Milk Thistle Oil Extracted by Enzyme-Mediated Assisted Solvent Extraction Compared with n-Hexane and Cold-Pressed Extraction

Abstract

Silymarin and milk thistle oil have unique biological benefits; however, applying silymarin to milk thistle oil remains a challenge. In this research, the content of silymarin in milk thistle oil conditions using enzyme-mediated solvent extraction was investigated and optimized by response surface methodology. The optimal extraction conditions using enzyme-mediated solvent extraction were as follows: the enzyme-added content was 3.06 mg/mL, the enzymatic hydrolysis temperature was 55.09 °C, and the enzymatic hydrolysis time was 66.28 min. Oil extracted by the enzyme-mediated assisted solvent was further compared with those extracted with n-hexane and cold pressing. Results indicated that the oil extraction using the enzyme-mediated assisted solvent had a lower acid value (2.20 ± 0.01 mg/g) and the highest α-tocopherol content (0.62 ± 0.00 mg/g), total phenols (7.67 ± 0.01 mg/g), and flavonoids (1.06 ± 0.13 mg/g). Furthermore, the antioxidant capacity of milk thistle oils was further investigated. The results showed that the enzyme-mediated assisted solvent-extracted oil had the strongest antioxidant capacity with lower lipid oxide content. Therefore, enzyme-mediated solvent extraction is an excellent method for extracting milk thistle oil.

Methanol Extracts from Cirsium japonicum DC. var. australe Kitam. and Their Active Components Reduce Intracellular Oxidative Stress in Caenorhabditis elegans

“…Although the solvent was chosen according to previous research [10,11], the residual methanol may pose a health concern in the medical application of the extracts. In future research, there is an opportunity to enhance our processes by drawing on insights from successful studies related to milk thistle or silymarin [41,42], which have demonstrated effective optimization strategies. Additionally, we should note that our study did not examine the biological activity or toxicity of other ingredients; therefore, future studies should evaluate the antioxidant potential of these additional components.…”