Publications by authors named "Evamaria Hofmann"

A significant synergistic effect is observed when solubilizing curcumin or tetrahydrocurcumin in binary mixtures of ethanol and triacetin. The present work deals with a detailed investigation of the solvent system by means of COSMO-RS-based calculations, dynamic light scattering, small-and-wide-angle X-ray scattering, and dielectric relaxation spectroscopy. Theoretical calculations lead to the conclusion that the enhanced solubility is not primarily the result of an interaction optimum between individual surface charge densities.

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The demand for natural vanilla extract, and vanillin in particular, by far exceeds the current production, as both the cultivation of vanilla beans and the extraction of vanillin are laborious. For this purpose, most vanillin used today is produced synthetically, contrary to the general trend toward bio-based products. The present study deals with the synthesis of nature-based vanillin, starting with the more accessible rhizomes of the plant Curcuma longa.

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The amino alcohol meglumine solubilizes organic compounds in water and enforces the formation of electron donor acceptor (EDA) complexes of haloarenes with indoles, anilines, anisoles or thiols, which are not observed in organic solvents. UV-A photoinduced electron transfer within the EDA complexes induces the mesolytic cleavage of the halide ion and radical recombination of the arenes leading, after rearomatization and proton loss to C-C or C-S coupling products. Depending on the substitution pattern selective and unique cross-couplings are observed.

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Curcumin is a powerful coloring agent widely used in the food industry. Its extraction from the plant Curcuma longa is commonly done with aqueous solvent solutions. In contrast to the conventional extraction methods, the present study aimed to compare two different green and bio-based surfactant-free microemulsion (SFME) extraction systems, which are approved for food and yield a higher extracting power of curcuminoids.

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