Enzyme-assisted ultrasonic extraction of chlorogenic acid from Solanum lasiocarpum Dunal (terung asam) fruit: Extraction kinetics and pancreatic lipase inhibitory activity

Chlorogenic acid (CGA) is a bioactive phenolic compound with recognised antioxidant and anti-obesity potential. However, efficient recovery from underutilised tropical fruits such as Solanum lasiocarpum Dunal remains constrained by extraction inefficiency and compound instability. This study optimised enzyme-assisted ultrasonic extraction for CGA recovery from S. lasiocarpum fruit extract (SLFE), evaluated extraction kinetics using multiple mathematical models, and assessed anti-obesity potential. Pectinase pretreatment at 1% (w/w) for 2 h at 37 °C, followed by ultrasonic extraction, was optimised using a one-factor-at-a-time approach. Extraction kinetics at 40 °C, 50 °C, and 60 °C were analysed using first-order, second-order, Peleg, Elovich, and two-site bioexponential models. Anti-obesity activity was evaluated through pancreatic lipase inhibition. The optimal extraction conditions were a 1:20 solid-to-solvent ratio, extraction temperature of 50 °C, and extraction time of 15 min, producing high crude yield, phenolic and flavonoid contents, and CGA recovery. Among the evaluated models, the two-site bioexponential model provided the best fit, with high coefficient of determination and low error values, indicating biphasic extraction behaviour involving a rapid washing stage followed by diffusion-controlled release. The optimised SLFE demonstrated strong pancreatic lipase inhibitory activity, with potency comparable to pure CGA but lower than orlistat. Extraction temperature played a critical role in governing mass transfer efficiency, with moderate temperature providing an optimal balance between extraction rate and compound stability. These findings highlight SLFE as a promising natural source of pancreatic lipase inhibitors with potential application in obesity management.