Extraction of tannic acid from macassar kernels (Brucea Javanica) by ultrasonic-assisted extraction

Abstract

In this study, the tannic acid compound from Brucea javanica sp was extracted by conventional and non-conventional methods, which are maceration and ultrasonic-assisted extraction (UAE). Tannic acids are based on flavonoid compounds with antimicrobial properties commonly used as astringent to avoid irritation on the skin. In a conventional extraction, there are two parameters studied namely; extraction time (4, 6, and 8 hours) and temperature (30°C, 40°C, 50°C, and 60°C). From the obtained results of conventional extraction, the optimum yield of tannic acid was found at 6 hours of extraction time with a temperature of 50°C at 0.1527 mg/mL. The ultrasonic-assisted extraction is a green technology, which is expected to extract tannic acid in a shorter time and has high extract yield and eco-friendly extraction technologies. The two parameters studied are sonication time (15, 30, and 45 minutes) and duty cycle (25, 50, and 75 %). The constant condition is the ratio of solid to liquid (1:20). For the extraction of tannic acid using the ultrasonic-assisted extraction (UAE) method, the optimum conditions obtained are 30 minutes of sonication time and 25% of the duty cycle. Based on HPLC analysis, the concentration for tannic acid extract using a 25% duty cycle at 30 minutes of sonication time was 0.2313 mg/ml. The band spectrum for FTIR analysis in the pure and extracted samples showed a similar pattern represented by the functional group of anhydride and carbonyl stretching vibration. Scanning Electron Microscopy (SEM) imaging showed that the ultrasonic-assisted extraction (UAE) method better ruptured the cell and created more pores to increase the penetration of solvent and thus the yield of extraction of ultrasonic-assisted extraction (UAE) method was higher than conventional extraction method. From the findings, it is proven that UAE is a significant method for tannic acid extraction from Brucea javanica sp.