Acylated anthocyanins from the violet-blue flowers of Orychophragonus violaceus

Three acylated cyanidin 3-sambubioside-5-glucosides (1-3) were isolated from the violet-blue flowers of Orychophragonus violaceus, and their structures were determined by chemical and spectroscopic methods. Two of those acylated anthocyanins (1 and 3) were cyanidin 3-O-[2-O-(2-O-(4-O-(6-O-(4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-xylopyranosyl)-6-O-(4-O-(beta-D-glucopyranosyl)-trans-acyl)-beta-D-glucopyranoside]-5-O-(6-O-malonyl-beta-D-glucopyranoside)s, in which the acyl groups were p-coumaric acid for 1, and sinapic acid for 3, respectively. The last anthocyanin 2 was cyanidin 3-O-[2-O-(2-O-(4-O-(6-O-(4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-xylopyranosyl)-6-O-(4-O-(beta-D-glucopyranosyl)-trans-feruloyl)-beta-D-glucopyranoside]-5-O-beta-D-glucopyranoside. In these flowers, the anthocyanins 2 and 3 were present as dominant pigments, and 1 was obtained in rather small amounts.     

Acylated anthocyanins from the blue-violet flowers of Anemone coronaria

Five polyacylated anthocyanins were isolated from blue-violet flowers of Anemone coronaria 'St. Brigid'. They were identified as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its demalonylated form, delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its cyanidin analog as well as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-(tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside].     

Acylated delphinidin 3-rutinoside-5-glucosides in the flowers of Petunia reitzii

Two acylated anthocyanins were isolated from selected individuals of Petunia reitzii, and identified to be delphinidin 3-O-[6-O-(4-O-(4-O-(6-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-tr ans-p-coumaroyl)-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside]- 5-O-[beta-D-glucopyranoside] and delphinidin 3-O-[6-O-(4-O-(4-O-(beta-D-glucopyranosyl)-trans-p-coumaroyl)-alph a-L-rhamnopyranosyl)-beta-D-glucopyranoside]-5-O-[beta-D-glucopyranoside ]. Nine known anthocyanins were also identified.     

Acylated pelargonidin glycosides in the red-purple flowers of Pharbitis nil.

Four acylated pelargonidin glycosides and pelargonidin 3-sophoroside-5-glucoside were isolated from 23 red-purple cultivars of Pharbitis nil. The acylated anthocyanins were all based on pelargonidin 3-sophoroside-5-glucoside and were identified as the 3-O-[2-O-(beta-D-glucopyranosyl)-6-O-(trans-caffeyl)-beta-D- glucopyranoside]-5-O-(beta-D-glucopyranoside), the 3-O-[2-O-(6-O-(trans-3-O-(beta-D-glucopyranosyl)caffeyl)-beta- D-glucopyranosyl)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), the 3-O-[2-O-(6-O-(trans-3-O-(beta-D-glucopyranosyl)caffeyl)-beta- D-glucopyranosyl)-6-O-(trans-caffeyl)-beta-D-glucopyranoside]-5-O-(beta- D-glucopyranoside); and the 3-O-[2-O-(6-O-(trans-3-O-(beta-D-glucopyranosyl)caffeyl)-beta-D- glucopyranosyl)-6-O-(trans-4-O-(6-O-(trans-3-O-(beta-D- glucopyranosyl)caffeyl)- beta-D-glucopyranosyl)caffeyl)-beta-D-glucopyranoside]-5-O-(beta-D- glucopyranoside). By the analysis of these anthocyanin constituents variously in 23 cultivars, it was found that the red flower colour gradually changed into more bluish colour with increasing numbers of caffeic acid residues in the acylated pelargonidin glycosides. The stabilities of these anthocyanins increased in the order of increasing caffeyl substitution.     

