Botanical insecticide production for mealybug (Dysmicoccus neobrevipes) pest control using pineapple waste mixture through ultrasonic-assisted extraction method by adjusting type of solvents

The pineapple (Ananas comosus (L) Merr.) plant is commonly planted in Indonesia. As the ninth-largest pineapple-producing nation, Indonesia produced 2,886,417 tons of pineapples in 2022. There is a rising trend in this production number from year to year. However, mealybug pests (Dysmicoccus neobrevipes) continue to be a challenge for pineapple growers. Mealybug pest (D. neobrevipes) as a vector could transmit pineapple mealybug wilt-associated virus, potentially reducing the quality of the fruit’s harvest. On the other hand, waste from the production of pineapple, like as peels, crowns, and leaves, is frequently generated. As a result, the extract of the pineapple waste mixture has the potential to be used as an insecticide against mealybug pest (D. neobrevipes). The production of botanical insecticide in this study uses the ultrasonic-assisted extraction method by adjusting the type of extraction solvent with different polarities so as to obtain the optimum bioactive insecticide content. Ultrasonic-assisted extraction uses ultrasonic waves to break down the cell wall, allowing the bioactive components to be extracted. Different solvent polarities will extract different bioactive components, resulting in different insecticidal effects. The results showed that there was no statistically significant difference in mortality results between 25 mg/ml of 80% ethanol and chloroform solvent extracts (61.46% and 34.73%, respectively). However, considerations of safety, efficacy, and yield aspects show that ethanol solvent is better to use in multilevel extraction for the production of botanical insecticides. Petroleum ether extract is not employed in the efficacy test because the yield is too low to be used to the treatment. The efficacy test of varied concentrations of 80% ethanol solvent extract revealed no significant mortality ability at concentrations of 25 mg/ml (61.46%), 50 mg/ml (71.77%), and 75 mg/ml (75.48%). The LCMS analysis revealed that the 80% ethanol extract included chemicals that might be used as insecticides, including (-)-epigallocatechin 3,4’-di-gallate as the highest amount, along with myricetin, gluconapin, 3,8’-biapigenin, diferuloylputrescin, and nimbolinin D, which had the greatest level. Pheophorbide B. was the compound with the highest amount in the chloroform extract, along with nimbolinin D, cucurbitacin B, and (-)-epigallocatechin 3,3’-di-gallate. A mixture of 21 grams of pineapple waste produced extract yields in ethanol and chlorof