EFFECT OF EXTRACTION METHOD ON THE RECOVERY EFFICIENCY OF POLYPHENOL COMPOUNDS FROM Muntingia calabura L. LEAVES

This research presents the results of recovering polyphenolic compounds from the waste and by-product material of Muntingia calabura L. leaves using extraction methods like maceration, ultrasound-assisted extraction, and ultrasound-assisted enzymatic extraction. In the maceration method, several factors were studied: solvent type (ethanol, methanol, water); solid-liquid ratios (1:5, 1:10, 1:20, 1:30, 1:40); and extraction times (3; 5; 7; 9; 11 hours). This method achieved a total polyphenol content of 32.24 mgGAE/g. Using ultrasound-assisted extraction, the following factors were examined: ultrasound power (100; 200; 300 W); solid-liquid ratios (1:5, 1:10, 1:20, 1:30, 1:40); and times (3; 5; 10; 30; 50 minutes). This method yielded a total polyphenol content of 38.265 mgGAE/g. Additionally, response surface methodology with a central composite design (RSM-BBD) was applied to optimize the polyphenol extraction process from M. calabura leaves. The model was designed with 15 experiments, including 3 central points, using ultrasound-assisted enzymatic extraction with 3 factors: enzyme concentration (0.5; 1; 2; 2.5; 3%), pH activation (4, 5, 6), and temperature activation (30, 40, 50, 60, 70°C). The ANOVA analysis results showed a high value of R² and p < 0,0001 indicating the model's statistical significance, leading to a total polyphenol content of 74,0125 mgGAE/g. The FTIR spectrum of the M. calabura leaf extracts indicated the presence of functional groups characteristic of polyphenolic compounds, including aromatic alcohols (-OH), alkenes (-CH), esters (-C=O), amino acids (C=C), and alcohols and ethers (C-C).