Microprobing the molecular spatial distribution and structural architecture of feed-type sorghum seed tissue (Sorghum Bicolor L.) using the synchrotron radiation infrared microspectroscopy technique

Abstract

Sorghum seed (Sorghum bicolor L.) has unique degradation and fermentation behaviours compared with other cereal grains such as wheat, barley and corn. This may be related to its cell and cell-wall architecture. The advanced synchrotron radiation infrared microspectroscopy (SR-IMS) technique enables the study of cell or living cell biochemistry within cellular dimensions. The objective of this study was to use the SR-IMS imaging technique to microprobe molecular spatial distribution and cell architecture of the sorghum seed tissue comprehensively. High-density mapping was carried out using SR-IMS on beamline U2B at the National Synchrotron Light Source (Brookhaven National Laboratory, NY, USA). Molecular images were systematically recorded from the outside to the inside of the seed tissue under various chemical functional groups and their ratios [peaks at $ 1725 (carbonyl C O ester), 1650 (amide I), 1657 (protein secondary structure-helix), 1628 (protein secondary structuresheet), 1550 (amide II), 1515 (aromatic compounds of lignin), 1428, 1371, 1245 (cellulosic compounds in plant seed tissue), 1025 (non-structural CHO, starch granules), 1246 (cellulosic material), 1160 (CHO), 1150 (CHO), 1080 (CHO), 930 (CHO), 860 (CHO), 3350 (OH and NH stretching), 2960 (CH 3 antisymmetric), 2929 (CH 2 anti-symmetric), 2877 (CH 3 symmetric) and 2848 cm À1 (CH 2 asymmetric)]. The relative protein secondary structure-helix to-sheet ratio image, protein amide I to starch granule ratio image, and anti-symmetric CH 3 to CH 2 ratio image were also investigated within the intact sorghum seed tissue. The results showed unique cell architecture, and the molecular spatial distribution and intensity in the sorghum seed tissue (which were analyzed through microprobe molecular imaging) were generated using SR-IMS. This imaging technique and methodology has high potential and could be used for scientists to develop specific cereal grain varieties with targeted food and feed quality, and can also be used to monitor the degree of grain maturity, grain damage, the fate of organic contaminants and the effect of chemical treatment on plant and grain seeds.

Vibrational microspectroscopy enables chemical characterization of single pollen grains as well as comparative analysis of plant species based on pollen ultrastructure

“…Spectral signatures of single pollen grains show strong Mie scattering due to their nearly perfect spherical shape (Lukacs et al 2015). In comparison, nearly perfect absorbance spectra have been obtained, when plant materials have been probed by FTIR microspectroscopy as thin sections (Fackler and Thygesen 2013;Yu 2011). Mie scattering signatures are difficult to remove by spectral pre-processing methods.…”

“…Regarding that plant cells are on average some of the largest eukaryotic cells, in general both techniques have sufficient spatial resolution for the analysis of plant cells and tissues. FTIR and Raman have been applied extensively on various plant structures, such as cell walls, seeds, and leaves, for research on plant physiology, developmental biology, genetics and ecology (Gorzsas et al 2011;Barron et al 2005;Dokken et al 2005;Chen et al 2013;Yu 2011;Gierlinger and Schwanninger 2006;Chylińska et al 2014;Agarwal 2006;Fackler and Thygesen 2013;Gierlinger et al 2012). …”

The action of all-trans-retinoic acid (ATRA) and synthetic retinoid analogues (EC19 and EC23) on human pluripotent stem cells differentiation investigated using single cell infrared microspectroscopy

“…A brief review of this area and its potential has recently been published, 18 and a number of other studies have tackled the approach of studying stem cell differentiation in a label-free manner. [19][20][21][22] One such method that is currently being developed is infrared micro-spectroscopy. Infrared spectroscopy of single cells was first demonstrated by Jamin et al 23 in the late 1990s using synchrotron radiation generated infrared as the light source.…”

Study of Barley Grain Molecular Structure for Ruminants Using DRIFT, FTIR-ATR and Synchrotron Radiation Infrared Microspectroscopy (SR-IMS): A Review

“…Yu [5] reported that the advanced Synchrotron-Radiation Infrared MicroSpectroscopy (SR-IMS) is able to study cell or living cell biochemistry within cellular dimension [4]. The author used the SR-…”