Faba Bean (Vicia faba L. minor) Bitterness: An Untargeted Metabolomic Approach to Highlight the Impact of the Non-Volatile Fraction.

In the context of climate change, faba beans are an interesting alternative to animal proteins but are characterised by off-notes and bitterness that decrease consumer acceptability. However, research on pulse bitterness is often limited to soybeans and peas. This study aimed to highlight potential bitter non-volatile compounds in faba beans. First, the bitterness of flours and air-classified fractions (starch and protein) of three faba bean cultivars was evaluated by a trained panel. The fractions from the high-alkaloid cultivars and the protein fractions exhibited higher bitter intensity. Second, an untargeted metabolomic approach using ultra-high-performance liquid chromatography-diode array detector-tandem-high resolution mass spectrometry (UHPLC-DAD-HRMS) was correlated with the bitter perception of the fractions. Third, 42 tentatively identified non-volatile compounds were associated with faba bean bitterness by correlated sensory and metabolomic data. These compounds mainly belonged to different chemical classes such as alkaloids, amino acids, phenolic compounds, organic acids, and terpenoids. This research provided a better understanding of the molecules responsible for bitterness in faba beans and the impact of cultivar and air-classification on the bitter content. The bitter character of these highlighted compounds needs to be confirmed by sensory and/or cellular analyses to identify removal or masking strategies.

Oleanolic Acid Glycosides from Scabiosa caucasica and Scabiosa ochroleuca: Structural Analysis and Cytotoxicity.

In the field of research on medicinal plants from the Armenian flora, the phytochemical study of two Scabiosa L. species, S. caucasica M. Bieb. and S. ochroleuca L. (Caprifoliaceae), has led to the isolation of five previously undescribed oleanolic acid glycosides from an aqueous-ethanolic extract of the roots: 3-O-α-L-rhamnopyranosyl-(1→3)-ß-D-glucopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyloleanolic acid 28-O-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranosyl ester, 3-O-ß-D-xylopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→4)]-ß-D-glucopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyloleanolic acid 28-O-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranosyl ester, 3-O-ß-D-xylopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→4)]-ß-D-glucopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyloleanolic acid, 3-O-ß-D-xylopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→4)]-ß-D-xylopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyloleanolic acid 28-O-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranosyl ester, 3-O-α-L-rhamnopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-glucopyranosyl-(1→4)-ß-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyloleanolic acid 28-O-ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranosyl ester. Their full structural elucidation required extensive 1D and 2D NMR experiments, as well as mass spectrometry analysis. For the biological activity of the bidesmosidic saponins and the monodesmosidic saponin, their cytotoxicity on a mouse colon cancer cell line (MC-38) was evaluated.

Activation of a Sweet Taste Receptor by Oleanane-Type Glycosides from Wisteria sinensis.

The phytochemical study of Wisteria sinensis (Sims) DC. (Fabaceae), commonly known as the Chinese Wisteria, led to the isolation of seven oleanane-type glycosides from an aqueous-ethanolic extract of the roots. Among the seven isolated saponins, two have never been reported before: 3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-glucopyranosyl-(1→2)-ß-D-glucuronopyranosyl-22-O-acetylolean-12-ene-3ß,16ß,22ß,30-tetrol, and 3-O-ß-D-xylopyranosyl-(1→2)-ß-D-glucuronopyranosylwistariasapogenol A. Based on the close structures between the saponins from W. sinensis, and the glycyrrhizin from licorice, the stimulation of the sweet taste receptor TAS1R2/TAS1R3 by these glycosides was evaluated.

An Overview of Traditional Uses, Phytochemical Compositions and Biological Activities of Edible Fruits of European and Asian Cornus Species.

Cornus species are widely distributed in central and southern Europe, east Africa, southwest Asia, and America. Several species are known for edible fruits, especially Cornus mas and Cornus officinalis. These delicious fruits, characterized by their remarkable nutritional and biological values, are widely used in traditional medicine. In contrast to the other edible Cornus species, C. mas and C. officinalis are the most studied for which little information is available on the main phytochemicals and their biological activities. Fruits are characterised by several classes of secondary metabolites, such as flavonoids, phenolic acids, lignans, anthocyanins, tannins, triterpenoids, and iridoids. The available phytochemical data show that the different classes of metabolites have not been systematically studied. However, these edible species are all worthy of interest because similarities have been found. Thus, this review describes the traditional uses of Cornus species common in Europe and Asia, a detailed classification of the bioactive compounds that characterize the fruits, and their beneficial health effects. Cornus species are a rich source of phytochemicals with nutritional and functional properties that justify the growing interest in these berries, not only for applications in the food industry but also useful for their medicinal properties.

