INVESTIGATION OF EXTRACTS OF PLANT-CELL CULTURES BY PROTON NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY

A method for the rapid phytochemical characterization of plant cell cultures, using proton nuclear magnetic resonance spectroscopy (H-1 NMR), is described. Aqueous extracts were prepared from a large number of plant cell suspension cultures. Following lyophilization, the extracts were redissolved in D2O containing an internal standard to enable quantification and H-1 NMR spectra were measured. In the spectra, signals from sugars and amino acids were observed. The patterns obtained were characteristic of cell lines, with related lines typically showing similar characteristics, e.g., Tabernaemontana suspension cultures are characterized by their ability to accumulate large amounts of arginine, while Catharanthus cultures mainly accumulate glutamine. The amounts of amino acids accumulated were found to be determined mainly by the medium on which the cell cultures were growing. Murashige and Skoog medium supported nitrogen storage in amino acids, while Gamborg B5 medium did not. Reference spectra of some of the most common constituents are presented, together with data enabling a direct quantification of these compounds in aqueous extracts.