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Silybin and silymarin – short introduction

Silybin (1, Scheme 1) is a flavonolignan contained among other components in the silymarin mixture, extracted from the seeds of milk thistle (Silybum marianum – Figure 1). Silymarin also contains its congeners, e.g., isosilybin, silychristin, silydianin, 2,3-dehydrosilybin, and taxifolin and ca 30 % of an undefined polymeric phenolic fraction (Scheme 2) [].

Scheme 1. Silybin diastereoisomers

Silybin A and Silybin B

Figure 1. (L.) Gaertn.

The has been recognized since ancient times for the treatment of various liver and gastrointestinal diseases including those associated with alcohol abuse and environmental toxin exposure []. These effects are directly related to its well known antioxidant (radical scavenging) activities [1,3]; we have recently described the [].

Other beneficial effects of silybin/silymarin include as well as hypocholestero­lemic, cardioprotective, and neuroprotective effects [,8]. For example, silybin is in in the US for the treatment of prostate adenocarcinoma []. Silybin activities are linked to numerous effects at the cellular and molecular level, such as , modulation of drug transporters (P-glycoprotein) [], and a specific action on DNA-expression via the (NF-κB) [].

Scheme 2. Silybin congeners contained in silymarin

Silybin congeners contained in silymarin


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Institute of Microbiology - Czech Academy of Sciences