Planta Med 2004; 70(1): 76-78
DOI: 10.1055/s-2004-815462
© Georg Thieme Verlag Stuttgart · New York

In Vitro Antimalarial Activity of Biflavonoids from Wikstroemia indica

Shinyu Nunome1 , Aki Ishiyama2 , Miyuki Kobayashi2 , Kazuhiko Otoguro2 , Hiroaki Kiyohara1 , Haruki Yamada1 , 2 , Satoshi Omura1 , 2
  • 1The Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan
  • 2Research Center for Tropical Diseases, The Kitasato Institute, Tokyo, Japan
This work was supported, in part, by funds from the UNDP/World Bank/WHO special Program for Research and Training in Tropical Disease (grant ID 990 806 and IDA10124), and Grants-in Aid for Scientific Research (A) from the Ministry of Education, Culture, Sports, Science and Technology, Japan. A part of work was supported by the 21st Century COE Program, Ministry of Education, Culture, Sports, Science and Technology (MEXT)
Further Information

Publication History

Received: June 13, 2003

Accepted: October 7, 2003

Publication Date:
06 February 2004 (online)


In our investigation of in vitro antimalarial screening of medicinal herbal extracts, the n-BuOH extract from the root of Wikstroemia indica showed a potent inhibitory effect. Fractionation of the active extract led to the isolation of two biflavonoids, sikokianin B (1) and sikokianin C (2) with IC50 values 0.54 μg/mL and 0.56 μg/mL, respectively, against the chloroquine-resistant strain of Plasmodium falciparum. This is the first report of the biological activity of 1 and 2. As the structure of l has remained unsettled, we confirmed the conformation by 1H- and 13C-NMR.


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