Enhancing the stability of Centella asiatica bioactive compounds via ultrasound-assisted extraction and microencapsulation via ionotropic gelation

extract using the ion-gel method, capable of protecting and preserving the bioactive compounds. The research results showed that the extraction process achieved the highest efficiency when using 80% ethanol, with a material:solvent ratio of 1:80, and sonication at 50 °C for 45 min. Under these conditions, the extracts obtained had total polyphenol (TPC) and total flavonoid (TFC) content of 379.537 ± 1.223 mg GAE/g DW and 154.258 ± 0.467 mg QE/g DW, respectively, demonstrating that the ultrasonic method contributed to increasing the ability to break down plant tissue and release active ingredients effectively. In the microencapsulation process, the gel formation conditions using 2% alginate, with an ultrasonic vibration amplitude of 50% for 5 min, resulted in a uniform microencapsulation system with a microencapsulation efficiency of 83.84%, stable particle structure, and suitable hardness and swelling. After 1 month of storage, the microencapsulation system maintained good quality, demonstrating the effective protection and stabilization of active ingredients by the alginate material.