Precarthamin, a yellow precursor of carthamin, was efficiently isolated from the yellow petals of safflower (Carthamus tinctorius L.) with Sephadex LH-20 column chromatography and preparative HPLC, and identified with UV-vis and NMR spectrometry. The UV-vis spectrum of precarthamin showed lambda(max) of 238 and 406 nm in MeOH. The molar extinction coefficients of precarthamin at 406 nm in MeOH and 50 mM citrate buffer (pH 5.0) were 59 000 1/(M∙cm) and 45 400 1.(M∙cm), respectively. The isolated and structurally identified precarthamin was converted to a red pigment by a homogeneously purified enzyme from the immature petals of safflower in 50 mM citrate buffer (pH 5.0). The enzymatically converted red pigment was identified as carthamin, a red pigment of safflower by TLC, HPLC, and UV-vis spectral analysis.
safflower, Carthamus tinctorius, precarthamin, carthamin
NCBI PubMed ID: 10995291Publication DOI: 10.1021/jf9911038Journal NLM ID: 0374755Publisher: American Chemical Society
Correspondence: trhahn@nms.kyunghee.ac.kr
Institutions: Departments of Genetic Engineering and Chemistry, Plant Metabolism Research Center, Kyung Hee University, Suwon, South Korea
Methods: 13C NMR, 1H NMR, SDS-PAGE, extraction, CC, RP-HPLC, enzymatic assay, precipitation, spectrophotometry, evaporation, centrifugation
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