Elevation effect on saikosaponin content in Bupleurum chinense DC taproots and lateral roots

The perennial Bupleurum chinense DC has along medicinal history in China. We selected quadrats at sunny slopes of varied elevations in Dongling Mountains in July and September. Morphological characteristics and saikosaponin content were investigated, SStotal (totalsaikosaponins) yield in taproots and lateral roots and growth characteristics were analyzed along the altitudinal gradient,the ecophysiological adaptive mechanism of Bupleurum chinense DC was thereby discussed. Soil moisture content was found to increase with increasing elevation. Bupleurum chinense DC at high elevations were found to have lowered height and thickened leaves, probably to adapt to strong wind and low temperature. Altitudinal gradient led to varied Bupleurum chinense DC yield and saikosaponin content. Above 1800 m, root biomass and SStotal yield per unit area were the highest, at 1600 m the SStotal content were the highest. SStotal content was higher in lateral roots, independent of elevation.Saikosaponin content varied also with collection period. SStotal content in July was significantly higher than in September. The present work will be useful cultivating and collecting geo-authentic Bupleurum chinense DC.