Steroidsaponine mit mehr als einer zuckerkette, III

Tschesche, Rudolf; Tjoa, B.T.; Wulff, Günter; Noronha, Rudolf

doi:10.1016/s0040-4039(00)72304-5

Cited by 20 publications

(5 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is thought that furostanol saponin exists in the form of just 1a in the roots of Helleborus orientalis Lam and that compound 1b may be artifacts of the extraction and isolation procedure. Such interconversion between hydroxyl and methoxyl groups at C-22 furostanol glycosides has already been reported in the literature [1,4].…”

supporting

confidence: 67%

See 1 more Smart Citation

A furostanol saponin and phytoecdysteroid from roots of Helleborus orientalis

Akin

Anıl

2007

Chem Nat Compd

View full text Add to dashboard Cite

A furostanol saponin mixture and a known phytoecdysteroid were isolated from the roots of Helleborus orientalis Lam. Their structures were established as 1) and of 2 gave 20-hydroxy-β-ecdyson (aglycone 2). Their structures were elucidated by spectral analysis.Helleborus extracts exhibit high biological activity with antialgic, myorelaxant, antirheumatic, and blood vessel regulating actions [1]. Previously isolated classes of constituents, furostanol saponin [2][3][4][5], phytoecdysteroids [6-9], and bufadienolides [10], were characterized from Helleborus species.This study describes the isolation and the exact structure determination of two glycosides, a furostanol saponin 1a,b and a phytoecdysteroid 2, from Helleborus orientalis Lam roots.Compounds 1a,b was obtained as a mixture of the C-22 hydroxyl and C-22 methoxyl forms. It gave two spots at TLC due to the existence of 22-hydroxy and 22-methoxy derivatives of the glycoside. Acid hydrolysis of the mixture gave aglycone 1. The 1 HMR spectral data of aglycone 1 contained signals of olefinic protons at 5.62, 4.78, and 4.83 ppm, two methoxyl protons at 3.21 and 3.63 ppm, and methyl groups at 0.96 (21-CH 3 ), 0.79 (18-CH 3 ), and 1.15 ppm (19-CH 3 ). Furthermore, the presence of a semiketal carbon signal at 109.4 ppm suggested the furostanol nature of the aglycone 1. The EI-MS spectrum showed an ion peak at m/z: 491 [M+H] + for C 29 O 6 H 46 . The above 1 H NMR spectral data and a comparison of the 13 C NMR signals (Table 1) and of -85.92 of aglycone 1 with those described in the literature [1,2] showed the structure of the aglycone1 to be (1β,3β,11α,22α)-22,26-dimethoxyfurosta-5,25(27)-dien-1,3,11-triol.The furostanol glycosidic nature of compounds 1a,b was evidenced by the furostan steroidal structure (916 and 833 cm -1 ) in the IR spectra. The 1 H NMR spectral data of the mixture of compounds 1a,b contained a signal for one anomeric proton at 4.24 ppm (d, J = 7.3 Hz, H-1′). The 13 C NMR spectral data (Table 1) contained an anomeric carbon signal at 104.0 ppm. Furthermore, the presence of a semiketal carbon signal at 110.4 and 110.7 ppm suggested the furostanol nature of compounds 1a,b. The peak intensities of these semiketal carbon signals were 0.775 and 0.742, respectively. The ratio of these components (1a and 1b) in the mixture of was 1:1. The negative FAB-MS showed an ion peak at m/z: 571.4 [M-OCH 3 -2H 2 O] -, suggesting the molecular formula as C 34 O 11 H 54 . The structure of 1a was established as 26-[(β-D-glucopyranosyl)oxy]-22α-hydroxyfurosta-5,25(27)-dien-1β,3β,11α-triol and 1b as 26-[(β-D-glucopyranosyl)oxy]-22α-methoxyfurosta-5,25 (27)-dien-1β,3β,11α-triol. In this paper, the NMR data of 1a and 1b are reported for the first time. Compounds 1a,b are presumed to exist as C-22 hydroxyl and C-22 methoxyl derivatives. It is thought that furostanol saponin exists in the form of just 1a in the roots of Helleborus orientalis Lam and that compound 1b may be artifacts of the extraction and isolation procedure. Such interconversion between hydroxyl and methox...

show abstract

supporting

confidence: 67%

“…Previously isolated classes of constituents, furostanol saponin [2][3][4][5], phytoecdysteroids [6-9], and bufadienolides [10], were characterized from Helleborus species.…”

mentioning

confidence: 99%

A furostanol saponin and phytoecdysteroid from roots of Helleborus orientalis

Akin

Anıl

2007

Chem Nat Compd

View full text Add to dashboard Cite

show abstract

“…18 The sugar moieties at C-3 are essential for the antimicrobial effects of 26-deglucoavenacosides, 21 and these saponins can be detoxified via sequential hydrolysis of the sugar units at C-3 by α-rhamnosidase and β-glucosidase secreted by pathogenic fungi. 21 To date there are only six steroidal saponins purified from oat brans, including avenacoside A, 1, 22 avenacoside B, 2, 23 and avenacoside C, 3, 24 and 26-desglucoavenacosides A and B 11,25,26 as well as one sulfated saponin. 19 Saponins are one type of widespread defense compound in the plant kingdom, 27 and they are mainly characterized for their antimicrobial effects and less frequently for insecticidal properties.…”

