Bioactive Molecules Derived from Plants in Managing Dengue Vector Aedes aegypti (Linn.)

Abstract

Mosquitoes are the potential vectors of several viral diseases such as filariasis, malaria, dengue, yellow fever, Zika fever and encephalitis in humans as well as other species. Dengue, the most common mosquito-borne disease in humans caused by the dengue virus is transmitted by the vector Ae. aegypti. Fever, chills, nausea and neurological disorders are the frequent symptoms of Zika and dengue. Thanks to various anthropogenic activities such as deforestation, industrialized farming and poor drainage facilities there has been a significant rise in mosquitoes and vector-borne diseases. Control measures such as the destruction of mosquito breeding places, a reduction in global warming, as well as the use of natural and chemical repellents, mainly DEET, picaridin, temephos and IR-3535 have proven to be effective in many instances. Although potent, these chemicals cause swelling, rashes, and eye irritation in adults and children, and are also toxic to the skin and nervous system. Due to their shorter protection period and harmful nature towards non-target organisms, the use of chemical repellents is greatly reduced, and more research and development is taking place in the field of plant-derived repellents, which are found to be selective, biodegradable and harmless to non-target species. Many tribal and rural communities across the world have been using plant-based extracts since ancient times for various traditional and medical purposes, and to ward off mosquitoes and various other insects. In this regard, new species of plants are being identified through ethnobotanical surveys and tested for their repellency against Ae. aegypti. This review aims to provide insight into many such plant extracts, essential oils and their metabolites, which have been tested for their mosquitocidal activity against different life cycle forms of Ae. Aegypti, as well as for their efficacy in controlling mosquitoes.

Keywords: Aedes aegypti; adulticidal; larvicidal; metabolites; non-target toxicity; ovicidal; oviposition deterrent; plant crude extracts; pupicidal.

Figure 1

Life Cycle of Aedes aegypti.

Figure 2

Mode of action of plant metabolites on mosquito gut cells.

Figure 3

Chemical structures of major metabolites detected in larvicidal plants [72,73,74,75,76,77,78]. (A) trans-anethole, (B) limonene, (C) terpinen-4-ol, (D) carvacrol, (E) thymol, (F) p-cymene, (G) γ-terpinene, (H) rolliniastatin-1, (I) rollinicin, (J) α-terpinene, (K) citral, (L) citronellal, (M) citronellyl acetate, (N) eugenol, (P) geraniol, (Q) isopulegol, (Q’) CDIAL, (R) CML, (S) CMOS, (T) CFRAG, (a) 2,6,10,14,18,22-tetracosane hexane, (b) 2,6,10,15,19,23-hexamethyltetracosane, (c) 3-cyclohexene-1-methanol,.alpha., .alpha.4-trimethyl, (d) α-phellandrene, (e) carvone, (f) d-limonene, (g) estragole, (h) eugenyl acetate, (i) niloticin, (j) rotundifolone, (k) sabinene, (m) tetracontane, (n) 1,8-cineole, (o) α-pinene, (p) β-myrcene, (q) CPCD, (r) citronellol, (s) phthalide, (s’) POLYG, (t) elemol, (u) WARB, (v) UGAN, (w) geranial, (y) neral.

Figure 4

(A) Dengue mosquitoes use chemical cues to find a host and feed. Also, plant repellents with different phytocompounds with different modes of action. (B) Repellent’s response to specific molecular targets including sensory receptors (odorant receptor (OR), gustatory receptor (GR) and ionotropic receptor (IR)) distributed on various arthropod appendages. Future insect repellents may interact with other receptor families including the transient receptor potential channel (TRP), pickpocket receptor (PPK) and G-protein-coupled receptor (GPCR). (C) Sensory appendages of mosquito vector.

