A new alkaloid and two organic acids from Portulaca oleracea L. and their bioactivities.

A new alkaloid, identified as 1-benzyl-2-nitroso-1,2,3,4-tetrahydroisoquinoline-6,7-diol, named oleraisoquinoline (1), and five organic acids and two esters, identified as 5-(hydroxymethyl)furan-2-carboxylic acid (2), 1H-pyrrole-2,5-dicarboxylic acid (3), (7E,10E)-octadeca-7,10-dienoic acid (4), (10E,13E)-octadeca-10,13-dienoic acid (5), (7E,10E)-hexadeca-7,10-dienoic acid (6), methyl tridecanoate (7) and methyl (9E,12E)-octadeca-9,12-dienoate (8), were isolated from Portulaca oleracea L., among which compounds 2 and 4‒7 were isolated for the first time. Moreover, the anti-inflammatory activities of compounds 1‒3 were studied, especially, compound 1 presented good inhibitory effects on the production of inflammatory factors IL-1ß and TNF-α.

A new alkaloid from Portulaca oleracea L. with its anti-inflammatory activity.

A new isoindole alkaloid, 6-hydroxy-2-(4'''-hydroxy-3'''-methoxyphenethyl)-4-(4'-hydroxy-3'-methoxyphenyl)-7-methoxy-1H-benzo[f]isoindole-1,3(2H)-dione, named oleraisoindole B was isolated from Portulaca oleracea L., its structure was elucidated using NMR and UHPLC-ESI-Q-TOF/MS spectroscopic methods, and presented anti-inflammatory activity at 5 µM.

A novel skeleton alkaloid from Portulaca oleracea L. and its bioactivities.

A novel skeleton alkaloid was obtained from Portulaca oleracea L., which was identified as 10,11-dihydroxybenzo[5',6'] pentaleno[1',2':3,4]pyrrolo[2,1-b]oxazol-7(11bH)-one, named oleracone M, and its structure was determined using UHPLC-ESI-QTOF/MS, 1D NMR and 2D NMR spectroscopy, and circular dichroism. Then the bioactivities of the compound were investigated including the anti-inflammatory, anti-acetylcholinesterase and antioxidant activities. The results showed that the novel skeleton alkaloid exhibited the potent effect on inhibiting the secretion of IL-1ß at 10 µM, anticholinesterase activity with IC50 value of 49.58 µM, and antioxidant activity with IC50 value of 66.43 µM.

Two new natural products from Portulaca oleracea L. and their bioactivities.

Two new natural products, belonging to alkaloids, identified as ((2R,3S,4R,5R)-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl acetate (1) and (5-hydroxypyridin-2-yl)methyl acetate (2), were isolated from Portulaca oleracea L. The structures were identified by spectroscopic methods, including 1D, 2D NMR, and UHPLC-ESI-QTOF/MS methods. Meanwhile, the anti-inflammatory and anticholinesterase bioactivities were found in these two compounds.

A novel alkaloid from Portulaca oleracea L. and its anti-inflammatory activity.

A novel alkaloid identified as methyl 8,9-dihydroxy-11-oxo-6,11-dihydro-5H-benzo[d]pyrrolo[1,2-a]azepine-3-carboxylate, named portulacatone A (1) with six known compounds Oleracein E (2), 6,7-dihdroxy-3,4-dihydro-2H-isoquinolin-1-one (3), N-trans-p-coumaroytyramine (4), 9H-carbazole (5), isoaspergin (6) and flavoglaucin (7) were obtained from Portulaca oleracea L., while compounds (5-7) were isolated from the plant for the first time. The new structure was identified by using UHPLC-ESI-Q-TOF/MS, 1D, 2D NMR and the others were proved by 1H-NMR and 13C NMR that comparing with previous reports. It was suggested that the portulacatone A (1) can significantly inhibit the inflammatory factor, interleukin-1ß (IL-1ß) in the RAW 264.7 cells induced by LPS.

Two new homoisoflavones from Portulaca oleracea L. and their activities.

Two new compounds, identified as 3-(2-hydroxybenzyl)-6,8-dimethoxy-4H-chromen-4-one (1), named oleracone J and 3-(2-hydroxybenzyl)-6,8-dimethoxychroman-4-one (2), named oleracone K, were isolated from Portulaca oleracea L., and the structures of them were determined by spectroscopy, including one-dimensional and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionisation time-of-flight mass spectrometry. The two compounds have scavenging activities in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay, with IC50 values of 18.34, 23.92 µM, and anticholinesterase activities with IC50 values of 59.08, 67.89 µM, respectively.

