(P03-005-23) Authentication and Safety of Commercial Guarana (Paullinia cupana L) Powdered Extracts

Objectives: The objective of this study is to assess safety and quality of a new guarana formulation and its comparison to existing commercial products.

Methods: Authentication of the new guarana formulation and comparable commercial products was based on caffeine and flavan-3-ols content determined by High Performance Liquid Chromatography (HPLC; Klein et al. 2012; Talanta, 88, 502-506), and gas chromatography for volatile fingerprint analysis (Inarejos-García et al. 2021 ACS Food Sci. Technol., 1, 4, 596–604), as well as carbon-13 site-specific natural isotopic fractionation-nuclear magnetic resonance (SNIF-NMR) according to Thomas et al. 2010 (J. Agric. Food Chem., 58, 11580–11585). Safety was determined in AMES test to assess mutagenicity and in vivo micronucleus test in mice for clastogenic effects at doses 114 mg/kg, 228 mg/kg or 456 mg/kg.

Results: Reference guarana seeds used as control showed in average (dry basis) 3.2±0.2% of caffeine, and 1.3±0.1% of flavan-3-ols by HPLC. All analyzed samples showed a caffeine levels between 1.5% and 12%, but commercial extracts contained higher concentration than the reported markers. When analyzed by gas chromatography, the reference material showed a significant content of terpenes, and other positive volatiles such as benzaldehyde or eugenol. For caffeine authentication, carbon-13 SNIF-NMR analyses showed that most of commercial guarana products contained significantly higher natural caffeine than the reference material, suggesting that the caffeine has been added to the product. In addition, one of the samples contained synthetic caffeine. Our new formulation of guarana has been assessed for safety and did not show any cytotoxicity (PCE/TE). Further, no increase in micronucleated polychromatic erythrocytes (MNPCEs) was observed, indicating that the new guarana formulation is not clastogenic. The Ames test showed no mutagenicity.

Conclusions: Caffeine and flavan-3-ols quantifications and their calculated ratio allowed to reveal the origin of the caffeine in the finished products, (whether derived from the plant or added). In addition to its natural caffeine content, the new formulated guarana was found to be non-mutagen and non-clastogenic at all doses. It can be concluded that our new formulated guarana is safe and of a high quality.

Funding Sources: Thanks to ADM® for funding this research work.