A medium sized (1-3m tall) shrub with edible, red berries. Pretty much all parts of it (root, bark, leaf and fruit) have been used as folk medicine for a long time to treat everything from heart diseases to anxiety.
As for the root extract and skincare, barberry root contains alkaloids (the most important one is berberine) that have significant antibacterial and anti-inflammatory properties.
There is one more interesting thing: an animal study from 1993 found that berberine can reduce lipogenesis (63% by 10(-4) M berberine) in the sebaceous glands of hamsters. This might be the reason why some traditional Japanese-Chinese herbal medicine with berberine seem to work against acne vulgaris. If you are acne-prone, barberry root extract might be something to try.
- Phytotherapy Research, Aug 1, 2008, Pharmacological and therapeutic effects of Berberis vulgaris and its active constituent, berberine
- Skin Pharmacol. 1993;6(1):56-60., Effect of some alkaloids, flavonoids and triterpenoids, contents of Japanese-Chinese traditional herbal medicines, on the lipogenesis of sebaceous glands.