Terpenes isolated from Polyalthia simiarum and their cytotoxic activities.

Two new C triterpenes, polysimiaric acid A (1) and B (2) as well as one new clerodane diterpenoid, 16,16-dimethoxy-cleroda-3,13Z-dien-15-oic acid (3), together with six known compounds were isolated from Polyalthia simiarum. Their structures were determined by analysis of 1D and 2D NMR data. Three new compounds were tested for their cytotoxicity against five human tumour cell lines.

[Improvement effects of quicklime and calcium magnesium phosphate fertilizer on acidified soil cultivating Codonopsis tangshen.].

To solve the problem of soil acidification in the cultivation of Codonopsis tangshen, laboratory experiments were carried out to investigate C. tangshen seed germination, seedling growth and soil exchangeable acid, microbial community structure after applying quicklime (QL) and calcium magnesium phosphate fertilizer (CMP). The results showed that QL and CMP treatments significantly improved the survival rate of C.

[Absorption and Distribution of Nitrogen,Phosphorus and Potassium in Atractylodes macrocephala].

Objective: To investigate the absorption and distribution of nitrogen（ N ), phosphorus（ P） and potassium（ K） in Atractylodes macrocephala by field experiment.

Methods: The samples of Atractylodes macrocephala were carried out in different growing periods,and the amount of dry matter and the contents of N,P and K in different parts of the plant were determined,respectively.

Results: The results showed that one-year-old Atractylodes macrocephala of budding stage and rhizome swelling stage were the key period of rapid nutrient absorption, and the absorbed nutrient element mainly allocated to the aerial part.