A New Affinity-trapping Method for Isolation of Quinoidal Chalcone Pigments from Aqueous Extracts of Dyer's Saffron Flowers

Abstract

Summary A new method was contributed to isolate water-soluble quinoidal chalcone pigments from aqueous extracts of dyer's saffron florets. Carthamin, precarthamin, safflor yellow A and safflor yellow B were fixed with DEAE-, BD- and BND-cellulose and they were released from the cellulose-pigment complexes by using organic acids for checking their physicochemical characteristics, followed by estimating their recovery rate. Safflor yellow B was separated from a crude extract of dyer's saffron florets by trapping it with BD-cellulose and purified through successive column chromatographies. The chromatographically purified sample was analyzed for identification with authentic safflor yellow B. Based on the experimental findings it was concluded that the pigment can be obtained by the affinitytrapping method without appreciable change of the chromatographic, spectrophotometric and tinctorial characteristics. The newly established method was practically applied to the quantitative determination of safflor yellow B content in dyer's saffron flowers. The results proved that the amount of the pigment changed during flower ageing and that the quantitative expression was closely related with floret elongation.