Endocrine disrupting potency and toxicity of novel sophorolipid quaternary ammonium salts.

A new class of biosurfactants, namely quaternary ammonium sophorolipids (SQAS), suitable for pharmaceutical applications, was tested for the evaluation of their (anti)estrogenic and (anti)androgenic potency with the help of YES/YAS assays. Also their toxicity towards yeasts (Saccharomyces cerevisiae) and bacteria (Escherichia coli) was checked. The results achieved for SQAS, which can be regarded as potential micropollutants, were compared with those obtained for two well-known micropollutants diclofenac and 17α-ethinylestradiol subjected to the same testing procedures.

Challenges and opportunities of solvent-based additive extraction methods for plastic recycling.

Additives are ubiquitously used in plastics to improve their functionality. However, they are not always desirable in their 'second life' and are a major bottleneck for chemical recycling. Although research on extraction techniques for efficient removal of additives is increasing, it resembles much like uncharted territory due to the broad variety of additives, plastics and removal techniques.

Lipid-Based Quaternary Ammonium Sophorolipid Amphiphiles with Antimicrobial and Transfection Activities.

Twelve new quaternary ammonium sophorolipids with long alkyl chains on the nitrogen atom were synthesized starting from oleic and petroselinic acid-based sophorolipids. These novel derivatives were evaluated for their antimicrobial activity against selected Gram-negative and Gram-positive bacteria and their transfection efficacies on three different eukaryotic cell lines in vitro as good activities were demonstrated for previously synthesized derivatives. Self-assembly properties were also evaluated.

Asymmetrical, Symmetrical, Divalent, and Y-Shaped (Bola)amphiphiles: The Relationship between the Molecular Structure and Self-Assembly in Amino Derivatives of Sophorolipid Biosurfactants.

Conventional head-chain but also more exotic divalent, Gemini, or bolaform amphiphiles have in common well-defined hydrophilic and hydrophobic blocks with often a predictable self-assembly behavior. However, new categories of amphiphiles, such as microbial biosurfactants, challenge such conventional understanding because of the poorly defined boundaries between the hydrophilic and hydrophobic portions. Microbial glycolipids, such as sophorolipids, rhamnolipids, or cellobioselipids, interesting biodegradable, nontoxic, alternatives to synthetic surfactants, all represent interesting examples of atypical amphiphiles with partially predictable self-assembly properties.

Evaluation of biological properties and fate in the environment of a new class of biosurfactants.

Selected sophorolipid quaternary ammonium salts (SQAS), being a new class of modified biosurfactants, were studied in this work for the first time with regard to their biodegradability and fate in the environment. It was made to find whether environment-friendly bioproducts like biosurfactants are still safe to the environment after their chemical modification. The susceptibility of these SQAS for biodegradation was estimated together with the evaluation of their influence on activated sludge microorganisms.

Characterization of French Coriander Oil as Source of Petroselinic Acid.

Coriander vegetable oil was extracted from fruits of French origin in a 23% yield. The oil was of good quality, with a low amount of free fatty acids (1.8%) and a concurrently high amount of triacylglycerols (98%).

Petroselinic acid purification and its use for the fermentation of new sophorolipids.

Petroselinic acid, a positional isomer of oleic acid, was isolated from the vegetable oil of Coriandrum sativum fruits. This uncommon fatty acid was subsequently used as substrate for sophorolipid fermentation with a Starmerella bombicola lactone esterase overexpression (oe sble) strain. A petroselinic acid based diacetylated sophorolipid lactone was obtained in high purity without incorporation of de novo synthesized fatty acids such as oleic acid.