[Quality control method for phenolic acid components in abandoned stems and leaves of Artemisia selengensis based on UPLC fingerprint combined with quantitative analysis of multi-components by single marker (QAMS)].

This study established an ultra-performance liquid chromatography(UPLC) fingerprint of abandoned stems and leaves of Artemisia selengensis and quantitative analysis of multi-components by single marker(QAMS) for five phenolic acid components. Waters Acquity UPLC BEH C_(18) chromatography column(2.1 mm×100 mm, 1.7 µm) was used. The gradient elution was carried out with the mobile phase composed of 0.1% phosphoric acid water and acetonitrile at a flow rate of 0.3 mL·min~(-1) and a column temperature at 30 ℃. The detection wavelength was 330 nm, and the injection volume was 2 µL. Similarity evaluation and cluster analysis were conducted on the fingerprint data, and 15 common components in 13 batches of abandoned stems and leaves of A. selengensis were identified. The relative correction factors of ferulic acid, isochlorogenic acid A, isochlorogenic acid B, and isochlorogenic acid C were calculated using chlorogenic acid as the internal reference. The QAMS for determining five components in the abandoned stems and leaves of A. selengensis was established. At the same time, the content of these five components was determined using the external standard method(ESM), and the results showed that there were no significant differences in their content determined by the QAMS and the ESM. The results indicated that the content of phenolic acid components in the abandoned stems and leaves of A. selengensis from different varieties and different origins had obvious differences. In addition, the content of phenolic acid components in the abandoned stems and leaves of lignified A. selengensis was significantly higher than that of non-lignified A. selengensis. In summary, QAMS established in this study can be quickly, accurately, and economically used to determine the content of five phenolic acid components in abandoned stems and leaves of A. selengensis, laying a foundation for the resource development and utilization of abandoned stems and leaves of A. selengensis.

Comprehensive reutilization of Glycyrrhiza uralensis residue by extrusion-biological pretreatment for coproduction of flavonoids, cellulase, and ethanol.

A continuous chemical-free green approach was investigated for the comprehensive reutilization of all components in herbal extraction residues (HERs), taking Glycyrrhiza uralensis residue (GUR) as an example. The GUR structural changes induced by mechanical extrusion which improve the specific surface area and enzyme accessibility of GUR. With 3 % pretreated GUR loading of high-tolerance Penicillium oxalicum G2. The reducing sugar yield of 11.45 g/L was achieved, along with an 81.06 % in situ enzymatic hydrolysis. Finally, 8.23 g/L bioethanol (0.40 g/g total sugar) was produced from GUR hydrolysates after 24 h fermentation of Pichia stipitis G32. The amount of functional medicinal ingredients extracted from GUR after hydrolysis (39.63 mg/g) was 37.69 % greater than that of un-pretreated GUR. In total, 1.49 g flavonoids, 294.36 U cellulase, and 14.13 g ethanol could be produced from 100 g GUR using this process, illustrating that this green and efficient process has the potential for industrial production.

Biosynthesis of a water solubility-enhanced succinyl glucoside derivative of luteolin and its neuroprotective effect.

The natural flavonoids luteolin and luteoloside have anti-bacterial, anti-inflammatory, anti-oxidant, anti-tumour, hypolipidemic, cholesterol lowering and neuroprotective effects, but their poor water solubility limits their application in industrial production and the pharmaceutical industry. In this study, luteolin-7-O-ß-(6″-O-succinyl)-d-glucoside, a new compound that was prepared by succinyl glycosylation of luteolin by the organic solvent tolerant bacterium Bacillus amyloliquefaciens FJ18 in an 8.0% DMSO (v/v) system, was obtained and identified. Its greater water solubility (2293 times that of luteolin and 12 232 times that of luteoloside) provides the solution to the application problems of luteolin and luteoloside. The conversion rate of luteolin (1.0 g l-1 ) was almost 100% at 24 h, while the yield of luteolin-7-O-ß-(6″-O-succinyl)-d-glucoside reached 76.2%. In experiments involving the oxygen glucose deprivation/reoxygenation injury model of mouse hippocampal neuron cells, the cell viability was significantly improved with luteolin-7-O-ß-(6″-O-succinyl)-d-glucoside dosing, and the expressions of the anti-oxidant enzyme HO-1 in the nucleus increased, providing a neuroprotective effect for ischemic cerebral cells. The availability of biosynthetic luteolin-7-O-ß-(6″-O-succinyl)-d-glucoside, which is expected to replace luteolin and luteoloside, would effectively expand the clinical application value of luteolin derivatives.