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| Parthenolide in Feverfew |
Answered by: Conrad Richter
Question from: Hazel Mader
Posted on: May 28, 1998
I noticed while recently rereading the Prairie Medicinal Plants Conference - 1996, at which you spoke, that Richters had performed tests on a number of varieties of feverfew, with widely varying results. As recipient of Richters seed (through a friend) I am wondering if there is a way to determine which of these varieties she may have actually purchased, or whether all of the varieties mentioned in the study are from your inventory. My seed was purchased in 1996.
It is very important to me to determine exactly what I have, since we have had disappointing HPLC results, and I have spent considerable effort on propagation and cultivation.
We were, and are, selling is what is known as ‘wild feverfew’, originally from a U.K. line. None of the improved lines we reported on in 1996 have been released yet.
This line is the same one that is being used by feverfew growers in Ontario and is producing acceptable levels of parthenolide (0.6%).
It is important to know that genetics seems to have much less to do with the parthenolide level as cultural conditions and other environmental factors. In 1996 we showed that there are large genetic differences between lines. But a given line that produces 0.6% parthenolide one year can produce 0.1% the next year -- and there is little clear indication exactly what is causing this year-to-year variation.
Recently, the opinion of leading experts has been moving toward one where parthenolide has little to do with the medicinal effect of feverfew. There is a suggestion that feverfew may owe some of its medicinal effect to melatonin now known to be found in feverfew.
It is unfortunate that the Health Canada has chosen to use parthenolide as a measure of quality. Originally, when parthenolide was proposed, the literature seemed to suggest that parthenolide was the appropriate measure of bioactivity in feverfew. In order to apply for a Drug Identification Number (DIN) in Canada, Health Canada requires that you show that your product has 0.2% parthenolide. However, now, some experts are suggesting that parthenolide should only be used as an identifying marker, merely to to prove that your product is true feverfew, and not some other substituted material. But with evidence emerging that parthenolide may be irrelevant medicinally, it is possible that the Health Canada standard will cause some perfectly good feverfew product to be undervalued or wasted. In any case, it may be putting undue pressure on growers to produce high parthenolide product.
Also was wondering how your fact sheets and your seed certification programs are progressing.
We hope to announce something in these areas later this year. The tardy Grow Sheets are now progressing well: a database has been constructed and it is working well. When customers contact Richters for technical information, our support staff uses the database now.