[Effects of different drying methods and conditions on anthraquinones and tannins in water extract from Radix et Rhiroma Rhei].
OBJECTIVE
To investigate effects of different drying methods on the content of anthraquinones and tannins in water extract from Radix et Rhiroma Rhei (DHY).


METHODS
DHY was dried by freeze drying, vacuum drying, drying under normal press and spray drying respectively until its moisture has been 5%. The content of anthraquinones and tannins of samples by different drying methods was determined and compared with.


RESULTS
The content of total anthraquinones, free anthraquinones, conjugated anthraquinones and tannins of samples by different drying methods was some different. Samples with freeze drying were highest and samples with drying under normal press at 100 degrees C were low.


CONCLUSIONS
Temperature is an important pole in drying process water extract from Radix et Rhiroma Rhei. In our study water extract from Radix et Rhiroma Rhei was stable under 60 degrees C on the whole and unstable when drying exceed in 90 degrees C.
Wang
Qiang
Q
Institute of Traditional Chinese Medicine, 302 Hospital of PLA, Beijing 100039, China.
Luo
Yun
Y
Jin
Cheng
C
Ren
Yong-Shen
YS
Wang
Jia-Bo
JB
Qu
Yi
Y
Xiao
Xiao-He
XH
Zhang
Yi
Y
D000336:Aerosols; D000880:Anthraquinones / Q000032:analysis* / Q000302:isolation & purification*; D005612:Freeze Drying; D011309:Preservation, Biological / Q000379:methods*; D011312:Pressure; D012250:Rheum / Q000737:chemistry*; D013634:Tannins / Q000032:analysis* / Q000302:isolation & purification*; D013696:Temperature; D014867:Water / Q000737:chemistry*
D000336:Aerosols; D000880:Anthraquinones; D013634:Tannins; D014867:Water