TY - JOUR
T1 - Comprehensive characterization of the rhizosphere metabolome
T2 - A novel method for non-targeted analysis of Lotus japonicus root exudates
AU - Salomonsen, Camilla
AU - Martyn, Anna
AU - Quilbé, Johan
AU - Björgvinsdóttir, þuríður Nótt
AU - Andersen, Stig U.
AU - Radutoiu, Simona
AU - Glasius, Marianne
PY - 2024/12
Y1 - 2024/12
N2 - Plant root exudates play a pivotal role in shaping soil dynamics and the microbial community in the rhizosphere. The chemical composition of root exudates includes primary and secondary metabolites, including amino acids, organic acids, flavonoids, and small peptides. Comprehensive characterization of root exudates will allow for a better understanding of rhizosphere processes and interactions, but analysis of root exudates is hindered by complicated collection setups, time-consuming sample preparation, and a lack of definitive annotations within metabolomics. We present a method optimized for non-targeted analysis of primary and secondary metabolites in root exudate samples using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry. The method was tested on root exudates from Lotus japonicus, collected using distinct and well-established sampling methods: a hydroponic-soil-hybrid approach, as well as a modification of a soil-leaching method, thus exemplifying the versatility of the analysis method. The method allows for non-targeted screening of plant metabolites, and provides low detection limits (0.002–0.05 μg/mL) and high recoveries (78 ± 30%), though a matrix effect was observed for certain plant metabolites. Detection of a large number of features was achieved (670–2785) of which the majority could be putatively annotated at the compound class level. Of these, 14 features were putatively annotated to a specific structure with high confidence, three of which were confirmed with analytical reference standards. The method can be used for investigation of the overall change in root exudation, as well as for investigating significant changes in metabolites in response to intraenous and extraneous parameters.
AB - Plant root exudates play a pivotal role in shaping soil dynamics and the microbial community in the rhizosphere. The chemical composition of root exudates includes primary and secondary metabolites, including amino acids, organic acids, flavonoids, and small peptides. Comprehensive characterization of root exudates will allow for a better understanding of rhizosphere processes and interactions, but analysis of root exudates is hindered by complicated collection setups, time-consuming sample preparation, and a lack of definitive annotations within metabolomics. We present a method optimized for non-targeted analysis of primary and secondary metabolites in root exudate samples using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry. The method was tested on root exudates from Lotus japonicus, collected using distinct and well-established sampling methods: a hydroponic-soil-hybrid approach, as well as a modification of a soil-leaching method, thus exemplifying the versatility of the analysis method. The method allows for non-targeted screening of plant metabolites, and provides low detection limits (0.002–0.05 μg/mL) and high recoveries (78 ± 30%), though a matrix effect was observed for certain plant metabolites. Detection of a large number of features was achieved (670–2785) of which the majority could be putatively annotated at the compound class level. Of these, 14 features were putatively annotated to a specific structure with high confidence, three of which were confirmed with analytical reference standards. The method can be used for investigation of the overall change in root exudation, as well as for investigating significant changes in metabolites in response to intraenous and extraneous parameters.
KW - Liquid chromatography
KW - Mass spectrometry
KW - Metabolomics
KW - Non-targeted analysis
KW - Root exudates
UR - http://www.scopus.com/inward/record.url?scp=85204002934&partnerID=8YFLogxK
U2 - 10.1016/j.rhisph.2024.100957
DO - 10.1016/j.rhisph.2024.100957
M3 - Journal article
AN - SCOPUS:85204002934
SN - 2452-2198
VL - 32
JO - Rhizosphere
JF - Rhizosphere
M1 - 100957
ER -