Objective: To study the HPLC fingerprint and the dynamic changes of alkaloid substances from the long malt with different sprout length in the germination process

and optimize the suitable sprout length from the perspective of chemical composition. Method: WondaSil® C18 column (4.6 mm×250 mm

5 μm) was used with methanol (A)-0.1 mol·L-1 potassium dihydrogen phosphate (B) as the mobile phase for gradient elution at a flow rate of 1.0 mL·min-1. The detection wavelength was set at 270 nm and column temperature was 25℃.The fingerprints for 10 batches of malt medicinal materials were set up

and their similarity assay was carried out to evaluate their quality by Similarity Evaluation System for Chromatographic Fingerprint of TCM (2004A edition)

and HPLC fingerprints of malt in the germination process were compared in the same condition. The dynamic changes of alkaloid substances in malt germination process were studied by HPLC and acid colorimetry. Result: There were nineteen common peaks in the fingerprints of ten batches of samples

of which peak 7 was hordenine. Peaks 5

7

8

10

12

15

16

and 17 were newly added after the germination of barley. The peak area of peaks 1

6

9 and 13 was gradually increased and then decreased to reach the maximum at the sprout length of 0.75 cm; and the peak area of peak 3

5

8

17

18 and 19 was gradually increased and then maintained stable in malt germination process. The content of total alkaloid was the largest at malt sprout length of 0.75 cm. Conclusion: The establishment of HPLC fingerprints of malt can provide reference for the quality control of malt medicinal materials. The chemical compositions of malt have obvious changes in the germination process. The optimal sprout length shall be 0.75-1.00 cm with the content of alkaloid in malt as the index.