[Comparative study for freeze-drying and sun-drying on multi-index ingredients of Cordyceps sinensis]

The aim of this paper was to compare the influence of freeze-drying and sun-drying on six main nucleosides and nucleobases of Cordyceps sinensis by HPLC. Hypoxanthine,xanthine,uridine,inosine,guanosine and adenosine were reference substances. HPLC analysis was performed on a GL Inertsustain AQ-C_(18) column( 4. 6 mm×250 mm,5 μm),with mobile phase consisting of water( A)-acetonitrile( B) at the flow rate of 1. 0 mL·min~(-1)( 0-10 min,0-1% B; 10-65 min,1%-3% B). The detection wavelength was 260 nm,the column temperature was controlled at 30 ℃,and the injection volume was 5 μL. The linear ranges of hypoxanthine,xanthine,uridine,inosine,guanosine and adenosine were 1. 025-20. 50( r = 0. 999 8),0. 545-10. 90( r = 0. 999 9),4. 051-81. 02( r = 0. 999 8),4. 044-80. 88( r= 0. 999 9),2. 075-41. 50( r= 0. 999 9),4. 032-80. 64( r = 0. 999 9) mg·L~(-1),respectively. The average recoveries of them( n = 6)were as follows: 102. 3%( RSD 2. 1%),101. 1%( RSD 2. 4%),97. 80%( RSD 1. 7%),101. 8%( RSD 1. 8%),98. 90%( RSD2. 0%) and 98. 10%( RSD 1. 4%),respectively. Each sample was processed by freeze-drying and sun-drying so as to compare the difference between the two drying methods. The contents of six index ingredients were significantly different between freeze-drying and sun-drying sample of C. sinensis. The total contents of six index ingredients in sun-drying sample were higher than that in the corresponding freeze-drying sample. This research results provide the scientific basis for the drying methods and quality evaluation of C. sinensis.