Verbascoside is a polyphenol glycoside in which the phenylpropanoid caffeic acid and the phenylethanoid hydroxytyrosol form an ester and an ether bond respectively, to the rhamnose part of a disaccharide, namely β-(3′,4′-dihydroxyphenyl)ethyl-O-α-L-rhamnopyranosyl(1→3)-β-D-(4-O-caffeoyl)-glucopyranoside.
Occurrences
Natural occurrences
Verbascoside can be found in species in all the families of the order
Lamiales (syn. Scrophulariales).
Only two examples are known from outside the order,
in the clade
Asterids.
- in the Lamiales
In the family
Lamiaceae, it can be found in the medicinal plants in the genus
Phlomis,
in the
Scrophulariaceae, in
Verbascum phlomoides,
Verbascum mallophorum,
or, in the family
Buddlejaceae, in
Buddleja globosa or
Buddleja cordata,
in the family
Bignoniaceae, in
Pithecoctenium sp and
Tynanthus panurensis, in the family
Orobanchaceae, in
Cistanche sp and
Orobanche rapum-genistae,
in the
Plantaginaceae, in
Plantago lanceolata,
in
Verbenaceae, in
Verbena officinalis (common vervain),
Aloysia citrodora (lemon verbena) and
Lantana camara,
in the
Oleaceae, in
Olea europaea (
olive),
in the
Lentibulariaceae, in the carnivorous plant
Pinguicula lusitanica,
[ and, in the Byblidaceae, in Byblis liniflora.][
]
Derivatives
Verbascoside derivatives can be found in the Verbascum undulatum and notably in Verbascum sp.
In in vitro cultures
It can also be produced in plant cell cultures of Leucosceptrum sp (Lamiaceae) and Syringa sp (Oleaceae). It can also be produced in cultures of Paulownia tomentosa (empress tree, Paulowniaceae).
Biological activity
Verbascoside has an antimicrobial activity,[ notably against Staphylococcus aureus.][ It can also have anti-inflammatory properties.][
]
Although some in vitro genotoxicity of verbascoside has been reported on human with an involvement of PARP-1 and p53 proteins, subsequent in vivo tests reported no genotoxicity for high dosage oral administration. It is a protein kinase C inhibitor.[
]
See also