Metabolites, elemental profile and chemical activities of Pinus strobus high temperature-derived pyroligneous acid

Abstract

AbstractBackgroundPyroligneous acid (PA) is an aqueous smoky fraction produced during pyrolysis of biomass. The chemical composition of PA from different plant biomass has been studied, but reports on PA metabolites and elemental profiles are rare. In this study, we examined the metabolites, elemental profiles and the associated chemical activities of PA derived from white pine (Pinus strobus) at 1100 °C compared to similar work done elsewhere using different biomass at lower temperatures.ResultsPA fromP. strobusbiomass exhibited a lower electrical conductivity (2.05 mS/cm), salinity (1.03 g/L) and total dissolved solids (1.42 g/L) but higheroBrix content (9.35 ± 0.06) compared to PA from other feedstock. TheP. strobusPA showed a higher antioxidant activity characterized by enhanced radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl free-radical (78.52%) and accumulation of higher total phenolic (95.81 ± 1.45 gallic acid equivalents (GAE)/mL) and flavonoid content (49.46 µg quercetin/mL). Metabolite profiling by direct injection mass spectrometry with a reverse-phase liquid chromatography–mass spectrometry (DI/LC–MS/MS) identified a total of 156 metabolites. Four (4) main groups including organic acids (90.87%), hexose (8.60%), carnitine (0.3%) and phospholipids (0.24%) were found in the PA. Mineral element analysis revealed that theP. strobusPA contained high concentrations of nitrogen (N), potassium (K), calcium (Ca) and zinc (Zn), while the content of sodium (Na) and trace/heavy metals were present at levels below the reported limit.ConclusionThis study indicates thatP. strobusPA is a valuable product that can be used in agriculture to improve plant growth and productivity under normal and environmentally stressful conditions.Graphical Abstract