UPLC-QTOF-MS-based metabolomics and chemometrics studies of geographically diverse Acer truncatum leaves: A traditional herbal tea in Northern China.

Traditionally in Northern China, Acer truncatum leaves (ATL) have been used as herbal tea, now consumed worldwide. Few studies have reported ATL metabolites from different areas and their correlation with the environment. Thus, metabolomic analyses were conducted on ATL collected from twelve locations throughout four environmental zones in Northern China to understand the phytochemical differences with regards to environmental conditions. Sixty-four compounds, mostly flavonoids (FLAs) and gallic acid-containing natural products (GANPs), were characterized, including 34 previously unreported constituents from A. truncatum. Twenty-two markers were useful to differentiate ATL from the four environmental zones. Humidity, temperature, and sunshine duration are the predominant factors affecting FLAs and GANPs levels. Sunshine duration was positively correlated with eriodictyol (r = 0.994, p < 0.01), and humidity negatively with epicatechin gallate (r = -0.960, p < 0.05). These findings provide insights into ATL phytochemistry, aiding cultivation of A. truncatum tea with higher potential health benefits.