Seven compounds from Portulaca oleracea L. and their anticholinesterase activities.

A novel lignan, identified as 4-(3,4-dihydroxyphenyl)-6,7-dimethoxy-3a,4-dihydronaphtho[2,3-c]furan-1(3H)-one, named oleralignan A (1), together with six known compounds, loliolide (2), isololiolide (3), dehydrololiolide (4), daphnetin (5), esculetin (6), and trans-coumaric acid methyl ester (7) was obtained from Portulaca oleracea L., while compounds 3, 4, 6, and 7 were isolated from the plant for the first time. Their structures were elucidated using spectroscopic methods, including one- and two-dimensional NMR and high-resolution electrospray ionization time-of-flight mass spectrometry. In addition, the results of activity assay demonstrated that compounds 1-7 have anticholinesterase activities.

Two new organic acids from Portulaca oleracea L. and their anti-inflammatory and anticholinesterase activities.

Two new organic acids, identified as (7E,9E,12E)-pentadecyl-7,9,12-trienoic acid, named Oleraceacid A (1), and 6,7-dihydroxy-4-(4-hydroxy-3,5-dimethoxyphenyl)-2-naphthoic acid, named Oleraceacid B (2), were isolated from Portulaca oleracea L.. The structures were verified by spectroscopic methods, including UHPLC-ESI-QTOF/MS, 1 D and 2 D NMR. Both Oleraceacid A (1) and Oleraceacid B (2) at 20 µM inhibited the inflammatory factor, IL-1ß in the RAW 264.7 cells induced by LPS, moreover, Oleraceacid A (1) can inhibit cholinesterase activity.

A new alkaloid from Portulaca oleracea L. and its anti-inflammatory activity.

A new alkaloid, identified as (E)-2-(4-hydroxyphenyl)-3-(pyridazin-3-yl)-acrylaldehyde, named oleradazine, was isolated from Portulaca oleracea L., and the structure was elucidated using spectroscopic methods, including 1D and 2D NMR spectroscopic and UHPLC-ESI-QTOF/MS methods. In addition, the compound was used to investigate its anti-inflammatory activity in lipopolysaccharide-stimulated macrophages. It was suggested that the oleradazine can significantly inhibit the inflammatory factors, interleukin 1ß and nitric oxide in lipopolysaccharide-stimulated RAW 264.7 cells by enzyme-linked immunosorbent assays.

Three novel alkaloids from Portulaca oleracea L. and their anti-inflammatory bioactivities.

Three novel alkaloids, identified as (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxyphenyl)acrylamide (1), named oleracrylimide A, (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxy-3-methoxyphenyl)acrylamide (2), named oleracrylimide B, and (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxy-3-methoxyphenyl)acrylamide (3), named oleracrylimide C were isolated from Portulaca oleracea L. and the structures of the three novel compounds were determined by 1D and 2D NMR, circular dichroism, and UHPLC-ESI-QTOF/MS spectroscopic methods. Moreover, the bioactivities of anti-inflammation of the three compounds were investigated via testing RAW 264.7 macrophage cell stimulated by Lipopolysaccharide.

Three new alkaloids from Portulaca oleracea L. and their bioactivities.

Three novel alkaloids, named oleracone L (1), portulacatone B (2), and portulacatal (3), were isolated from P. oleracea L.. The structures were determined using UV, IR, 1D and 2D NMR spectroscopy and UHPLC-ESI-QTOF/MS. The three compounds in a dose-dependent manner significantly reduced the secretion of IL-1ß in the lipopolysaccharide-stimulated macrophages RAW 264.7 cell culture supernatant, moreover, exhibited the anticholinesterase activities.

A new skeleton flavonoid and a new lignan from Portulaca oleracea L. and their activities.

