Figure 3
Chemotaxis-based chemical analysis of M. alba . (A) Flow chart of the bioactivity-directed fractionation and isolation (BDFI) analysis. A M. alba branch was ground and extracted with methanol (MeOH). The crude extract (CE) was tested for bioactivity using chemotaxis assay. The same crude extract was sequentially partitioned with ethyl acetate (EA), butanol (BuOH and water (H2O). The bioactivity of the 3 fractions was further tested. Finally, active compound, oxyresveratrol, was purified from the active EA fraction. The dry weights of the crude extract, fractions and compound of M. alba are indicated as percentages of the dry weight of the raw plant material. (B) HPLC profiles of methanol crude extract (CE), ethyl acetate fraction (EA), butanol fraction (BuOH), water fraction (H2O) and oxyresveratrol with UV detection at 254 nm. Peak 1 is identified as oxyresveratrol.