Essential Oils from Cameroonian Aromatic Plants as Effective Insecticides against Mosquitoes, Houseflies, and Moths

Abstract

Recently, spices have attracted the attention of scientists and agrochemical companies for their potential as insecticidal and acaricidal agents, and even as repellents to replace synthetic compounds that are labeled with detrimental impacts on environment and human and animal health. In this framework, the aim of this study was to evaluate the insecticidal potential of the essential oils (EOs) obtained from three Cameroonian aromatic plants, namely Monodora myristica (Gaertn.) Dunal, Xylopia aethiopica (Dunal) A. Rich., and Aframomum citratum (J. Pereira) K. Schum. They were produced by hydrodistillation, with yields of 3.84, 4.89, and 0.85%, respectively. The chemical composition was evaluated by GC-MS analysis. The EOs and their major constituents (i.e., geraniol, sabinene, α-pinene, p-cymene, α-phellandrene, and β-pinene) were tested against the polyphagous moth pest, i.e., Spodoptera littoralis (Boisd.), the common housefly, Musca domestica L., and the filariasis and arbovirus mosquito vector, Culex quinquefasciatus Say. Our results showed that M. myristica and X. aethiopica EOs were the most effective against M. domestica adults, being effective on both males (22.1 µg adult−1) and females (LD50: 29.1 µg adult−1). The M. myristica EO and geraniol showed the highest toxicity on S. littoralis, with LD50(90) values of 29.3 (123.5) and 25.3 (83.2) µg larva−1, respectively. Last, the EOs from M. myristica and X. aethiopica, as well as the major constituents p-cymene and α-phellandrene, were the most toxic against C. quinquefasciatus larvae. The selected EOs may potentially lead to the production of cheap and effective botanical insecticides for African smallholders, although the development of effective formulations, a safety evaluation, and an in-depth study of their efficacy on different insect species are needed.

Chemical Constituents and Antimicrobial and Antioxidant Activities of Essential Oil from Dried Seeds of Xylopia aethiopica

“…Finally, trans-pinocarveol [ 27 , 35 ], myrtenol [ 27 ], α -pinene [ 19 , 36 , 44 ], and terpinen-4-ol [ 7 , 37 ] have been reported in a certain number of studies. Germacrene D [ 17 ], eugenol [ 20 ], sabinene [ 30 , 41 – 43 ], 4-isopropylbenzyl alcohol [ 44 ], 3-carene [ 45 ], and santalol [ 46 ] were found in certain essential oils of X. aethiopica fruits at significant levels while in our sample, they were present in low or no levels. This chemical variability may be due to climatic conditions, soil conditions, and genetic mutations.…”

Toxicity of plants as insecticides against human pathogenic mosquito vectors of Saudi Arabian strains—A review

“…Besides secondary metabolites of plants, essential oils from plant based origin are considered to be good mosquitocidal agent (Senthil-Nathan 2020;Yohana et al 2022). Essential oils obtained from aromatic plants, namely Monodora myristica, Xylopia aethiopica, Aframomum citratum (Nkuimi Wandjou et al 2022), medicinal plants Cymbopogon nardus, Eucalyptus globulus, Mentha arvensis, Citrus limon and Trachyspermum ammi (Kamaraj et al 2023), weeds Mikania scandens (Radhakrishnan et al 2023).…”

“…Essential oils obtained from aromatic plants, namely Monodora myristica , Xylopia aethiopica , Aframomum citratum (Nkuimi Wandjou et al . 2022), medicinal plants Cymbopogon nardus , Eucalyptus globulus , Mentha arvensis , Citrus limon and Trachyspermum ammi (Kamaraj et al . 2023), weeds Mikania scandens (Radhakrishnan et al .…”

Insecticidal Activity of Plant Secondary Metabolites

“…Kostić et al [ 5 ] tested three Apiaceae essential oils, namely anise ( Pimpinella anisum ), dill ( Anethum graveolens ) and fennel ( Foeniculum vulgare ) against Lymantria dispar, showing them as potential agents for gypsy moth control. Giordani et al [ 6 ] and Wandjou et al [ 7 ] outlined the promising toxicity of essential oils extracted from Chilean Patagonian and Cameroonian plant species against insects of agricultural ( Spodoptera littoralis ) and public health importance ( Culex quinquefasciatus and Musca domestica ). Repellent effects of plant-borne secondary metabolites on hard ticks .…”