Utilization of triethylammonium hydrogen sulphate-mediated solvent for optimization of asiaticoside extraction and antioxidant capacity of Centella asiatica (L.)

Asiaticoside, a pentacyclic triterpene of Centella asiatica with broad pharmacological actions. Higher asiaticoside content of Centella extracts in food products increases their nutritional and medicinal values. Protic ionic liquids (PIL) were utilized as bioactive extraction additives. The research focuses on obtaining the optimum extraction parameters for higher asiaticoside yield, and Centella extract antioxidant capacity. Optimization of all responses (asiaticoside yield, TPC, TEAC) achieved through faced-centered composite design (FCCD) involving three factors (temperature, extraction time, and triethylammonium hydrogen sulfate, [TEA][HSO4] %). The optimal conditions were 66 °C, 12 h duration, and 20% [TEA][HSO4], which resulted in 4.44 ± 0.05% (w/w) asiaticoside, TPC of 114.11 ± 12.58 mg GAE /g and TEAC of 70.01 ± 5.74 µmol TE/g respectively. All responses fit the quadratic model with proximity between predicted and experimented values. Procurement of higher asiaticoside yield, TPC, and TEAC verified the pertinent of the optimal conditions. In addition, the outcomes give an overview of PILs potential for higher bioactive extractions. Research expansion by utilizing other PILs for plant extraction in addition to solute–solvent interaction study will be beneficial for the designation of an efficient plant extraction process that maximizes the plant-based product market.