Traditional herbal remedies and dietary spices from Cameroon as novel sources of larvicides against filariasis mosquitoes?

Abstract

In Cameroon, many dietary spices are used by traditional healers to cure several diseases such as cancer and microbial infections. Aframomum daniellii, Dichrostachys cinerea and Echinops giganteus are Cameroonian spices widely used as flavourings and as food additives. Moreover, they are traditionally herbal remedies employed to treat several diseases, as well as to control populations of insect pests. In this research, we analysed the chemical composition of A. daniellii, D. cinerea and E. giganteus essential oils and we evaluated their larvicidal potential against larvae of the filariasis and West Nile virus vector Culex quinquefasciatus. The essential oils were obtained from different plant parts by hydrodistillation and their composition was analysed by GC-MS. The three spices exhibited different volatile chemical profiles, being characterized by 1,8-cineole, sabinene and β-pinene (A. daniellii), geraniol and terpinen-4-ol (D. cinerea), and silphiperfol-6-ene and presilphiperfolan-8-ol (E. giganteus). Results showed that the highest larvicidal toxicity on Cx. quinquefasciatus was exerted by D. cinerea essential oil (LC 50 = 39.1 μL L −1 ), followed by A. daniellii ) and E. giganteus (LC 50 = 227.4 μL L −1 ). Overall, the chance to use the D. cinerea essential oil against Cx. quinquefasciatus young instars seems promising, since it is effective at moderate doses and could be an advantageous alternative to build newer mosquito control tools.

Trypanosoma brucei Inhibition by Essential Oils from Medicinal and Aromatic Plants Traditionally Used in Cameroon (Azadirachta indica, Aframomum melegueta, Aframomum daniellii, Clausena anisata, Dichrostachys cinerea and Echinops giganteus)

“…This is the first report documenting the antitrypanosomal activity of the tricyclic sesquiterpenes-containing E. giganteus essential oil. The latter was a rich source of compounds such as silphiperfol-6-ene, presilphiperfolan-8-ol, presilphiperfol-7-ene, and cameroonan-7-α-l with an unusual skeleton ( Figure 1 ) [ 26 ]. To date, these compounds have not been biologically investigated.…”

“… a Components are reported in order of their elution from an HP-5MS capillary column; b Retention index (RI) experimentally determined using a mixture of C 8 -C 30 of n-alkanes; c Retention index taken from ADAMS [ 41 ] and/or NIST 08 [ 42 ] for an apolar capillary column; d Relative percentage values are means of three determinations with a Relative Standard Deviation (RSD%) below 15% for the most abundant components; e Analytical data are taken from Pavela et al [ 26 ]; f Identification methods: standard (std), based on the comparison of RT (retention time), RI, and MS (mass spectronomy) with authentic compounds; RI, based on correspondence of calculated RI with those reported in ADAMS and NIST 08; MS, based on comparison with the WILEY, ADAMS, FFNSC2, and NIST 08 MS databases; g traces, % <0.1; h Correct isomer not identified. ID: Identity.…”

“…A. daniellii , also known as ‘African cardamom’, is an herbaceous plant traditionally used in Africa as a spice due to the pungent taste of its seeds, whereas, for medicinal purposes, the plant is employed as a laxative and for curing parasitic and other microbial infections [ 25 , 26 ]. The anti-inflammatory effect of its seed essential oil and the preservative properties in stored grains have also been reported [ 27 , 28 ].…”

“…The root is used for chest complaints and the twigs for gonorrhoea and syphilis. The essential oil was toxic to mosquito vectors of bancroftian filariasis [ 26 ].…”

Chemical composition and antimicrobial activity of essential oils from Aframomum citratum, Aframomum daniellii, Piper capense and Monodora myristica

“…Its seeds are used for flavouring traditional dishes as well as food additives, laxative, anti-helmintic, antibacterial and antifungal agents. The rhizome juice of this plant is effective in the treatment of body odor and toothache (Pamela et al, 2016). The leaves and seeds are used in the treatment of internal and external piles (Focho et al, 2009).…”