EXTRACTION OF NATURAL ANTIOXYDANTS FROM ALGERIAN ROSMARINUS OFFICINALIS L. WITH GRAS-SOLVENT AND KINETIC STUDY

Abstract

The objective of this study was to improve extraction of natural antioxidants (NAs) found in Algeria Rosmarinus officinalis L. using cleaner extraction processes. To verify the single factors effects, a Factorial design (FD) was used to study the impact of the main process variables (time, solid-to-liquid ratio, and temperature) on extraction efficiency. Total Polyphenol Content (TPC), Total Flavonoids Content (TFC) and Antioxidant Activity (AA) were measured to control the extraction process efficiency on different experimental conditions. The best experimental result was obtained at 30°C for 30 min and 0.05 g/mL. The value of TPC, TFC and AA was respectively, 121.80 mg GAE/g DW, 44.01 mg QE/g DW and 96.36 %. The correlation between TPC, TFC and AA remains unclear. The extraction of polyphenols was shown to obey first order kinetic with a 0.045 min^-1coefficient for the fast period and 0.05 min^-1 for the slow period. Finally, the plant morphology investigated by SEM revealed physical changes on plant material.