Oleanane-type glycosides isolated from the trunk barks of the Central African tree Millettia laurentii.

Seven previously undescribed oleanane-type glycosides were isolated from the trunk barks of a Central African tree named Millettia laurentii De Wild (Fabaceae). After the extraction from the barks, the isolation and purification of these compounds were achieved using various solid/liquid chromatographic methods. Their structures were established mainly by 1D and 2D NMR (COSY, TOCSY, ROESY, HSQC, HMBC) and mass spectrometry (ESI-MS), as 3-O-ß-D-glucuronopyranosyl-(1 â†’ 2)-ß-D-glucuronopyranosylechinocystic acid, 3-O-ß-D-apiofuranosyl-(1 â†’ 3)-ß-D-glucuronopyranosyl-(1 â†’ 2)-ß-D-glucuronopyranosylechinocystic acid, 3-O-ß-D-apiofuranosyl-(1 â†’ 3)-ß-D-galactopyranosyl-(1 â†’ 2)-ß-D-glucuronopyranosylechinocystic acid, 3-O-ß-D-apiofuranosyl-(1 â†’ 3)-[ß-d-xylopyranosyl-(1 â†’ 2)]-ß-D-galactopyranosyl-(1 â†’ 2)-ß-D-glucuronopyranosylechinocystic acid, 3-O-ß-D-apiofuranosyl-(1 â†’ 3)-[α-L-arabinofuranosyl-(1 â†’ 2)]-ß-D-galactopyranosyl-(1 â†’ 2)-ß-D-glucuronopyranosylechinocystic acid, 3-O-α-L-arabinofuranosyl-(1 â†’ 2)-ß-D-galactopyranosyl-(1 â†’ 2)-ß-D-glucuronopyranosyloleanolic acid, 3-O-ß-D-apiofuranosyl-(1 â†’ 3)-[α-L-arabinofuranosyl-(1 â†’ 2)]-ß-D-galactopyranosyl-(1 â†’ 2)-ß-D-glucuronopyranosyloleanolic acid. In addition, the cytotoxicity of six glycosides among the isolated ones, was evaluated against 4 T1 cell line from a mouse mammary gland tissue, using MTS method.

Triterpenoid Saponins from the Cultivar "Green Elf" of Pittosporum tenuifolium.

Four oleanane-type glycosides were isolated from a horticultural cultivar "Green Elf" of the endemic Pittosporum tenuifolium (Pittosporaceae) from New Zealand: three acylated barringtogenol C glycosides from the leaves, with two previously undescribed 3-O-ß-d-glucopyranosyl-(1→2)-[α-l-arabinopyranosyl-(1→3)]-ß-d-glucuronopyranosyl-21-O-angeloyl-28-O-acetylbarringtogenol C, 3-O-ß-d-galactopyranosyl-(1→2)-[α-l-arabinopyranosyl-(1→3)]-ß-d-glucuronopyranosyl-21-O-angeloyl-28-O-acetylbarringtogenol C, and the known 3-O-ß-d-glucopyranosyl-(1→2)-[α-l-arabinopyranosyl-(1→3)]-ß-d-glucuronopyranosyl-21-O-angeloyl-28-O-acetylbarringtogenol C (Eryngioside L). From the roots, the known 3-O-ß-d-glucopyranosyl-(1→2)-ß-d-galactopyranosyl-(1→2)-ß-d-glucuronopyranosyloleanolic acid (Sandrosaponin X) was identified. Their structures were elucidated by spectroscopic methods including 1D- and 2D-NMR experiments and mass spectrometry (ESI-MS). According to their structural similarities with gymnemic acids, the inhibitory activities on the sweet taste TAS1R2/TAS1R3 receptor of an aqueous ethanolic extract of the leaves and roots, a crude saponin mixture, 3-O-ß-d-glucopyranosyl-(1→2)-[α-l-arabinopyranosyl-(1→3)]-ß-d-glucuronopyranosyl-21-O-angeloyl-28-O-acetylbarringtogenol C, and Eryngioside L were evaluated.

