Aqueous two-phase system based on natural quaternary ammonium compounds for the extraction of proteins.

Aqueous two-phase systems, based on the use of natural quaternary ammonium compounds, were developed to establish a benign biotechnological route for efficient protein separation. In this study, aqueous two-phase systems of two natural resources betaine and choline with polyethyleneglycol (PEG400/600) or inorganic salts (K2 HPO4 /K3 PO4 ) were formed. It was shown that in the K2 HPO4 -containing aqueous two-phase system, hydrophobic interactions were an important driving force of protein partitioning, while protein size played a vital role in aqueous two-phase systems that contained polyethylene glycol.

Enzymatic selective synthesis of 1,3-DAG based on deep eutectic solvent acting as substrate and solvent.

In this study, enzymatic selective esterification of oleic acid with glycerol based on deep eutectic solvent acting as substrate and solvent was studied. As choline chloride (ChCl) or betaine can effectively change the chemical reaction characteristics of glycerol when they are mixed with a certain molar ratio of glycerol, several factors crucial to the lipase catalytic esterification of glycerol with oleic acid was investigated. Results showed that, betaine had more moderate effects than ChCl on the lipase, and water content had an important influence of the esterification and the enzyme selectivity.

Childhood obesity and food intake.

Background: The prevalence of obesity among children is growing in China at present. Childhood obesity reflects complex interactions of genetic, environmental, social and behavioral factors. Foods, nutritional components, and food intake patterns may be associated with the increasing obesity rate in children.

Tyrosinase inhibitory effects and antioxidative activities of novel cinnamoyl amides with amino acid ester moiety.

Nine cinnamoyl amides with amino acid ester (CAAE) moiety were synthesized by the conjugation of the corresponding cinnamic acids (cinnamic acid, 4-hydroxy cinnamic acid, ferulic acid and caffeic acid) with amino acid esters, and their inhibitory effects on the activities of mushroom tyrosinase were investigated, using l-3,4-dihydroxyl-phenylalanine (l-DOPA) as the substrate. Among these CAAE amides, ethyl N-[3-(4-hydroxy-3-methoxyphenyl)-1-oxo-2-propen-1-yl]-l-phenylalaninate (b(4)) showed the strongest inhibitory activity; the IC(50) was 0.18 μM.