Abstract:

A calcium precipitation method to separate total polyphenols from a 70% ethanol extract of dried powdered
Akebia trifoliate peel was proposed and optimized by response surface methodology. The yield of total polyphenols was
investigated as a function of precipitator dosage, precipitation temperature and time. The results showed that the optimum
precipitation conditions that provided maximum total polyphenol yield of 5.103 7% were obtained when 50 mL of the extract
was precipitated by adding 90 mL of clear saturated limewater at 70 ℃ for 38 min. There was a good agreement between the
predicted and experimental data for total polyphenol yield. The separated precipitate contained 84.417 4% total polyphenols.

Key words: Akebia trifoliate, total polyphenols, response surface methodology, calcium precipitation