Magnetic-stirring-enhanced mechanical amorphous dispersion extraction for the hydrophobic phytochemical constituents using an aqueous solution from a medicinal plant.

A method involving chitosan-assisted magnetic-stirring-enhanced mechanical amorphous dispersion extraction was developed and utilized to extract hydrophobic anthraquinones from Rhei Radix et Rhizoma prior to ultrahigh performance liquid chromatography analysis. Incorporating natural chitosan as a dispersant facilitated the extraction of hydrophobic anthraquinones using purified water, considerably enhancing the eco-friendliness of the extraction methodology. To optimize extraction efficiency, an extensive evaluation of the crucial parameters influencing rhubarb yield was conducted. Furthermore, a response surface methodology was applied to optimize the extraction conditions. Under these optimized conditions, the method exhibited linearity ranges of 0.1-100 µg/mL, with correlation coefficients between 0.9990 and 0.9998. The method's intraday (n = 6) and interday (n = 6) precision levels were maintained at ≤3.58%, which was considered to be within acceptable limits. The computed detection and quantification limits were 16.54-24.60 and 54.91-82.04 ng/mL, respectively. Consequently, this optimized method was effectively employed to extract five specific compounds (aloe-emodin, emodin, rhein, chrysophanol, and physcion) from Rhei Radix et Rhizoma, achieving recoveries ranging from 86.43% to 102.75%.

On-line concentration and separation of multiple derivatized monosaccharides from edible fruit with cyclodextrin-encapsulated sweeping by micellar electrokinetic chromatography.

An on-line enrichment and separation of multiple derivatized monosaccharides with cyclodextrin-encapsulated sweeping (CDES) by micellar electrokinetic chromatography (MEKC) was presented. Five monosaccharides (L-(-)-Mannose, D-(+)-Glucose, D-(-)-Ribose, D-(+)-Xylose, and L-(+)-Rhamnose) were derivatized with 1-phenyl-3-methyl-5-pyrazolone, subsequently concentrated and separated by MEKC. The optimized conditions were as follows: 50 mM phosphoric acid (PA), 100 mM sodium dodecyl sulfate (SDS), and 30 % (v/v) methanol in background solution; 140 s injection of sample solution containing 50 mM CD and 100 mM PA, followed by 90 s injection of 40 mM SDS solution. Under the optimized conditions, the correlation coefficients ≥ 0.9953, and the limits of detection ranged from 4.2 to 7.4 ng/mL. Relative standard deviation values ranged from 0.24-4.23 %, and sensitivity enrichment factors were in the range of 53-82 compared with typical injection (50 mbar, 3 s). The CDES-MEKC method was successfully applied to Jujube with good recoveries of 84.22-104.33 %. The method provides new ideas for the on-line enrichment and detection of trace monosaccharides and even other target analytes in foods with complex matrices.