Fingerprint analysis of Flos Lonicerae japonicae using binary HPLC profiling

Binary chromatographic profiling was employed in fingerprint analysis of Flos Lonicerae japonicae, the flower bud of Lonicera japonica Thunb. Standardized procedures were used to develop the profiling for both aqueous and ethanolic extracts. Other species in the previous Chinese Pharmacopoeia and some in folk remedy were successfully differentiated from L. japonica Thunb. by hierarchiral cluster analysis of the chromatographic profiles. Correlation analysis showed that six chromatographic peaks in ethanolic extract were positively correlated with in vitro bacteriostasis activity. Two standard fingerprints were developed with 10 genuine samples of L. japonica Thunb. Similarity analysis with a limited number of samples showed a fair consistence in the chromatographic profiling of L. japonica Thunb. from various sources and two harvests, and significant differences from other species. Combination use of the two fingerprints demonstrated confirmative identification and quality assessment of Flos Lonicerae japonicae.