Repellency of zerumbone identified in Cyperus rotundus rhizome and other constituents to Blattella germanica

• Published in: Scientific reports 2017-11, Vol.7 (1), p.16643-9, Article 16643
• Main Authors: Chang, Kyu-Sik, Jeon, Jin-Hwan, Kim, Gi-Hun, Jang, Chang-Won, Jeong, Se-Jin, Ju, Young-Ran, Ahn, Young-Joon
• Format: Article
• Language: English
• Subjects: 101/58; 140/131; 631/601/1466; 692/699/255/1318; Animals; Aquatic plants; Behavior, Animal - drug effects; Blattella germanica; Blattellidae - drug effects; Carbonyl compounds; Chemical Fractionation; Cineole; Cockroaches; Cyperus - chemistry; Cyperus rotundus; DEET; Dihydrocarvone; Essential oils; Humanities and Social Sciences; Humulene; Insect Repellents - chemistry; Insect Repellents - isolation & purification; Insect Repellents - pharmacology; Limonene; Male; multidisciplinary; Plant Extracts - chemistry; Plant Extracts - isolation & purification; Plant Extracts - pharmacology; Repellency; Repellents; Rhizome - chemistry; Science; Science (multidisciplinary); Sesquiterpenes - chemistry; Sesquiterpenes - isolation & purification; Sesquiterpenes - pharmacology; Zerumbone
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-16099-6

The compounds 1,8-cineole and zerumbone (ZER) from the Cyperus rotundus rhizome along with another 11 previously identified rhizome essential oil constituents and α-humulene, which lacks the only carbonyl group present in ZER, as well as binary mixtures of ZER and seven active compounds were tested for repellency to male B . germanica . The results were compared to N , N -diethyl-3-methylbenzamide (deet). In filter-paper choice tests, ZER was the most repellent compound, and α-humulene was ineffective, which indicates that the α,β-unsaturated carbonyl group of ZER is a prerequisite component for repellency. At 81.5 μg cm −2 , enhanced repellency was produced by binary mixtures of ZER and 1,8-cineole, (+)-dihydrocarvone or ( R )-(+)-limonene (70:30, 50:50 and 30:70 ratios by weight). These mixtures were very effective against male B . germanica within 24 h and were more repellent than a single compound or deet alone. The optimum ZER content was determined to be more than 50%. In Ebeling choice box tests at 652.4 μg cm −2 , these compounds and deet resulted in complete repellency to intact male B . germanica , while they exhibited 35–47% repellency to antennectomized male one. Mixtures formulated from the active constituents of the C . rotundus rhizome could be useful as potential repellents for controlling B . germanica .