Steroidal glycosides from the Vietnamese cultivar Cordyline fruticosa "Fairchild red".

A phytochemical study of Cordyline fruticosa "Fairchild red" (Asparagaceae) from Vietnam, led to the isolation of fourteen steroidal glycosides, including twelve previously undescribed along with two known ones. Ten compounds were obtained by successive solid/liquid chromatographic methods from an aqueous-ethanolic extract of the roots, and four from the aerial parts. Their structures were elucidated mainly by spectroscopic analysis 2D NMR and mass spectroscopy (ESI-MS), as spirostanol glycosides, 5α-spirost-25(27)-ene-1ß,3ß,4α-triol 1-O-ß-D-fucopyranoside, 5α-spirost-(25)27-ene-1ß,3ß,4α-triol 1-O-ß-D-xylopyranoside, 5α-spirost-(25)27-ene-1ß,3ß,4α-triol 1-O-α-L-rhamnopyranosyl-(1 â†’ 2)-ß-D-fucopyranoside, 5α-spirost-(25)27-ene-1ß,3ß,4α-triol 1-O-α-L-rhamnopyranosyl-(1 â†’ 2)-(4-O-sulfo)-ß-D-fucopyranoside, 5α-spirost-25(27)-ene-1ß,3ß-diol 1-O-α-L-rhamnopyranosyl-(1 â†’ 2)-ß-D-fucopyranoside, and 5α-spirost-25(27)-ene-1ß,3ß-diol 1-O-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranoside. Furostanol glycosides were also isolated as 26-O-ß-D-glucopyranosyl-5α-furost-(25)27-ene-1ß,3ß,4α,22α,26-pentol 1-O-ß-D-fucopyranoside, 26-O-ß-D-glucopyranosyl-22α-methoxy-5α-furost-(25)27-ene-1ß,3ß,4α,26-tetrol 1-O-ß-D-fucopyranoside, 26-O-ß-D-glucopyranosyl-5α-furost-(25)27-ene-1ß,3ß,22α,26-tetrol 1-O-ß-D-glucopyranoside, 26-O-ß-D-glucopyranosyl-5α-furost-(25)27-ene-1ß,3ß,22α,26-tetrol 1-O-α-L-rhamnopyranosyl-(1 â†’ 2)-ß-D-glucopyranoside, 26-O-ß-D-glucopyranosyl-5α-furost-(25)27-ene-1ß,3ß,22α,26-tetrol 1-O-α-L-rhamnopyranosyl-(1 â†’ 2)-ß-D-fucopyranoside, and 26-O-ß-D-glucopyranosyl-22α-methoxy-5α-furost-(25)27-ene-1ß,3ß,26-triol 1-O-α-L-rhamnopyranosyl-(1 â†’ 2)-ß-D-fucopyranoside. All the isolated compounds were further evaluated for their cytotoxicity against 4T1 cell line, from a mouse mammary gland tissue, using MTS method.

Anti-phytopathogen terpenoid glycosides from the root bark of Chytranthus macrobotrys and Radlkofera calodendron.

Chytranthus macrobotrys and Radlkofera calodendron are two Sapindaceae characterized by a lack of phytochemical data. Both root barks from the two Sapindaceae species were processed by ethanol extraction followed by the isolation of their primary constituents by liquid chromatography. This process yielded four previously undescribed terpenoid glycosides together with eight known analogues. Extracts and isolated compounds from C. macrobotrys and R. calodendron were then screened for antimicrobial activity against fifteen phytopathogens. The biological screening also involved extracts and pure compounds from Blighia unijugata and Blighia welwitschii, two Sapindaceae previously studied by our group. Phytopathogens were chosen based on their economic impact on agriculture worldwide. The selection was composed primarily of fungal species including; Pyricularia oryzae, Gaeumannomyces graminis var. tritici, Zymoseptoria tritici, Fusarium oxysporum, Botrytis cinerea, Pythium spp., Trichoderma spp. and Rhizoctonia solani. Furthermore, pure terpenoid glycosides were tested for the first time against wood-inhabiting phytopathogens such as; Phaeomoniella chlamydospora, Phaeoacremonium minimum, Fomitiporia mediterranea, Eutype lata and Xylella fastidiosa. Raw extracts exhibited different levels of activity dependent on the organism. Some pure compounds, including 3-O-α-L-arabinopyranosyl-(1 â†’ 4)-ß-D-xylopyranosyl-(1 â†’ 3)-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranosylhederagenin (α-hederin), 3-O-ß-D-glucopyranosyl-(1 â†’ 3)-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranosylhederagenin (macranthoside A) and 3-O-α-L-arabinopyranosyl-(1 â†’ 3)-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranosylhederagenin (clemontanoside C), exhibited significant growth inhibitions on Pyricularia oryzae, Gaeumannomyces graminis var. tritici, Fomitiporia mediterranea and Zymoseptoria tritici. Monodesmoside triterpene saponins, in particular, exhibited MIC (IC100) values as low as 25 µg/ml and IC50 values as low as 10 µg/ml against these phytopathogens. Structure-activity relationships, as well as plant-microbe interactions, were discussed.

