Profiling the chlorogenic acids of aster by HPLC-MS(n).

Using HPLC-MS(n), 33 chlorogenic acids were identified in an aqueous-alcoholic extract of Aster ageratoides Turcz. flower buds. These were three isomers each of p-coumaroylquinic acid, caffeoylquinic acid, feruloylquinic acid, dicaffeoylquinic acid and diferuloylquinic acid, and six isomers each of p-coumaroyl-caffeoylquinic acid, p-coumaroyl-feruloylquinic acid and caffeoyl-feruloylquinic acid. Only the caffeoylquinic acids and dicaffeoylquinic acids have been reported previously in Asteraceae. Three of the six p-coumaroyl-feruloylquinic acids (3-feruloyl-4-p-coumaroylquinic acid, '3-feruloyl-5-p-coumaroylquinic acid and 4-feruloyl-5-p-coumaroylquinic acid) have not been observed previously in nature. Cis-5-p-coumaroylquinic acid was identified at a concentration ca 25% that of the more common trans isomer. The feruloylquinic acids and diferuloylquinic acids dominated the mono- and di-acyl chlorogenic acid fractions, respectively, making this plant material a useful source of these commercially non-available substances. These 33 chlorogenic acids were not detected in the leaves or stem of A. ageratoides Turcz., or in the flower buds of A. ageratoides Turcz. var. Gerla or A. kalimeris indica (L) Sch. Bip. Only the feruloylquinic acids were detected in the root of A. ageratoides Turcz. It was not possible to detect any 1-acyl chlorogenic acids, any chlorogenic acids with a succinic acid substituent, or any chlorogenic acids based on muco-quinic acid.