ABSTRACT
The present study deals with investigation of larvicidal activity and their chemical constituents of the essential oil from the seeds of Nigella sativa L. (Ranunculaceae). Totally, 18 chemical compounds were identified by GC and GC-MS analysis. Thymol (19.13 %) and α-phellandrene (14.9 %) were identified as major chemical components followed by camphor (12.14 %), borneol (11.31 %), and carvacrol (8.65 %). The larval mortality was observed after 12 and 24 h of exposure period. The results revealed that the essential oil were evaluated against the fourth instar larvae of Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. After 12 h of exposure period, the larvicidal activities were LC50 = 196.9 and LC90 = 523.5 ppm (A. aegypti), LC50 = 88.1 and LC90 = 272.4 ppm (A.stephensi), and LC50 = 241.6 and LC90 = 545.4 ppm (C. quinquefasciatus), and the larvicidal activities after 24 h of exposure period were LC50 = 99.9 and LC90 = 300.8 ppm (A. aegypti), LC50 = 53.9 and LC90 = 172.6 ppm (A. stephensi), and LC50 = 141.7 and LC90 = 364.0 ppm (C. quinquefasciatus). The results of the present study showed that the essential oil from seeds of N. sativa is inexpensive food formulation and new source of natural larvicidal agent.
Subject(s)
Aedes/drug effects , Anopheles/drug effects , Culex/drug effects , Insecticides/pharmacology , Nigella sativa/chemistry , Plant Extracts/pharmacology , Animals , Insecticides/chemistry , Larva/drug effects , Mosquito Control , Oils, Volatile , Plant Extracts/chemistry , Plant Oils/chemistry , Plant Oils/pharmacology , Seeds/chemistryABSTRACT
This study was conducted to evaluate the phytochemical composition and larvicidal effect of leaf essential oil from Murraya exotica against early fourth-instar larvae of Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. Gas chromatography (GC) and gas chromatography mass spectrometry (GC-MS) analyses revealed that the essential oil contained 27 components. The major chemical components identified were ß-humulene (40.62%), benzyl benzoate (23.96%), ß-caryophyllene (7.05%) and α-terpinene (5.66%). The larval mortality was observed after 12 and 24 h of exposure period. The results revealed that essential oil showed varied levels of larvicidal activity against A. aegypti, A. stephensi and C. quinquefasciatus. After 12 h of exposure period, the larvicidal activities were LC50 = 74.7 and LC90 = 152.7 ppm (A. aegypti), LC50 = 56.3 and LC90 = 107.8 ppm (A. stephensi ), and LC50 = 74.4 and LC90 = 136.9 ppm (C. quinquefasciatus) and the larvicidal activities after 24 h of exposure period were LC50 = 35.8 and LC90 = 85.4 ppm (A. aegypti), LC50 = 31.3 and LC90 = 75.1 ppm (A. stephensi), and LC50 = 43.2 and LC90 = 103.2 ppm (C. quinquefasciatus). These results suggest that leaf essential oil from M. exotica is a promising and eco-friendly source of natural larvicidal agent against A. aegypti, A. stephensi and C. quinquefasciatus.
