Optimization of Bioactive Compound Extraction from Rose Myrtle Fruit (Rhodomyrtus tomentosa, (W.Ait), Myrtaceae) as the Antioxidant Source

Rose myrtle fruit (Rhodomyrtus tomentosa, (W.Ait), Myrtaceae) is one of fruits widely found in Kalimantan. This fruit contains a bioactive compound that has a potential to be used as medicine. The aim of this study was to obtain optimal temperature and time of extraction in maintaining and protecting the bioactive compound in rose myrtle fruit extract by using water as solvent. This research applied the response surface method with central composite design for two factors, namely, X1 (temperature/°C) consisting of three levels: 70, 80, and 90°C and X2 (time/minute) which consisted of three levels of 60, 90, and 120 minutes. Research parameters included total phenol and antioxidant activity. Moreover, GC-MS was used for the characterization of the chemical compound component contained in rose myrtle fruit extract. Optimization of extraction condition resulted in an optimum temperature for extraction of 80.43°C and optimum time for extraction of 85 minutes with an optimum yield of total phenol of 73.77 mg/100 g fresh fruit and antioxidant activity of 1.0385 µg/ml with desirability of 0.892 or 89.2%.