Abstract
Background: Codonopsis Radix (CR) as the tonic Chinese herbis is good at benefiting Qi and promoting saliva, while rice-processed CR (RCR) can alleviate the original dryness and more specialize in invigorating the spleen and stopping diarrhea. Despite CR and RCR are long-standing medicines commonly used in clinic, information on their differences in substance basis is limited, let alone dynamic changes of their main chemical components. Given this, a more comprehensive understanding of processing principles in CR is needed.Methods: In this study, a strategy for rapid separation and identification of chemical constituents in crude CR and RCR was developed by HPLC-Q-TOF-MS/MS. Moreover, chemical constituents (lobetyolin and atractylenolide III) with significant content change were quantitatively determined by HPLC-QQQ-MS, 5-hydroxymethylfurfural (5-HMF) was quantified by HPLC, and codonopsis pilosula polysaccharides (CPPS) was measured by phenol-sulphuric acid method.Results: A total of 28 compounds were identified from CR and RCR, including 12 organic acids, 6 phenylpropanoids, 5 hexanol glycosides and hexylene glycosides, 2 polyacetylenes, 1 alcohol compound, 1 sesquiterpene and 1 aldehyde. In order to explore the dynamic changes from raw CR to processed RCR, the content of representative components in several samples collected during processing was determined. The quantitative results indicated that the contents of lobetyolin, atractylenolide III and CPPS were lower in RCR than these in CR, and 5-HMF was newly formed in processed products, which manifested chemical composition change before and after processing. Conclusions: Processing principles and dynamic changes of CR were preliminarily elucidated. Lobetyolin, atractylenolide III, 5-HMF and CPPS were recommended as quality markers to distinguish CR from RCR. Since the established method is rapid, accurate and readily applicable, it will be helpful for quality control and identification of crude CR and RCR.