Zhu Ling (P. umbellatus) mushroom contains a comound which may promote hair regrowth. - GreenMedInfo Summary
Studies on active substances in herbs used for hair treatment. I. Effects of herb extracts on hair growth and isolation of an active substance from Polyporus umbellatus F.
Chem Pharm Bull (Tokyo). 1994 Mar;42(3):530-3. PMID: 8004697
The effects of methanol extracts of 80 herbs on hair growth were investigated, using normal C3H/He mice from which telogen hair on the back had been removed. Eighteen of the extracts apparently promoted hair regrowth on the mice. As one of active principles in Polyporus umbellatus F., 3,4-dihydroxybenzaldehyde was isolated by column chromatography on Amberlite XAD-2, Sephadex LH-20 and silica gel.