Effects of Different Drying Methods on the Main Components of Forsythia suspensa Flowers / 中国药房

ABSTRACT

OBJECTIVE：To establish the method for the content det ermination of 4 components in Forsythia suspensa flowers by drying in shade ，vacuum freeze-drying ，oven（30，50，70 ℃）and sun ，so as to evaluate the effects of different drying methods on the main components of F. suspensa flowers and screen the optimal drying method. METHODS ：UPLC method was adopted. The determination was performed on Waters ACQUITY UPLC BEH C 18 column with mobile phase consisted of acetonitrile- 0.1％ phosphoric acid aqueous solution （gradient elution ）at the flow rate of 0.3 mL/min. The detection wavelength was set at 230 nm， and column was 35 ℃. The sample size was 1 μL. Euclidean closeness（C）i of different drying methods was calculated by TOPSIS comprehensive analysis method ，and the optimal drying method was defined. RESULTS ：The linear range of forsythiaside A ， rutin，forsythin，（+）-pinoresinol-4-O-β-D-glucopyranoside were 0.007 5-0.037 7，0.027 4-0.137 2，0.001 9-0.009 5，0.005 6-0.028 8 µg（all r＞0.999）. RSDs of precision ，stability（32 h）and reproducibility tests were all lower than 2％. The recoveries were 97.27％-102.53％，100.53％-104.11％，98.45％-104.02％，98.66％-104.82％，respectively；and all RSDs ＜3％（n＝3）. The contents were 1.645 8-4.987 9，11.730 2-20.978 0，0.875 5-2.005 0，2.366 0-5.535 7 mg/g. The content of forsythiaside A was the highest after drying at 30 ℃，rutin and （+）-pinoresinol-4- O-β-D-glucopyranoside were the highest after vacuum freeze-drying，forsythiaside was the highest after drying at 50 ℃ . Results of TOPSIS analysis showed that Ci of F. suspensa flowers by drying in shade ，vacuum freeze-drying ，oven（30，50，70 ℃）and sun were 0.079 9，0.553 5，0.495 4， 0.503 8，0.157 9，0.217 2，respectively；the order of Ci was vacuum freeze-drying ＞ 50 ℃ oven drying ＞ 30 ℃ oven drying＞sun drying ＞70 ℃ oven drying ＞ shade drying. CONCLUSIONS：Established method is simple ，reproducible and can be used for the content determination of 4 components in F. suspensa flowers. The samples are preferably dried by vacuum freeze-drying，followed by 50 ℃ oven drying ，30 ℃ oven drying ， and then dried in the sun and oven at 70 ℃ and finally in the shade.