gemini surfactants are referred to as multifunctional, because one compound may be an exceptionally effective surface active agent [ 39 , 40 , 41 ], corrosion and biocorrosion inhibitor [ 42 , 43 , 44 , 45 , 46 , 47 ], but also has remarkably high antibacterial [ 48 , 49 , 50 , 51 ] and antifungal [ 52 , 53 , 54 , 55 , 56 , 57 ] activity and is effective in preventing biofilm eradication [ 52 , 58 ]. It is worth emphasizing that gemini surfactants work effectively at a very low concentration, often several times smaller in comparison to single quaternary ammonium salts [ 59 , 60 , 61 , 62 , 63 ].…”