Inhibitory effects of oil extract of green Acalypha (Acalypha wilkesiana) on antioxidant and neurotransmitter enzymes in Callosobruchus maculatus

Abstract

Background: Callosobruchus maculatus is an important insect pest of cowpea. The inhibitory effects of oil extract of Acalypha wilkesiana (Muell Arg.) leaves on antioxidant, neurotransmitter, and detoxifying enzyme in adult Callosobruchus maculatus (Fabricius) were evaluated under laboratory condition. The leaves of the plant were collected fresh and air-dried before the oil was extracted from them through cold extraction method while ethanol was used as solvent. Adult C. maculatus were exposed to 0.2, 0.4, 0.6, 0.8, and 1.0 ml of 0.5% concentration of the oil extract and were homogenized separately. The supernatants gotten from them were used as enzyme sources. The activities of SOD, CAT, GPx, AChE, CarEST and GST were observed with photospectrometer. GC-MS analysis was done to evaluate the active compounds present in the oil extract. Results: The activities of the enzymes increased at lower dosages of the oil extract (0.2 and 0.4 ml) and reduced drastically at higher dosages of the oil (0.6, 0.8, and 1.0 ml). However, AChE activity was more affected by the oil extract as it was almost inhibited by the oil extract. The GC-MS showed that 114 compounds were present in the oil extract of the plant while acetaldehyde had the highest percentage (46.07%) of the total compounds. Conclusion: Based on these findings, the oil extract of A. wilkesiana could be a good biopesticide for the control of adult C. maculatus instead of synthetic chemical insecticides.

Assessment of Sex-Specific Toxicity and Physiological Responses to Thymol in a Common Bean Pest Acanthoscelides obtectus Say

“…For instance, bean weevil females exposed to thyme essential oil had lower a level of damaged lipids ( Lazarević et al, 2020 ). In consistence with our results, SOD and CAT were elevated by thymol in Ephestia kuehniella larvae ( Shahriari et al, 2018 ), by carvacrol, p-cymene and γ-terpinene in S. littoralis larvae ( Agliassa and Maffei, 2018 ), by carvacrol in Lymantria dispar larvae ( Chen et al, 2021 ), by ethanolic extract of Acalypha wilkesiana leaves in Callosobruchus maculatus adults ( Oni et al, 2019 ) and by Boswellia carterii EO in adults of two Callosobruchus species ( Kiran et al, 2017 ). SOD and CAT responses to botanicals may vary depending on insect species, duration of exposure, botanical type and concentration.…”

“…Several studies have shown that more resistant species had higher SOD and CAT activity, higher induction of activity and/or higher CAT to SOD ratio ( Kiran et al, 2017 ; Petrović et al, 2019 ). Also, in some species, botanicals can reduce SOD and/or CAT activity at high concentrations ( Oni et al, 2019 ; Rajkumar et al, 2019 ).…”

The Effect of Rosmarinus officinalis Essential Oil Fumigation on Biochemical, Behavioral, and Physiological Parameters of Callosobruchus maculatus

“…Moreover, in case of the toxic effects of EOs, the abovementioned enzymes are involved in the defense mechanisms. Depending on the tested EOs, a decrease, increase, or no changes in activity was reported in available studies [ 33 , 34 , 35 , 36 ]. The reduction of activity may indicate the inhibitory activity of the EOs’ components.…”

Mosquito Larvicides of Partial and Combinations Extract of Ethnobotanical Plant from North Sulawesi, Indonesia

“…After the impulse is transmitted the enzyme acetylcholinesterase stops the process, which breaks down acetylcholine into acetyl Co-A and choline. The presence of insecticidal compounds (alkaloids, flavonoids and saponins) will inhibit the work of this enzyme resulting in a buildup of acetylcholine which will cause chaos in the impulse delivery system to muscles and can result in muscle spasms, paralysis and eventually death [35][36][37] .…”