The Effect of Type and Concentration of Carrier Agent on Antioxidant Capacity and Physical Properties of Gotu Kola (Centella asiatica) Leaf Extract Microcapsule

Abstract

Centella asiatica has been used for medicine, pharmaceuticals, and food supplementation, owing to its high phenolic and flavonoid content, as well as its significant antioxidant activity in the leaves. The need to transform its extract into powder form using microencapsulation is currently emerging, enabling convenience and versatility for various food industrial applications. Spray drying is the most used method of microencapsulation that provides high-quality microencapsulates and better retention of bioactive compounds by entrapping them in a carrier agent material. Spray drying conditions undoubtedly determine the physical and antioxidant qualities contained in the resulting powders. Thus, this study examined how gum arabic (GA) or resistant maltodextrin (RM) at different ratios of extract to carrier agent (1:1 and 1:2) affect the physical and antioxidant characteristics of C. asiatica extract (CAE) microcapsules. Physical properties were observed through parameters such as encapsulation yield, moisture content (MC), water activity (Aw), color, and solubility, while total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity by DPPH and FRAP assay were done to determine the antioxidant properties. The results showed that CAE:GA (1:1) had significantly higher values for all antioxidant analyses, CAE:RM (1:1) was higher in yield, CAE:RM (1:2) was lower in MC and Aw, and lighter in color (p≤0.05). Future studies are suggested to use an industry-scale spray dryer and combine the usage of both carrier agents to improve the findings from the current study.