Quantitative Determination of Genkwanin in Flos Genkwa by TLC-densitometry Chemical constituents from flower buds of Daphne genkwa Chemical constituents from Dracocephalum heterophyllum Chemical constituents of Premna serratifolia Chemical constituents of Premna serratifolia Inhibitory effect of different species of hydroxygenkwanin on UGTs and UGT1A1 activities Determination of Hydroxygenkwanin and Genkwanin in Flos Genkwa before and after Processing by TLC-scanner HPLC Analysis on Influence of Processing on Contents of Genkwanin in Flos Genkwa Influence of Processing on Contents of Genkwauin in Flos Genkwa HPLC Analysis of Mimic Vinegar processing of Genkwanin Determination of Genkwanin in Flos Genkwa by HPLC Chemical constituents from leaves of wild Aquilaria sinensis Chemical constituents from root tubers of Fagopyrum dibotrys