Quality Evaluation, health risk Assessment, and geographic origin tracing of Ophiocordyceps sinensis through mineral element analysis

Ophiocordyceps sinensis (OS) is a unique and precious medicinal fungus endemic to the Tibetan Plateau, growing underground for the majority of its lifecycle. The mineral composition of OS is a distinctive feature, yet there is currently a lack of comprehensive mineral profiles. The concerns regarding excessive heavy metals and associated health risks significantly impact the development of the OS industry. Furthermore, OS samples from various production areas exhibit distinct qualities, resulting in significant price differences. Mineral profiles hold great potential for origin tracing. Consequently, there is an urgent need for quality evaluation, health risk assessment, and geographic origin tracing of OS by mineral element analysis. Here, 96 OS samples were collected from the representative producing areas in China to investigate their mineral profiles by inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS). Potassium (K) was found to be the most abundant mineral in the OS samples, with a mean content of 10.73 g/kg. High levels of phosphor (P), sulfur (S) and magnesium (Mg) were also detected with concentrations exceeding 1 g/kg. The mean concentrations of total arsenic in all OS samples were determined to be 8.33 mg/kg. The OS from Nagqu exhibited a relatively high quality with lower levels of lead (Pb), cadmium (Cd) and arsenic. Health risk assessment based on the total target hazard quotient (THQ) value of heavy metals of Zn, Mn, Fe, copper (Cu), nickel (Ni), chromium (Cr), Pb and Cd indicated that consumption of OS from China did not pose an obvious risk to human health at the ingestion rate declared by the Chinese Pharmacopeia. Finally, three orthogonal partial least squares discriminant analysis (OPLS-DA) models were constructed using 75 samples to trace the geographic origins. These models successfully authenticated OS samples from six producing areas and confirmed by 21 blind test samples with 90.48 % accuracy. These results affirmed that OS from different regions possessed distinct metal profiles, which could be utilized to authenticate the geographic origins of O. sinensis.