|
(Last modification:
19. Feb. 2008)
Biological roles of
CHS and STS products
CHS (Chalcone
synthase)
-
distribution: ubiquitous in
higher plants
-
functions of chalcone derivatives:
-
- flower colours (insect attractants)
-
- UV protection
-
- defense against pathogens (phytoalexins)
-
- interaction with microorganisms: nodule formation (Rhizobium)
-
- fertility (flavonols) (e.g. in
Petunia and Zea mays, but
apparently not Arabidopsis)
-
medicine:
there is a large body of literature showing that flavonoids
can be beneficial for human health
- protective antioxidant properties:
flavonoid pills
are very popular!
Return to
overview of type III polyketide synthases
STS (Stilbene synthase),
and its possibly most important example: resveratrol synthase
Some important points to remember:
-
Resveratrol and other stilbenes:
-
- rare in higher plants, in
particular in the most important crop plants
-
- the most noticeable exceptions are peanuts and grapes
-
- see
also Resveratrol in transgenic Plants
-
- occurring in widely unrelated plant families
-
- there is good evidence that the capacity for resveratrol (stilbene)
synthesis developed
several times independently in different plant families
-
Functions of stilbenes and their derivatives in plants:
-
- in wood: resistence against microbial degradation
-
- in other parts of plants:
-
- defense against pathogens (phytoalexins)
-
- stress response (e.g. high ozone concentrations)
-
In other organisms (most importantly in humans!):
The last few years have brought a steadily increasing number of publications
on the effects of resveratrol and its derivatives on human health. As it is
often the case, the complexity of the potential effects in humans makes it
difficult to estimate with some certainty whether the benefits are as high as
claimed. However, many readers are convinced, and the last years brought some new findings
that are indeed very exciting. A brief
overview on resveratrol, its
biosynthesis and possible functions
can be found
here. There is also
a list of selected
reviews/commentaries and
original publications on the importance of resveratrol in human medicine,
with the keyword 'anti-aging'.
October 2009: there is now a
much more detailed overview on the possible medical application of
resveratrol: more...
Go to Resveratrol: Overview and Biosynthesis, or
Selected References, or
Discussion of Anti-Aging,
or to some References on Resveratrol in
Transgenic Plants and other Organisms.
Go to
Overview on Type III Polyketide Synthases
or
Return to top |
