This research provides an improvement for the method of Douglas to determine pentose and hexose sugars in mixed sugars. Specific absorption wave of 553 nm for pentose derivatives and 408 nm for hexose derivatives are selected for determination, and the interference from pentose sugar to hexose sugar is corrected with multiple linear regression method. The results show that the interference from pentose sugar is reduced greatly after multiple linear regression calibration; the error is lower than 5.0 %. The experimental results show a satisfying precision and accuracy, with a recovery range from 95.1 % to 106.8%. This method is suitable for simultaneously rapid determination of pentose and hexose sugars in practical application.
