Kim H O, Durance T D, Scaman C H, Kitts D D
Food, Nutrition and Health, University of British Columbia, 6650 NW Marine Drive, Vancouver, British Columbia, Canada.
J Agric Food Chem. 2000 Sep;48(9):4187-92. doi: 10.1021/jf000246n.
Different drying methods, such as freeze-drying (FD), vacuum microwave drying (VMD), and air-drying (AD), were applied to fresh roots and leaves of Canadian-grown Echinacea purpurea to determine the optimal method for preserving alkamide levels. Using HPLC, six alkamide fractions (alkamides 1, 2, 3, 6a/6, 7, 8/9) were quantitated in dried roots, whereas four alkamide fractions (alkamides 1, 2, 3, 8/9) were measured in dried leaves. Different elution conditions used in HPLC for alkamide analysis did not affect the eluted fractions nor the quantitation of different alkamides. Individual alkamide concentrations in roots and leaves were affected by the drying methods used. To preserve higher levels of total alkamides, FD was found to be the best method, VMD was a superior method for drying roots than AD at 70 degrees C, while AD at 50 degrees C was the preferred method for drying leaves of E. purpurea.
采用不同的干燥方法，如冷冻干燥（FD）、真空微波干燥（VMD）和气干（AD），对加拿大种植的紫锥菊的新鲜根和叶进行处理，以确定保存酰胺生物碱水平的最佳方法。使用高效液相色谱法（HPLC），对干燥根中的六种酰胺生物碱组分（酰胺生物碱1、2、3、6a/6、7、8/9）进行了定量分析，而在干燥叶中测定了四种酰胺生物碱组分（酰胺生物碱1、2、3、8/9）。HPLC用于酰胺生物碱分析的不同洗脱条件既不影响洗脱组分，也不影响不同酰胺生物碱的定量。根和叶中各酰胺生物碱的浓度受所用干燥方法的影响。为了保存较高水平的总酰胺生物碱，发现冷冻干燥是最佳方法，在70℃下，真空微波干燥对根的干燥效果优于气干，而50℃下的气干是干燥紫锥菊叶的首选方法。
