In situ Identification of Labile Precursor Compounds and their Short-lived Intermediates in Plants using in vivo Nanospray High-resolution Mass Spectrometry.
BACKGROUND
Many secondary metabolites in plants are labile compounds which under environmental stress, are difficult to detect and track due to the lack of rapid in situ identification techniques, making plant metabolomics research difficult. Therefore, developing a reliable analytical method for rapid in situ identification of labile compounds and their short-lived intermediates in plants is of great importance.


OBJECTIVE
To develop under atmospheric pressure, a rapid in situ method for effective identification of labile compounds and their short-lived intermediates in fresh plants.


METHODS
An in vivo nanospray high-resolution mass spectrometry (HR-MS) method was used for rapid capture of labile compounds and their short-lived intermediates in plants. A quartz capillary was partially inserted into fresh plant tissues, and the liquid flowed out through the capillary tube owing to the capillary effect. A high direct current (d.c.) voltage was applied to the plant to generate a spray of charged droplets from the tip of the capillary carrying bioactive molecules toward the inlet of mass spectrometer for full-scan and MS/MS analysis.


RESULTS
Many labile compounds and short-lived intermediates were identified via this method: including glucosinolates and their short-lived intermediates (existing for only 10 s) in Raphanus sativus roots, alliin and its conversion intermediate (existing for 20 s) in Allium sativum and labile precursor compound chlorogenic acid in Malus pumila Mill.


CONCLUSIONS
The method is an effective approach for in situ identification of internal labile compounds and their short-lived intermediates in fresh plants and it can be used as an auxiliary tool to explore the degradation mechanisms of new labile plant compounds. Copyright © 2016 John Wiley & Sons, Ltd.
Faculty of Earth Sciences, China University of Geosciences, Wuhan, China.
Qing
Q
Chang
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan, China.
Yue'e
Y
Peng
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan, China.
Bin
B
Shi
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan, China.
Conghui
C
Dan
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China.
Yijun
Y
Yang
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan, China.
Qin
Q
Shuai
D060166:Capillary Tubing; D002726:Chlorogenic Acid / Q000737:chemistry* / Q000302:isolation & purification; D003545:Cysteine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification; D005737:Garlic / Q000737:chemistry*; D005961:Glucosinolates / Q000737:chemistry* / Q000302:isolation & purification; D027845:Malus / Q000737:chemistry*; D055432:Metabolomics; D015394:Molecular Structure; D018517:Plant Roots / Q000737:chemistry; D011791:Quartz; D031224:Raphanus / Q000737:chemistry*; D013312:Stress, Physiological; D053719:Tandem Mass Spectrometry; D013997:Time Factors
D005961:Glucosinolates; D011791:Quartz; D002726:Chlorogenic Acid; C006453:alliin; D003545:Cysteine
conversion mechanism; high-resolution mass spectrometry (HR-MS); in vivo nanospray; labile compounds; seconds timescale