Objective:

2

To investigate the effects of black bean juice with different stewing times on the appearance character and the content changes of effective components of Polygoni Multiflori Radix Praeparata.

Method:

2

HPLC was employed with Agilent ZORBAX Extend-C

18

column (4.6 mm×250 mm

5 μm)

a gradient mobile phase of methanol (A)-water (B) was eluted (0-30 min

5%-100%A; 30-40 min

100%A)

the flow rate was 1.0 mL·min

-1

the injection volume was 10 μL and the column temperature was 35 ℃

detection wavelength was set at 280 nm. The contents of stilbene glycoside

emodin

emodin methyl ether

emodin-8-

O

-

β

-

D

-glucoside and emodin methyl ether-8-

O

-glucoside in samples prepared at different processing times were simultaneously determined by HPLC.

Result:

2

The content of stilbene glycoside decreased gradually with the increase of stewing time

compared with 8 h

its content decreased by 76% at 64 h. The contents of emodin-8-

O

-

β

-

D

-glucoside and emodin methyl ether-8-

O

-glucoside increased first

and then decreased

reaching the highest value at 24 h

and then decreased to the level similar to the content of 8 h after 40 h

and then fluctuated slightly. The contents of emodin and emodin methyl ether increased first

and then decreased

reached the maximum when stewed for 32 h

then decreased slowly and tended to be stable.

Conclusion:

2

The stewing time has significant influence on the content of various components in Polygoni Multiflori Radix Praeparata

and the changing trend is different

the processing time of Polygoni Multiflori Radix Praeparata shall be standardized. At the same time

it is not sufficient to take stilbene glycoside and anthraquinones as the indicator ingredients for this decoction pieces

the quality control indicators such as polysaccharides shall be considered.