New Phenolics from Baccharis Leaf Exudate

1989 ◽  
Vol 44 (9-10) ◽  
pp. 727-730 ◽  
Author(s):  
E. Wollenweber ◽  
F. J. Arriaga-Giner ◽  
A. Rumbero ◽  
W. Greenaway
Keyword(s):  
Flavonoid Aglycones ◽  
Leaf Exudate

Several lipophilic phenolics were found in leaf resins of Baccharis species, reported earlier to produce terpenoids and flavonoid aglycones. They were identified by NMR and GC/MS studies, respectively. The structure of 2′,4′β-trihydroxy-6′-methoxychalcone from B. salicifolia was confirmed by synthesis. Phenylethyl caffeate and benzyl caffeate were found in B. sarothroides.

Flavonoid aglycones and triterpenoids from the leaf exudate of Lantana camara and Lantana montevidensis

1997 ◽  
Vol 25 (3) ◽  
pp. 269-270 ◽  
Author(s):  
Eckhard Wollenweber ◽  
Marion Dörr ◽  
R. Muniappan ◽  
Karsten Siems
Keyword(s):  
Lantana Camara ◽  
Flavonoid Aglycones ◽  
Leaf Exudate

A Novel Caffeic Acid Derivative and Other Constituents of Populus Bud Excretion and Propolis (Bee-Glue)

1987 ◽  
Vol 42 (9-10) ◽  
pp. 1030-1034 ◽  
Author(s):  
Eckhard Wollenweber ◽  
Yoshinori Asakawa ◽  
Detlef Schillo ◽  
Ulrich Lehmann ◽  
Heidrun Weigel
Keyword(s):  
Natural Product ◽  
Caffeic Acid ◽  
Acid Derivative ◽  
Sonoran Desert ◽  
Populus Nigra ◽  
Flavonoid Aglycones ◽  
Desert Shrub ◽  
Leaf Exudate ◽  
Caffeic Acid Derivative

Abstract The bud exudates of Populus nigra, P. trichocarpa, and P. grandidentata × tremuloides were analyzed for the presence of phenolics and flavonoids. A novel natural product, caffeic acid y.y-dimethylallyl ester, was identified from P. nigra, along with further phenolics such as ρ-hydroxy-acetophenone, dimethyl caffeic acid, cinnamoyl cinnamata and vanillin. The flavonoid aglycones correspond to those reported earlier. Propolis samples from the Sonoran Desert were shown to exhibit the flavonoid pattern that is typical for poplar bud exudates, thus confirming this material as the major source for bee-glue. Only a single flavonoid might originate from the leaf exudate of a desert shrub.

Terpenoids and Phenylethyl Esters from the Exudate of the Australian Plant Ozothamnus ledifolius (Asteraceae)

1998 ◽  
Vol 53 (3-4) ◽  
pp. 286-288 ◽  
Author(s):  
Fco. Javier Arriaga-Giner ◽  
Angel Rumbero ◽  
Eckhard Wollenweber
Keyword(s):  
Pentacyclic Triterpene ◽  
Flavonoid Aglycones ◽  
Triterpene Acids ◽  
Australian Plant ◽  
Leaf Exudate

Abstract The leaf exudate of Ozothamnus ledifolius, previously reported to contain a series of flavonoid aglycones, mostly consists of a mixture of terpenoids. From this resinous material we now identified four sesquiterpenes, a diterpenediol and two pentacyclic triterpene acids. In the phenolic portion we found three phenylethyl esters.

Flavonoid Aglycones in the Leaf Exudate of the Genus Leucocyclus (Compositae)

1989 ◽  
Vol 44 (3-4) ◽  
pp. 323-324 ◽  
Author(s):  
Karin M. Valant-Vetschera ◽  
Eckhard Wollenweber
Keyword(s):  
Original Material ◽  
Monotypic Genus ◽  
Related Genus ◽  
Flavonoid Aglycones ◽  
Taxonomic Implications ◽  
Leaf Exudate

Abstract The monotypic genus Leucocyclus, consisting of only two subspecies, was investigated for its exudate flavonoids. Major flavonoid aglycones were polymethoxyderivatives of 6-hydroxyflavones and, to a lesser extent, of 6-hydroxyflavonols. The two subspecies differed in their accumula­tion trends, but populational variation reduced the significance of taxonomic implications. Cultivated material corre­sponded largely to the original material collected from nature. The accumulation trends of Leucocyclus coincide with those of the closely related genus Achillea.

Flavonoid aglycones and flavonol glycosides in the lipophilic leaf exudate of Nothofagus antarctica

1997 ◽  
Vol 44 (7) ◽  
pp. 1399-1400 ◽  
Author(s):  
Eckhard Wollenweber ◽  
Andreas Stüber ◽  
Ludwig Kraut
Keyword(s):  
Flavonol Glycosides ◽  
Flavonoid Aglycones ◽  
Nothofagus Antarctica ◽  
Leaf Exudate

scholarly journals Bioconversion of Flavonoid Glycosides from Hippophae rhamnoides Leaves into Flavonoid Aglycones by Eurotium amstelodami

2019 ◽  
Vol 7 (5) ◽  
pp. 122 ◽  
Author(s):  
Qiuya Gu ◽  
Guoliang Duan ◽  
Xiaobin Yu
Keyword(s):  
Antioxidative Activity ◽  
Hippophae Rhamnoides ◽  
Flavonoid Glycosides ◽  
Total Phenolic ◽  
Total Phenolic Compounds ◽  
Flavonoid Aglycones ◽  
Hippophaë Rhamnoides ◽  
Tea Industry ◽  
Functional Factors ◽  
Flowering Process

The flowering process has been reported to play crucial roles in improving the flavor and efficacy of fermented tea. Hippophae rhamnoides leaves containing many beneficial ingredients are a suitable plant source for tea processing. In this study, we isolated a β-glucosidase-producing fungus Eurotium amstelodami BSX001 from the fermented tea and used Hippophae rhamnoides leaves (HRL) as a substrate to explore the detailed process of bioconversion of some important functional factors. The results show that the contents of total phenolic compounds and flavonoids increased significantly after seven days, especially flavonoid aglycones (e.g., quercetin, kaempferol, and isorhamnetin). Such compounds greatly enhance the antioxidative activity of fermented products. Metabolic analysis of the standard compounds (rutin, quercetin-3-glucoside, kaempferol-3-glucoside, quercetin, isorhamnetin-3-glucoside, isorhamnetin, and kaempferol) further confirmed the effective biotransformation by E. amstelodami. Mechanisms of the bioconversion could be involved in deglycosylation, dihydroxylation, and O-methylation. Our findings expand the understanding of tea fermentation process and provide further guidance for the fermented tea industry.

Flavonoid aglycones from the leaf surfaces of someLabiatae species

1990 ◽  
Vol 173 (3-4) ◽  
pp. 109-118 ◽  
Author(s):  
F. A. Tom�s-Barber�n ◽  
E. Wollenweber
Keyword(s):  
Flavonoid Aglycones ◽  
Leaf Surfaces

Acylated flavonoid aglycones from Gnaphalium robustum

1990 ◽  
Vol 29 (4) ◽  
pp. 1342-1343 ◽  
Author(s):  
Alejandro Urzua ◽  
Pedro Cuadra
Keyword(s):  
Flavonoid Aglycones
Sign in / Sign up

Export Citation Format

Share Document