Antiallergic principles from Alpinia galanga: structural requirements of phenylpropanoids for inhibition of degranulation and release of TNF-α and IL-4 in RBL-2H3 cells

Glycosidically bound compounds were isolated from the methanol extract of fresh rhizomes of smaller galanga (Alpinia officinarum Hance). Nine glycosides (1-9) were finally obtained by reversed-phase HPLC and their structures were elucidated by MS and NMR analyses. They were the three known glycosides, (1R,3S,4S)-trans-3-hydroxy-1,8-cineole beta-D-glucopyranoside (1), benzyl beta-D-glucopyranoside (3), and 1-O-beta-D-glucopyranosyl-4-allylbenzene (chavicol beta-D-glucopyranoside, 4); and the six novel glycosides, 3-methyl-but-2-en-1-yl beta-D-glucopyranoside (2), 1-hydroxy-2-O-beta-D-glucopyranosyl-4-allylbenzene (5), 1-O-beta-D-glucopyranosyl-2-hydroxy-4-allylbenzene (demethyleugenol beta-D-glucopyranoside, 6), 1-O-(6-O-alpha-L-rhamnopyranosyl-beta-D-glucopyranosyl)-2-hydroxy-4-allylbenzene (demethyleugenol beta-rutinoside, 7), 1-O-(6-O-alpha-L-rhamnopyranosyl-beta-D-glucopyranosyl)-4-allylbenzene (chavicol beta-rutinoside, 8), and 1,2-di-O-beta-D-glucopyranosyl-4-allylbenzene (9). Compounds 2-9 were detected for the first time as constituents of galanga rhizomes.

Isolation and structural elucidation of some glycosides from the rhizomes of smaller galanga (Alpinia officinarum Hance).

The volatile constituents of the aerial parts of Centaurea pelia, C. thessala ssp. drakiensis and C. zuccariniana (Asteraceae) were extracted by steam distillation and analysed by gas chromatography–mass spectroscopy (GC–MS). Their components were represented by a homologous series of alkanes, alkenes, related aliphatic alcohols, aldehydes and ketones, as well as fatty acids and terpenoids. Copyright © 2000 John Wiley & Sons, Ltd.

Volatile constituents of Centaurea pelia DC., C. thessala Hausskn. subsp. drakiensis (Freyn & Sint.) Georg. and C. zuccariniana DC. from Greece

The 80% aqueous acetone extract from the rhizomes of Alpinia galanga showed nitric oxide (NO) production inhibitory activities in mouse peritoneal macrophages. From the aqueous acetone extract, three new 8-9' linked neolignans, galanganal, galanganols A and B, and a sesquineolignan, galanganol C, were isolated together with nine known phenylpropanoids and p-hydroxybenzaldehyde. The structures of new neolignans were determined on the basis of physicochemical and chemical evidence. In addition, the inhibitory effects of the constituents from the rhizomes of A. galanga on NO production induced by lipopolysaccharide in mouse peritoneal macrophages were examined. Among them, galanganal (IC50=68 microM), galanganols B (88 microM) and C (33 microM), 1'S-1'-acetoxychavicol acetate (2.3 microM), 1'S-1'-acetoxyeugenol acetate (11 microM), trans-p-hydroxycinnamaldehyde (ca. 20 microM), trans-p-coumaryl alcohol (72 microM), and trans-p-coumaryl diacetate (19 microM) were found to show inhibitory activity.

https://www.jstage.jst.go.jp/article/cpb/53/6/53_6_625/_pdf

Inhibitors of Nitric Oxide Production from the Rhizomes of Alpinia galanga: Structures of New 8–9′ Linked Neolignans and Sesquineolignan

The methanolic extract from the fresh flowers of Prunus mume exhibited inhibitory effects against aldose reductase and platelet aggregation. From the methanolic extract, two new flavonol oligoglycosides, 2' '-O-acetylrutin and 2' '-O-acetyl-3'-O-methylrutin, and two new polyacylated sucroses, prunoses I and II, were isolated together with 11 known constituents. The structures of 2' '-O-acetylrutin, 2' '-O-acetyl-3'-O-methylrutin, and prunoses I and II were determined on the basis of chemical and physicochemical evidence as quercetin 3-O-alpha-L-rhamnopyranosyl(1-->6)-2' '-O-acetyl-beta-D-glucopyranoside, 3'-O-methylquercetin 3-O-alpha-L-rhamnopyranosyl(1-->6)-2' '-O-acetyl-beta-D-glucopyranoside, 1,4,3',4',6'-penta-O-acetyl-6-O-p-coumaroylsucrose, and 1,3',4',6'-tetra-O-acetyl-6-O-p-coumaroylsucrose, respectively. The flavonol glycosides and prunose I were found to inhibit aldose reductase, while prunoses I and II inhibited platelet aggregation induced by thrombin.

New flavonol oligoglycosides and polyacylated sucroses with inhibitory effects on aldose reductase and platelet aggregation from the flowers of Prunus mume.

Chavicol β-d-glucoside, a phenylpropanoid heteroside, benzyl-β-d-glucoside and glycosidically bound volatiles from subspecies of Cedronella canariensis

Glandular trichomes in form of long stretched tubes are present on the lower leaf side of Quercus robur as shown by scanning electron microscopy. The glands contain an essential oil, which was isolated by steam distillation together with volatile waxy components of the leaves in an amount of 0.025% of fresh leaves. The product of steam distillation was analyzed by GC-MS. Identification of com pounds is based on comparison of their mass spectral data with those of authentic samples in combination with retention indices and MS data using the SeKoMS (Search Kovats Indices and Mass Spectra) Library. Altogether 184 components of the product of steam distillation were separated, 155 of which could be identified, another 7 were tentatively assigned. Three groups of substances according to their chemical composition are found: hexenyl derivatives and some acetals (32%); terpenes including monoterpenes (4% ), sesquiterpenes and diterpenes (21%); and alkane derivatives (35%). The residual 8% consist of benzyl alcohol, com pounds which stem from the degradation of carotenes, and miscellaneous constituents

Glandular Trichomes and the Yolatiles Obtained by Steam Distillation of Quercus robur Leaves

The essential oils of Cedronella canariensis (L.) Webb et Berth, ssp. canariensis and ssp. anisata from Tenerife, La Gomera, Madeira and from a location in South Africa were analyzed in detail by GC, GC-EIMS, GC-CIMS, MID, SC and 13C-NMR. About 210 (ssp. canariensis) and 257 (ssp. anisata) compounds have been identified or at least partly characterized, with monoterpene ketone pinocarvone (>50%) as the most abundant compound of the oil of ssp. canariensis and methyl chavicol (>80%) as the main constituent of the oil of ssp. anisata. The latter was not identified in the ssp. canariensis. For both subspecies, two morphologically different formae were, f. glabra and f. pubescens.

Ralf Engel

Papers

Chavicol β-d-glucoside, a phenylpropanoid heteroside, benzyl-β-d-glucoside and glycosidically bound volatiles from subspecies of Cedronella canariensis

Glandular Trichomes and the Yolatiles Obtained by Steam Distillation of Quercus robur Leaves

Composition of the Essential Oils of Cedronella canariensis (L.) Webb et Berth, ssp. canariensis and ssp. anisata f. glabra and f. pubescens