Phenolome of Asian Agrimony Tea (<i>Agrimonia asiatica</i> Juz., Rosaceae): LC-MS Profile, α-Glucosidase Inhibitory Potential and Stability

• Main Authors: Nina I. Kashchenko, Daniil N. Olennikov
• Format: Article
• Language: English
• Published: MDPI AG 2020-09-01
• Series: Foods
• Subjects: <i>Agrimonia asiatica</i>; Rosaceae; ellagitannins; agrimoniin; high-performance liquid chromatography; mass spectrometry
• Online Access: https://www.mdpi.com/2304-8158/9/10/1348

Functional beverages constitute the rapidly increasing part of the functional food section and represent an area with a wide range of products including herbal-based beverages. We carried out screening investigations of the extracts of 85 Rosaceous tea plants. Among the extracts analyzed <i>Agrimonia asiatica</i> herb extract demonstrated the highest inhibitory activity against the enzyme α-glucosidase (20.29 µg/mL). As a result of chromato-mass-spectrometric profiling of <i>A. asiatica</i> herb with high-performance liquid chromatography with photodiode array and electrospray triple quadrupole mass-spectrometric detection (HPLC-PDA-ESI-tQ-MS) 60 compounds were identified, including catechins, ellagitannins, flavones, flavonols, gallotannins, hydroxycinnamates, procyanidins, most for the very first time. The analysis of the seasonal variation of metabolites in <i>A. asiatica</i> herb demonstrated that the phenolic content was highest in summer samples and lower in spring and autumn. HPLC activity-based profiling was utilized to identify compounds of <i>A. asiatica</i> herb with the maximal α-glucosidase inhibitory activity. The most pronounced inhibition of α-glucosidase was observed for agrimoniin, while less significant results of inhibition were revealed for ellagic acid and isoquercitrin. The evaluation of phenolic content in <i>A. asiatica</i> herbal teas with the subsequent determination of α-glucosidase inhibiting potential was discovered. Maximum inhibition of α-glucosidase was observed for hot infusion (75.33 µg/mL) and the minimum for 30 min decoction (159.14 µg/mL). Our study demonstrated that <i>A. asiatica</i> herbal tea is a prospective functional beverage in which dietary intake may help to reduce blood glucose.