2.5 Analysis of flavonoids and phenolic acid compounds.
Briefly (D. Li et al., 2021), wheat leaves (100mg) were ground to the powder in liquid nitrogen. They were added 1mL water (containing 60% ethanol) in a centrifuge tube. The solution was used ultrasound for 30min at 30℃ and then centrifuged for 5min at 12000rpm. The concentration was collected by conducting twice operating method. The mixture was collected and blown dry with nitrogen. The final volume was 1mL with the above solution and centrifuged for 1min at 10000rpm. It was purified with 100mg C18 in 2mL centrifuge tube, shake for 2min and centrifuged for 1 minute at 10000 rpm. Next, the supernatant was filtered into the injection vial by 0.22μm nylon syringe. HPLC-MS/MS (Agilent 6410B triple quadrupole) was used to analyze the concentration. The parameter was showed in Table S2 and Table S3.