Identification and quantification of cannabinol as a biomarker for local hemp retting in an ancient sedimentary record by HPTLC-ESI-MS

Abstract

Cannabis products have been used in various fields of everyday life for many centuries, and applications in folk medicine and textile production have been well-known for many centuries. For traditional textile production, hemp fibers were extracted from the stems by water retting in stagnant or slow-moving waters. During this procedure, parts of the plant material‚ among them phytocannabinoids‚ are released into the water. Cannabinol (CBN) is an important degradation product of the predominant phytocannabinoids found in Cannabis species. Thus, it is an excellent indicator for present as well as ancient hemp water retting. In this study, we developed and validated a simple and fast method for the determination of CBN in sediment samples using highperformance thin-layer chromatography (HPTLC) combined with electrospray ionization mass spectrometry (ESI-MS), thereby testing different extraction and cleanup procedures‚ as well as various sorbents and solvents for planar chromatography. This method shows a satisfactory overall analytical performance with an average recovery rate of 73%. Our protocol enabled qualitative and quantitative analyses of CBN in samples of a bottom sediment core‚ having been obtained from a small lake in Northern India, where intense local retting of hemp was suggested in the past. The analyses showed a maximum CBN content in pollen zone 4 covering a depth range of 262-209 cm, dating from approximately 480 BCE to 1050 CE. These findings correlate with existing records of Cannabis-type pollen. Thus, the method we propose is a helpful tool to track ancient hemp retting activities.

TLC and HPTLC‐APCI‐MS for the rapid discrimination of plant resins frequently used for lacquers and varnishes by artists and conservators

“…Furthermore, post‐chromatographic detection reactions were performed with cerium‐molybdenum reagent (for the preparation of the cerium‐molybdenum reagent see Schmidt et al 33 ). The reagent was stored in the fridge.…”

Biomarker proxies for reconstructing Quaternary climate and environmental change

“…Other cultivar biomarkers include cannabinol, a marker of hemp that can be used to identify processing activities (retting) from sediment archives (e.g. Lavrieux et al ., 2013; Schmidt et al ., 2020; Rull et al ., 2022), and palmitone, a marker of Colocasia esculenta Schott (taro) (e.g. Krentcher et al, 2019).…”