Lignans

Seeds, woods and roots are the classic sources:

Plant lignans are largely inactive as eaten. Gut bacteria convert them to the enterolignans — enterodiol and enterolactone — and these are the compounds with weak estrogenic and antiestrogenic activity that flaxseed's phytoestrogen reputation actually rests on.

As with the isoflavones, this makes the response microbiome-dependent: antibiotic use and individual bacterial composition materially change how much enterolactone a given flaxseed intake produces.

Silymarin, and particularly silybin, is the most-used hepatoprotective preparation in the world and the standard of care for Amanita mushroom poisoning in several countries — it competitively blocks the toxin's uptake into hepatocytes.

The schisandra lignans are the actives behind that herb's adaptogenic and liver-supportive profile, and are potent CYP3A4 modulators. Magnolol and honokiol are GABA-A positive modulators with anxiolytic activity. Podophyllotoxin is the semi-synthetic precursor of etoposide and teniposide.