Advantra Z Found to Contain Only P-Synephrine Isomer

Independent Research Confirms Patented Ingredient Lacks Isomer that has Potential to Raise Blood Pressure

Wayne, N.J., July 27, 2005 – Nutratech, Inc., a supplier of ingredients to the weight-loss and sports nutrition markets, announced today that its proprietary bitter orange-based ingredient, Advantra Z®, contains p-synephrine, a stable isomer of the synephrine alkaloid, but does not contain m‑synephrine, which has the potential for raising blood pressure in humans.

“We have had Advantra Z tested by independent laboratory Chromadex, which confirmed Advantra Z contains no m-synephrine,” said Bob Green, Nutratech president. Chromadex had previously been contracted by the National Institutes of Health, Office of Dietary Supplements, to determine a method of evaluating synephrine alkaloids.

The testing of Advantra Z was spurred by a technical report written by several doctors in the 2005 International Journal of Obesity, entitled, “Exactly which synephrine alkaloids does Citrus aurantium (bitter orange) contain?”

The report observed that bitter orange is comprised of a number of constituents – the most prominent being synephrine – and that there are six possible isomers of synephrine (para, meta, ortho; and for each a “d” or “l” form). Most bitter orange ingredients are believed to contain both m‑synephrine and p‑synephrine. The “m” form, called phenylephrine, is used in nasal decongestants, such as Neo-Synephrine, and to treat hypotension (low blood pressure) and is said to be a strong vasoconstrictor (causing a narrowing of the blood vessels) and, in turn, may raise blood pressure.

“Understanding which synephrine isomer is used in Advantra Z is important since bitter orange and the possibility that it raises blood pressure has been the topic of a variety of studies and media reports during the past year,” said Green.

In a letter to the editor appearing in the December, 2004, issue of the Mayo Clinic Proceedings, Nicole Bouchard, M.D., and Robert S. Hoffman, M.D., helped clarify the confusion surrounding m-synephrine and p-synephrine by explaining that while both compounds have the same chemical formula, in m-synephrine the hydroxyl group is located on the No. 3 carbon of the benzene ring, whereas in p‑synephrine the hydroxyl group is located on the No. 4 carbon.

“This small difference produces important changes in the stereochemistry that might alter the biological activity of these two compounds. Therefore they should not be used as equivalents,” Bouchard and Hoffman explained in their letter, which was in response to an August 2004 article that failed to distinguish between the “m” and “p” compounds.

“Because Advantra Z contains only the “p” form of synephrine, manufacturers of diet and fitness products can assure consumers that their products incorporate a holistic bitter orange extract that contains a more stable and safe form of synephrine,” said Green. He added that this added distinction between generic bitter orange and Advantra Z is why manufacturers should use “Contains patented Advantra Z” on the label and in their advertising.

Nutratech, Inc., provides innovative, proprietary and patented nutraceutical ingredients to the dietary supplement, weight management, sports nutrition, beverage and food industries. The company is headquartered in Wayne, N.J. For more information on Nutratech and Advantra Z, visit the company’s web site at

# # #

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.