Extraction of baby java citrus (Citrus sinensis (L) Osbeck) peel by microwave-assisted extraction

Baby java citrus (Citrus sinensis (L) Osbeck) processing produces peel waste which contains phenolic compounds, flavonoids, and tannins. The aims of this research were to study the effect of ethanol concentration and extraction time by Microwave Assisted-Extraction on the bioactive compounds extracted. The research used Factorial Randomized Block Design (FRBD) with two factors which were ethanol concentration (90, 85 and 80%) and extraction time (10, 20, and 30 min). The results showed that ethanol concentration and extraction time and then their interaction had significant differences (p≤0.05) to total phenolic, total flavonoid, total tannin and antioxidant activity (IC₅₀). The best result condition of extraction was ethanol 90% for 30 min, the extract obtained had characteristic as follow: total phenolic of 21.79 mg GAE/g, total flavonoid content 4.11 mg QE/g, total tannin content of 18.83 mg TAE/g and antioxidant activity (IC₅₀) 348.19 ppm.