Analysis of cannabinoids in laser-microdissected trichomes of medicinal Cannabis sativa using LCMS and cryogenic NMR

Nizar Happyana, Sara Agnolet, Remco Muntendam, Annie Van Dam, Bernd Schneider, Oliver Kayser*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

85 Citations (Scopus)

Abstract

Trichomes, especially the capitate-stalked glandular hairs, are well known as the main sites of cannabinoid and essential oil production of Cannabis sativa. In this study the distribution and density of various types of Cannabis sativa L trichomes, have been investigated by scanning electron microscopy (SEM). Furthermore, glandular trichomes were isolated over the flowering period (8 weeks) by laser microdissection (LMD) and the cannabinoid profile analyzed by LCMS. Cannabinoids were detected in extracts of 25-143 collected cells of capitate-sessile and capitate stalked trichomes and separately in the gland (head) and the stem of the latter. Delta(9)-Tetrahydrocannabinolic acid [THCA (1)], cannabidiolic acid [CBDA (2)], and cannabigerolic acid [CBGA (3)] were identified as most-abundant compounds in all analyzed samples while their decarboxylated derivatives, Delta(9)-tetrahydrocannabinol [THC (4)], cannabidiol [CBD (5)], and cannabigerol [CBG (6)], co-detected in all samples, were present at significantly lower levels. Cannabichromene [CBC (8)] along with cannabinol (CBN (9)) were identified as minor compounds only in the samples of intact capitate-stalked trichomes and their heads harvested from 8-week old plants. Cryogenic nuclear magnetic resonance spectroscopy (NMR) was used to confirm the occurrence of major cannabinoids, THCA (1) and CBDA (2), in capitate-stalked and capitate-sessile trichomes. Cryogenic NMR enabled the additional identification of cannabichromenic acid [CBCA (7)] in the dissected trichomes, which was not possible by LCMS as standard was not available. The hereby documented detection of metabolites in the stems of capitate-stalked trichomes indicates a complex biosynthesis and localization over the trichome cells forming the glandular secretion unit. (C) 2012 Elsevier Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)51-59
Number of pages9
JournalPhytochemistry
Volume87
DOIs
Publication statusPublished - Mar-2013

Keywords

  • Cannabis sativa
  • Laser microdissection (LMD)
  • Liquid chromatography-mass spectrometry (LCMS)
  • Cryogenic nuclear magnetic resonance (NMR)
  • Cannabinoid biosynthesis
  • Capitate-stalked trichome
  • Capitate-sessile trichome
  • Gland
  • Scanning electron microscopy (SEM)
  • CONTROLLING MARIJUANA PSYCHOACTIVITY
  • MAGNETIC-RESONANCE-SPECTROSCOPY
  • GLANDULAR TRICHOMES
  • L CANNABACEAE
  • ACID SYNTHASE
  • CANNABIGEROLIC ACID
  • SECRETORY CAVITY
  • PLANT-CELLS
  • CONSTITUENTS
  • BIOSYNTHESIS

Cite this