A new skeleton flavonoid, identified as (5aR)-10-hydroxy-8-methoxy-5aH,11H-chromeno[2,3-b]chromen-11-one (1), named oleracone G, and a new lignan, confirmed as 8-(4-hydroxy-3-methoxyphenyl)-3-methoxynaphthalen-2-ol (2), named oleralignan B, were isolated from Portulaca oleracea L., and the structures of them were determined using spectroscopic methods including UV, IR, 1D NMR, 2D NMR, and UHPLC-ESI-QTOF/MS. In addition, compounds 1-2 were applied to investigate the anti-inflammatory activities on lipopolysaccharide-stimulated macrophages and scavenging effects in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical. The results showed that the two compounds at 10 µM and 20 µM could dose-dependently decrease the secretion of interleukin 1ß in RAW 264.7 cells by enzyme-linked immunosorbent assay, moreover, presented remarkable antioxidant activities with IC50 values of 27.57, 20.12 µM, respectively.

Bioactivities of 7'­ethoxy­trans­feruloyltyramine from Portulaca oleracea L. and its metabolism in rats using ultra­high­performance liquid chromatography electrospray coupled with quadrupole time­of­flight mass spectrometry.

This research aims to study the antioxidation and anticholinesterase activities of 7'-ethoxy-trans-feruloyltyramine (ETFT), which was an alkaloid isolated from Portulaca oleracea for the first time. Furthermore, its main metabolites and metabolic pathways in rats were also explored. The antioxidation and anticholinesterase effects of ETFT were, respectively, examined using 1,1-diphenyl-2-picrylhydrazyl assay and modified Ellman's method. The results showed that ETFT exhibited both the good antioxidant and anticholinesterase effects. Its main metabolites in rats were implemented, and nine metabolites were finally found in the rat's plasma and urine, including the oxidation, reduction, hydrolysis, glucuronidation, sulfation, and glutathionylation process.

Four lignans from Portulaca oleracea L. and its antioxidant activities.

A new lignan, named oleralignan (1) and three known componds (+)-syringaresinol (2), (+)-lirioresinol A (3) and monomethyl 3,3',4,4'-tetrahydroxy-δ-truxinate (4) were isolated from the P. oleracea for the first time. The compound (1) were identified by 1D, 2D NMR spectroscopic methods and high resolution electrospray ionization time-of-flight mass spectrometry. In addition, it was found that the four lignans presented the scavenging activities in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay more than that of hydroxyl anisole (BHA). [Formula: see text].

Two new alkaloids from Portulaca oleracea L. and their bioactivities.

Two new indole alkaloids, identified as (E)-1-(5,6-dihydroxy-1H-indol-1-yl)-3-(4-hydroxyphenyl)prop-2-en-1-one, named oleraindole A (1), and (E)-1-(5,6-dihydroxy-1H-indol-1-yl)-3-(4-hydroxy-3-methoxyphenyl)prop-2-en-1-one, named oleraindole B (2), together with five known indole alkaloids, (-)-neoechinulin A (3), neoechinulin D (4), isoechinulin A (5), MT-6 (6) and echinulin (7) were isolated from the aqueous extract of Portulaca oleracea L. for the first time, using various chromatographic techniques. The structures of seven alkaloids were elucidated by the 1D and 2D NMR and HR-ESI-TOF-MS spectroscopic methods. Oleraindole A (1) and oleraindole B (2) exhibited a relatively high anticholinesterase activity with IC50 values of 55.12 ±â€¯0.20 µΜ and 46.76 ±â€¯0.08 µM, and antioxidant activities with the IC50 values of 16.20 ±â€¯0.11 µM and 13.88 ±â€¯0.06 µM among seven alkaloids.

A new alkaloid from Portulaca oleracea L. and its antiacetylcholinesterase activity.

A new alkaloid, (10E, 12E)-9-ureidooctadeca-10, 12-dienoic acid, named oleraurea (1) and 10 known compounds, p-hydroxybenzaldehyde (2), p-hydroxybenzoic acid (3), p-hydroxyacetophenone (4), benzamide (5), (E)-p-coumaramide (6), (E)-ferulamide (7), soyalkaloid A (8), ß-carboline-3-carboxylic acid (9), 2, 3, 4, 9-tetrahydro-1H-pyrido [3, 4-b] indole-3-carboxylic acid (10), (1S, 3S)-1-methyl-1, 2, 3, 4-tetrahydro-ß-carboline-3-carboxylic acid (11) were obtained from Portulaca oleracea L., in which, compounds 4, 5, 8-11 were isolated from the plant for the first time. The structure of the compound 1 was identified using spectroscopic methods including 1D and 2D NMR, HR-ESI-TOF-MS. The compounds 1, 5-11 presented anticholinesterase activities, but the P. oleracea extract (POE) presented very low anticholinesterase activity.

