High Resolution 31P NMR Spectroscopy Generates a Quantitative Evolution Profile of Phosphorous Translocation in Germinating Sesame Seed

Abstract

Phosphorus metabolism and circulation are essential bio-physicochemical processes during development of a plant and have been extensively studied and known to be affected by temperature, humidity, lighting, hormones etc. However, a quantitative description of how various phosphorous species evolve over time has not been reported. In this work, a combined 31P liquid and solid state NMR spectroscopic methodology is employed, supported by a new extraction scheme and data analysis method, to carry out a quantitative investigation of phosphorous circulation in germinating sesame seeds in dark and under illumination with and without adding a growth hormone. The spectra show that only slight changes occur for phosphorous metabolism at the initial stage but a rapid change takes place between 48–96 hours after germination is started. The metabolism is found to be temperature dependent and affected by illumination and hormone. However, neither illumination nor hormone affects the final residual concentration of phytin. Moreover, phytin does not flow out of cotyledon and the phosphorous flowing to other parts of the plant is always in the inorganic form. The overall evolution profile of phytate consumption is found to be a Gaussian decaying function. These findings can be explained with a dynamic model on phytin conversion.

Phosphonates as Unique Components of Plant Seeds—A Promising Approach to Use Phosphorus Profiles in Plant Chemotaxonomy

“…In comparison other analytical techniques, 31 P NMR is a valuable tool for the detailed characterisation of all P species, including inorganic and organic P forms, without the need for any complex cleaning and prefractionation procedures. Despite that, phosphorus speciation of seed extracts by 31 P NMR spectroscopy is poorly described in the literature [ 15 , 19 ]. Our research was based on this technique and enabled the phosphorus profiles of many kinds of seeds belonging to different families to be characterised, while taking into account the proportion of phosphonates.…”

“…The integration of peak areas was calculated on spectra processed with a line broadening of 2 Hz. 31 P NMR signal assignments were based on literature data [ 15 , 24 ]. The relative P concentrations in the neutralised extracts were estimated based on the total NMR signal area and presented as the percentage of each species using TopSpin version 3.6.2 software.…”

“…Data regarding naturally occurring phosphonate compounds relate mainly to structures isolated from microorganisms (bacteria, cyanobacteria, fungi) and animals [ 6 ]. Although qualitative and quantitative research on phosphorus compounds in plant organs and tissues has been described many times [ 13 , 14 , 15 ], the presence of phosphonates in plant materials has been confirmed only sporadically. The only reports of phosphonic compounds present in plants come from the 1980s.…”

31P NMR Investigations on Roundup Degradation by AOP Procedures

“…These not always coherent results ( Figure 1) led us to investigate these process by using 31 P NMR monitoring of the PMG degradation processes. This 31 P NMR technique has been applied for the analysis of PMG metabolites and degradation products in only a few earlier research works [26][27][28][29][30][31][32][33]. chemicals by the consumption of contaminated water [16][17][18][19][20][21][22][23][24][25][26].…”

Functional Genomics Approaches to Studying Symbioses between Legumes and Nitrogen-Fixing Rhizobia

“…NMR is superior in structural elucidation and can discriminate between molecules with the same mass, and its quantification of compounds in complex mixtures is very precise [ 127 ]. Furthermore, NMR offers the possibility of tracking metabolite dynamics intracellularly and in vivo [ 128 ]. On the other hand, MS is generally more sensitive and enables the simultaneous distinction of more metabolites, up to thousands of features with high-resolution instruments such as time-of-flight (TOF) or Orbitrap [ 125 , 129 ].…”