Larvicidal and repellent activity of N-methyl-1-adamantylamine and oleic acid a major derivative of Bael tree ethanol leaf extracts against dengue mosquito vector and their bio-safety on natural predator

Authors: CHELLAPPANDIAN, MUTHIAH - Manonmaniam Sundaranar University (MSU); SENTHIL-NATHAN, SENGOTTAYAN - Manonmaniam Sundaranar University (MSU); KARTHI, SENGODAN - Manonmaniam Sundaranar University (MSU); VASANTHA-SRINIVASAN, PRABHAKARAN - St Peter’s Institute Of Higher Education And Research; KALAIVANI, KANDASWAMY - Sri Parasakthi College For Women; Hunter, Wayne; ALI, AJMAL - King Saud University; VEERABAHU, CHOCKALINGAM - Vochidambaram College; SOLIMAN ELSHIKH, MOHAMED - King Saud University; AL FARRAJ, DUNIA - King Saud University

Submitted to: Environmental Science and Pollution Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/24/2021
Publication Date: 10/11/2021
Citation: Chellappandian, M., Senthil-Nathan, S., Karthi, S., Vasantha-Srinivasan, P., Kalaivani, K., Hunter, W.B., Ali, A.B., Veerabahu, C., Soliman Elshikh, M., Al Farraj, D.A. 2021. Larvicidal and repellent activity of N-methyl-1-adamantylamine and oleic acid a major derivative of Bael tree ethanol leaf extracts against dengue mosquito vector and their bio-safety on natural predator. Environmental Science and Pollution Research. 29, 15654–15663. https://doi.org/10.1007/s11356-021-16219-w.
DOI: https://doi.org/10.1007/s11356-021-16219-w

Interpretive Summary: New chemistries are needed for mosquito management to reduce transmitted diseases. We identified natural plant compounds may provide suitable treatments to suppress mosquito and other insect pests. The “Bael fruit tree” (Family: Rutaceae) occurs across south Asian countries. Derivatives from crude ethanolic extracts of Bael tree leaves had insecticidal activity on the larvae of Dengue mosquito vector Aedes aegypti (L.) (Family: Culicidae) while having low toxicity to the mosquito’s predator, Toxorhynchites splendens (Family: Culicidae). Two major compounds were identified in the extract, N-Methyl-1-adamantaneacetamide (N-M1a) (63.1%) and Oleic acid (OA)(11.43%) respectively. Mosquito larvae mortality was (93.6%) at the maximum dosage of 100 ppm of extract, while the repellency at (50 ppm) was like the pure compound controls (N-M1a and OA) with maximum protection of 3.5 hours. Meanwhile the extract, and controls, N-M1a and OA, treatments on the mosquito predator Tx. splendens showed low toxicity even at increased dosage of 1000 ppm (34.1%). The present investigation clearly showed that crude ethanol extract of Bael leaves and their major derivatives N-M1a, and OA have acute larval toxicity, with potential repellency against the dengue mosquito while being relatively safe on the mosquito’s predator. Further research to formulate a suitable product may provide new mosquitocides and repellents, while also being suitable to treat other insect pests.

Technical Abstract: The “Bael fruit tree” Aegle marmelos (L.) Correa –(Family: Rutaceae) occurs across south Asian countries. Derivatives from crude ethanolic extracts of the Bael tree leaf had insecticidal activity on the Dengue mosquito vector Aedes aegypti (L.) (Family: Culicidae) while having low toxicity to the mosquito predator Toxorhynchites splendens (Family: Culicidae). The GC-MS analyses showed the peak area to be N-methyl-1-adamantaneacetamide (N-M1a) followed by oleic acid (OA) at 63.1% and 11.4% respectively. The fourth instar larvicidal activity was (93.6%) at the maximum dosage of 100 ppm. Significant mortality occurred with N-M1a and OA at 10 ppm (97.7%) and 12 ppm (95.4%) respectively. Repellency of the crude extract was prominent at (50 ppm) as compared to the pure compound controls (N-M1a and OA) with maximum protection of 210 minutes (3.5 hours). The non-target screening of extract, and controls N-M1a, and OA on the mosquito predator Tx. splendens showed low toxicity even at a dosage of 1000 ppm (34.1%), 100 ppm (27.3%), and 120 ppm (31.3%) respectively. Further research to formulate these compounds into a suitable product may provide new mosquitocides and repellents, while also being suitable to treat other insect pests.