Optimization of the extraction of polyphenolics from young stems of Asparagus officinalis using orthogonal array design

While the young stems of Asparagus officinalis were used as the research object, the optimum conditions for extraction of polyphenolic were investigated by the single factors and orthogonal array design experiment, and the effect of ethanol concentration、extraction time、extraction temperature and solid-to-solvent ratio on polyphenol yield were studied.The result showed that the optimal conditions were as follows: ethanol concentration 50%, solidto-solvent ratio 1 ∶ 15, extraction temperature 80℃ and extraction time 60min. Under this condition, the extraction yield could reach 6.90%.The method was low- cost and easy to operate, thereby could provide technical support for the processing and utilization of asparagus officinalis.