Abstract:

Objective: The paper is to determine the contents of reducing sugar and total sugar in Trichosanthis Fructus and its
steamed products by UV-VIS spectrophotometry, and to study the content changes of reducing sugar and total sugar in Trichosanthis
Fructus and its steamed products. Mehtods: With D-glucose anhydrous as standard, the reducing sugar contents in Trichosanthis
Fructus and its steamed products was determined by using 3,5- two nitro salicylic acid（DNS）colorimetric method at the wavelength
of 540 nm, the total sugar contents in Trichosanthis Fructus and its steamed products was determined by using Phenol sulfuric acid
color method at the wavelength of 487 nm. Results: When the reducing sugar was determined, the D-glucose anhydrous had a good
linear relationship with the absorbance in the range of 0.04-0.20 mg（r=0.999 1）, the average recovery was 99.8%, RSD was 0.78％.
When the total sugar was measured, the D-glucose anhydrous had a good linear relationship with the absorbance in the range of 0.005-
0.080 mg（r=0.999 5）; the average recovery was 98.3% , RSD was 1.98% . The contents of reducing sugar and total sugar in
Trichosanthis Fructus before and after steaming were 5.54%, 8.07%, 6.71% and 11.51% respectively. Compared with before steaming,
the content of reducing sugar and total sugar increased, and the difference had statistic significance（P＜0.01）. Conclusion: The
contents of reducing sugar and total sugar in Trichosanthis Fructus increased after steaming.

Key words: Trichosanthis Fructus, steamed products, reducing sugar, total sugar