Selection of Optimum Process, Solvent and Drying Method for Extraction of Antioxidants

An experimental study was performed for optimum process, solvent and drying method for the extraction of antioxidants from Morinda citrifolia fruit. Extractions were performed by soxhlet, ultrasonic and modified version of high hydrostatic pressure extraction at 100 bar and 50°C with 15 grams of powdered morinda in 200 ml of solvent. Water, ethanol and ethyl acetate were used as solvents. The filtrate was dried by vacuum and spray dryers. The antioxidant activity or inhibiton percentage of the extracts was determined by Di-Phenyl picryl hydrazyl radical scavenging method. The yield was also determined. Optimization was performed using response surface methodology. It was found that the highest antioxidant activity or inhibition percentage of DPPH free radicals was exhibited by the extract obtained from HHPE process with ethyl acetate as solvent and vacuum dried. It was also found that the highest yield was obtained from HHPE process at 100 bar and 50°C with ethanol as solvent and vacuum dried. It was noted that the nature of the process and the solvent used significantly contributed to the extraction of antioxidants from Morinda citrifolia fruit when compared with the drying methods