lignans and lyoniresinol

Ten lignans were isolated from the ethanol extract of stems and branches of Rhododendron ovatum through column chromatography over silica gel, ODS, Sephadex LH-20, and MCI-gel resin and semi-preparative RP-HPLC. The structures of all compounds were elucidated by extensive spectroscopic data analysis(UV, IR, HR-ESI-MS, ECD and NMR) as(-)-4-epi-lyoniresinol-9'-O-α-L-rhamnopyranoside(1),(+)-lyoniresinol-3α-O-α-L-rhamnopyranoside(2),(+)-5'-methoxyisolariciresinol-9'-O-α-L-rhamnopyranoside(3),(-)-lyoniresinol-3α-O-β-D-glucopyranoside(4),(+)-lyoniresinol-3α-O-β-D-glucopyranoside(5),(-)-4-epi-lyoniresinol-9'-O-β-D-glucopyransoide(6), racemiside(7), neociwujiaphenol(8),(+)-syringaresinol(9), and homohesperitin(10). Among them, compound 1 was a new aryltetralin-type lignan. All the isolated lignans were tested for antioxidant activities in Fe~(2+)-cysteine induced rat liver microsomal lipid peroxidation in vitro, and compounds 8 and 9 showed antioxidant activities on the formation of malondiadehyde(MDA) in rat liver microsomes at 1×10~(-5) mol·L~(-1), with significant inhibitory rates of 75.20% and 91.12%, respectively.

Topics: Animals; Antioxidants; Glucosides; Lignans; Plant Stems; Rats; Rhododendron

During barrel aging, spirits undergo organoleptic changes caused by the release of aroma and taste compounds. Recently, studies have revealed the bitter properties of oak wood lignans, such as (±)-lyoniresinol, and their contribution to wine taste. To evaluate the impact of lignans in spirits, a targeted screening of 11 compounds was set up and served to validate their presence in this matrix, implying their release by oak wood during aging. After development and validation of a quantification method, the most abundant and the bitterest lignan, (±)-lyoniresinol, was assayed by liquid chromatography⁻high resolution mass spectrometry (LC-HRMS) in spirits. Its gustatory detection threshold was established at 2.6 mg/L in spirits. A large number of samples quantified were above this detection threshold, which suggests its effect of increased bitterness in spirit taste. Significant variations were observed in commercial spirits, with concentrations ranging from 0.2 to 11.8 mg/L, which could be related to differences in barrel aging processes. In "eaux-de-vie" of cognac, concentrations of (±)-lyoniresinol were observed in the range from 1.6 mg/L to 12 mg/L. Lower concentrations were measured for older vintages.

Topics: Alcoholic Beverages; Anisoles; Chromatography, Liquid; Lignans; Mass Spectrometry; Molecular Structure; Naphthalenes; Odorants; Quercus; Taste; Wood

Saraca asoca Linn. (Caesalpiniaceae) is an important traditional remedy for gynaecological disorders and it contains lyoniside, an aryl tetralin lignan glycoside. The aglycone of lyoniside, lyoniresinol possesses structural similarity to enterolignan precursors which are established phytoestrogens.. This work illustrates biotransformation of lyoniside to lyoniresinol using Woodfordia fruticosa Kurz. (Lythraceae) flowers and simultaneous quantification of lyoniside and lyoniresinol using a validated HPTLC method.. The aqueous extract prepared from S. asoca bark was fermented using W. fruticosa flowers. The substrate and fermented product both were simultaneously analyzed using solvent system:toluene:ethyl acetate:formic acid (4:3:0.4) at 254 nm. The method was validated for specificity, accuracy, precision, linearity, sensitivity and robustness as per ICH guidelines.. The substrate showed the presence of lyoniside, however, it decreased as the fermentation proceeded. On 3rd day, lyoniresinol starts appearing in the medium. In 8 days duration most of the lyoniside converted to lyoniresinol. The developed method was specific for lyoniside and lyoniresinol. Lyoniside and lyoniresinol showed linearity in the range of 250-3000 and 500-2500 ng. The method was accurate as resulted in 99.84% and 99.83% recovery, respectively, for lyoniside and lyoniresinol.. Aryl tetralin lignan glycoside, lyoniside was successfully transformed into lyoniresinol using W. fruticosa flowers and their contents were simultaneously analyzed using developed validated HPTLC method.

