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(Last modification: 17. October 2010)
Some introductory remarks
I am something asked: how many plants do contain the wonderful resveratrol, the miracle drug? It really is a bit strange, if one looks at various publications with respect to that question. Most say something like "a number of plants"; others rather think it is "wide-spread", others use the term "limited", and the few giving a number do not tell where they got them from. I guess the fact is that hardly any of the standard paper writers on the benefits of resveratrol ever bothered to really make a check on that. And I admit that this is not easy because one really has to go into the details on publications on natural products. This is pretty difficult because there are so many specialized Journal on these topics. So please don't ask me: I do not have a reliable answer either (but I may try to find out, if I ever get enough time for that). One of the reasons why I am hesitant to spend time on that: I think that it is too simple-minded to look only at resveratrol. It is only one example of a huge group of biosynthetically related compounds; many of the others certainly have interesting pharmacological properties. At least from a biological point of view, and even more importantly, considering the biosynthesis: One should at least extend the view to the general term "stilbenoids", a term encompassing a huge number of additional compounds that are most likely synthesized via the same key reaction as resveratrol. There are indeed people who collect all this information, and my recommendation is to look at these two publications: Gorham, 1995: this book reviews the information up to 1994, Shen et al. 2009: this review summarizes new naturally occurring stilbenoids described between January 1995 to end of 2008: the number is simply amazing; there are about 400 new discoveries! Efforts like that might appear boring to many "modern" scientists, but in the long run they are crucial for understanding the diversity of enzyme reactions, and their evolution. And even that is a bit narrow-minded if one considers the biosynthetic key reaction: the term stilbenoids only covers those compounds in which a substrate from the phenylpropanoid pathway is used. The same key reaction, however, is used by enzymes with other substrates, and there are already examples that these reactions are catalyzed by members of the same protein family, the type III PKS (polyketide synthases). A few well-documented examples are the biphenyl synthase from Sorbus aucuparia (more...), and the alkylresorcinol synthase from Sorghum bicolor (more...), and there are more candidates.
Talking about type III PKS: now it really gets interesting because we are talking about the large number of functions catalyzed by members of a large superfamily (more...): the reactions for resveratrol biosynthesis are just one example!
The purpose of the pages here is not to provide comprehensive overviews. They simply summarize information on some plants that I found interesting. Below is a list of the presently available pages; there are likely to be additions in the future.
Citations :
Natural stilbenes have been a hot research topic due to their intricate structures and diverse biological activities. Although their molecular backbone consists only of 1,2-diphenylethylene units, stilbenes show an enormous diversity with regard to the different units present, the degree of polymerisation, and the pattern of oligomer construction. From January 1995 to the end of 2008, more than 400 new naturally occurring stilbenes were isolated and identified, and this review focuses on their structural diversity, distribution, and bioactivity. File History:
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