title: Dynamic residual complexity of the isoliquiritigenin-liquiritigenin interconversion during bioassay.
abstract: Bioactive components in food plants can undergo dynamic processes that involve multiple chemical species. For example, 2'-hydroxychalcones can readily isomerize into flavanones. Although chemically well documented, this reaction has barely been explored in the context of cell-based assays. The present time-resolved study fills this gap by investigating the isomerization of isoliquiritigenin (a 2'-hydroxychalcone) and liquiritigenin (a flavanone) in two culture media (Dulbecco's modified eagle medium and Roswell Park Memorial Institute medium) with and without MCF-7 cells, using high-performance liquid chromatography-diode array detector-electrospray ionization/atmospheric pressure chemical ionization-mass spectrometry for analysis. Both compounds were isomerized and epimerized under all investigated biological conditions, leading to mixtures of isoliquiritigenin and R/S-liquiritigenin, with 19.6% R enantiomeric excess. Consequently, all three species can potentially modulate the biological responses. This exemplifies dynamic residual complexity and demonstrates how both nonchiral reactions and enantiomeric discrimination can occur in bioassay media, with or without cells. The findings highlight the importance of controlling in situ chemical reactivity, influenced by biological systems when evaluating the mode of action of bioactives.
authors: UIC/NIH Center for Botanical Dietary Supplements Research, Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , 833 South Wood Street, Chicago, Illinois 60612, United States.
authors: Charlotte
authors: C
authors: Simmler
authors: Atieh
authors: A
authors: Hajirahimkhan
authors: David C
authors: DC
authors: Lankin
authors: Judy L
authors: JL
authors: Bolton
authors: Tristesse
authors: T
authors: Jones
authors: Djaja D
authors: DD
authors: Soejarto
authors: Shao-Nong
authors: SN
authors: Chen
authors: Guido F
authors: GF
authors: Pauli
mesh_terms: D001681:Biological Assay; D047188:Chalcones / Q000032:analysis* / Q000737:chemistry*; D003470:Culture Media; D044950:Flavanones / Q000032:analysis* / Q000737:chemistry*; D006801:Humans; D007536:Isomerism; D061986:MCF-7 Cells; D010945:Plants, Edible / Q000737:chemistry*
chemical_list: D047188:Chalcones; D003470:Culture Media; D044950:Flavanones; C040920:isoliquiritigenin; C083152:liquiritigenin