Triterpene glycosides from Blighia welwitschii and evaluation of their antibody recognition capacity in multiple sclerosis.

Multiple sclerosis (MS) in a multifactorial autoimmune disease in which reliable biomarkers are needed for therapeutic monitoring and diagnosis. Autoantibodies (autoAbs) are known biomarker candidates although their detection in biological fluids requires a thorough characterization of their associated antigens. Over the past twenty years, a reverse chemical-based approach aiming to screen putative autoantigens has underlined the role of glycans, in particular glucose, in MS. Despite the progress achieved, a lack of consensus regarding the nature of innate antigens as well as difficulties proposing new synthetic glucose-based structures have proved to be obstacles. Here is proposed a strategy to extend the current methodology to the field of natural glycosides, in order to dramatically increase the diversity of glycans that could be tested. Triterpene saponins from the Sapindaceace family represent an optimal starting material as their abundant description in the literature has revealed a prevalence of glucose-based oligosaccharides. Blighia welwitschii (Sapindaceae) was thus selected as a case study and twelve triterpene saponins were isolated and characterized. Their structures were elucidated on the basis of 1D and 2D NMR as well as mass spectrometry, revealing seven undescribed compounds. A selection of natural glycosides exhibiting various oligosaccharide moieties were then tested as antigens in enzyme-linked immunosorbent assay (ELISA) to recognize IgM antibodies (Abs) in MS patients' sera. Immunoassay results indicated a correlation between the glycan structures and their antibody recognition capacity, allowing the determination of structure-activity relationships that were coherent with previous studies. This approach might help to identify sugar epitopes putatively involved in MS pathogenesis, which remains poorly understood.

A review on the phytopharmacological studies of the genus Polygala.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Polygala, the most representative genus of the Polygalaceae family, comprises more than 600 species from all over the world of which around 40 are distributed in China, some of them, being used in the Traditional Chinese Medicine system. AIM OF THE REVIEW: We intend to discuss the current knowledge about the traditional uses, and the newest phytochemical and pharmacological achievements with tentative elucidation of the mechanism of action on the genus Polygala covering the period 2013-2019 to provide a scientific support to the traditional uses, and to critically analyze the reported studies to obtain new insights for further researches. MATERIALS AND METHODS: The data were systematically collected from the scientific electronic data bases including SciFinder, Scopus, Elsevier, PubMed and Google Scholar. RESULTS: This literature overview reported several traditional uses of different species of Polygala, mainly against wounds, inflammation, cardiovascular and central nervous system disorders. P. altomontana, P caudata, P. flavescens, P. glomerata, P. japonica, P. molluginifolia, P. sibirica, P. tenuifolia are the main species which have been studied in the last few years. Phytochemical studies showed that they contain triterpene saponins, triterpenes, terpenoids, xanthones, flavonoids, coumarins, oligosaccharide esters, styryl-pyrones, benzophenones, and polysaccharides. Pharmacological in vitro and in vivo studies and proposal of the mechanisms of action indicated that pure constituents and extracts of Polygala ssp exhibited significant anti-inflammatory, neuroprotective, antiischemic, antidepressant, sedative, analgesic, antiatherosclerosis, antitumor and enzyme inhibitory properties. CONCLUSION: This review on traditional uses and phytopharmacological potential of the genus Polygala revealed updated insights which can be explored for further mechanism-based pharmacological activities and structure/activity relationships studies and a better comprehension of the development of Chinese medicine preparations. However some pharmacological studies showed several gaps such as incomplete methodologies and ambiguous findings. More high scientific quality preclinical studies with pharmacokinetic considerations will be required in the future to assess the traditional uses of some species of this genus. This might lead to efficacy and safety issues in clinical trials and to potential medicinal applications.

