- New faster analytical technique could
help address quality control issues
- Consumers of Ginkgo biloba herbal products,
offered in alternative medicine circles as a remedy for just about everything
from dementia to impotence, may not be getting their money's worth, according
to a new study by scientists at the University of Idaho. Using a new analytical
chemistry technique they developed specifically to examine Ginkgo samples,
the researchers found variations of up to tenfold in the Ginkgo products
- "Consumers seldom can be sure exactly
what they are buying," says chemistry professor Chen Wai, Ph.D., lead
researcher for the study, which will appear in the July 15 print issue
of the peer-reviewed science journal Analytical Chemistry, published by
the American Chemical Society, the world's largest scientific society.
The report initially was published on the journal's Web site on May 29.
- "The large variation of active ingredients
found in Ginkgo biloba products could be a problem for the consumers,"
the researchers write in the journal article.
- Ginkgo products are based on herbal extracts
from the leaves of the Ginkgo biloba tree, also known as the maidenhair
tree, which first appeared on Earth during the time of the dinosaurs about
200 million years ago. Widely marketed as a way of improving mental alertness
and slowing the development of Alzheimer's disease, Ginkgo supplements
are among the top selling herbal products in both Europe and the U.S. and
have long been a staple of Chinese herbalists.
- Chemical substances known as ginkgolides
and bilobalide, found in the leaves of the tree, are believed to be the
most pharmacologically active compounds, say the researchers. However,
they point out, as is the case with many herbal products, the active ingredients
are usually present in only trace amounts along with large quantities of
other compounds. Determining the amount of ginkgolides and bilobalide in
Ginkgo products generally is a time-consuming and tedious process, which
has added to the difficulty of establishing efficient quality control programs
for the products, claim the researchers.
- "The lack of simple and reliable
separation and analytical processes for herbal products is probably a major
cause of the quality-related problems found in the herbal medicine market
today," according to the researchers.
- The process developed by Wai and colleague
Qingyong Lang could help solve that problem by reducing the time required
to separate the active ingredients from hours to just a few minutes. It
essentially involves boiling the leaves of the tree, or Ginkgo extract
products, to separate the ginkgolides and bilobalide and then using a common
analytical instrument called a gas chromatograph to measure the compounds.
- "Compared to other reported methods
for ginkgolide separation, this method can significantly reduce the operation
time," say the researchers. "The principle of this analytical
method may also be applied to other medicinal herbs," they add.
- A nonprofit organization with a membership
of nearly 159,000 chemists and Chemical engineers as its members, the American
Chemical Society publishes scientific journals and databases, convenes
major research conferences, and provides educational, science policy and
career programs in chemistry. Its main offices are in Washington, D.C.,
and Columbus, Ohio. <http://www.acs.orghttp://www.acs.org
- Note: This story has been adapted from
a news release issued by American Chemical Society for journalists and
other members of the public. If you wish to quote from any part of this
story, please credit American Chemical Society as the original source.
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