The Bright and Dark Sides of Herbal Infusions: Assessment of Antioxidant Capacity and Determination of Tropane Alkaloids

Toxins (Basel). 2023 Mar 27;15(4):245. doi: 10.3390/toxins15040245.

Abstract

Herbal infusions are highly popular beverages consumed daily due to their health benefits and antioxidant properties. However, the presence of plant toxins, such as tropane alkaloids, constitutes a recent health concern for herbal infusions. This work presents an optimized and validated methodology based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction procedure followed by Ultra-High Performance Liquid Chromatography combined with Time-of-Flight Mass Spectrometry (UHPLC-ToF-MS) for the determination of tropane alkaloids (atropine, scopolamine, anisodamine, and homatropine) in herbal infusions, in accordance with criteria established by Commission Recommendation EU No. 2015/976. One of the seventeen samples was contaminated with atropine, exceeding the current European regulation regarding tropane alkaloids. In addition, this study evaluated the antioxidant capacity of common herbal infusions available on Portuguese markets, indicating the high antioxidant capacity of yerba mate (Ilex paraguariensis), lemon balm (Melissa officinalis), and peppermint (Mentha x piperita).

Keywords: QuEChERS; antioxidant capacity; herbal infusions; time-of-flight mass spectrometry; tropane alkaloids; ultra-high performance liquid chromatography; validation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids* / analysis
  • Antioxidants*
  • Atropine
  • Chromatography, High Pressure Liquid
  • Tandem Mass Spectrometry / methods
  • Tropanes / analysis

Substances

  • Antioxidants
  • Tropanes
  • Alkaloids
  • Atropine

Grants and funding

This work was financially supported by the research project ValICET (PRIMA/0001/2020)—Valorise Foods and Improve Competitiveness through Emerging Technologies applied to food by-products within the circular economy framework (Section 2 PRIMA project) funded in Portugal by the Foundation for Science and Technology (FCT). The work was supported by UIDB/00211/2020, with funding from FCT/MCTES through national funds. A.R.S.M. would like to thank the ValICET project for her fellowship (03/2022/BI). A. Sanches Silva is grateful to the Foundation for Science and Technology (FCT) for funding the ValICET project in Portugal (PRIMA/0001/2020).