Using Untargeted LC–MS to Detect and Identify New Lipids in Herbal Tea

A recent study from Hokkaido University in Sapporo, Japan, has unveiled the lipid profiles of four popular herbal teas, revealing new insights into the potential health benefits of these teas. The findings were published in Food Chemistry (1).

Herbal teas have long been revered for their natural bioactive compounds, believed to harbor antioxidant and anticarcinogenic properties. The main difference between regular teas and herbal teas are that herbal teas are made differently (2). Unlike regular teas, herbal teas are made of tisanes, which are blends of several ingredients usually containing dried fruit, flowers, or herbs and spices (2). It is the tisanes that give herbal tea its health benefits.

Cup of herbal tea with linden flowers on dark background | Image Credit: © petrrgoskov - stock.adobe.com.

Although a number of studies have demonstrated that certain teas have therapeutic benefits, the lipidomic composition of herbal teas has remained largely unexplored (1). This study from Japan examines four teas (named dokudami, kumazasa, sugina, and yomogi) to identify 341 molecular species across five major classes of lipids.

The researchers conducted their study by using an untargeted lipidomics approach. Identifying the 341 molecular species required employing high-performance liquid chromatography (HPLC) coupled with linear ion trap-Orbitrap mass spectrometry (1).

The research team then examined each herb to analyze their lipid compositions. By using multivariate principal component analysis (PCA), the team was able to see that each of the herbal teas had different lipid compositions, showing a diverse array of lipids. Of note, kumazasa contained an abundance of α-linolenic acid (FA 18:3), whereas sugina boasted high levels of arachidonic acid (FA 20:4) (1).

The team also observed short-chain fatty acid esters of hydroxy fatty acids (SFAHFAs), which was one of the main highlights of the study. Previously unseen in plants, SFAHFAs are lipids that have not been seen in teas either until now (1). The SFAHFAs uncovered in the herbal teas contained 4-hydroxy phenyl nonanoic acid as the core structure.

This marks the first identification of phenyl-terminated fatty acid derivatives in plants, according to the researchers, opening new avenues for research into their biological significance (1).

The bioactive lipids found in herbal teas, such as α-linolenic acid, have been linked to various health benefits, including anti-inflammatory properties (1). The discovery of SFAHFAs adds to the growing body of evidence supporting the therapeutic potential of herbal teas (1).

Looking ahead, the researchers emphasize the need for further investigation into the biological significance of these unique lipids, both in herbal teas and other food sources (1). Teas have been known to contain certain health benefits. However, this study sheds light on four popular herbal teas, conducting successful lipidomics analysis of them to reveal more about their therapeutic properties.

References

(1) Nath, L. R.; Gowda, S. G. B.; Gowda, D.; et al. Dissection New Lipids and their Composition in Herbal Tea Using Untargeted LC–MS. Food Chem. 2024, 447, 138941. DOI: 10.1016/j.foodchem.2024.138941

(2) Harvard Health, The Health Benefits of Three Herbal Teas. https://www.health.harvard.edu/nutrition/the-health-benefits-of-3-herbal-teas (accessed 2024-04-02).