AKTIVITAS ANTIOKSIDAN EKSTRAK DAUN DAN BUAH JAMBU BIJI KRISTAL (PSIDIUM GUAJAVA L.’KRISTAL’) DENGAN METODE DPPH, CUPRAC DAN FRAP

• Main Author: Izzati Nadifan, Hashifah
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/48649
• Institution: Institut Teknologi Bandung

Free radicals can cause many diseases, such as cancer. Antioxidant is compound that could scavenge free radical activity. One of natural antioxidant such as guava. The objectives of this research were to investigate antioxidant activity of leaves and fruits of crystal guava through determine the value of Antioxidant Activity Index (AAI) using DPPH, CUPRAC and FRAP; determine total phenolic content (TPC) and total flavonoid content (TFC); analyze correlation between TPC and TFC with AAI DPPH, CUPRAC and FRAP, and analyze correlation between 3 methods. Extraction was performed by reflux method using n-hexane, ethyl acetate, and ethanol. Determination of AAI DPPH, CUPRAC, FRAP, TPC and TFC were performed by UV-visible spectrophotometry. Correlation of TPC, TFC with AAI DPPH, CUPRAC and FRAP, and also correlation of 3 methods by Pearson’s method. Antioxidant activity of leaves and fruits extracts of crystal guava showed AAI DPPH in the range of 0.33-56.46, CUPRAC 0.20-7.31 and FRAP 1.65-59.89. The highest TPC was given by ethanol leaves extracts (49.55 ± 1.45 g GAE/100 g), while the highest TFC for n-hexane leaves extract (9.68 ± 0.210 g QE/100 g). TPC of leaves extract had significantly positive correlation with AAI DPPH, CUPRAC and FRAP. AAI DPPH, AAI CUPRAC and AAI FRAP of leaves and fruits extract of crystal guava showed significantly positive correlation. In general, ethyl acetate and ethanol leaves extracts had strong to very strong antioxidant activity by three methods. TPC in leaves extract contributed to antioxidant activity by DPPH, CUPRAC and FRAP methods. Antioxidant activity of leaves and fruits extracts of crystal guava were linear by three methods.