Molecular encapsulation of bioactive ingredients from Xuefu Zhuyu decoction by cyclodextrin-assisted extraction

Enhancing the extraction efficiency of the bioactive ingredients from Chinese medicinal material (CMM) is crucial to effective applications in clinical practice. Herein, focusing on Xuefu Zhuyu decoction (XFZYD) as a classical formula with antithrombotic efficacy, we developed an accessible and environment-friendly method via cyclodextrin (CD) for assisting the extraction of chemical components. The employment of CDs significantly enhanced the extraction efficiency of poorly water-soluble components in XFZYD, from which hydroxypropyl- β -CD (HP- β -CD) showed the best extraction efficiency by comparing to α -CD, β -CD, and γ -CD. Six representative ingredients were focused to systematically perform the encapsulation study between HP- β -CD and guest molecule. The satisfactory association constants of HP- β -CD with the tested compounds were determined by implementing phase solubility method and direct fluorescence technique. The inclusion complexes were studied by DSC and SEM to visualize thermal characteristics and surface textures, which were further confirmed by 1 H NMR spectroscopy. Moreover, theoretical calculations indicated that stable bindings between HP- β -CD and tested compounds were witnessed by various non-covalent interactions. Thus, the formation of the inclusion complex with CD is a very effective method to improve the extraction efficiency of the active compounds from CMM.