1,721,004 research outputs found
The flavonoids and oil composition of parsley [Petroselinum crispum (Mill) Nyman] fruits
No full textThe chemical composition of the volatile, fixed oil and flavonoid fraction extracted from the fruits of parsley was investigated in two cultivar and a local ecotype of the species. Nine compounds were detected in the flavonoid fraction, being glycosyl and glycosyl malonate derivatives of apigenin and chrysoeriol the most abundant. Among these, apigenin 7-O-[apiofuranosyl(1→2)-β-glucopyranoside] (apiin) counted up to 6.97 mg·g−1 on average, while the compounds apigenin 7-O-[apiofuranosyl(1→2)-(6”-O-malonyl-β-glucopyranoside)] and chrysoeriol 7-O-[apiofuranosyl(1→2)-(6”-O-malonyl-β-glucopyranoside)], accounting for 15.01 mg·g−1 and 6.52 mg·g−1, respectively, were detected for the first time in the fruits of the species. Furthermore, the complete identification of the latter compound, performed by NMR techniques, was reported for the first time. The local ecotype contains higher amounts of six out of nine flavonoids detected, this result supporting the interest for its possible valorisation. Additionally, sixteen compounds were detected in the volatile fraction, being the alkenylbenzenes apiole, myristicin and 1-allyl-2,3,4,5-tetramethoxybenzene the most abundants, accounting respectively for 45.63 %, 35.89 % and 3.97 %, on average. In the fixed oil, petroselinic (60.92 %) and linoleic acid (10.30 %) were the main fatty acids, and apiole (11.95 %) the main alkenilbenzene detected. This study, aimed at the complete identification and quantitation of different classes of metabolites, representes to date the most exhaustive report on the evaluation of bioactive compounds in parsley fruits, a particular food resource endowed with promising nourishing features
Triterpene saponins from the roots of Medicago hybrida
Full text linkFourteen triterpene saponins (1−14) have been isolated from the roots of Medicago hybrida and their structures elucidated by FAB-MS and NMR analysis. Two of them are new compounds and were identified as hederagenin 3-O-[α-l-rhamnopyranosyl(1→2)-β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-28-O-β-D-glucopyranoside (7) and oleanolic acid 3-O-[β-D-galactopyranosyl(1→2)-β-D-glucuronopyranosyl]-28-O-[α-l-rhamnopyranosyl(1→4)-β-D-glucopyranoside] (14). Seven saponins being mono- and bidesmosides of hederagenin (1, 5, 6, 9), one bidesmoside of bayogenin (2), and two bidesmosides of 2β,3β-dihydroxyolean-12-en-23-al-28-oic acid (11) and oleanolic acid (13) are known compounds but not previously reported as saponin constituents of Medicago, whereas five other saponins, being mono- and bidesmosides of medicagenic acid (3, 4, 8, 10, 12), and one monodesmoside of hederagenin (8) have been previously isolated from other Medicago species. The presence of 2β,3β-dihydroxyolean-12-en-23-al-28-oic acid might represent an interesting intermediate in the biosynthesis of these substances.
Keywords: Medicago hybrida L.; triterpene saponins; chemical structure; FAB-MS; NM
Anti-nutrient components and metabolites with health implications in seeds of 10 common bean (Phaseolus vulgaris L. and Phaseolus lunatus L.) landraces cultivated in southern Italy
No full textCommon beans (Phaseolus vulgaris L.) provide an inexpensive food rich in macronutrients such as protein and starch, important micronutrients such as iron, and also a number of other stored bioactive compounds (phytates, polyphenols, tannins, raffinosaccharides, lectins, protease and α-amylase inhibitors, saponins, etc.) endowed with positive health implications through their antioxidant, anti-tumour or phyto-oestrogenic activity. They also produce negative dietary effects such as interference with micronutrient absorption, protein digestibility or glucose metabolism, or even direct toxic effects (lectins). Analysis of the levels of these compounds in seeds of local and underexploited common bean varieties and landraces may reveal traits of interest for promoting nutrition and preserving health, and in addition allow breeders to use them in genetic improvement programmes to modify the levels of specific compounds in new common bean varieties. In the present work, 10 bean populations belonging to 7 highly appreciated southern Italian landraces were analysed. The seeds of one of them, “Poverello di Rotonda AF”, was found to accumulate remarkable levels of 4 health-promoting components such as quercetin (24.2 μg/g), genistein (21.6 μg/g), soysapogenin B (433 μg/g) and oleanolic acid (11.9 μg/g), while “Tabacchino” contained very high amounts of iron (131 μg/g) and three health-promoting components: kaempferol (61.0 μg/g), oleanolic acid (12.3 μg/g) and condensed tannins (2.36 mg/g). A level of variation high enough to be exploited for breeding purposes was found for 7 out of 15 biochemical parameters studied
A trypsin inhibitor cDNA from a novel source, snail medic (Medicago scutellata L.): cloning and functional expression in response to wounding, herbivore, jasmonic and salicylic acid
No full textUnraveling the response of plant cells to cytotoxic saponins: role of metallothionein and nitric oxide
Full text linkA wide range of pharmacological
properties are ascribed to natural
saponins, in addition to their biological
activities against herbivores, plant soilborne
pathogens and pests. As for animal
cells, the cytotoxicity and the chemopreventive
role of saponins are mediated by
a complex network of signal transduction
pathways which include reactive oxygen
species (ROS) and nitric oxide (NO).