A new homoisoflavone from Portulaca oleracea L. and its antioxidant activity.

A new compound was identified as 3-(2-hydroxybenzyl)-5,7-dimethoxy-4H-chromen-4-one (or 2'-dihydroxy-5,7-dimethoxy-homoisoflavone), oleracone F (1), together with p-hydroxy ethyl cinnamate (2) and 4-hydroxy-3-methoxy ethyl cinnamate (3) isolated from the Portulaca oleracea L. for the first time and six known compounds, salicylic acid (4), ß-carboline-3-carboxylic acid (5), aurantiamide (6), portulacanone A (7), B (8) and C (9). Their structures were determined using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance and high-resolution electrospray ionization time-of-flight mass spectrometry. Notably, oleracone F (1) presented scavenging activity in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay, with IC50 value of 17.78 µM.

A pharmacokinetic study on oleracone C after oral and intravenous administration.

Oleracone C, a new homoisoflavanone recently isolated from the plant Portulaca oleracea L., has obvious pharmacological activities. Subsequently, its pharmacokinetic profiles in rats' plasma after oral and intravenous administrations were studied by a simple and rapid ultra high-performance liquid chromatography electrospray ionization quadrupole-time of flight mass spectrometry (UHPLC-ESI-Q-TOF/MS) with apigenin as an internal standard (IS). The analysis was performed on an Agilent Zorbax Eclipse Plus C18 Column (2.1 × 50 mm, 1.8 µm) by elution with acetonitrile and water (containing 0.1% formic acid) at a flow rate of 0.3 mL/min. Electrospray ionization in negative ion mode was used to quantify oleracone C and apigenin, with monitored ion m/z values of 299.0915 [M - H]- and 269.0455 [M - H]-. The linear range was established over the concentration range 10-2000 ng/mL (r = 0.9971). The limit of detection (LOD) and limit of quantification (LOQ) were 3 and 10 ng/mL for oleracone C, respectively. The RSD and RE of intra- and inter- day accuracy and precision were all less than 15%. The pharmacokinetic results indicated that oleracone C was rapidly distributed with the time to peak concentrations of 0.03 h and 0.33 h, respectively after intravenous and oral administrations and presented a low absolute bioavailability of 8.32%. This is the first study to successfully examine the pharmacokinetics of homoisoflavanone in rats' plasma after oral and intravenous administrations, using rapid, sensitive and specific UHPLC-ESI-Q-TOF/MS method.

New flavonoids from Portulaca oleracea L. and their activities.

Three new compounds, identified as (3S)-5-hydroxy-3-(2-hydroxybenzyl)-7-methoxychroman-4-one, oleracone C (1), 5-hydroxy-3-(2-hydroxybenzyl)-7-methoxy-4H-chromen-4-one, oleracone D (2), and 1-(2-hydroxy-4,6-dimethoxyphenyl)-3-(2-hydroxyphenyl)propan-1-one, oleracone E (4), together with one new natural product, 5,7-dimethoxy-4-O-2'-cycloflavan (3) already known from synthesis, and two known compounds, (2S)-5,2'-dihydroxy-7-methoxyflavanone (5) and 2',4'-dihydroxy-4,6'-dimethoxychalcone (6) were isolated from the Portulaca oleracea L. for the first time. Their structures were elucidated using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionization time-of-flight mass spectrometry and circular dichroism spectrometry. Oleracone C (1), D (2) and E (4) presented scavenging activities in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay, with IC50 values of 23.27, 11.73, 13.17 µM, respectively and anticholinesterase activities with IC50 values ranging between 59.55 and 78.85 µM.

An isoindole alkaloid from Portulaca oleracea L.

A novel isoindole alkaloid named oleraisoindole (1), together with six known compounds, 7'-ethoxy-trans-feruloyltyramine (2), N-trans-feruloyltyramine (3), N-trans-feruloyl-3-methoxytyramine (4), N-trans-p-coumaroyltyramine (5) aurantiamide (6) and ferulic acid methyl ester (7) were isolated from Portulaca oleracea L. Compounds 2 and 7 were isolated for the first time from this plant. Compound 1 was identified using spectroscopic methods including HR-ESI-TOF-MS, 1D-NMR, 2D-NMR. It was tested in a nitric oxide (NO) inhibition assay and was shown to inhibit NO production in RAW 264.7 cells induced by LPS.