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New Laboratory Guidance Document Details Appropriate Methods of Analysis to Detect Synthetic Antimicrobial Compounds Sold as Grapefruit Seed Extract

AUSTIN, Texas (May 31, 2017) — The nonprofit ABC-AHP-NCNPR Botanical Adulterants Program announces the release of a Laboratory Guidance Document (LGD) on grapefruit (Citrus paradisi) seed extract (GFSE).

The new LGD is the third publication from the program dealing with the adulteration of GFSE. In 2012, the program published a review of scientific papers on the adulteration of GFSE in the American Botanical Council’s (ABC’s) peer-reviewed journal HerbalGram; in March 2017, the program published a Botanical Adulterants Bulletin that reviews all of the available evidence documenting concerns about and charges of adulteration of GFSE with synthetic antimicrobial compounds in products labeled to contain GFSE.

The new LGD is the first-ever detailed review of currently available laboratory analytical methods to identify synthetic antimicrobial compounds in products labeled to contain GFSE. GFSEs, which have no known history of use in traditional herbal medicine, are marketed as dietary supplements with antimicrobial activity and as a natural preservative for personal care and cosmetic products.

These analyses employed analytical techniques such as high-performance liquid chromatography (HPLC) with ultraviolet (HPLC-UV) or mass spectrometric (HPLC-MS) detection, thin-layer chromatography (TLC), gas chromatography-mass spectrometry (GC-MS), or nuclear magnetic resonance (NMR) spectrometry.

As with the two previous publications on the sale of synthetic microbicides as GFSE for the program, the LGD was written by John Cardellina, PhD, chief technical consultant and associate editor of the Botanical Adulterants Program. It has been peer-reviewed by the ABC-AHP-NCNPR Botanical Adulterants Program partners and, additionally, by five experts from both independent contract analytical laboratories and the herb and dietary supplement industry.

The program’s LGDs are intended for quality control personnel and lab technicians in the herbal medicine, botanical ingredient, dietary supplement, and food sectors of industry to help them choose the most appropriate techniques and methods for their specific analytical needs. They provide reliable, expert guidance on suitable methods to comply with the mandate to establish identity as an integral part of the testing requirements (identity, purity, strength, and composition) outlined in the US Food and Drug Administration’s (FDA’s) current Good Manufacturing Practices (cGMPs) for dietary supplements and/or conventional foods, as well as government-mandated cGMPs in other countries.

ABC Chief Science Officer Stefan Gafner, PhD, commented: “The changing nature of the antimicrobial compounds used to adulterate various batches of GFSE complicates the selection of an appropriate analytical method. A non-targeted approach, which means the use of a method where the compounds to be analyzed are not known, is required for the detection of these adulterants. Due to their ability to identify the presence of synthetic microbicides at low concentrations, GC-MS and HPLC-MS are particularly well-suited to meet the challenge.” 

“As we have noted previously, adulteration of grapefruit seed extract with synthetic industrial disinfectant chemicals is a particularly egregious practice,” said ABC Founder and Executive Director Mark Blumenthal, who is also the director of the Botanical Adulterants Program. “We believe that this should be the subject of appropriate regulatory action by the FDA.”

The GFSE LGD is the 31st peer-reviewed publication of the Botanical Adulterants Program and the fourth publication in the series of LGDs. All publications in the program are freely accessible to American Botanical Council (ABC) members, registered users of the ABC website, and all members of the public after registration on the ABC website.