Countercurrent chromatographic isolation of 11´-γ-tocomonoenol from and detection of novel minor tocochromanols in pumpkin seed oil

A non-refined, organic pumpkin seed oil (PSO) was chosen for the isolation and structure verification of the rare vitamin E compound γ-tocomonoenol (γ-T1). Initial measurements indicated the presence of ~0.4 mg γ-T1 per 100 g pumpkin seed oil. Saponification of ~2 L pumpkin seed oil, followed by repeated countercurrent chromatography (CCC) with the solvent system n-hexane/benzotrifluoride/acetonitrile (10:3.5:6.5, v/v/v) and silica gel column chromatography enabled the isolation of 6.8 mg γ-T1 with a purity of 96.0%. Structural analysis by H NMR spectroscopy and gas chromatography with mass spectrometry (GC/MS) of the γ-T1 isolate confirmed the presence of a double bond in C-11´-position (11´-γ-tocomonoenol). Next to γ-T1, CCC fractionation enabled the detection of 18 different tocochromanols, many of which were reported for the first time in pumpkin seed oil. This unmatched variety covered among others α-/γ-tocopherol, α-/γ-tocomonoenol, two α- and two γ-tocodienol isomers, α-/γ-tocotrienol as well as the rare 11´-β-tocomonoenol (β-T1) and δ-T1. Three uncommon tocochromanols were also detected whose origins and structure remained unclear.

Modulatory properties of cardiac and quercetin glycosides from Dacryodes edulis seeds during L-NAME-induced vascular perturbation

BackgroundNumerous food wastes have been identified to possess potent bioactive compounds used for the treatment of several diseases. Therefore this study evaluated the potentials of cardiac and quercetin glycosides extracted from Dacryodes edulis seeds to reverse vascular and endothelial damage (VAED).MethodsThe glycoside composition of the seeds was extracted using standard methods and characterized by gas chromatography. We then recruited rats with L-NAME-induced VAED based on confirmatory biomarkers cardiac troponin (CnT), cellular adhesion molecule (VCAM-1), lipoprotein associated phospholipase A2 (Lp-PLA2), RAAS, VWF, endothelin, eNOx, and homocysteine. Only rats that showed total alterations of all biomarkers were recruited into the respective experimental groups and treated with either metaprolol succinate (met.su) + losartan or glycoside extracts of D. edulis seeds (NPSG).ResultsChromatographic isolation of glycosides in the seed showed predominance of artemetin (1.59 mg/100 g), amygdalin (3.68 mg/100 g), digitoxin (19.21 mg/100 g), digoxin (27.23 mg/100 g), avicularin (133.59 mg/100 g), and hyperoside (481.76 mg/100 g). We observed decreased water intake and higher heart beats under vascular damage as the experiment progressed up to the fourth week. The met.su + losartan and H.D NPSG proved effective in restoring troponin, but both doses of NPSG normalized the VCAM-1 and RAAS activities excluding aldosterone and Lp-PLA2. Among the endothelial dysfunction biomarkers, H.D NPSG produced equivalent effects to met.su + losartan towards restoring the eNOx and VWF activities, but showed higher potency in normalizing the endothelin and Hcy levels.ConclusionsWe thus propose that the synergistic effect of the isolated glycosides from D. edulis shown in our study proved potent enough at high doses in treatment of vascular and endothelial dysfunction.