DPPH Free Radical Scavenging Activity of Citrus aurantifolia Swingle Peel Extracts and their Impact in Inhibiting the Browning of Musa Paradisiaca L. Var. Kepok Tanjung Explants
Unknown authors
Abstract
Musa paradisiaca var.Kepok Tanjung is a popular banana cultivar that is widely consumed by the majority of the Indonesia's population.However, the browning of explants caused by the polyphenol oxidase (PPO) enzyme is becoming a major constraint for its production which can lead to the low productivity of seedlings.Therefore, this research aims to determine the antioxidant activity of Citrus aurantifolia peel extracts and their ability in inhibiting the browning of Kepok Tanjung bananas explants at the shoot initiation stage under in vitro condition.The extracts were obtained through the maceration of C. aurantifolia peel residue using n-hexane, ethyl acetate, and ethanol solvents which were added to the culture medium.Furthermore, the 50% inhibitory concentration (IC50) was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, while enzyme activity was assessed by spectrophotometric method using catechol substrate.The results showed that the ethyl acetate extract of C. aurantifolia peel from day 6 at concentration of 0.3 mg/mL can inhibit oxidation, as shown by the reduced browning index of the explants.Meanwhile, the highest antioxidant activity was discovered at day 9 with PPO enzyme activity of 80.261 U/mL at the same concentration.