Interactions between thrombin and natural products of Millettia nitita var. hirsutissima using capillary zone electrophoresis

A sensitive and selective high-performance analytical method based on capillary zone electrophoresis (CZE) was developed for investigating interactions between natural products isolated from Millettia nitita var. hirsutissima and thrombin qualitatively and quantitatively for the first time. The results showed that, compared with positive and negative control, the compounds ZYY-5 (genistein-8-C-β-d-apiofuranosyl-(1→6)-O-β-d-glucopyranoside), ZYY-6 (calycosin), ZYY-8 (isoliquiritigenin), ZYY-9 (formononetin), ZYY-12 (gliricidin), ZYY-13 (8-O-methylretusin), FJ-2 (dihydrokaempferol), FJ-3 (biochanin), FJ-5 (afromosin) and XC-2 (hirsutissimiside F) interacted with thrombin, while ZYY-1 (sphaerobioside), ZYY-2 (formononetin-7-O-β-d-apiofuranosyl-(1→6)-O-β-d-glucopyranoside), ZYY-3 (genistein-5-methylether-7-O-α-l-rhamnopyranosyl-(1→6)-O-β-d-glucopyranoside), ZYY-4 (retusin-7,8-O-β-d-diglucopyranoside), ZYY-7 (symplocoside), ZYY-10 (ononin), ZYY-11 (genistin), ZYY-14 (afromosin-7-O-β-d-glucopyranoside), ZYY-15 (lanceolarin), FJ-1 (liquiritigenin), FJ-4 (7,2-dihydroxy,4-methoxyisoflavan) and XC-1 (sphaerobioside) had no binding to thrombin. This indicated that the reported CZE method for the determination of compound–thrombin interactions is powerful, sensitive and fast, and requires less amounts of reagents, and further, it can be employed as a reliable alternative to other methods.