Abstract:

In order to find the most appropriate macroporous resin to purify total flavonoids from Toona sinensis leaf extract,
the adsorption and desorption performance of nine kinds of macroporous resins for flavonoids from Toona sinensis leaves
were investigated based on adsorption and desorption ratios, and kinetic studies of the static adsorption of flavonoids were
also performed. NKA-9 resin was found to be suitable for the purification of total flavonoids from Toona sinensis leaves. By
using dynamic adsorption and desorption experiments, the optimum purification conditions were obtained as follows: 70 mL
of 7 mg/mL Toona sinensis leaf extract (containing 3 mol/L NaCl) was loaded onto the column at a flow rate of 2 BV/h and
eluted with 80 mL of 60% ethanol (pH 6) at a flow rate of 2 BV/h. Under these conditions, the content of total flavonoids
was increased from 81.272 3 to 219.970 2 mg/g. The results of high performance liquid chromatography (HPLC) analysis
indicated that the contents of rutin, hyperoside, isoquercitrin, quercitrin and afzelinare were increased by more than 3 folds,
respectively, compared with those before purification. The approach presented in this study enables effective enrichment of
total flavonoids from Toona sinensis leaves. Quercitrin, which is two times more abundant than four other compounds, is the
main flavonoid compound from Toona sinensis leaves.

Key words: Toona sinensis leaves, flavonoids, macroporous resin, purification, high performance liquid chromatography (HPLC)