Crenulatin
Crenulatin is a gallotannin that can be isolated from Rhodiola rosea. Crenulatin can be used as a biomarker to identify potentially adulterated R. rosea products. Crenulatin has dual- direction effects on apoptosis of cerebral microvascular endothelial cells, via regulating Fas/Bcl-2 expression and caspase-3 activity[1][2][3].