The involvement of other relevant components
of the saponin-related signaling
routes, such as the Tumor Necrosis
Factor (TNF)α, the interleukin (IL)-6
and the Nuclear Transcription FactorκB
(NFκB), has been highlighted in animal
cells. By contrast, information concerning
the response of plant cells to saponins
and the related signal transduction pathways
is almost missing. To date, there are
only a few common features which link
plant and animal cells in their response
to saponins, such as the early burst in
ROS and NO production and the induction
of metallothioneins (MTs), small
cysteine-rich, metal-binding proteins.
This aspect is discussed in the present
paper in view of the recent hypothesis
that MTs and NO are part of a novel signal
transduction pathway participating
in the cell response to oxidative stress
Triterpenoid Glycosides from Leaves of Medicago arborea L.
Full text linkEighteen triterpene saponins (1−18) from Medicago arborea leaves have been isolated and their structures elucidated by spectroscopic, spectrometric (1D and 2D NMR, FAB-MS, ESI-MS/MS), and chemical methods. They have been identified as glycosides of medicagenic, zanhic, and 2β-hydroxyoleanolic acids, soyasapogenol B, bayogenin, and 2β,3β-dihydroxyolean-12-en-23-al-28-oic acid. Twelve of them, identified as 3-O-β-D-glucopyranosyl-28-O-[α-l-arabinopyranosyl(1→3)-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside] zanhic acid (3), 3-O-β-D-glucopyranosyl-28-O-{β-d-xylopyranosyl(1→4)-[α-l-arabinopyranosyl-(1→3)]-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside} zanhic acid (4), 3-O-[α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranosyl(1→2)-β-d-glucopyranosyl]-2β-hydroxyoleanolic acid (5), 3-O-β-D-glucuronopyranosyl-28-O-[α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside]medicagenic acid (6), 3-O-β-D-glucuronopyranosyl-28-O-[β-d-xylopyranosyl(1→4)-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside]bayogenin (9), 3-O-β-D-glucuronopyranosyl-28-O-[β-D-xylopyranosyl(1→4)-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside]-2β,3β-dihydroxyolean-12-en-23-al-28-oic acid (10), 3-O-β-D-glucuronopyranosyl-28-O-{β-D-xylopyranosyl(1→4)-[β-D-apiofuranosyl(1→3)]-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside}zanhic acid (12), 3-O-β-D-glucuronopyranosyl-28-O-{β-d-xylopyranosyl(1→4)-[α-l-arabinopyranoside(1→3)]-α-l-rhamnopyrano-syl(1→2)-α-l-arabinopyranoside}zanhic acid (13), 3-O-β-D-glucuronopyranosyl-28-O-[β-D-xylopyrano-syl(1→4)-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside]zanhic acid (14), 3-O-[α-l-arabinopyranosyl-(1→2)-β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-28-O-{β-D-xylopyranosyl(1→4)-[β-D-apiofurano-syl(1→3)]-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyranoside}zanhic acid (16), 3-O-[β-D-glucopyrano-syl(1→2)-β-D-glucopyranosyl]-28-O-{β-d-xylopyranosyl(1→4)-[α-l-arabinopyranosyl(1→3)]-α-l-rhamno-pyranosyl (1→2)-α-l-arabinopyranoside}zanhic acid (17), and 3-O-β-D-glucuronopyranosyl-28-O-{β-D-xylopyranosyl(1→4)-[β-D-apiofuranosyl(1→3)]-α-l-rhamnopyranosyl(1→2)-α-l-arabinopyrano-side}medicagenic acid (18), are reported as new natural compounds. The presence of the aldehydic group on the sapogenin moiety of saponin 10 is discussed in the framework of a possible elucidation of the biosynthesis of these metabolites.
Keywords: Medicago arborea L.; saponins; chemical structure; triterpene glycosides; FAB-MS; ESI-MS/MS; NM
Enhanced triterpene saponin biosynthesis and root nodulation in transgenic barrel medic (Medicago truncatula Gaertn) expressing a novel b-amyrin synthase gene
Full text linkTriterpene saponins are a group of bioactive compounds abundant in the genus Medicago, and have been studied extensively for their biological and pharmacological properties. In this article, we evaluated the effects of the ectopic expression of AsOXA1 cDNA from Aster sedifolius on the production of triterpene saponins in barrel medic (Medicago truncatula Gaertn.). AsOXA1 cDNA encodes beta-amyrin synthase, a key enzyme involved in triterpene saponin biosynthesis. One of the four transgenic lines expressing AsOXA1 accumulated significantly larger amounts of some triterpenic compounds in leaf and root than did control plants. In particular, the leaf exhibited significantly higher levels of bayogenin, medicagenic acid and zanhic acid. The amounts of medicagenic acid and zanhic acid, which represent the core of the M. truncatula leaf saponins, were 1.7 and 2.1 times higher, respectively, than the amounts extracted from the control line. In root, the production of bayogenin, hederagenin, soyasapogenol E and 2beta-hydroxyoleanolic acid was increased significantly. The increase in the total amounts of triterpenic compounds observed in the leaves of transgenic lines correlated with the AsOXA1 expression level. Interestingly, the plants expressing AsOXA1 showed, under different growth conditions, improved nodulation when compared with the control line. Nodulation enhancement was also accompanied by a significant change in the soyasapogenol B content. Our results indicate that the ectopic expression of AsOXA1 in barrel medic leads to a greater accumulation of triterpene saponins and enhanced root nodulation
- …
