Natural or artificial: An example of topographic spatial distribution analysis of mescaline in cactus plants by matrix-assisted laser desorption/ionization mass spectrometry imaging

Abstract

IntroductionDifferentiating whether plant products are natural or artificial is of great importance in many practical fields, including forensic science, food safety, cosmetics, and fast-moving consumer goods. Information about the topographic distribution of compounds is an important criterion for answering this question. However, of equal importance is the likelihood that topographic spatial distribution information may provide important and valuable information for molecular mechanism study.MethodsIn this study, we took mescaline, a substance with hallucinogenic properties in cacti of the species Trichocereus pachanoi and Lophophora williamsii, as an example to characterize the spatial distribution of mescaline in plants and flowers by liquid chromatograph-mass spectrometry–matrix-assisted laser desorption/ionization mass spectrometry imaging at the macroscopic, tissue structure, and even cellular levels.ResultsAccording to our results, the distribution of mescaline in natural plant was concentrated on the active meristems, epidermal tissues, and protruding parts of Trichocereus pachanoi and Lophophora williamsii, while artificially spiked Lophophora diffusa products showed no such difference in their topographic spatial distribution.DiscussionThis difference in distribution pattern allowed us to distinguish between flowers that could synthesize mescaline on their own and those that had been artificially spiked with mescaline. The interesting topographic spatial distribution results, such as the overlap of the mescaline distribution map and micrographs of the vascular bundles, were consistent with the synthesis and transport theory of mescaline, indicating the potential for applying matrix-assisted laser desorption/ionization mass spectrometry imaging in botanical research.

How to sample a seizure plant: the role of the visualization spatial distribution analysis of Lophophora williamsii as an example

“…Based on the results of this study, the top part of the crown was the largest enrichment area for mescaline in L. williamsii , which was consistent with our previous results [ 17 ]. In previous studies, we discussed the possible mechanism by which this phenomenon occurs: (i) defensive compounds are found at high levels in vulnerable parts of the plant to build up defenses against foragers; (ii) The mescaline synthetic pathway occurs mainly in neonatal cells, so mescaline is concentrated in areas with dense meristem.…”

“…It has appropriate sensitivity that makes it suitable for many samples in forensic practice [ 13–16 ], but it also has a wide range of resolutions, making it useful for both fine-area (tens of microns) and wide-area imaging. In our previous study, the preliminary spatial distribution of mescaline in various cactus plants was obtained by MALDI-MSI, and the mechanism of mescaline production, transport, and storage was discussed in combination with the other studies [ 17 ].…”

Identification of Markers of Saccharides in Polygonati Rhizoma During the Steaming Process by MALDI-TOF Mass Spectrometry Imaging

“…The slides with tissue sections were placed on the target plate of the mass spectrometer and the target plate was analyzed by using a MALDI-TOF MSI. All MALDI-MSI data were acquired on an iMScope QT instrument (Shimadzu, Kyoto, Japan), which has an integrated optical microscope (magnification ×5, ×10, and ×40), an atmospheric pressure MALDI source, and a quadruple-time-of-flight (Q-TOF) analyzer [31] . The imaging spatial resolution was set to 25 μm for the tissue, and each spectrum consisted of 200 laser shots.…”