Kauralexins and zealexins, members of a larger family of plant-defense compounds known as "terpenoid phytoalexins
," are also partly triggered by insect chewing--with Ostrinia nubilalis, the European corn borer, among species that find them distasteful.
Phenylalanine ammonia lyase enzyme catalyzes the first step in the phenylpropanoid metabolism, which is the conversion of L-phenylalanine to trans-cinnamic acid which leads to the synthesis of defense related compounds including lignins and phytoalexins
(Rookes and Cahill, 2003).
Another technique might be to externally challenge post-harvested plants, such as grapes, with UV radiation, which would lead to an increase in the levels of resveratrol, a phytoalexin
, in grapes.
With this concept in mind, the new term "paldoxin" was coined to designate potential PhytoALexin
In this study we used fluorescence polarization (FP) to investigate the estrogenic activity of isoflavones, coumestans, phytoalexins
, and mycoestrogens in competition binding assays with human ER[Alpha] and ER[Beta].
Resveratrol (3,5,4'-trihydroxy-trans-stilbene), a phytoalexin
produced naturally by several plants when under attack by pathogens such as bacteria or fungi, significantly extends the lifespan of the yeast Saccharomyces cerevisiae, Caenorhabditis elegans and the fruit fly Drosophila melanogaster.
Elicitor-induced association of isoflavone omethyltransferase with endomembranes prevents the formation and 7-omethylation of daidzein during isoflavonoid phytoalexin
Resveratrol (trans-3,5,4'-trihydroxystilbene) is a stilbenoid, a type of natural polyphenol and aromatic phytoalexin
found predominantly in grapes, berries (mulberries), and Japanese knotweed.
Concentration of the phytoalexin
resveratrol in wine.
Protective effect of resveratrol, a polyphenolic phytoalexin
on glycerol-induced acute renal failure in rat kidney.
elicitation in grape berries and their susceptibility to Rhizopus stolonifer.
This antimicrobial role of phenolics is based on indirect evidence, such as correlations between the timing of phytoalexin
accumulation in resistant and susceptible interactions and the potency of phenolics as antimicrobial agents in vitro.