title: Repellant and insecticidal activities of shyobunone and isoshyobunone derived from the essential oil of Acorus calamus rhizomes.
abstract: BACKGROUND
  It was found that the essential oil of Acorus calamus rhizomes showed insecticidal activity.
  
  
  OBJECTIVE
  The aim of this study was to determine the chemical composition of the essential oil from A. calamus rhizomes, evaluate insecticidal and repellant activity against Lasioderma serricorne (LS) and Tribolium castaneum (TC), and to isolate any insecticidal constituents from the essential oil.
  
  
  METHODS
  Essential oil from A. calamus was obtained by hydrodistillation and analyzed by gas chromatography (GC) flame ionization detector and GC-mass spectrometry. The insecticidal and repellant activity of the essential oil and isolated compounds was tested using a variety of methods.
  
  
  RESULTS
  The main components of the essential oil were identified to be isoshyobunone (15.56%), β-asarone (10.03%), bicyclo[6.1.0]non-1-ene (9.67%), shyobunone (9.60%) and methylisoeugenol (6.69%). Among them, the two active constituents were isolated and identified as shyobunone and isoshyobunone. The essential oil showed contact toxicity against LS and TC with LD50 values of 14.40 and 32.55 μg/adult, respectively. The isolated compounds, shyobunone and isoshyobunone also exhibited strong contact toxicity against LS adults with LD50 values of 20.24 and 24.19 μg/adult, respectively, while the LD50 value of isoshyobunone was 61.90 μg/adult for TC adults. The essential oil, shyobunone and isoshyobunone were strongly repellent (98%, 90% and 94%, respectively, at 78.63 nL/cm(2), after 2 h treatment) against TC.
  
  
  CONCLUSIONS
  The essential oil, shyobunone and isoshyobunone possessed insecticidal and repellant activity against LS and TC.
authors.affiliation: College of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600, Liaoning, China.
authors.forename: Hai-Ping
authors.initials: HP
authors.lastname: Chen
authors.affiliation: Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, College of Resources Science and Technology, Beijing Normal University, NO.19 Xinjiekouwai Street, Beijing 100875, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Yang
authors.affiliation: College of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600, Liaoning, China.
authors.forename: Li-Shi
authors.initials: LS
authors.lastname: Zheng
authors.affiliation: Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, College of Resources Science and Technology, Beijing Normal University, NO.19 Xinjiekouwai Street, Beijing 100875, China.
authors.forename: Chun-Xue
authors.initials: CX
authors.lastname: You
authors.affiliation: College of Pharmacy, Liaoning University of Traditional Chinese Medicine, Dalian 116600, Liaoning, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Cai
authors.affiliation: China CDC Key Laboratory of Radiological Protection and Nuclear Emergency, National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, China.
authors.forename: Cheng-Fang
authors.initials: CF
authors.lastname: Wang
keywords: Acorus calamus; Lasioderma serricorne; Tribolium castaneum; contact toxicity; repellency