Identifying bioactive compounds from switchgrass (panicum virgatum l.) by global metabolomic analysis

Abstract

Untargeted metabolite profiling of switchgrass using cloud metabolomics platform. Integrated biorefining incorporates biomass conversion processes and equipment to produce multiple products including fuels, power, heat, and value-added chemicals from biomass. By identifying multiple high-value products, a biorefinery supply chain can maximize the value derived from the biomass feedstock. The objectives of this study are to 1) to compare the chemical profiles between varieties of switchgrass and 2) to identify and characterize the valued bioactive compounds in switchgrass using global metabolomics approach (XCMS Online). The compounds extracted from switchgrass were analyzed by ultra-high pressure liquid chromatography coupled with high-resolution mass spectrometry (UPLC-HRMS). The ion chromatograms were submitted to XCMS platform operated by Center for Metabolomics at the Scripps Research Institute. The spectra were annotated and the compounds were identified and categorized by the integration of the METLIN, the world's largest metabolite database. Using this platform, we have found 137 putative compounds with various health-promoting bioactivities that have not been reported in switchgrass from the previous studies. Principal component analysis (PCA) was performed for general chemical profiles among varieties, showing that Showme cultivar is similar with Kanlow cultivar. When the analysis is limited to bioactive compounds, the PCA shows that bioactive compounds profiles are significantly different among all four cultivars. The findings from this study suggested that switchgrass could be an excellent source of the raw materials for cosmetic and personal care products industry.