Supercritical CO2 extraction of oleoresin from black pepper (piper nigrum) and antioxidant activity of the oleoresin
Abstract
The supercritical fluid extraction (SFE) method was used to extract oleoresin from ground
black pepper (Piper nigrum), using carbon dioxide fluid as main solvent. The raw material was tested to determine the moisture content, volatile oil, total ash, crude fiber and bulk density with resulted 11.6%, 2.6%, 3.8%, 11.33% and 545 g/L respectively. The process parameters, namely pressure P (200, 250,300 bar), temperature T (35, 45, 550c), and
extraction duration t (90, 120, 150 minutes), were investigated in a matrix of experiments
in order to find out their effect to the extraction processes. A Response Surface
Methodology with the 3-parameters central composite orthogonal design (CCOD) was used
for process optimization. As a result, a quadratic model was determined for a dependence of the extraction yield on 3 parameters. The result from ANOVA showed that the model adequately represent the experimental data. The optimized parameters, determined by
solving the model, were as P= 266 bars, T= 47oC and t = 150 min, with the predicted extraction yield of 5.33%. The yield of piperine in the extracts was determined by a
Spectrophotometric method. The antioxidant properties determination was done by
screening its free radical scavenging activity, with ascorbic acid as a reference sample and using 1, 1-diphenyl-2-pircryl-hydrayl (DPPH) as a free radical agent. The piperine content was in the extracted oleoresin varied from 25.74% to 48.32%.
Key words: Supercritical fluid extraction, black pepper, oleoresin, piperine, CCOD, optimization, antioxidant properties, DPPH, Spectrophotometry