HPLC analysis of resveratrol. E. coli expressing 4CL1 and STS was cultured in modified M9 medium with glycerol, and containing 1 mM 4-coumaric acid, at 30°C for 24 hrs prior to extraction. Upper chromatogram shows extracted E. coli culture and bottom chromatogram shows resveratrol standard run under identical HPLC conditions. At right are the UV spectra for both recombinant resveratrol (1) (m/z 227.1) and resveratrol standard (2) (m/z 227.1). No residual 4-coumaric acid was detected by HPLC or LC-MS.