Lignin conversion to β-ketoadipic acid by via metabolic engineering and bioprocess development.

Bioconversion of a heterogeneous mixture of lignin-related aromatic compounds (LRCs) to a single product via microbial biocatalysts is a promising approach to valorize lignin. Here, KT2440 was engineered to convert mixed p-coumaroyl- and coniferyl-type LRCs to β-ketoadipic acid, a precursor for performance-advantaged polymers. Expression of enzymes mediating aromatic -demethylation, hydroxylation, and ring-opening steps was tuned, and a global regulator was deleted.

Superanionic Solvent-Free Liquid Enzymes Exhibit Enhanced Structures and Activities.

The surface of a carboxylate-enriched octuple mutant of Bacillus subtilis lipase A (8M) is chemically anionized to produce core (8M)-shell (cationic polymer surfactants) bionanoconjugates in protein liquid form, which are termed anion-type biofluids. The resultant lipase biofluids exhibit a 2.5-fold increase in hydrolytic activity when compared with analogous lipase biofluids based on anionic polymer surfactants.

Edible oleogels as solid fat alternatives: Composition and oleogelation mechanism implications.

The growing awareness of the adverse health effects of trans-fats and saturated fats are driving researchers to seek healthy alternatives. A promising strategy to structure liquid oil, called oleogelation, has been a subject of great interest. In the development of oleogels, highly unsaturated oils can be structured through different gelation mechanisms by varying structuring agents (e.

Stability of cellulase in ionic liquids: correlations between enzyme activity and COSMO-RS descriptors.

Ionic liquids (ILs) are effective in pretreating cellulose for enhanced enzymatic saccharification, however ILs can inactivate cellulases. To guide the selection of ILs, the activity of cellulase was correlated with COSMO-RS calculations and descriptors of ILs including hydrogen bond (H-bond) basicity/acidity, polarity and ion size. Trends were deduced using an anion-series and a cation-series of ionic liquids in aqueous solutions.

Synergistic effects of binary ionic liquid-solvent systems on enzymatic esterification of esculin.

This work established a binary ionic liquid-solvent system for effective enzymatic esterification of naturally occurring phenolic glycosides (flavonoids); which could result in a dramatic enhancement of Novozym 435-catalyzed esterification of esculin, demonstrating a great synergetic effect. In essence, [OMIM][BF]-toluene and [TOMA][TfN]-hexane binary systems both served >90 mol% of conversions of esculin after 96 h of reaction at 60 °C. Typically, binary [TOMA][TfN]-hexane system enabled Novozym 435 with extremely high catalytic efficiency (k/K = 17.

Mapping the location of DATEM in multi-phase systems: Synthesis and characterization of spin-label probe analogues.

Electron paramagnetic resonance (EPR) spectroscopy has emerged as a fast, reliable, non-invasive and sensitive method to determine the distribution, localization and reactivity of labelled ingredients in micro-heterogeneous systems. However, the commercially available probe molecules are very limited. In the present work, five new nitroxide [(4-hydroxy-2, 2, 6, 6-tetramethylpiperidin-1-oxyl (TEMPOL)] derivatives (1b-5b) of diacetyl tartaric acid esters of monoglycerides (DATEM) (1a-5a), a widely used food emulsifier, were synthesized under Steglich conditions and characterized by MS (mass-spectrometry), FT-IR (Fourier-transform infrared spectroscopy), EPR, NMR (nuclear magnetic resonance spectroscopy), fluorescence spectroscopy, and DSC (differential scanning calorimetry) analysis.

Aspartic-Acid-Based Ampholytic Amphiphiles: Synthesis, Characterization, and pH-Dependent Properties at Air/Water and Oil/Water Interfaces.

A facile and two-step strategy was employed to synthesize a series of novel aspartic-acid-based ampholytic amphiphiles from sustainable and commercially viable substances as starting materials. The molecular structures of the synthetic compounds were well-identified by mass spectrometry and H/C nuclear magnetic resonance analysis, and the physicochemical, pH-dependent foaming, and emulsifying properties were evaluated by the use of multiple techniques, such as Fourier transform infrared spectroscopy, differential scanning calorimetry, Langmuir-Blodgett study, and fluorescence microscopy imaging. As a result of the co-existence of amino and carboxyl groups in the synthetic compounds, the compounds presented varying charges (cationic, ampholytic, and anionic) depending upon the pH of the medium compared to the dissociation constants (p K).

Enhanced fish oil-in-water emulsions enabled by rapeseed lecithins obtained under different processing conditions.

It is hypothesized that rapeseed lecithins may have different emulsifying and antioxidant properties in delivering fish oil compared to soy lecithin based on previous studies. The results showed that in vitro antioxidant activities of rapeseed lecithins were stronger than those of soy lecithin. Emulsions stabilized by rapeseed based lecithins and DATEM were stable over 3 months at 4 °C, whereas the creaming of emulsions containing soy lecithin started immediately after its preparation.