Larvicidal activity and chemical compositions of Aloe ferox mill, and Commipora abyssinica (O.Berg) combination against the mosquito vectors Culex pipiens L

The aqueous extract was prepared from the Aloe ferox, and Commipora abyssinica combined to develop a botanical mosquito larvicide. The aqueous extract and the solvent fractions obtained using liquid-liquid extraction were tested against Culex pipiens larvae for larvicidal potential. The maximum larvicidal activity was recorded for the ethyl acetate (EtOAc) extract with LC50 values of 28.24 mu g/mL followed by hexane (104.42 mu g/mL), water (140.24 mu g/mL), and chloroform (211.41 mu g/mL) extract against the Cx. pipiens third instar 24 h post-treatment. In midguts of EtOAc extract-treated larvae, Longitudinal sections showed edema between the degenerated epithelial cells and degraded microvilli. The extract caused a dose dependent decrease in the percentage of cell viability of HUVEC cells suing MTT (3-[4,5-dimethylthia zol-2-yl]-2,5-diphenyltetrazolium bromide) assay. The IC50 value of the EtOAc extract was 143.6 mu g/mL and displayed chromosomal condensation. The total phenolic and flavonoid contents calculated were 15.9 GAE/g (gallic acid equivalent per gram) and 3.69 QurE/g (Qurcetin equivalent per gram), respectively. GC-MS analysis showed that the major chemical components of the EtOAc extract were methyl ester of hexadecanoic acid (28%), 3-benzylbutanoate (9.4%), methyl ester of octadecanoic acid (8.6%), and alpha-muurolene (5.3%). The current investigations revealed the possible use of this botanical combination as a larvicide against Cx. pipiens larvae. (c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

The aqueous extract of Aloe ferox and Commipora abyssinica has the potential to develop a botanical mosquito larvicide. The ethyl acetate extract shows the highest larvicidal activity and causes cell degeneration and decreased cell viability. Chemical analysis reveals the major components of the extract, and the total phenolic and flavonoid contents are quantified.