Abstract
A simple and sensitive high-performance liquid chromatography-ultraviolet (HPLC-UV) method was developed by exploiting the benefits of phenyl-hexyl column for the simultaneous determination of mono- and di-caffeoylquinic acids in Gynura procumbens plant samples. An optimal chromatographic separation was achieved by using a mobile phase of acetonitrile: 0.25% acetic acid in water (12.5:78.5, v/v) and detection at 330 nm. The limits of detection (LOD) and quantification (LOQ) for the six caffeoylquinic acid standards were in the range of 0.078–0.653 and 0.259–1.795 μg/mL, respectively. The accuracies of the developed method were in the range of 96.84–103.08%, while the corresponding precisions were between 0 and 2.94% for both within-day and between-day analyses, indicating that the method is repeatable and reliable. The mean recoveries were between 87.08 and 117.83%. The method was successfully applied for quantification of caffeoylquinic acids in G. procumbens plant samples. This is the first study on di-caffeoylquinic acids quantification in G. procumbens. Leaves samples contained higher amount of the caffeoylquinic acids compared to stem samples. Of the compounds, 3,5-dicaffeoylquinic acid was found to be the major compound in almost all G. procumbens samples. The method has advantages such as sensitive ultraviolet (UV) detection, short run time with simple isocratic elution system compared to other methods which involved the use of costly instruments, laborious procedures with long run time and complex gradient system. This method can be further extended for routine quality control and analysis of plants or herbal products containing the caffeoylquinic acids.
… MATERIAL AND METHODS Standards and solvents The following four standards:
1,3DC,
1,5DC,
3,4DC and
4,5DC, were purchased from Chengdu
Biopurify Phyto- chemicals
Ltd (Chengdu, China), while CA and 3,5DC were isolated in-house from G. procumbens …