Bioassay-guided isolation and identification of Aedes aegypti larvicidal and biting deterrent compounds from Veratrum lobelianum

• Published in: Open Chemistry Vol. 16; no. 1; pp. 324 - 332
• Main Authors: Tabanca, Nurhayat, Ali, Zulfiqar, Bernier, Ulrich R., Epsky, Nancy, Nalbantsoy, Ayse, Khan, Ikhlas A., Ali, Abbas
• Format: Journal Article
• Language: English
• Published: De Gruyter 01.01.2018
• Subjects: fatty ethyl esters; natural products; pest control; phytosterol; stilbenoids
• ISSN: 2391-5420; 2391-5420
• DOI: 10.1515/chem-2018-0030

An ethanol extract from Bernh. rhizomes showed larvicidal activity with LC values of 11.79 ppm and 89.9 ppm against 1 and 4 instar larvae, respectively, at 24 h post-treatment. The extract also showed proportion not biting (PNB) value of 0.76 at 100 μg/cm against females of . . Systematic bioassay-guided fractionation of . extract resulted in the isolation of five compounds that were identified as ethyl palmitate ( ), ethyl linoleate ( ), β-sitosterol ( ), resveratrol ( ) and oxyresveratrol ( ) by GC-MS, H-NMR, and C-NMR techniques, comparison with literature data, and confirmation with authentic compounds. Compound exhibited larvicidal activity with an LC value of 24.1 (22.0-26.2) ppm whereas was inactive. β-Sitosterol ( ) displayed the highest larvicidal activity with LC = 1.7 (1.3-12.3) ppm and LC = 5.1 (3.4-13.8) ppm. Compounds and had larvicidal activity with LC values of 18.5 (15.3-23.3) and 22.6 (19.0-26.8) ppm, respectively, and had an equivalent PNB values of 0.75 at 25 nmol/cm . In addition, and were explored for their human-based repellency against . , attractiveness against male medflies , and also evaluated against series of human carcinoma cells (A549, HEK293, HeLa, SH-SY5Y); however, no significant activity was found.