Natural phenoxazine alkaloids from Peristrophe bivalvis (L.) Merr Trinh Thi Thuy, Tran Hoai Lam, Nguyen Thi Thanh Huong, Le Thi Hong Nhung, Pham Thi Ninh, Nguyen Thi Hoang Anh, Tran Thi Phuong Thao, Tran Van Sung * Institute of Chemistry, Vietnam Academy of Science and Technology,18-Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam article info Article history: Received 20 December 2011 Accepted 19 May 2012 Available online 19 June 2012 Keywords: Peristrophe bivalvis Acanthaceae Phenoxazine Peristrophine Perisbivalvine A 1. Subject and source Peristrophe, a genus of the Acanthaceae family, is distributed in Southern Asia and Africa (Balkwill, 1996; Balkwill et al., 1988). According to the literature there are four Peristrophe species in the Vietnamese flora. One of them Peristrophe bival- vis (L.) Merr., local name “Cẩm” [syn. P. roxburghiana (Schult.) Bremek.; Peristrophe tinctoria (Roxb.) Nees], is growing wildly and cultivated for dying foods as sticky rice and other dishes by the ethnic minorities (Chi, 1999). This species appears in four forms, namely red, purple, purple-magenta, and yellow (the rare form) according to the colours of aqueous extract (Chi, 1999; Trinh et al., 2003). Besides the utilization as food dyestuff, this plant has been used in traditional medicine for the treatment of pulmonary tuberculosis, haemoptysis, congestion, bronchitis and wrench (sprain) (Yang et al., 2002). We investigated the leaves of red and purple P. bivalvis (L.) Merr., two common cultivated forms as a plant to dye food. The plant materials were collected in July 2009 in “Moc Chau steppe”, Son La province of Vietnam and determined by Dr. Ninh Khac Ban, Institute of Ecology and Biological Resources (IEBR), Vietnam Academy of Science and Technology (VAST). Avoucher specimen (No. HN35415) was deposited at the Herbarium of the IEBR, VAST. 2. Previous work Previous phytochemical studies on species of the genus Peristrophe have revealed the presence of aliphatics, 14-methyl- tritriacont-14-en-15-ol, 35-hydroxynonatriacontanal from Peristrophe bicalyculata (Singh et al., 2000); cholest-5-en-3b-oxyl hexadecanoate, octadecanoic acid, palmitic acid, steroids from Peristrophe japonica (Pi et al., 2008) and two alkaloids, peri- strophamide and peristrophine (1) from aerial parts of Peristrophe roxburghiana growing in China (Qin et al., 1999). * Corresponding author. Tel.: þ84 4 37564794; fax: þ84 4 38361283. E-mail address: tranvansungvhh@gmail.com (T. Van Sung). Contents lists available at SciVerse ScienceDirect Biochemical Systematics and Ecology journal homepage: www.elsevier.com/locate/biochemsyseco 0305-1978/$ – see front matter Ó 2012 Elsevier Ltd. All rights reserved. doi:10.1016/j.bse.2012.05.009 Biochemical Systematics and Ecology 44 (2012) 205–207