Summary from nutraingredients.com:
Study finds widespread adulteration of grape seed extract
... the paper looked at 21 commercially available grape seed extract (GSE) supplements [purchased from a variety of outlets, including online]. GSE is a complex mix of proanthocyanidin monomers and oligomers and other chemicals, the authors noted...
Overall, the quality of commercially available GSE products was low. “Very few of the commercial GSE samples contained an overall content of PACs [proanthocyanidins] and catechins at a level comparable to authentic GSE, which raises a serious concern,” they wrote.
And adulteration was rampant. “Overall six of the commercial samples could be considered seriously adulterated, perhaps counterfeit, while another five samples contained considerably less PACs and catechins than the remaining commercial samples,” they wrote.
The six worst samples appeared to consist almost entirely of peanut skin extract. The adulteration issue notwithstanding, this could be a serious concern as peanuts are a very dangerous potential allergen, the authors wrote...
Abstract:
Chemical investigation of commercial grape seed derived products to assess quality and detect adulteration
Highlights
• 21 commercial grape seed extract containing products were analyzed using LC–MS.
• 15 of the 21 were quality challenged, including six samples which were adulterated with high levels of peanut skin extract.
• Non-chromatographic assays now often employed by industry were not able to differentiate adulterated GSE.
• A simple TLC method was developed to quickly detect adulteration of grape seed extract.
Abstract
Fundamental concerns in quality control arise due to increasing use of grape seed extract (GSE) and the complex chemical composition of GSE. Proanthocyanidin monomers and oligomers are the major bioactive compounds in GSE. Given no standardized criteria for quality, large variation exists in the composition of commercial GSE supplements. Using HPLC/UV/MS, 21 commercial GSE containing products were purchased and chemically profiled, major compounds quantitated, and compared against authenticated grape seed extract, peanut skin extract, and pine bark extract. The antioxidant capacity and total polyphenol content for each sample was also determined and compared using standard techniques. Nine products were adulterated, found to contain peanut skin extract. A wide degree of variability in chemical composition was detected in commercial products, demonstrating the need for development of quality control standards for GSE. A TLC method was developed to allow for rapid and inexpensive detection of adulteration in GSE by peanut skin.
Edited by blood, 02 December 2014 - 06:20 AM.
