title: Larvicidal and Pupicidal Activities of Alizarin Isolated from Roots of Rubia cordifolia Against Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae).
abstract: The mosquitocidal activities of different fractions and a compound alizarin from the methanol extract of Rubia cordifolia roots were evaluated on larvae and pupae of Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae). Larvae and pupae were exposed to concentrations of 2.5, 5.0, 7.5 and 10 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 h, the mortality was assessed and the LC50 and LC90 values were estimated for larvae and pupae. Among the 23 fractions screened, fraction 2 from the methanol extract of R. cordifolia showed good mosquitocidal activity against C. quinquefasciatus and A. aegypti. LC50 and LC90 values of fraction 2 were 3.53 and 7.26 ppm for C. quinquefasciatus and 3.86 and 8.28 ppm for A. aegypti larvae, and 3.76 and 7.50 ppm for C. quinquefasciatus and 3.92 and 8.05 ppm for A. aegypti pupae, respectively. Further, the isolated compound alizarin presented good larvicidal and pupicidal activities. LC50 and LC90 values of alizarin for larvae were 0.81 and 3.86 ppm against C. quinquefasciatus and 1.31 and 6.04 ppm for A. aegypti larvae, respectively. Similarly, the LC50 and LC90 values of alizarin for pupae were 1.97 and 4.79 ppm for C. quinquefasciatus and 2.05 and 5.59 ppm for A. aegypti pupae, respectively. The structure of the isolated compound was identified on the basis of spectroscopic analysis and compared with reported spectral data. The results indicated that alizarin could be used as a potential larvicide and pupicide.
authors.affiliation: Division of Vector Control, Entomology Research Institute, Loyola College, Nungambakkam, Chennai, 600 034, Tamil Nadu, India.
authors.forename: M R
authors.initials: MR
authors.lastname: Gandhi
authors.affiliation: Division of Vector Control, Entomology Research Institute, Loyola College, Nungambakkam, Chennai, 600 034, Tamil Nadu, India.
authors.forename: A D
authors.initials: AD
authors.lastname: Reegan
authors.affiliation: Division of Vector Control, Entomology Research Institute, Loyola College, Nungambakkam, Chennai, 600 034, Tamil Nadu, India.
authors.forename: P
authors.initials: P
authors.lastname: Ganesan
authors.affiliation: Division of Vector Control, Entomology Research Institute, Loyola College, Nungambakkam, Chennai, 600 034, Tamil Nadu, India.
authors.forename: K
authors.initials: K
authors.lastname: Sivasankaran
authors.affiliation: Division of Vector Control, Entomology Research Institute, Loyola College, Nungambakkam, Chennai, 600 034, Tamil Nadu, India.
authors.forename: M G
authors.initials: MG
authors.lastname: Paulraj
authors.affiliation: Division of Vector Control, Entomology Research Institute, Loyola College, Nungambakkam, Chennai, 600 034, Tamil Nadu, India.
authors.forename: K
authors.initials: K
authors.lastname: Balakrishna
authors.affiliation: Division of Vector Control, Entomology Research Institute, Loyola College, Nungambakkam, Chennai, 600 034, Tamil Nadu, India. eriloyola@hotmail.com.|Visiting Professor Programme, Deanship of Research, King Saud Univ, Riyadh, Saudi Arabia. eriloyola@hotmail.com.
authors.forename: S
authors.initials: S
authors.lastname: Ignacimuthu
authors.affiliation: Dept of Botany and Microbiology, Addiriyah chair for Environmental Studies, College of Science, King Saud Univ, Riyadh, Saudi Arabia.
authors.forename: N A
authors.initials: NA
authors.lastname: Al-Dhabi
mesh_terms: D000330:Aedes; D000818:Animals; D000852:Anopheles; D000880:Anthraquinones / Q000494:pharmacology*; D003465:Culex; D007306:Insecticides; D007814:Larva; D009032:Mosquito Control / Q000379:methods*; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves; D045470:Rubia / Q000737:chemistry*
chemical_list: D000880:Anthraquinones; D007306:Insecticides; D010936:Plant Extracts; C010078:alizarin
keywords: Bioassay; Zika virus; chikungunya; dengue; lymphatic filariasis; mosquito control; sustainable pest control; vector control