Quantitative visualization of lignocellulose components in transverse sections of moso bamboo based on FTIR macro- and micro-spectroscopy coupled with chemometrics

Abstract

BackgroundDue to the increasing demands of energy and depletion of fossil fuel, bamboo is considered to be one of the most important renewable biological resources on the basis of its advantages of rapid growth ability and rich reserves. Cellulose, hemicellulose, and lignin are the three most important constituents in moso bamboo. Their concentrations and, especially, their microscopic distributions greatly affect their utilization efficiency and other physical properties as a biomass resource. However, no studies have achieved a quantitative visualization of the distribution of lignocellulose concentrations in transverse sections of bamboo. Therefore, this study proposed the use of quantitative multivariate spectral analysis to reveal the micro-chemical distribution of lignocelluloses in bamboo based on an integration of FTIR macro- and micro-spectroscopic imaging techniques.ResultsMultivariate calibration models for the quantitative determination of lignocelluloses of bamboo were developed based on FTIR macro-spectroscopy, and the quantitative calibration models based on the FTIR characteristic bands showed an excellent performance with determination coefficients of 0.933, 0.878, and 0.912 for cellulose, hemicellulose, and lignin, respectively. These quantitative models were then utilized to the FTIR micro-spectroscopy of bamboo transverse sections which were corrected using a direct standardization algorithm. Subsequently, the micro-chemical distributions of cellulose, hemicellulose, and lignin were obtained based on the integration of the multivariate calibration models and corrected FTIR micro-spectroscopy. The combination of the multivariate calibration models and calibration transfer algorithm resulted in a final quantitative visualization of the chemical distributions of lignocelluloses in moso bamboos.ConclusionsIntegration of the FTIR macro- and micro-spectroscopic imaging techniques can provide comprehensive information that can be used to exploit the resource of moso bamboo to develop biofuels and biosynthetic materials.

Comparing chemical composition and lignin structure of Miscanthus x giganteus and Miscanthus nagara harvested in autumn and spring and separated into stems and leaves

“…Here, multivariate data processing (such as partial component analysis, linear discriminant analysis, factorial discriminant analysis and partial least squares-discriminant analysis) proved to be a useful tool for origin specication of complex structures such as lignocellulosic biomass, especially lignin. 71,72,[93][94][95][96][97][98][99] Moreover, Brandt et al emphasized that quantication using HSQC is generally limited since pulse sequences are usually optimized for resolution and signal strength. In addition, signal relaxation might not be complete particularly for some slowly relaxing end groups.…”

Low-Input Crops as Lignocellulosic Feedstock for Second-Generation Biorefineries and the Potential of Chemometrics in Biomass Quality Control

“…In our ongoing research, XRF (in addition to spectroscopic methods) is used for quantitative biomass analysis, with respect to heavier elements that can be a marker of certain features and in combination with machine learning methods for ascertaining the type and origin of LCF. In Table 3, a variety of studies reporting the structure and composition analysis of LCF, using experimental analytical methods combined with multivariate data processing, are summarized [134][135][136][137][138][139][140][141][142][143].…”

“…The samples (15 stalks of five ages) were collected from three different sites in China, including Jingning and Guangan counties, Sichuan Province. FTIR macro-and micro-spectroscopic imaging techniques, combined with chemometric processing (using partial least-squares regression (PLSR) and Monte Carlo sampling to identify abnormal data), have been applied for quantitative analysis of moso bamboo crop composition [136].…”

Quantitative visualization of subcellular lignocellulose revealing the mechanism of alkali pretreatment to promote methane production of rice straw

“…The development of micro-spectrometers, which fuse the chemical specificity of vibrational spectrums with the power of optical magnification by the acquirement of high-quality spectra with subcellular resolution, has also contributed to further exploitation and utilization of biomass [2]. Microscopy based on infrared absorption offers chemical specificity, but the spatial resolution is limited by long infrared wavelengths, and the penetration depth into aqueous plant samples is limited [12,13]. Raman microspectroscopy with advantages such as label-free chemical contrast, high spatial resolution, and chemical specificity, which are free from water disturbance, has been widely used in visualizations of subcellular lignocellulose [14].…”