Abstract
Alkaloids are basic nitrogen-containing chemicals that have important physiological and pharmacological characteristics. Many vascular plant species contain alkaloids, and their roles in planta are of interest. However, the detailed distribution of alkaloids remains unclear because of their low water solubility and low concentrations in plants. In this study, we visualized the distribution of salicifoline, a water-soluble quaternary ammonium alkaloid, in the freeze-fixed stems of Magnolia kobus by cryo time-of-flight secondary ion mass spectrometry. Most of the salicifoline was distributed in living phloem tissues. In the xylem, salicifoline was detected in ray cells, lignifying wood fibres, and in vessels in the latest annual ring. The salicifoline distribution in the xylem varied with the cell wall formation stage. These results provide new insights into the storage, transportation, and role of the alkaloid salicifoline in M. kobus.
Highlights
Alkaloids are characteristic chemicals with interesting physiological and pharmacological properties, and they play an important role in the biological functions of plants
Syringin produced secondary ions with m/z of 411.11 for [M + K]+, m/z of 210.09 for its aglycon unit, and m/z of 193.09 for the corresponding [aglycon-OH]+ (Fig. 1c), and their detection intensities were similar. These results show that sinapyl alcohol and syringin were readily distinguished from salicifoline by their potassium adduct ions at m/z 248.04 and 411.11, respectively
The TOF-SIMS visualization displays the apparent concentration of the target chemicals on the measured surface, indicating that the obtained distribution does not show biosynthetic activity at the measured surface
Summary
Alkaloids are characteristic chemicals with interesting physiological and pharmacological properties, and they play an important role in the biological functions of plants. The significant characteristics of alkaloids have been studied using extracted and purified materials; their distribution and roles in planta are not completely understood This poor understanding is partly because of the low concentration of alkaloids in plants and the low water solubility of alkaloids. The distribution of salicifoline in freeze-fixed stems of M. kobus was successfully visualized by cryo-TOF-SIMS/SEM analysis at microscopic resolution. As revealed by our study, in the freeze-fixed stem of M. kobus, salicifoline was distributed in the cortex, secondary phloem and ray cells in the phloem region. The salicifoline distribution in wood fibres and vessels varied with the cell wall formation stage. These results offer new insights for the in planta distribution of the alkaloid salicifoline in M. kobus
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
