Study on Effects of Seasonal and Regional Differences on Secondary Metabolites of Eucommia ulmoides Oliv. Leaves

To study effects of differences among seasonal and region on three bioactive components,namely geniposidic acid(GA),chlorogenic acid(CA) and geniposide(G),in Eucommia ulmoides Oliv.leaves,reversed-phase high-performance liquid chromatograpy(HPLC) was used to analyse the three secondary metabolites from E.ulmoides leaves.Results show:the content of the three components was highest in June,which reached 0.562 %,2.258 % and 0.571 %,respectively,indicating June to be the best harvest period for collecting leaves.In addition,significant regional difference affects also the accumulation of the products,which disclosed that the worse climate conditions with annual average temperature 6.8-8.8 ℃,annual Absolute lowest humidity from-29.6 % to-22.6 %,and annual rainfall 576.7-1 048 mm resulted in high yield of the secondary metabolites in the same species of E.ulmoides.June was the best harvest period for collecting leaves.The climate conditions significantly affected the content of the secondary metabolites in E.ulmoides leaves.