Production of biopesticide from Melia azedarach Linn extract obtained by supercritical fluid extraction for the control of Tetranychus urticae

Compounds derived from plant extracts, such as those from the fruits and leaves of Melia azedarach Linn (chinaberry tree), which contain azadirachtin, have been utilized for crop pest control. However, these natural compounds are susceptible to degradation during extraction and in field conditions. To address this, extraction processes involving supercritical fluid and microencapsulation via spray drying may be employed to obtain and preserve biopesticidal molecules. This study focuses on producing a biopesticide from M. azedarach L. fruit extract using supercritical CO2, and microencapsulation via spray drying with a blend of cheese whey and gum Arabic. The extract was obtained from chinaberry fruits rich in azadirachtin (736.92 μg/L) using supercritical CO2 at 250 bar and 50 °C for 120 min, with a yield of 3.44%. The extract was then encapsulated using cheese whey and gum Arabic (70:30) as encapsulating agents at extract:encapsulating agents ratios of 1:10 and 1:15. Mortality rates of Tetranychus urticae Koch adult females and their eggs, in contact and residual assays with both non-encapsulated and encapsulated extract, did not significantly differ (p > 0.05) from the commercial acaricide abamectin. This study introduces a potential new biopesticide that utilizes chinaberry extract obtained through supercritical CO2 extraction and encapsulation for industrial scale-up studies, and this approach holds promise for the production of an effective biopesticide for crops affected by two-spotted spider mites.