Triacylated cyanidin 3-(3X-glucosylsambubioside)-5-glucosides from the flowers of Malcolmia maritima

Three acylated cyanidin 3-(3(X)-glucosylsambubioside)-5-glucosides (1-3) and one non-acylated cyanidin 3-(3(X)-glucosylsambubioside)-5-glucoside (4) were isolated from the purple-violet or violet flowers and purple stems of Malcolmia maritima (L.) R. Br (the Cruciferae), and their structures were determined by chemical and spectroscopic methods. In the flowers of this plant, pigment 1 was determined to be cyanidin 3-O-[2-O-(2-O-(trans-sinapoyl)-3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-6-O-(trans-p-coumaroyl)-beta-D-glucopyranoside]-5-O-[6-O-(malonyl)-(beta-D-glucopyranoside) as a major pigment, and a minor pigment 2 was determined to be the cis-p-coumaroyl isomer of pigment 1. In the stems, pigment 3 was determined to be cyanidin 3-O-[2-O-(2-O-(trans-sinapoyl)-3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-6-O-(trans-p-coumaroyl)-beta-d-glucopyranoside]-5-O-(beta-D-glucopyranoside) as a major anthocyanin, and also a non-acylated anthocyanin, cyanidin 3-O-[2-O-(3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside) was determined to be a minor pigment (pigment 4). In this study, it was established that the acylation-enzymes of malonic acid has important roles for the acylation of 5-glucose residues of these anthocyanins in the flower-tissues of M. maritima; however, the similar enzymatic reactions seemed to be inhibited or lacking in the stem-tissues.     

7-Polyacylated delphinidin 3,7-diglucosides from the blue flowers of Leschenaultia cv. Violet Lena

The triacyl anthocyanins, Leschenaultia blue anthocyanins 1 and 2 (LBAs 1 and 2) were isolated from the blue flowers of Leschenaultia R. Br. cv. Violet Lena (Goodeniaceae), in which LBA 1 was present as a dominant pigment. The structure of LBA 1 was elucidated to be delphinidin 3-O-[6-O-(malonyl)-beta-D-glucopyranoside]-7-O-[6-O-(4-O-(6-O-(4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranoside] by application of chemical and spectroscopic methods. Since LAB 2 was isolated in small amount, its structure was tentatively assigned as either delphinidin 3-(malonylglucoside)-7-[(glucosyl-p-coumaroyl)-(glucosylcaffeoyl)-glucoside] or delphinidin 3-(malonyl-glucoside)-7-[(glucosyl-caffeoyl)(glucosyl-p-coumaroyl)-glucoside]. This is the first report of the occurrence of 7-polyacylated anthocyanins in the family of Goodeniaceae, although others have been found in the families of the Ranunculaceae, Campanulaceae, and Compositae. Moreover, delphinidin 3-glycoside-7-di-(glucosylcaffeoyl)-glucoside has been reported only in the flowers of Platycodon grandiflorum (Campanulaceae). From a chemotaxonomical viewpoint, the Goodeniaceae may be closely related to the Campanulaceae.     

Anthocyanins from the scarlet flowers of Anemone coronaria

Three acylated anthocyanins were isolated from the scarlet flowers of Anemone coronaria 'St. Brigid Red' along with a known pigment, pelargonidin 3-lathyroside. The structures of the acylated pigments were based on a pelargonidin 3-lathyroside skeleton acylated at different positions with malonic acid. The first pigment was identified as pelargonidin 3-O-[2-(beta-D-xylopyranosyl)-6-O-(malonyl)-beta-D-galactopyranoside], the second was pelargonidin 3-O-[2-O-(beta-D-xylopyranosyl)-6-O-(methyl-malonyl)-beta-D-galactopyranoside], and the third was (6'-O-(pelargonidin 3-O-[2'-O-(beta-D-xylopyranosyl)-beta-D-galactopyranosyl]))((4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-O-tartatryl)malonate.     

