A liquid chromatography-mass spectrometry-based method for the quantification of tutin in Coriaria arborea and its application to a longitudinal study

• Tutin can be accurately quantified in leaf, stem, and flower samples. • Growing conditions and location affect tutin levels. • Tutin levels exhibit weak correlation between tissue types. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the quantitative analysis of tutin in tutu ( Coriaria arborea) leaf, flower, and stem samples . Method repeatability of each sample type was found to be acceptable at < 10% relative standard deviation (RSD), and recoveries ranged from 72 – 87 %. On-column detection and quantification limits were determined as 0.15 ng and 0.48 ng respectively. Calibration indicated a linear range across the calibration curve (78.2 – 1484.9 ng/mL) and was maintained across triplicate calibrations spaced across an analytical batch (n = 342). The method was applied to tutu samples ( n = 266) collected from 3 sites in the northern Hawke’s Bay, New Zealand, between May 2021 to August 2022. Results indicated that the highest absolute levels of tutin were detected in a leaf sample at 3.13 mg/g dry weight, although the highest mean concentration was present in flower samples at 1.25 ± 0.61 mg/g dry weight (n = 73; mean ± standard deviation). Sampling location was a statistically significant factor on measured tutin concentration (p = 0.011). Tutin concentration exhibited no easily discernible longitudinal trend, however the concentration was highly variable over time. Overall, the method presented here provides a fast and reliable way to accurately quantify tutin in wild plant populations.