Topics: Anisoles; Biotransformation; Calibration; Chromatography, High Pressure Liquid; Densitometry; Fermentation; Flowers; Glycosides; Lignans; Linear Models; Naphthalenes; Phytotherapy; Plant Bark; Plants, Medicinal; Reference Standards; Reproducibility of Results; Sitosterols; Woodfordia

Quercoresinosides A and B (1 and 2), two new lignans, were isolated from a toasted Quercus petraea heartwood extract along with a known compound, 3-methoxy-4-hydroxyphenol 1-O-β-d-(6'-O-galloyl)glucopyranoside (3). The purification protocol was based on a taste-guided approach that sought to reveal new bitter compounds released from oak wood into wines and spirits. HRMS and NMR data were used to establish that compounds 1 and 2 are lignan derivatives bearing a glucosyl unit and a galloyl unit at the same positions. Hydrolysis of these compounds showed that they could be distinguished by the absolute configuration of their respective lyoniresinol genin as determined by chiral LC-HRMS in comparison with (+)- and (-)-lyoniresinol standards. Sensory analyses were performed in a non-oaked wine on the pure compounds 1-3. The three molecules exhibited a bitter taste at 2 mg/L that was particularly intense for compounds 2 and 3. Finally, LC-HRMS demonstrated the occurrence of compounds 1-3 in oaked wine and brandy, which supports the hypothesis of their contributions to the increase in bitterness during oak aging.

Topics: Anisoles; Chromatography, High Pressure Liquid; Humans; Lignans; Molecular Structure; Naphthalenes; Nuclear Magnetic Resonance, Biomolecular; Quercus; Taste; Wine; Wood

The 80% methanolic extract of Euonymus alatus leaves and twigs afforded three new lignans, (-)-threo-4,9,4',9'-tetrahydroxy-3,7,3',5'-tetramethoxy-8-O-8'-neolignan (1), (-)-threo-4,9,4',9'-tetrahydroxy-3,5,7,3'-tetramethoxy-8-O-8'-neolignan (2), (7R,8R,7'R)-(+)-lyoniresinol (3), together with seventeen known lignans (4-20). The structures of 1-20 were elucidated by extensive 1D and 2D spectroscopic methods including (1)H NMR, (13)C NMR, (1)H-(1)H COSY, HMQC, HMBC and NOESY. All the isolated compounds except for dilignans (19 and 20) significantly inhibited nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells.

Topics: Animals; Anisoles; Cell Line; Euonymus; Lignans; Lipopolysaccharides; Macrophages; Magnetic Resonance Spectroscopy; Mice; Molecular Conformation; Naphthalenes; Nitric Oxide; Plant Leaves

To study the chemical constitutents of the 60% ethanol extract of the stems of Sambucus williamsii.. Compounds were isolated and purified by Diaion D101, silica gel,Sephadex LH-20, ODS column chromatography and preparative HPLC. Their structures were identified by spectroscopic methods.. Seven lignans were isolated and identified as erythro-guaiacylglycerol-beta-O-4'-sinapyl ether (1), 1-( 4'-hydroxy-3'-methoxyphenyl) -2- [4"-( 3-hydroxypropyl) -2", 6"-dimethoxyphenoxy] propane-1,3-diol (2), isolariciresinol (3), burselignan (4), lyoniresinol (5), 5-methoxy-isolariciresinol (6), cycloolivil (7).. All these compounds were obtained from this genus for the first time.

Topics: Anisoles; Antineoplastic Agents, Phytogenic; Chromatography, High Pressure Liquid; Lignans; Lignin; Microscopy; Naphthalenes; Naphthols; Plant Stems; Sambucus

Two new compounds, cinnamic aldehyde cyclic d-galactitol 3'R,4'S-acetal (1) and cinnamomumolide (2), along with six known compounds, syringaresinol (3), lyoniresinol (4), 5,7,3'-trimethoxyl-( - )-epicatechin (5), 5,7-dimethoxyl-3',4'-di-O-methylene-( +/- )-epicatechin (6), 2-methoxyl-4-hydroxy cinnamyl aldehyde (7), and glucosyringic acid (8), have been isolated from the dried tender stems of Cinnamomum cassia. Their structures were elucidated based on spectroscopic data. Compound 2 was elucidated as 8-methoxyl-9-hydroxy-3',4'-methylenedioxy-3S,4R-diphenyl butyrolactone, named cinnamomumolide, which exhibited activity in protecting against the injury caused by hydrogen peroxide oxidation on human umbilical vein endothelial cells, with an EC(50) value of 10.7 microM. Compounds 3-8 were isolated from the title plant for the first time.

Topics: 4-Butyrolactone; Anisoles; Cinnamates; Cinnamomum aromaticum; Drugs, Chinese Herbal; Endothelial Cells; Furans; Galactitol; Humans; Hydrogen Peroxide; Lignans; Molecular Structure; Naphthalenes; Oxidation-Reduction; Plant Stems; Umbilical Cord; Wounds and Injuries