Eudesmane sesquiterpenoid glycosides from the leaves of Pittosporum lenticellatum with anti-neuroinflammatory activity.

Chemical investigation of the EtOAc extract of the leaves of Pittosporum lenticellatum led to the isolation of twenty-five previously undescribed eudesmane sesquiterpenoid glycosides, pitlencosides A－Y (1-25); their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR, HR-ESI-MS, ECD spectra, and X-ray crystallographic analysis. Among them, compounds 4, 5, 7, 8, 15 and 16 exhibited significant inhibitory effects on the production of nitric oxide in lipopolysaccharide-induced BV-2 microglial cells by suppressing the expression of inducible nitric oxide synthase and cyclooxygenase-2, with IC50 values ranging from 7.95 to 25.88 µM, which showed stereo-chemical and substituent dependents. Western blot analysis and molecular docking simulation confirmed the anti-inflammatory activity of compounds 4, 5, 7, 8, 15 and 16.

Further sesquiterpenoids from Pittosporum qinlingense and their anti-inflammatory activity.

Four new sesquiterpenoid glycoside esters, Pitqinlingoside N-Q (1-4), together with eleven known metabolites (5-15), were isolated from 95% EtOH extract of the twigs, fruits and leaves of P. qinlingense. The structures of new compounds were elucidated on the basis of extensive spectroscopic analyses, including IR, UV, HRMS, NMR and electronic circular dichroism spectra. Unusal glycoside esters are characterized by the presence of polyacylated ß-D-fucopyranosyl and ß-d-glucopyranosyl units. Pitqinlingoside N (1), O (2), P (3), boscialin (5) and arvoside C (6) showed significant nitric oxide production inhibition in lipopolysaccharide (LPS)-induced BV-2 microglial cells with IC50 values ranging from 1.58 to 28.74 µM. Structure-activity relationships of the isolated compounds are discussed.

Green Tailoring With Water of Choline Chloride Deep Eutectic Solvents for the Extraction of Polyphenols From Palm Samples.

To address the problem of high viscosity of deep eutectic solvents (DESs), the viscosities of a series of choline chloride-based DESs and DESs-H2O were determined, and their extraction efficiencies were obtained for the extraction of polyphenols in palm samples. Tailoring the DESs by the addition of water successfully adjusted their viscosity from thousand to single-digit mPa s and aided the extraction of polyphenols from samples, by changing the hydrogen-bonding interactions of DESs. Among the compounds investigated, choline chloride-oxalic acid-water of DESs-H2O with various molar ratios with 1:0.1-1:50 showed the greatest change in viscosity with 3617-2 mPa s, and effectively extracted most of the target compounds of polyphenols (52.1 µg mL-1 for protocatechuic acid, 7.3 µg mL-1 for catechins, 34.0 µg mL-1 for epicatechin and 6.2 µg mL-1 for caffeic acid) from samples. The results confirm that tailoring with water can successfully adjust the viscosity and extraction efficiency of DESs, for effective extraction of bioactive compounds from samples.