Characteristics and Antioxidant Activities of Three ‘Beras Kencur’ Effervescent Formulations

Abstract This study aimed to evaluate the physical characteristics and antioxidant activities of beras kencur effervescent tablet formulations. Beras kencur was prepared in 7 different concentrations to assess the percent inhibition. The highest inhibition potency (76.2%) was found in beras kencur 10 mg/mL. This concentration was used to obtain the formulation of the effervescent tablet, which differed in definite proportions of citric acid (C 6 H 8 O 7 ), tartaric acid (C 4 H 6 O 6 ), and sodium bicarbonate (NaHCO 3 ). When dispersed in water, the tablet produces a bubbling reaction by releasing CO 2 . The tablets were evaluated for pH, soluble time, total phenolic content (TPC), and antioxidant activity. These observations demonstrated that the higher proportion of NaHCO 3 led to the higher solubility of the effervescent tablet. The antioxidant activity of formulations was evaluated using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and total phenolic content was determined using Folin-Ciocalteau. The outcomes suggested that the phenolics might become unstable at high acid conditions. In contrast, an increase in alkaline pH increased the ability of effervescent tablets to produce reactive oxygen species (ROS). The tablet with an equal proportion of acid and base showed the highest antioxidant activity (IC 50 = 20.8), in line with the total phenolic content (5.772 mg GAE/mL).