Evaluation of phenolic constituents and antioxidant activity of different Mango peel varieties and optimization studies employing ultrasound Assisted Solvent Extraction (UAE) method

Abstract

Phenolic compounds are classified as the basic phenols or polyphenols that based on number of phenol units in the molecule. It is secondary metabolite that has ability to prevent oxidative in food and categorized as natural antioxidant. Mango peels is one of the waste by product that were not utilized but it have a lot of valuable bioactive compound. In this study the dried mango peels was used for the extraction of phenolic content by employing Ultrasound Assisted Extraction (UAE) method. The five various types of mango peels were used in the extraction of phenolic. The parameters were liquid to solid ratio, extraction time and extraction temperature. The screening process was used to determine the higher total phenolic content and antioxidant capacity in conditions of 40 ml:1g, 30 minutes and 50 ºC and Pipi Merah mango cultivar had been found as the best total phenolic content in obtaining high yield of phenolic. The Pipi Merah is used in the further analysis as it has the highest phenolic content among five types of mango cultivar. The optimization study was carried out using Response Surface Methodology (RSM). Based on the result obtained, the optimized conditions were 40.22 ml/g liquid to solid ratio, 28.85 minutes extraction time and 44.05 ºC extraction temperature with the maximum yield of total phenolic content of 300.272 mg GAE/g. A validation step was conducted and yields of 291.5 ± 2.92 mg GAE/g phenolic content was obtained with same condition. FTIR was used to characterize the functional group that related to bioactive compound in mango peels. The percentage yield extraction of the Pipi Merah mango peels extract was 46.76%.