61 research outputs found
Tracer method (14C-labelling) for investigating the metabolic flux pattern in triterpenoid biosynthetic pathway in Calendula officinalis hairy roots after elicitation with jasmonic acid
Comparison of the profiles of non-glycosylated triterpenoids from leaves of plants of selected species of genus Dioscorea
Remarkable qualitative and quantitative differences in non-glycosylated triterpenoid profiles of twelve Dioscorea spp. leaves were demonstrated with the use of GC-MS/FID analysis. The total content of tetracyclic triterpenoids and their esters ranged from 397 μg/g of dry leaf weight in D. bulbifera to 762 μg/g d.w. in D. discolor and 777 μg/g d.w in D. alata. Three main phytosterols, i.e. campesterol (1), sitosterol (2) and stigmasterol (3) were found in extracts from all analyzed species in total amount ranging from 316 μg/g in D. bulbifera to 676 μg/g of dry leaf weight in D. hispida, with either sitosterol (2) or stigmasterol (3) as predominant in the profile. Extracts from D. hispida and D. purpurea leaves were distinguished from the others by particular high amount of campesterol (1). In the majority of the species, except for D. caucasica, other tetracyclic triterpenoids were found: cycloartanol (4), 24-methylenecycloartanol (5) and cycloeucalenol (6). Less common steroids, stigmastan-3-en-6β-ol (7) and ergosta-7,22-dien-3β-ol (8) were detected in D. japonica. The significant content (992 μg/g) of pentacyclic triterpenoids of ursane, oleanane, taraxastane and taraxerene (friedooleanane)-type carbon skeletons, i.e. α-amyrin (9), β-amyrin (10), taraxasterol (11) and taraxerol (12), respectively, was found in D. caucasica. The obtained results supplement the knowledge of biochemical diversity of Dioscorea genus
GC-MS analysis of steroids and triterpenoids occurring in leaves and tubers of Tamus edulis Lowe
Tamus edulis Lowe is an endemic perennial plant belonging to Dioscoreaceae family. The plant has long climbing
stems, ovate leaves, flowers in spikes, fleshy red berries and long tuberous roots. Young shoots and tuberous
roots of T. edulis were used traditionally for nourishment and as a herbal medicine. Leaves and roots analyzed in
the present study were collected in the northwest of Madeira island. The GC–MS analysis allowed to detect
several steroids in free forms in diethyl ether extracts; and diosgenin with its isomer, yamogenin, in hydrolyzates
from methanolic extracts.The obtained results reveal that Tamus edulis has some features common with other
Dioscorea species, e.g., the presence of steroidal saponins with diosgenin and yamogenin as aglycones, or the
phytosterol composition with predominating sitosterol. However, some other traits, like the relatively high
content of free steroids (more than 1 mg/g d.w.) and their profile rich in cholesterol derivatives, can distinguish
Tamus edulis from other Dioscorea species studied previously for their steroid and triterpenoid profile.info:eu-repo/semantics/publishedVersio
Insights into epicuticular wax composition of fruits and leaves of Saskatoon (Amelanchier alnifolia Nutt. cv. Smoky and Northline)
Metabolism of sterols and pentacyclic triterpenoids in grapevine Vitis vinifera leaves elicited with methyl jasmonate
Exploring free and glycosidic forms of triterpenoids in cuticular waxes and tissues of chokeberry and blackberry leaves
Metabolomic alterations in elicitor-treated grapevine Vitis vinifera leaves monitored by 1H NMR
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