Analysis of interaction property of bioactive components in Flos Lonicerae Japonicae with protein by microdialysis coupled with HPLC-DAD-MS

Interaction of the Flos Lonicerae Japonicae (FLJ) with protein was studied by microdialysis coupled with HPLC-DAD-MS. Eight compounds were identified by comparing their t(R), UV data and MS data with reference compounds. microdialysis recoveries and binding degrees of compounds in FLJ with bovine serum albumin (BSA) were determined. Recoveries of microdialysis sampling ranged from 51.3 to 73.2% with relative standard deviation (RSD) below 3.1%, and the binding degrees of those compounds to BSA ranged from 4.8 to 61.2 (0.3 mm BSA) and from 11.1 to 76.2% (0.6 mM BSA), respectively. The results showed that the binding properties of compounds in FLJ were influenced by pH. Furthermore, the binding degrees of five reference compounds were determined separately under the same conditions, the binding degrees of chlorogenic acid, luteolin-3-O-glucoside and 4,5-di-O-caffeoyl quinic acid was lower in FLJ than in single compound solution, on the contrary the binding degree of caffeic acid and rutin was higher in FLJ, which indicated that a significant effects of the interaction of compounds with each other on their binding degrees to BSA. The results showed that there were ten compounds had interaction with BSA, eight of them were the proven active compounds, and the other two compounds had similar binding degree with the proven active compounds, so the ten compounds might possess potential activities.