Cytotoxic glycosides from the roots of Weigela x "Bristol Ruby".

Seven oleanane-type glycosides were extracted and isolated by various chromatographic methods from the roots of Weigela x "Bristol Ruby" (1-7), six previously undescribed (1-6) and a known one (7). Their structures were assigned by spectroscopic analysis mainly 2D NMR and mass spectrometry (ESIMS). Selected triterpenoid glycosides (1-3, 6, 7) displayed a good cytotoxic activity against a mouse colon cancer cell line CT26.

Hederagenin glycosides from the fruits of Blighia unijugata.

A phytochemical investigation of Blighia unijugata led to the isolation of eleven hederagenin glycosides. Among these compounds, six are previously undescribed, two are described in their native forms for the first time and three are known whereas firstly isolated from Blighia unijugata. The structure of the undescribed compounds was elucidated on the basis of 2D NMR and mass spectrometry analyses as 3-O-ß-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-ß-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-3-O-acetyl-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-ß-D-glucopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-ß-D-xylopyranosyl-(1 → 3)-ß-D-xylopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-ß-D-xylopyranosyl-(1 → 3)-ß-D-xylopyranosyl-(1 → 4)-3-O-acetyl-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-arabinopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-ß-D-glucopyranosyl-(1 → 6)-ß-D-glucopyranosyl ester, 3-O-α-L-arabinopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-ß-D-glucopyranosyl ester and 3-O-ß-D-xylopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-ß-D-glucopyranosyl ester. These results revealed the existence of several conserved structural features that could be used as chemotaxonomic markers for the Blighia genus such as the glycosidic sequence 3-O-α-L-arabinopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl, the occurrence of 3-O-acetylated ß-D-glucopyranosyl units and the systematic presence of hederagenin as aglycone.

Steroidal glycosides from Ornithogalum dubium Houtt.

The phytochemical study of Ornithogalum dubium Houtt. (Asparagaceae) led to the isolation of five undescribed steroidal glycosides together with two known ones. Their structures were established by using NMR analysis and mass spectrometry as (25R)-3ß-hydroxyspirost-5-en-1ß-yl O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside, (25S)-3ß-hydroxyspirost-5-en-1ß-yl O-ß-D-glucopyranosyl-(1 → 6)-ß-D-glucopyranoside, (22S)-16ß-[(α-L-rhamnopyranosyl)oxy]-22-hydroxycholest-5-en-3ß-yl O-ß-D-glucopyranosyl-(1 → 4)-ß-D-glucopyranoside, (22S,23S)-1ß,3ß,11α,16ß,23-pentahydroxy-5α-cholest-24-en-22ß-yl ß-D-glucopyranoside, (22S,23S)-3ß-[(ß-D-glucopyranosyl)oxy]-22,23-dihydroxy-5α-cholest-24-en-16ß-yl O-α-L-rhamnopyranosyl)-(1 → 4)-ß-D-glucopyranoside. Their cytotoxic activities against two human cells, a lung carcinoma A-549 and a promyelocytic leukemia HL-60 cell lines, were evaluated by using the XTT method. The results showed no significant cytotoxicity on the tested cells. The influence of the potentiation of cisplatin cytotoxicity in A-549 cells was also investigated and a slight effect was observed only for the (25R) spirostane-type derivative.

Terpenoid glycosides from the root's barks of Eriocoelum microspermum Radlk. ex Engl.

Eight undescribed triterpenoid saponins together with a known one, and two undescribed sesquiterpene glycosides were isolated from root's barks of Eriocoelum microspermum. Their structures were elucidated by spectroscopic methods including 1D and 2D experiments in combinaison with mass spectrometry as 3-O-α-L-rhamnopyranosyl-(1 → 3)-[α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 3)-[ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 3)-[ß-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 4)-[α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin 28-O-ß-D-glucopyranosyl ester, 3-O-α-L-rhamnopyranosyl-(1 → 3)-ß-D-xylopyranosyl-(1 → 4)-ß-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-ß-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-ß-D-xylopyranosyl-(1 → 4)-α-L-arabinopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-ß-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 1-O-{ß-D-xylopyranosyl-(1 → 3)-[α-L-rhamnopyranosyl-(1 → 2)]-ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 6)}-[ß-D-xylopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-ß-D-glucopyranosyl-(2E,6E)-farnes-1-ol, 1-O-{ß-D-glucopyranosyl-(1 → 3)-[α-L-rhamnopyranosyl-(1 → 2)]-ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 6)}-[ß-D-xylopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-ß-D-glucopyranosyl-(2E,6E)-farnes-1-ol. These results represent a contribution to the chemotaxonomy of the genus Eriocoelum highlighting farnesol glycosides as chemotaxonomic markers of the subfamily of Sapindoideae in the family of Sapindaceae.

