Effect of Supercritical CO2 and Microwave -assisted Extraction Methods on Bioactive Compounds Extraction from Silybum marianum Seed.

In the current study, the effect of different new extraction methods including supercritical carbon dioxide extraction (SC -CO2), microwave - assisted extraction (MAE), and also conventional Soxhlet extraction (CSE) were investigated on bioactive compounds recovery from Silybum marianum seed. The crude extraction yield (22.40± 0.15%) was obtained using CSE, while the efficiency of SC -CO2 and MAE were about 89 and 50% of those obtained using CSE. The highest free radical scavenging activity in terms of DPPH and HO radicals was obtained in an extract obtained using SC -CO2. From the TPC analysis, the highest and lowest value was determined in extracts obtained using SC -CO2 (102.93± 0.14 mg GAE/g) and CSE (14.50± 0.18 mg GAE/g), respectively. Fatty acid composition was analyzed using Gas Chromatography –Mass Spectrometry. Linoleic and oleic acids were determined as the main fatty acids. Finally, it can be concluded that S. marianum seed is a potential source of bioactive compounds and new extraction techniques of SC - CO2 and MAE could be suggested as promising methods to substitute conventional method for successful recovery of bioactive compounds. [ABSTRACT FROM AUTHOR]