Section: ■ Introductionmentioning

confidence: 99%

Steroidal Saponins in Oat Bran

Yang

Wang

et al. 2016

J. Agric. Food Chem.

View full text Add to dashboard Cite

Saponins are one type of widespread defense compound in the plant kingdom and have been exploited for the production of lead compounds with diverse pharmacological properties in drug discovery. Oats contain two unique steroidal saponins, avenacoside A, 1, and avenacoside B, 2. However, the chemical composition, the levels of these saponins in commercial oat products, and their health effects are still largely unknown. In this study, we directly purified 5 steroidal saponins (1-5) from a methanol extract of oat bran, characterized their structures by analyzing their MS and NMR spectra, and also tentatively identified 11 steroidal saponins (6-16) on the basis of their tandem mass spectra (MS(n), n = 2-3). Among the five purified saponins, 5 is a new compound and 4 is purified from oats for the first time. Using HPLC-MS techniques, a complete profile of oat steroidal saponins was determined, and the contents of the two primary steroidal saponins, 1 and 2, were quantitated in 15 different commercial oat products. The total levels of these two saponins vary from 49.6 to 443.0 mg/kg, and oat bran or oatmeal has higher levels of these two saponins than cold oat cereal. Furthermore, our results on the inhibitory effects of 1 and 2 against the growth of human colon cancer cells HCT-116 and HT-29 showed that both had weak activity, with 2 being more active than 1.

show abstract

“…Recovery studies were performed by spiking known concentrations of avenanthramides 5−10 to oat flour samples at three different concentrations. A comparison to those amounts found in unspiked oat flour samples resulted in average recovery of 53.7% (9), 56.3% (8), 78.5% (10), 90.3% (5), 95.5% (6), and 98.3% (7).…”

Section: ■ Results and Discussionmentioning

confidence: 89%

“…To identify which non-volatile, key taste molecules impart the bitterness and astringency of oats, we recently applied the so-called taste dilution analysis (TDA) 11 on fractions isolated from oat flour after sequential solvent fractionation and separation by means of solid-phase extraction (SPE) followed by high-performance liquid chromatography (HPLC). 1 This activity-guided fractionation led to the identification of four steroidal and furostanol saponins as well as three avenanthramides 2c (5), 2p (6), and 2f (7) as key bitter and astringent phytochemicals in oats. Sensory evaluation of these saponins and avenanthramides showed potent bitter sensation with taste recognition thresholds between 4 and 170 μmol/L, with saponin 3-(O-α-L-rhamnopyranosyl(1→2)-[β-Dglucopyranosyl(1→3)-β-D-glucopyranosyl(1→4)]-β-D-gluco-pyranosid)-26-O-β-D-glucopyranosyl-(25R)-furost-5-ene-3β,22,26-triol (1) exhibiting by far the lowest bitter threshold.…”

Section: ■ Introductionmentioning

confidence: 99%

Quantitation and Taste Contribution of Sensory Active Molecules in Oat (Avena sativa L.)

Günther-Jordanland

Dawid

Hofmann

2020

J. Agric. Food Chem.

View full text Add to dashboard Cite

A total of 59 taste-active molecules were quantitated and then rated for their individual taste impact on the basis of dose-over-threshold factors in oat flour (Avena sativa L.). A sensitive high-performance liquid chromatography–tandem mass spectrometry method was developed to quantitate bitter-tasting steroidal and furostanol saponins as well as avenanthramides. Four monoglycerides, five free fatty acids and four saponins were confirmed for the first time to be major contributors to the bitter off-taste of oats, among them 1-linoleoyl-rac-glycerol, 1-stearoyl-rac-glycerol, 1-oleoyl-rac-glycerol, 1-palmitoyl-rac-glycerol, linoleic acid, linolenic acid, oleic acid, palmitic acid, and stearic acid as well as avenacosides A and B and the recently identified furostanosides 3-(O-α-l-rhamnopyranosyl(1→2)-[β-d-glucopyranosyl(1→3)-β-d-glucopyranosyl(1→4)]-β-d-glucopyranosid)-26-O-β-d-glucopyranosyl-(25R)-furost-5-ene-3β,22,26-triol and 3-(O-α-l-rhamnopyranosyl(1→2)-[β-d-glucopyranosyl(1→4)]-β-d-glucopyranosid)-26-O-β-d-glucopyranosyl-(25R)-furost-5-ene-3β,22,26-triol. By means of a stable isotope dilution assay, quantitated avenanthramides 2c, 2p, 2f, 1p, 1c, 1f, and 3f were found in concentrations below their thresholds and, therefore, did not contribute to the bitter sensation of the tested oat flour.

show abstract

Steroidsaponine mit mehr als einer zuckerkette, III

Cited by 20 publications

References 6 publications

A furostanol saponin and phytoecdysteroid from roots of Helleborus orientalis

A furostanol saponin and phytoecdysteroid from roots of Helleborus orientalis

Steroidal Saponins in Oat Bran

Quantitation and Taste Contribution of Sensory Active Molecules in Oat (Avena sativa L.)

Contact Info

Product

Resources

About