Development of liquiritigenin-phospholipid complex with the enhanced oral bioavailability / 中国天然药物

In the present study, liquiritigenin-phospholipid complex (LPC) was developed and evaluated to increase the oral bioavailability of liquiritigenin. A single-factor test methodology was applied to optimize the formulation and process for preparing LPC. The effects of solvent, drug concentration, reaction time, temperature and drug-to-phospholipid ratio on encapsulation efficiency were investigated. LPCs were characterized by UV-visible spectroscopy, differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), and powder X-ray diffractometry (PXRD). The apparent solubility and n-octanol/water partition coefficient were tested. The pharmacokinetic characteristics and bioavailability of the LPC were investigated after oral administration in rats in comparison with liquiritigenin alone. An LPC was successfully prepared. The optimum level of various parameters for liquiritigenin-phospholipid complex was obtained at the drug concentration of 8 mg·mL

Comparative pharmacokinetics of baicalin, wogonoside, baicalein and wogonin in plasma after oral administration of pure baicalin, Radix scutellariae and Scutellariae-paeoniae couple extracts in normal and ulcerative colitis rats

The aim of this study was to investigate the pharmacokinetic profiles of baicalin, wogonoside, baicalein and wogonin after oral administration of pure baicalin, Radix scutellariae and Scutellariae-Paeoniae couple extracts were administered and the pharmacokinetics profiles were compared between normal and ulcerative colitis rats. The plasma concentrations of the four flavonoids were determined by using a simple and rapid high-performance liquid chromatography method. All the rats were divided randomly into two groups [ulcerative colitis and normal groups]. Each group contained three subgroups: pure baicalin, Radix scutellariae and Scutellariae-paeoniae couple extracts subgroup. Each group received oral administration of pure baicalin, Radix scutellariae and Scutellariae-paeoniae couple extracts at the same dose of 200 mg/kg baicalin. The results showed that wogonoside, possibily as a methylated product of baicalin, was found in plasma after oral administration of pure baicalin or formulas to rats. Baicalin and wogonoside demonstrated bimodal phenomenon. Baicalin and wogonoside in Scutellariae-Paeoniae couple extract had shown better absorption than which inpure baicalin and Radix scutellariae extract. Whether oral administration of pure baicalin, Radix Scutellariae or Scutellariae-paeoniae couple extracts, ulcerative colitis rats showed better absorption than normal rats. For example AUC[0-t] of baicalin were: [41.46 +/- 0.62], [59.12 +/- 6.42] and [104.87 +/- 0.86] [micro g/mL] h in UC groups vs [17.77 +/- 0.66], [28.04 +/- 4.06] and [49.01 +/- 4.61] [micro g/mL] h in normal groups, respectively. The pharmacokinetics properties of the four flavonoids differed between ulcerative colitis and normal rats, including AUC[0-t] and C[max] [p < 0.05]