Cytotoxic screening of medicinal and edible plants in Okinawa, Japan, and identification of the main toxic constituent of Rhodea japonica (Omoto).
The cytotoxic activity of ethanol extracts from 53 parts of 36 species of medicinal and edible plants cultivated in Okinawa was measured by using K562 human leukemia cells by a flow cytometric method. Two extracts from Rhodea japonica and Hypericum chinense were cytotoxic at a concentration of 10 microg/ml. The main cytotoxic constituent of Rhodea japonica was isolated and identified to be rhodexin A, which has been isolated as a cardetonic agent of the plant. The IC(50) value for rhodexin A against the growth of K562 cells was 19 nM, this activity being much stronger than that of ouabain (IC(50), 60 nM).
Masuda
Toshiya
T
Faculty of Integrated Arts and Sciences, University of Tokushima, Tokushima 770-8502, Japan. masuda@ias.tokushima-u.ac.jp
Oyama
Yasuo
Y
Yamamoto
Natsuko
N
Umebayashi
Chisato
C
Nakao
Hiromi
H
Toi
Yukiko
Y
Takeda
Yoshio
Y
Nakamoto
Katsuo
K
Kuninaga
Hideki
H
Nishizato
Yukari
Y
Nonaka
Akira
A
D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D005434:Flow Cytometry; D006801:Humans; D020902:Hypericum / Q000737:chemistry; D020128:Inhibitory Concentration 50; D007564:Japan; D020014:K562 Cells; D010936:Plant Extracts / Q000032:analysis; D010945:Plants, Edible / Q000737:chemistry* / Q000633:toxicity; D010946:Plants, Medicinal / Q000737:chemistry* / Q000633:toxicity; D014118:Toxins, Biological / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
D000970:Antineoplastic Agents; D010936:Plant Extracts; D014118:Toxins, Biological