Li Wang,Bolin Lian,Weiwei Wu,Yiping Deng,Yanjie Liu,Lingling Wang,Yuanyuan Li,Zijian Wang,Xiuhua Zhao
Ellagic acid (EA) was produced from pomegranate husk by extraction of tannins followed by acid hydrolysis and purified by antisolvent recrystallization. Response surface methodology, based on a five-level, four-variable central composite design, was employed to find the optimum purification conditions. Under these conditions, high purity and yield of EA was obtained in close agreement with the predicted values by the model. Analyzes of surface morphology and in vitro percutaneous absorption experiments of EA let conclude that the granule morphology of the purified EA was significantly different from the crude EA, and its particle size was much smaller than that of the crude EA. Evaluation in vitro demonstrated that the permeation rate of the purified EA was higher compared with the crude EA.
The content of flavonoids in Gingko biloba extract (GBE) could be increased by antisolvent recrystallization (ASR) using ethanol as solvent and hexane as antisolvent. By means of the single-factor method, the effect of main factors on the content of flavonoids in purified GBE was investigated. Under optimal conditions, the content of flavonoids and ginkgo terpene lactones in purified GBE could be significantly enhanced. In addition, the content of total ginkgolic acid in purified GBE was reduced. The morphologies of raw and purified GBE were characterized by scanning electron microscopy. It was found that the particle size of purified GBE was much smaller than that of raw GBE. At the same time, the saturated solubility could be improved by more than four times.
This study aimed to obtain paeonol with high purity by using the combination of steam distillation and antisolvent recrystallization (ASR) and to reduce the energy consumption and CO 2 emission in the preparation process. First, different experimental parameters were optimized by response surface methodology (RSM). Under the optimal conditions, the purity and yield of the as-obtained paeonol were about 98% and 56.97%, respectively. The physicochemical properties of purified paeonol were tested, showing consistency with those of standard paeonol. The energy consumption and CO 2 emission of the preparation process of ASR and single-solvent recrystallization were also investigated. Results showed that the energy consumption and CO 2 emission of ASR were about 4.41 J/mg and 0.006 kg/mg, respectively, which were 6.89 J/mg and 0.0095 kg/mg lower than those of ethanol recrystallization, respectively, and 50.22 J/mg and 0.0144 kg/mg lower than methanol those of recrystallization, respectively. The above results showed that ASR could obtain paeonol with high purity in a high-efficiency, low-energy, and environmentally protective manner.