PESTICIDAL ACTIVITY OF AN ISOLATED LIMONOID FROM MELIA AZEDARACH L. FRUITS

Ahmed S. Abdel-Aty1 and Ahmed Abdel-Megeed2,3

1Department of Pesticide Chemistry and Technology, Faculty of Agriculture, 21545-El-Shatby, Alexandria University; Alexandria, Egypt.
2 Department of Plant Protection, Faculty of Agriculture, (Saba Basha), Alexandria University, Egypt.
3 Department of  Botany and Microbiology, College of Science, King Saud University, P. O. Box 2455 – Riyadh 11451, Saudi Arabia
Corresponding author E-mail: sabry2000@yahoo.com; aamahmoud@ksu.edu.sa

ABSTRACT

Melia azedarach is one of a famous botanical pesticides source. Extraction of itsfruits with aqueous acetone followed by liquid partitioning with n-butanol, ethanol and methanol lead to a heterocyclic compound (limonoid). Through IR, UV, 1H NMR, 13C NMR, C-H COSY and MS spectroscopic measurements, the isolated compound was identified as 7-(3’-furyl)-benzo[3,4-c]-7H-oxol-2-one. The isolated compound exhibited moderate lethal effects on Spodoptera littoralis 4th larval instar with antifeeding activity increasingly with increasing the tested concentrations with EC50 49.3 and 315 µg/ml after 24 and 48 hours, respectively. Its mortal effect against Culex pipens was increased systematically with LC50 1276, 934 and 257 µg/ml after 1, 2 and 4 days exposure, respectively. It inhibited the treated larvae pupation systematically with 148.7 µg/ml EC50 value. The isolated compound differently inhibited the hyphal growth of plant pathogenic fungi such as Rhizoctonia solani, Macrofomina phaseoli, Pythium debarianum and Fusarium calmorum in a treated fungus and its exposure time dependant effect.
Key-words: Melia azedarach fruits, insecticidal, fungicidal, 7-(3’-furyl)-4-hydroxybenzo[3,4-c]-7H-oxol-2-one, limonoid.