Competition bioassay method

Leverrier et al. had carried out activity-guided fractionation of the E. kingiana Gamble extract by means of an established competition bioassay method. " They then used this assay to measure the inhibition of the binding of the fluo-rescently labeled BH3 domain of Bak to Bcl-xL by each of the kingianins. Leverrier et al. noted that the kingianins with two acidic side chains were more active in the in vitro assay than those with only one acidic side chain and that those with no acid side chain were least active. They reported Ki values of 2 to >300 pM for the racemic compounds. 

Other methods applied to the measurement of prostanoids include gas chromatography with electron capture detection (19-21), bioassay (22), competitive receptor binding assays (23) and radioimmunoassays (2 ). It is important to check these assays against GC/MS which is considered the reference method. 

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