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[Study on quality indicators for concentration process of supernatant obtained in first ethanol precipitation in
Han Zhang1, Anyi Yan, Xingchu Gong
1College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China.
Abstract:
According to the effect of second ethanol precipitation (SEP) in the production of Danshen injection, the indicators for controlling the quality of a concentration process of the supernatant obtained in the first ethanol precipitation (FEP) were investigated. The concentrated supernatants of FEP with different constituents were prepared and treated with the same amount of ethanol. The parameters which affect phenolic compound retention ratios in SEP supernatant were found using a stepwise regression method. Phenolic compound contents in SEP supernatant were mainly affected by pH and caffeic acid content of the concentrated supernatant of FEP. Caffeic acid content and pH should be set as quality indicators and strictly controlled in concentrating the supernatant of FEP.
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