Abstract: Non-saponifiable matter of polyprenols from Ginkgo biloba L. was obtained by saponification,extraction and solvent refrigeration, using 5% NaOH-EtOH as saponifier,ratio of paste of petroleum ether to saponifier 1:5(g:mL).Molecular short distillation was first used to purify non-saponifiable matter of polyprenols. For the I grade molecular distillation, the optimum operation parameters were: condensation temperature 2.5℃, circulating-water temperature 60℃, feed temperature 60℃,distillation temperature 160℃,feed flow rate 180mL/h,scraper rate 200r/min,operation pressure 0.5--0.5Pa. The results showed that content of polyprenols in solution was raised to 55.6%,recovery rate of polyprenols from G. biloba L.(GP) was 98.5%, content of polyprenols in distillate residue could be raised from 46.2% to 83.7% of non-saponifiable matter, and there was no solvent residue. Thus, this mehod would be an ideal separation method to prepare high-purity polyprenols industrially.

Key words: leaves of Ginkgo biloba L, polyprenols, non-saponifialble matter, molecular short distillation