Purification, Phenolic Profile and In vitro Antioxidant Activity of Bioactive Compounds in Milk Thistle Seed (Silybum Marianum)

Abstract

Milk Thistle (Silybum marianum L.) seed extract possesses bioactive compounds. The study aimed to investigate the influence on time, temperature, solvent, and solid ratio as optimal conditions for the efficiency of extraction of polyphenol, flavonoids, and antioxidant properties obtained from milk thistle seeds. The optimized conditions model (time (60min), temperature (70 °C), solvent (80 %), and solid ratio (1:10)) showed a better correlation between the prophesied and experimental values. Overall, the results revealed that the purification of flavonolignans was optimized by dynamic state (2BV) with the most favorable state AB-8 for the separation of impurities and high contents of polyphenols. Silymarin (SMR) is the basic compound with a molecular weight is 481 m/z in milk thistle, identified by optimized HPLC condition and characterized by ESI-MS/MS; active fractions were isolated by ÄKTA purifier with 40% methanol. Furthermore, each compound had good antioxidant activity on RAW 264.7 cells. %DPPH activity is much higher in SMR rather than components; hence, TXF is the most effective compound of SMR as free radical and hydroxyl radical antioxidant activity, SCN and SDN also showed effect as a total antioxidant activity rather than SBN and ISBN.