Oleanane-type glycosides from the roots of Weigela florida "rumba" and evaluation of their antibody recognition.

Three triterpene glycosides were isolated from the roots of Weigela florida "rumba" (Bunge) A. DC.: two previously undescribed 3-O-ß-d-xylopyranosyl-(1→2)-[ß-d-xylopyranosyl-(1→4)]-ß-d-xylopyranosyl-(1→4)-ß-d-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-l-arabinopyranosyloleanolic acid (1) and 3-O-ß-d-xylopyranosyl-(1→2)-[ß-d-glucopyranosyl-(1→4)]-ß-d-xylopyranosyl-(1→4)-ß-d-xylopyranosyl-(1→3)-α-l-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyloleanolic acid (2), and one isolated for the first time from a natural source 3-O-ß-d-xylopyranosyl-(1→3)-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranosyloleanolic acid (3). Their structures were elucidated mainly by 2D NMR spectroscopic analysis (COSY, TOCSY, NOESY, HSQC, HMBC) and mass spectrometry. Compounds 2 and 3 were further evaluated as antigens in enzyme-linked immunosorbent assay (ELISA) to recognize IgM antibodies in multiple sclerosis (MS) patients' sera.

Triterpene saponins from Billia rosea.

Five previously undescribed triterpene saponins, billiosides A-E, and a known analogue, were isolated from the seeds of Billia rosea (Planch. & Linden) C. Ulloa & P. Jørg. Their structures were elucidated on the basis of extensive 1D and 2D NMR experiments (1H, 13C, DEPT, COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC) and mass spectrometry as (3ß,21ß,22α)-3-[(2-O-ß-D-glucopyranosyl-O-[α-L-arabinopyranosyl-(1 â†’ 4)]-ß-D-glucopyranosyl)oxy]-21-[((2E,6S)-2,6-dimethyl-6-hydroxyocta-2,7-dienoyl)oxy]-22-(acetyloxy)-24-hydroxyolean-12-en-28-oic acid, (3ß,21ß,22α)-3-[(2-O-ß-D-galactopyranosyl-ß-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-α-L-arabinopyranosyl-(1 â†’ 4)-ß-D-glucopyranoside, (3ß,21ß,22α)-3-[(2-O-ß-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 â†’ 4)]-ß-D-xylopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-ß-D-glucopyranoside, (3ß,21ß,22α)-3-[(2-O-ß-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 â†’ 4)]-ß-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-ß-D-glucopyranoside, (3ß,21ß,22α)-3-[(2-O-ß-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 â†’ 4)]-ß-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-ß-D-glucopyranosyl-(1 â†’ 6)-ß-D-glucopyranoside, and dipteroside A. Billiosides B and C exhibited moderate effects when tested as hepatic glucose-6-phosphatase inhibitors and as glucose intestinal absorption inhibitors, using in situ rat intestinal segments.

Oleanane-type glycosides from Pittosporum tenuifolium "variegatum" and P. tenuifolium "gold star".

