Fig 1.
The figure depicts the research structure.
The preparation of tobacco leaf extracts (TEs) and cigarette butt extracts (CBs) involves drying tobacco leaves and unsmoked tobacco cigarette butts, then extracting them using methanol and aqueous solvents. The crude extracts were evaluated against Culex pipiens and Aedes aegypti mosquito larvae for their larvicidal activity after 24 and 48 h of exposure to different concentrations of each TE and CB and effects on oviposition by adult females. The metabolic components of the TEs and CBs were identified and characterized using Fourier transform infrared spectroscopy (FTIR), and by screening for the presence of different types of secondary metabolites, determination of total phenolics and total flavonoids, and identification of metabolites by gas chromatography-mass spectrometry (GC-MS). The extracts were also tested for killing mosquito larvae and against non-target organisms to determine their efficacy in the field.
Fig 2.
Tobacco plant, Nicotiana tabacum (St. Catherine, South Sina, Egypt).
Table 1.
Weight of cigarettes, tobacco, filters, and leftover tobacco in various cigarettes and butts.
Fig 3.
Cigarette components with possible lengths of cigarette butts containing tobacco residue.
Fig 4.
Cigarette butt extract concentrations to perform oviposition tests.
Table 2.
Efficacy of Nicotiana tabacum methanol leaf extracts against Culex pipiens and Aedes aegypti 24 and 48 h post-treatment.
Table 3.
Lethal concentrations (ppm) of Nicotiana tabacum methanol and aqueous leaf extracts against Culex pipiens and Aedes aegypti, 24 and 48 h post-treatment.
Fig 5.
The mean number of larval mortalities induced by Nicotiana tabacum leaves (a) and cigarette but extracts (b) against 3rd larval instars of Culex pipiens and Aedes aegypti, 48 h post-treatment.
Table 4.
Efficacy of cigarette butt methanol extracts against Culex pipiens and Aedes aegypti 24 and 48 h post-treatment.
Table 5.
Lethal concentrations (ppm) of cigarette butt methanol extracts against Culex pipiens and Aedes aegypti, 24 and 48 h post-treatment.
Table 6.
Efficacy of cigarette butt aqueous extracts against Culex pipiens and Aedes aegypti 24 and 48 h post-treatment.
Table 7.
Lethal concentrations (ppm) of cigarette butt aqueous extracts against Culex pipiens and Aedes aegypti, 24 and 48 h post-treatment.
Table 8.
Efficacy of cigarette butt extract concentration on oviposition rates of female Culex pipiens.
Fig 6.
Impact of cigarette butt cup colors on female oviposition.
Fig 7.
Impact of Nicotiana tabacum leaves (a) and Merit cigarette butt (b) methanol extracts against non-target predators.
Fig 8.
Field evaluation for larvicidal efficacy of Nicotiana tabacum leaves (a) and Merit CB (b) methanol extracts treated at a dose of LC95 X2 (194.2 and 30.9 ppm) in mosquito larval pools.
Fig 9.
Absorption of tobacco leaves (a) and Merit (b) cigarette but methanol extracts as function of wavelengths.
Fig 10.
FTIR plot of tobacco leaves (a) and Merit (b) cigarette butt methanol extract.
Table 10.
The major chemical constituents in Nicotiana tabacum aqueous extracts.
Table 11.
The major chemical constituents in Merit cigarette butt methanol extracts.
Table 9.
The major chemical constituents in Nicotiana tabacum methanol extracts.