Two triacylated and tetraglucosylated anthocyanins from Ipomoea asarifolia flowers

Two triacylated and tetraglucosylated anthocyanins derived from cyanidin were isolated from the flowers of Ipomoea asarifolia and their structures elucidated using chemical, GC, MS and NMR methods (1H and 13C, TOCSY-1D, DQF-COSY, DIFFNOE and HMBC). These complex pigments were found to consist of cyanidin 3-O-[2-O-(6-O-E-caffeoyl-beta-D-glucopyranosyl)]-[6-O-[4-O-(6-O-E-3,5-dihydroxycinnamoyl-beta-D-glucopyranosyl)-E-caffeoyl]-beta-D-glucopyranosyl]-5-O-beta-D-glucopyranoside and cyanidin 3-O-[2-O-(6-O-E-p-coumaroyl-beta-D-glucopyranosyl)]-[6-O-[4-O-(6-O-E-p-coumaroyl-beta-D-glucopyranosyl)-E-caffeoyl]-beta-D-glucopyranosyl]-5-O-beta-D-glucopyranoside.     

The structure of the major anthocyanin in Arabidopsis thaliana

The major anthocyanin in the leaves and stems of Arabidopsis thaliana has been isolated and shown to be cyanidin 3-O-[2-O(2-O-(sinapoyl)-beta-D-xylopyranosyl)-6-O-(4-O-(beta-D-glucopyranosyl)-p-coumaroyl-beta-D-glucopyranoside] 5-O-[6-O-(malonyl) beta-D-glucopyranoside]. This anthocyanin is a glucosylated version of one of the anthocyanins found in the flowers of the closely related Matthiola incana.     

Glucuronide triterpene saponins from Bersama engleriana

Five 3-O-glucuronide triterpene saponins (1-5) were isolated from the stem bark of Bersama engleriana Gurke along with two known saponins, polyscias saponin C and aralia saponin 15, and one major C-glycoside xanthone, mangiferin. The structures of the saponins were established mainly by means of spectroscopic methods (one- and two-dimensional NMR spectroscopy as well as FAB-, HRESI-mass spectrometry) as 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-betulinic acid (1), 3-O-[beta-D-glucopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-beta-D-glucuronopyranosyl]-oleanolic acid (2), 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucuronopyranosyl]-28-O-[beta-D-xylopyranosyl-(1-->6)-beta-d-glucopyranosyl]-oleanolic acid (3), 3-O-[beta-D-galactopyranosyl-(1-->3)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl]-oleanolic acid (4), and 3-O-[beta-d-glucopyranosyl-(1-->3)-beta-D-galactopyranosyl-(1-->3)-beta-D-glucuronopyranosyl]-28-O-[beta-d-xylopyranosyl-(1-->6)-beta-D-glucopyranosyl]-oleanolic acid (5).     

Triterpenoid saponins from Oreopanax guatemalensis

Seven oleanane-type saponins were isolated from the leaves and stems of Oreopanax guatemalensis, together with ten known saponins of lupane and oleanane types. The new saponins were respectively characterized as 3-O-alpha-L-arabinopyranosyl echinocystic acid 28-O-[alpha- L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester, 3-O-beta-D-glucopyranosyl 3beta-hydroxy olean-11,13(18)-dien-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta- D-glucopyranosyl]ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl]3beta-hydroxy olean-11,13(18)-dien-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]3beta, 23 dihydroxy olean-18-en-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-6-O-acetyl glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl] hederagenin 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-[beta-D-xylopyranosyl-(1-->2 )-]beta-D-glucopyranosyl]ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]hederagenin 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-[beta-D-glucopyranosyl-(1-->2)-]beta-D-glucopyranosyl] ester and 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl] hederagenin 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-[alpha-L-arabinofuranosyl-(1-->2)]-beta-D-glucopyranosyl] ester. The structures were determined by spectral analyses. The NMR assignments were made by means of HOHAHA, 1H-1H COSY, HMQC, HMBC spectra and NOE difference studies.     