Figure 5

Chemical structures of major metabolites detected in plants showing repellency [74,75,77]. (A) 2-methoxy-4-vinyl alcohol, (B) 6,10,14-trimethyl-2-pentadecanone, (C) ⍺-pinene, (D) ⍺-terpineol, (E) β-myrcene, (F) β-phellandrene, (G) butylidene phthalide, (H) butylphthalide, (I) calotoxin, (J) carvacrol, (K) cis and trans-β-ocimene, (L) cis-carveol, (M) cis-tagetenone, (N) citral, (O) citronellol, (P) coumarin, (Q) diisooctyl phthalate, (R) E,Z-nepetalactone, (S) eucalyptol, (T) eugenol, (U) γ-terpinene, (V) geraniol, (W) germacrene D, (X) trans-pinocarveol acetate, (Y) lacnophylum ester, (Z) lantadene A and B, (a) lantanilic acid, (b) ligustilide, (c) limonene, (d) linalool, (e) matricaria ester, (f) menthol, (g) methyl carvacrol/estragole, (h) methyl eugenol, (i) nimbidiol, (j) nimbin, (k) nimbolinin A, (l) Z,E-nepetalactone, (m) oleanonic acid, (n) p-cymene, (o) phytol, (p) pinocarveol, (q) piperitenone oxide, (r) quercetin, (s) rosmarinic acid, (t) safrole, (u) terpinen-4-ol, (v) thymol, (w) trans-β-ocimene, (x) trans-pinocarveol, (y) ursolic acid, (z) uscharin.

Figure 6

Chemical structures of major metabolites detected in adulticidal plants [73,75,77,78]. (a) 2,6,10,14,18,22-tetracosane hexane, (a1) p-cymene, (b) 2,6,10,15,19,23-hexamethyl tetracosane, (b1) terpinen-4-ol, (c) linalool, (c1) thymol, (d) eugenol, (e) β-pinene, (f) d-limonene, (g) estragole, (h) carvone, (i) α-terpinene, (j) citronellal, (k) β-caryophyllene, (l) citronellol, (m) tetracontane, (n) 1,8-cineole, (o) α-pinene, (p) geraniol, (q) carvacrol, (r) γ-terpinene, (s) neral, (t) geranyl acetate, (u) methyl benzoate, (v) myrcene, (w) octanol, (x) piperitenone, (y) pulegol, (z) sabinene.

Figure 7

Chemical structures of major metabolites detected in pupicidal plants [73,75,77]. (a) 2,6,10,14,18,22-tetracosane hexane, (a1) trans-anethole, (b) 2,6,10,15,19,23-hexamethyl tetracosane, (c) linalool, (d) carvone, (e) β-pinene, (f) d-limonene, (g) estragole, (h) niloticin, (i) carvacrol, (j) citronellal, (k) p-cymene, (l) citronellol, (m) tetracontane, (n) 1,8-cineole, (o) α-pinene, (p) geraniol, (q) thymol, (r) trans-β-ocimene, (s) neral, (t) geranyl acetate, (u) methyl benzoate, (v) myrcene, (w) octanol, (x) piperitenone, (y) pulegol, (z) sabinene.

Figure 8

Chemical structures of major metabolites detected in plants displaying ovicidal and oviposition deterrence activities [75,76,77]. (a) (6RS)-6,19-epidioxy-24,24 difluoro-25-hydroxy-6,19-dihydroxyvitamin D3 (6RS)- 6,19-epidioxy-24,24-dif, (b) niloticin, (c) Z-azarone, (d) 1-dodecanoyl-2-octadecanoyl-glycero-3-phospho-(1′-sn-glycerol), (e) 3-n-decyl-acrylic acid, (f) 8-hydroxy mianserin, (g) α-copaene, (h) arginine, (i) C16 sphinganine, (j) cosmosiin, (k) δ-elemene, (l) fentanyl, (m) fipexide, (n) mytiloxanthin, (o) patchouli alcohol, (p) phytosphingosine, (q) serine, (r) valine.