Effect Of Exogenous Salicylic Acid On The Content Of Camptothecin In Camptotheca Acuminata Seedlings.

Camptothecin (CPT) is an anti-cancer terpenoid indole alkaloid. It was mainly extracted from Camptotheca acuminata which is a native tree of China. Salicylic acid is an important signal molecular in plant chemistry defence system. An improved extraction method of endogenous salicylic acid was established. And on the basis of that, variation of salicylic acid and camptothecin content in Camptotheca acuminata organs was investigated after the treatment through leaves or roots.with salicylic acid. The results are as follows:1. Exogenous salicylic acid treatment contributed to an increase of salicylic acid content in treated organ and stem. Some of free salicylic acid may be transformed into conjugated salicylic acid for storage, but the amount was limited. The concentration of free salicylic acid decrease quickly, while conjugated salicylic acid kept a high level for a long time. When the seedlings were treated through roots, the content of salicylic acid in leaves also got enhance, but when the seedlings were treated through leaves, the content of salicylic acid in roots kept still.2. Exogenous salicylic acid treatment through the leaves resulted in obvious increase of CPT in young leaves. While the content of CPT in upper mature leaves increased in last sampling (day 12), the content of CPT in lower mature leaves didn't changed, and there was a little increase in roots.Exogenous salicylic acid treatment through the roots didn't result in variation of CPT in young leaves. The variation of CPT content was complex in the mature leaves and roots. CPT content get increased in latter sampling (day 12) in all the organs.