Five saponins from the root bark of Aralia elata

Five saponins, 3-O-[beta-D-glucopyranosyl (1-->2)-[beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl]-oleanolic acid 28-O-beta-D-glucopyranosyl ester (aralia-saponin V), 3-O-[beta-D-glucopyranosyl (1-->2)-[beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl]-echinocystic acid 28-O-beta-D-glucopyranosyl ester (aralia-saponin VI), 3-O-beta-D-glucopyranosyl (1-->2)-[beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl]-hederagenin 28-O-beta-D-glucopyranosyl ester (aralia-saponin VII), 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl]-caulophyllogenin 28-O-beta-D-glucopyranosyl ester (aralia-saponin VIII), 3-O-[beta-D-glucopyranosyl (1-->2)-[beta-D-glucopyranosyl(1-->3)]-alpha-L-arabinopyranosyl]-hederagenin 28-O-beta-D-glucopyranosyl ester (aralia-saponin IX), were isolated from the root bark of Aralia elata (Miq.) Seem., together with four known compounds. Their structures were determined on the basis of chemical and spectroscopic methods.     

Triterpenoid saponins from Fagonia cretica

Four new triterpenoid saponins were isolated and identified from the aerial parts of Fagonia cretica. They were characterized as 3-O-[beta-D-glucopyranosyl (1-->2)-alpha-L-arabinopyranosyl] hederagenin 28-O-beta-D-glucopyranosyl ester, 3-O-[beta-D-glucopyranosyl (1-->2)-alpha-L-arabinopyranosyl] oleanolic acid 28-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] ester, 3-O-[beta-D-glucopyranosyl (1-->2)-alpha-L-arabinopyranosyl] 27-hydroxy oleanolic acid 28-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] ester and 3beta-O-[beta-D-glucopyranosyl (1-->2)-alpha-L-arabinopyranosyl] olean-12-en-27-al-28-oic acid 28-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] ester. The structures of the saponins were assigned by spectral analyses (FABMS, 1H, 13C NMR, 1H-1H COSY, TOCSY, HMQC and HMBC spectra) and NOE experiments. To the best of our knowledge the genin 3beta hydroxy olean-12-en-27-al-28-oic acid is new.     

Absorption of acylated anthocyanins in rats and humans after ingesting an extract of Ipomoea batatas purple sweet potato tuber

We evaluated the absorbability of anthocyanins in humans and rats administered with a beverage prepared from an extract of the tuber of purple sweet potato (Ipomoea batatas Cultivar Ayamurasaki), or with an anthocyanin concentrate. Two major anthocyanin components, cyanidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranosyl)-beta-D-glucopyranoside)-5-O-beta-D-glucopyranoside) and peonidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranosyl)-beta-D-glucopyranoside)-5-O-beta-D-glucopyranoside), were detected in the plasma and urine of both rats and humans by HPLC or liquid chromatography/mass spectrometry (LC/MS). The plasma concentration of anthocyanins in humans reached a maximum 90 minutes after ingestion, and the recovery of anthocyanins in the urine was estimated as 0.01-0.03%. These results indicate that acylated anthocyanins could be selectively absorbed after ingesting food.     

27-Nor-triterpenoid glycosides from Mitragyna inermis

From the bark of Mitragyna inermis, two 27-nor-triterpenoid glycosides, named inermiside I (1) and II (2), were isolated and their structures determined based on extensive 2D-NMR and MS spectral analysis as 6-deoxy-beta-D-glucopyranosyl-[3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]-pyrocincholate and 6-deoxy-beta-D-glucopyranosyl-pyrocincholate, respectively. In addition, the known quinovic acid (6), 3-O-[beta-D-glucopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl]-quinovoic acid (3),beta-D-glucopyranosyl-[3-O-(beta-D-glucopyranosyl)]-quinoviate (4) and cytotoxic 3-O-(beta-D-6-deoxy-glucopyranosyl)-quinovic acid (5) were also isolated.     

Acylated anthocyanins from red radish (Raphanus sativus L.)

Twelve acylated anthocyanins were isolated from the red radish (Raphanus sativus L.) and their structures were determined by spectroscopic analyses. Six of these were identified as pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-beta-D-glucopyranosyl]-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-caffeoyl-2-O-(6-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-p-coumaroyl-2-O-(6-(E)-caffeoyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-(6-(E)-caffeoyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-p-coumaroyl-2-O-(6-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), and pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-(2-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside).     

