title: Acaricidal activity of Cymbopogon citratus and Azadirachta indica against house dust mites.
abstract: OBJECTIVE
  To examine the acaricidal effects of the essential oil of Cymbopogon citratus leaf extract (lemongrass) and ethanolic Azadirachta indica leaf extract (neem) against house dust mites Dermatophagoides farinae (D. farinae) and Dermatophagoides pteronyssinus (D. pteronyssinus).
  
  
  METHODS
  Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations (50.00%, 25.00%, 12.50%, 6.25% and 3.13%) and exposure times (24hrs, 48hrs, 72hrs and 96 hrs). All treatments were replicated 7 times, and the experiment repeated once. The topical and contact activities of the two herbs were investigated.
  
  
  RESULTS
  Mortalities from lemongrass extract were higher than neem for both topical and contact activities. At 50 % concentration, both 24 hrs topical and contact exposures to lemongrass resulted in more than 91% mortalities for both species of mites. At the same concentration and exposure time, neem resulted in topical mortalities of 40.3% and 15.7% against D. pteronyssinus and D. farinae respectively; contact mortalities were 8.0% and 8.9% against the 2 mites, respectively. There was no difference in topical mortalities of D. pteronyssinus from exposure to concentrations of lemongrass and neem up to 12.50%; lemongrass was more effective than neem at the higher concentrations.
  
  
  CONCLUSIONS
  Generally, topical mortalities of D. farinae due to lemongrass are higher than that due to neem. Contact mortalities of lemongrass are always higher that neem against both species of mites.
authors.affiliation: Acarology Unit, Infectious Disease Research Center, Institute for Medical Research, Jalan Pahang, 50588 Kuala Lumpur, Malaysia.
authors.forename: Azima Laili
authors.initials: AL
authors.lastname: Hanifah
authors.forename: Siti Hazar
authors.initials: SH
authors.lastname: Awang
authors.forename: Ho Tze
authors.initials: HT
authors.lastname: Ming
authors.forename: Suhaili Zainal
authors.initials: SZ
authors.lastname: Abidin
authors.forename: Maizatul Hashima
authors.initials: MH
authors.lastname: Omar
mesh_terms: D056810:Acaricides / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D031601:Azadirachta / Q000737:chemistry*; D031743:Cymbopogon / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D039981:Pyroglyphidae / Q000187:drug effects*
chemical_list: D056810:Acaricides; D010936:Plant Extracts
keywords: Acaricidal; Azadirachta indica; Cymbopogon citratus; Dermatophagoides farinae; Dermatophagoides pteronyssinus; House dust mites; Lemongrass; Neem