The phytochemical study of two cultivars of Pittosporum tenuifolium Banks & Sol. ex Gaertn, "variegatum" and "gold star", led to the isolation of eight oleanane-type glycosides: seven previously undescribed and a known one. Their aglycons are oxygenated oleanane derivatives as barringtogenol C, camelliagenin A, hederagenin, and 22α-hydroxyoleanolic acid. Their structures were established by 2D NMR spectroscopic techniques and mass spectrometry as 3-O-ß-D-galactopyranosyl-(1 â†’ 2)-[α-L-arabinopyranosyl-(1 â†’ 3)]-ß-D-glucuronopyranosyl-21-O-angeloyl-22-O-acetylbarringtogenol C, 3-O-ß-D-galactopyranosyl-(1 â†’ 2)-[α-L-arabinopyranosyl-(1 â†’ 3)]-ß-D-glucuronopyranosyl-21,22-di-O-angeloylbarringtogenol C, 3-O-ß-D-galactopyranosyl-(1 â†’ 2)-[α-L-arabinopyranosyl-(1 â†’ 3)]-ß-D-glucuronopyranosyl-22-O-angeloylcamelliagenin A, 3-O-ß-D-glucopyranosyl-(1 â†’ 2)-[ß-D-glucopyranosyl-(1 â†’ 6)]-ß-D-glucopyranosyl-22-O-[(6-O-acetyl)-ß-D-glucopyranosyl]camelliagenin A, 3-O-ß-D-galactopyranosyl-(1 â†’ 2)-[α-L-arabinofuranosyl-(1 â†’ 4)]-ß-D-glucuronopyranosylhederagenin 28-O-ß-D-glucopyranosyl ester, 3-O-α-L-arabinofuranosyl-(1 â†’ 4)-ß-D-glucuronopyranosylhederagenin 28-O-ß-D-glucopyranosyl ester, 3-O-ß-D-galactopyranosyl-(1 â†’ 2)-[α-L-arabinofuranosyl-(1 â†’ 4)]-ß-D-glucuronopyranosyl-22α-hydroxyoleanolic acid 28-O-ß-D-glucopyranosyl ester, and the known ilexoside XLIX. These results represent a significative contribution to the chemotaxonomy of the genus Pittosporum, highlighting hederagenin-type saponins as chemotaxonomic markers of P. tenuifolium cultivars.

Triterpenoid saponins from the roots of Spergularia marginata.

Phytochemical investigations of the roots of Spergularia marginata had led to the isolation of four previously undescribed triterpenoid saponins, a known one and one spinasterol glycoside. Their structures were established by extensive NMR and mass spectroscopic techniques as 3-O-ß-D-glucuronopyranosyl echinocystic acid 28-O-α-L-arabinopyranosyl-(1 â†’ 2)-α-L-rhamnopyranosyl-(1 â†’ 3)-ß-D-xylopyranosyl-(1 â†’ 4)-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L- arabinopyranosyl ester, 3-O-ß-D-glucopyranosyl-(1 â†’ 3)-ß-D-glucuronopyranosyl echinocystic acid 28-O-α-L-arabinopyranosyl-(1 â†’ 2)-α-L-rhamnopyranosyl-(1 â†’ 3)-ß-D-xylopyranosyl-(1 â†’ 4)-α-L-rhamnopyranosyl-(1 â†’ 2)- α-L-arabinopyranosyl ester, 3-O-ß-D-glucopyranosyl-(1 â†’ 4)-3-O-sulfate-ß-D-glucuronopyranosyl echinocystic acid 28-O-α-L-arabinopyranosyl-(1 â†’ 2)-α-L-rhamnopyranosyl-(1 â†’ 3)-ß-D-xylopyranosyl-(1 â†’ 4)-α-L-rhamnopyranosyl-(1 â†’ 2)-α-L-arabinopyranosyl ester, and 3-O-ß-D-glucopyranosyl-(1 â†’ 4)-ß-D-glucuronopyranosyl 21-O-acetyl acacic acid. Their cytotoxicity was evaluated against two human cancer cell lines SW480 and MCF-7. The most active compound showed a cytotoxicity with IC50 14.2 ± 0.8 µM (SW480), and 18.7 ± 0.8 µM (MCF-7), respectively.

New pregnane and phenolic glycosides from Solenostemma argel.

From the aerial parts, pericarps and roots of Solenostemma argel, three new pregnane glycosides (1-3) with two known ones and a new phenolic glycoside (4) have been isolated. Their structures were established by extensive 1D - and 2D NMR and mass spectroscopic analysis. The cytotoxicity of all compounds was evaluated against two human tumor cell lines (SW 480, MCF-7), but none of them was active in the concentration range 0.9-59.0µM. Compounds 2 and the known argeloside F at non toxic concentrations for the PBMCs (27.3µM and 27.6µM, respectively) significantly decreased the Il-1ß production by LPS-stimulated PBMCs. All isolated compounds showed a significant antioxidant potential with ORAC values in the concentration range 3481-9617µmoleq. Trolox/100g.