Triterpenoid saponins from the stem bark of Elattostachys apetala

Six new triterpenoid saponins have been isolated from the stem bark of Elattostachys apetala together with four known triterpenoid saponins. Three of these new compounds are glycosides of a newly described genin, 29-hydroxyhederagenin (1). On the basis of spectral evidence, the structures of the new saponins were concluded to be alpha-hederin 28-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl] ester (2), sapindoside B 28-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl] ester (3), 3-O-beta-D-xylopyranosyl astrantiasaponin VII (4), 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]-28-O-[beta-D-glucopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyranosyl]-29-hydroxyhederagenin (5), 3-O-[alpha-L-arabinopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]-28-O-[beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->6)]-beta-D-glucopyranosyl]-29-hydroxyhederagenin (6), and 3-O-[beta-D-xylopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]-28-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-gluco pyranosyl-(1-->6)]-beta-D-glucopyranosyl]-29-hydroxyhederagenin (7).     

Steroidal saponins from the fruits of Asparagus racemosus

Three steroidal saponins, racemosides A (1), B (2) and C (3), were isolated from the methanolic extract of the fruits of Asparagus racemosus, and characterized as (25S)-5beta-spirostan-3beta-ol-3-O-{beta-D- glucopyranosyl (1-->6)-[alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->4)]-beta-D-glucopyranoside}, (25S)-5beta-spirostan-3beta-ol-3-O-alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside and (25S)-5beta-spirostan-3beta-ol-3-O-{alpha-L-rhamnopyranosyl-(1-->6)-[alpha-L-rhamnopyranosyl (1-->4)]-beta-D-glucopyranoside}, respectively, by spectrometric analysis and some chemical strategies.     

Bioactive flavonoids and saponins from Climacoptera obtusifolia

Two bidesmosidic saponins were isolated from Climacoptera obtusifolia (Chenopodiaceae) and their structures were determined as gypsogenin 3-O-[beta-D-xylopyranosyl-(1-->3)-beta-D-glucopyranoside]-28-O-{beta-D-glucopyranosyl} ester (1) and hederagenin 3-O-[beta-D-xylopyranosyl-(1-->3)-beta-D-glucopyranoside]-28-O-[beta-D-glucopyranosyl} ester (2), by spectroscopic methods. Two known compounds, isorhamnetin 3-O-beta-D-glucopyranoside (3), and isorhamnetin 3-O-[alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (4) were also isolated for the first time from this plant. Compounds 1-4 were tested in various immunomodulatory assays. Compound 2 suppressed (92%) the reactive oxygen species (ROS) production on mononuclear cells in luminol-based chemiluminescence (CL) assay at a higher concentration (50 microg/mL). Compounds 3 and 4 demonstrated a strong inhibition on ROS production in the oxidative burst activity of whole blood, neutrophils, and mononuclear cells. Additionally compounds 3 and 4 also suppressed PHA T-cell proliferation with no cytotoxic effects.     

In vivo anti-inflammatory activity of saponins from Bupleurum rotundifolium

Seven oleanane-type triterpene saponins were isolated from the methanolic extract of the aerial parts of Bupleurum rotundifolium. They were identified on the basis of their spectral data as 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl] echinocystic acid (saponin 1), 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-fucopyranosyl] 11-methoxy-primulagenin A (saponin 2), rotundioside E (saponin 3), rotundioside F (saponin 4), 3beta-sulfate, 28-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl] ester of primulagenin A (saponin 5), rotundioside C (saponin 6) and 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-fucopyranosyl] 11-methoxy-16beta,21alpha,28-trihydroxyolean-12-ene (saponin 7). All these saponins proved to be effective against TPA-induced ear edema in mice. Their ID50 were determined to be 248, 288, 128, 99 and 297 nmol/ear for saponin 1, 2, 3, 4 and 6, respectively. Saponins 3 and 6 were also active on a TPA multiple-dose model of skin chronic inflammation.