Study on Extraction Technology for Chlorogenic Acid from Sweet Potato Leaves by Orthogonal Design

The optimum extracting technology of chlorogenic acid from sweet potato leaves was studied by orthogonal test. This study used L16 (45) orthogonal table to take orthogonal test, considering five indexes such as alcohol concentration, liquid material ratio, PH value, extraction times, distilled time. The effects of each factor on the extraction of chlorogenic acid in order were as follows: alcohol concentration>extraction times>materials-liquid ratio>PH value >distilled time. The optimal parameters is A2B2C3D4E3, precisely alcohol concentration is 30%, liquid material ratio 1:20(w/v), PH value 5.0, extract times four times, distilled 90 minutes. The content of chlorogenic acid extracted from Sweet potato leaves by the optimum extracting technology reached to 3.517%. The optimum technology is feasible and the content of chlorogenic acid extracted from Sweet potato leaves by the optimum extracting technology is higher. So chlorogenic acid from sweet potato leaves could be used as a new resource to develop.