Austin, TX—The ABC-AHP-NCNPR Botanical Adulterants Prevention Program (BAPP) announced the publication of a new Laboratory Guidance Document (LGD) on Grape Seed Extract (GSE). It is the 50th peer-reviewed publication from the program.
The latest ABC/HerbalGram herb market report for 2017 found that GSE was not among the 40 top-selling botanical dietary supplement ingredients in the US, in spite of the fact that, according to a press release, GSE has been shown in human clinical trials to improve parameters related to cardiovascular health in human clinical trials.
Grape seeds are a good source of proanthocyanidins (PACs), the release says, to which many of the commercially available bulk ingredients are standardized. However, they are not the only source of PACs, nor are they the cheapest, and combined with difficulties in unambiguously identifying the source material of PAC-rich extracts, the release says that it is easy for dishonest suppliers to adulterate grape seed extract.
The new LGD was written by Steve A. Kupina and Mark A. Kelm, Ph.D., directors of quality and technology and research and development, respectively, at botanical ingredient manufacturer Polyphenolics; Maria J. Monagas, Ph.D., scientific liaison for dietary supplements and herbal medicines at the US Pharmacopeial Convention; and Stefan Gafner, Ph.D., chief science officer of ABC and technical director of BAPP.
The LGD provides an evaluation of the usefulness of published analytical methods to detect GSE adulteration, and summarizes the main advantages and disadvantages of each method regarding its suitability for use in a quality control laboratory. It details the chemical composition of grape seed, potential confounding species, and known adulterants. It has been peer-reviewed by 25 international experts.
In the press release, Gafner explained: “There is a reason why BAPP’s most recent laboratory guidance documents on cranberry and grape seed extracts have dealt with PAC-rich ingredients. PAC-derived materials are most often difficult to authenticate, and many suppliers have been using inappropriate tests based on spectrophotometric methods as a means to document the authenticity. Many of the lessons learned from GSE adulteration may be applied to the verification of the identity of other ingredients that contain condensed tannins. As such, this laboratory guidance document may not only benefit those working on GSE, but also those whose duty it is to verify the identity of condensed tannin-containing plant materials, e.g., cinnamon bark, apple fruit, or pine bark extracts.”
Mark Blumenthal, founder and executive director of ABC and founder and director of BAPP, said, “This new milestone for BAPP speaks to the high output of the program, and shows our continued commitment to the high quality and reliability of our extensively-peer-reviewed publications. It reflects both the quality and quantity of our research and educational efforts to provide responsible members of the herb and dietary supplement industry worldwide with authoritative resources that can help them properly authenticate botanical raw materials, extracts, and essential oils—and detect those that may be adulterated.”
LGDs are freely accessible to all ABC members, registered users of the ABC website, and all members of the public, here.