Phyllanthurinolactone (1) and phyllurine (2) were isolated from Phyllanthus urinaria L. as bioactive substances for nyctinasty. Compound 1 was quite effective for leaf-closing of the plant at 1 x 10-7 M in the daytime and 2 was quite effective for the leaf-opening at 2.5 x 10-5 M, whereas both 1 and 2 were not effective for other nyctinastic plants even at 1 x 10-4 M. The concentration of 1 increased before leaf-closure in the plant body, whereas that of 2 was constant through a day. Thus, the leaf- movement of P. urinaria L. is proposed to be controlled by the change in the balance of concentration between 1 and 2, which is regulated by a β- glucosidase, similar to the case of Lespedeza cuneata G. Don.
- Biologically active compounds
- Natural products
ASJC Scopus subject areas
- Drug Discovery
- Organic Chemistry