Fast Isolation of Flavonoids from the Endemic Species Nolana ramosissima I.M. Johnst and Its Endothelium-Independent Relaxation Effect in Rat Aorta

Abstract

The infusion of the desertic plant Nolana ramosissima I.M. Johnst showed vascular smooth muscle relaxation in rat aorta and the presence of several phenolic compounds, which were detected by high resolution UHPLC-Orbitrap-HESI-MS. In addition, five flavonoids were rapidly isolated from a methanolic extract using high-performance counter-current chromatography (HPCCC). The N. ramosissima extract showed endothelium-independent relaxation effect in rat aorta. Sixty-one compounds were detected in the infusion, mainly glycosylated flavonoids, flavanones and several oxylipins, suggesting that a synergistic effect between the compounds in the extracts could be responsible for the relaxation activity. Vascular activity experiments were done in isolated organ bath. In rat aorta, a nitric oxide inhibitor did not prevent the relaxation effects of the extract; however, a selective guanylyl cyclase inhibitor partially blunted this effect. The compound 5,3 -dihydroxy-4 7-dimethoxyflavone presented higher relaxation effect than 100 µg/mL of N. ramosissima extract. The extract and the isolated metabolites from N. ramosissima can show relaxation effects on rat aorta by a mechanism that is independent of the endothelium.

Exploring Antiparasitic Molecule Sources from Timber by-Product Industries—Leishmanicidal and Trypanocidal Compounds from Clathrotropis brunnea Amshoff

“…The compound structures were assigned based on HRMS and 1D and 2D NMR ( Supplementary Figure S1 , Figure 1 ). The compound 5-hydroxy-7-methoxy flavanone (pinostrobin) has previously been reported in the literature ( Cifuentes et al, 2020 ) and 3,5-dimethoxystilbene, was isolated from several plants, including Alpinia katsumadai ( Ngo and Brown, 1998 ).…”

Chemical Fingerprinting, Isolation and Characterization of Polyphenol Compounds from Heliotropium taltalense (Phil.) I.M. Johnst and Its Endothelium-Dependent Vascular Relaxation Effect in Rat Aorta

“…When chemical structures of the compound 1 (pinostrobin; 5-hydroxy-7-methoxy-flavanone) and 3 (sakuranetin; 4′,5 -dihydroxy-7-methoxyflavanone) were compared, we discovered that the increase of the vascular relaxation of compound 3 might be due to the inclusion of the free OH group at position 4′. In a previous study, we found that free OH groups in position 5 and 3′ were also important for the increase of the vascular relaxation in isolated metabolites from N. ramosissima [ 36 ]. On the other hand, the vascular relaxation effect between compounds 3 and 4 was not significantly different ( Figure 8 ).…”

Phenolic Profile, Antioxidant and Enzyme Inhibition Properties of the Chilean Endemic Plant Ovidia pillopillo (Gay) Meissner (Thymelaeaceae)

“…As far as we know, there are also no scientific reports concerning to the antioxidant and enzyme inhibition potential of extracts from the plant. Our group recently investigated the enzyme inhibitory properties plus the antioxidant and chemical fingerprinting of several Chilean native plants and fruits [8][9][10][11][12]. Following our studies on South American plants, we now report the phenolic fingerprinting from ethanolic extracts of Lloime leaves by UHPLC-MS analysis, antioxidant activity and enzyme inhibitory potential (against cholinesterase and tyrosinase) for the first time.…”