ANTIOXIDANT AND TYROSINASE INHIBITOR ACTIVITIES OF MANALAGI APPLE (MALUS SYLVESTRIS (L.) MILL) ETHANOLIC EXTRACT AND SELECTED FRACTION

• Main Author: Athaayaa Nurman, Chelzsya
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/80271
• Institution: Institut Teknologi Bandung

Free radicals are reactive compounds with unpaired electrons in the outer orbital that can cause damage to cell components, increasing the risk of disease. Antioxidants can protect cells from damage by inhibiting free radical attacks. Melanogenesis, catalyzed by the tyrosinase enzyme, also plays a role in protecting the skin with melanin's ability to absorb UV rays. This research outputs are the antioxidant and inhibitory activity of the tyrosinase enzyme from extracts of flesh, peel, and leaves of Manalagi apples (Malus sylvestris (L.) Mill), determination of the fraction with the best activity, total phenolic content, total flavonoid content, and identification as well as quantification of several phenol and flavonoid compounds. Extraction was carried out with the Ultrasonic-Assisted Extraction method using 96% ethanol, while fractionation was carried out with the liquid-liquid extraction method using n-hexane, ethyl acetate, and water-ethanol. The 2,2-Diphenyl-1- picrylhydrazyl (DPPH) antioxidant activity and tyrosinase inhibitors were determined using a microplate reader and total phenol and flavonoid levels were determined using UV-Vis spectrophotometry. Identification and quantification of phenol and flavonoid compounds in extracts and fractions were carried out using thin layer chromatography and high-performance liquid chromatography. The highest levels of phenols and flavonoids were contained in the leaf extract, which were 15.395 g GAE / 100 g and 7.825 g QE / 100 g. Apple peel extract showed very strong antioxidant activity (IC50 37.133 µg/mL). The ethyl acetate fraction of the peel showed increased antioxidant activity (IC50 16.700 µg/mL). The extract of the three apple parts shows low tyrosinase inhibitor activity (IC50 > 1000 µg/mL). Phenolic compounds contribute to both activities. The fruit peel extract contains catechin (0.079%), while the ethyl acetate fraction of the peel contains catechin (0.702%) and chlorogenic acid (2.310%). Overall, ethanolic extract and ethyl acetate fraction of the peel show potential antioxidant activity in vitro which needs further investigations in vivo.