Botanical Adulterants Bulletin Highlights the Presence of Synthetic Antimicrobial Compounds in ‘Grapefruit Seed Extract’

AUSTIN, Texas (March 23, 2017) — The American Botanical Council (ABC)- American Herbal Pharmacopoeia (AHP)- National Center for Natural Products Research (NCNPR) Botanical Adulterants Program (BAP) has published a new Botanical Adulterants Bulletin (BAB) on Adulteration of Grapefruit Seed Extract.

Grapefruit seed extract (GFSE) is marketed as a dietary supplement with antimicrobial activity and as a natural preservative for personal care and cosmetic products. The seed of grapefruit (Citrus paradisi) has no known history of use in traditional herbal medicine.

As early as 1991, the occurrence of undeclared synthetic antimicrobial compounds (i.e., triclosan and methylparaben) was reported in products marketed as GFSE. Thirteen published papers have provided evidence for adulteration of GFSE with these and other synthetic microbicides, such as benzalkonium chloride, benzethonium chloride, cetrimonium bromide, and propylparaben. However, none of these studies found chemical compounds that are characteristic of grapefruit seed in the adulterated products, which suggests that any antimicrobial effects of these products were due to the undeclared microbicides rather than authentic GFSE.

The GFSE bulletin contains information about the production and market importance of GFSE, known adulterants, and analytical approaches to detect adulterants. It was authored by John Cardellina, PhD, chief technical consultant and associate editor of BAP. The bulletin has been peer reviewed by 12 experts from contract analytical laboratories, nonprofit organizations, the US government, and the herb and dietary supplement industry.

The goal of the BABs is to provide accounts of ongoing issues related to botanical identity and adulteration and inform quality control personnel and lab technicians in the herbal medicine, dietary supplement, cosmetic, conventional food, and other industries in which botanical ingredients are used about adulteration problems that may be widespread and/or that may constitute safety problems.

This bulletin marks the second publication on GFSE as part of the BAP’s ongoing efforts to educate industry members and other stakeholders about the adulteration of GFSE. The first publication on GFSE adulteration appeared in ABC’s peer-reviewed journal HerbalGram, issue 94, in 2012.

“The adulteration of ‘grapefruit seed extract’ with undisclosed synthetic disinfectant chemicals is a particularly egregious practice,” noted Mark Blumenthal, founder and executive director of ABC and director of the BAP. “There has been no credible explanation as to why these synthetic compounds have been continually detected by independent laboratories over the past 25 years; the only logical conclusion is that they are being added intentionally. This appears to be adulteration, and, as such, it is fraud. This issue requires investigation by the US Food and Drug Administration and other appropriate agencies internationally.”

Dr. Cardellina commented: “Almost five years after publication of the review of the adulteration of GFSE in HerbalGram, analyses continue to show that some so-called GFSE products in the marketplace are adulterated with synthetic microbicides. A recent seminal paper from Dr. Ikhlas Khan’s research group at the NCNPR at the University of Mississippi provides a critical new tool to address this problem: an analytical method that can simultaneously identify and quantify both the natural constituents of grapefruit seed and also the suite of synthetic disinfectants found for more than 25 years in commercial GFSE products. This new method warranted the issuance of this bulletin.”

ABC Chief Science Officer Stefan Gafner added: “While there are authentic GFSE products available on the market with respect to their containing citrus-related compounds, the sale of synthetic antimicrobial chemicals labeled as GFSE is still ongoing. We hope that our continuing efforts to raise awareness of the issue will ultimately lead to a disappearance of these fraudulent products.”

The GFSE bulletin is the ninth publication in the series of BABs. As with all publications in the program, the bulletins are freely accessible on the program’s website.