Effect of different drying methods on the active compounds and browning enzyme activities from the Bud of Lonicerae Confusae

Objective: To choose the best drying method and improve the quality of Lonicerae Confusae, the effect of different drying methods on the enzyme activities and the contents of active compounds from the bud of Lonicerae Confusae was studied. Method: Dehydrating methods of vacuum microwave drying, air blast drying and shade drying were chosen to deal with buds of Lonicerae Confusae. The enzyme activity and the content of total phenoltotal, total flavonoids were determined by spectrophotometer. The contents of chlorogenic acid and luteoloside from different drying methods were determined by HPLC.Results: Using the vacuum microwave drying method, the activities of polyphenol oxidase and peroxidase showed a minimum value, the residual activity remained only 30% and 13% resulting in a slight browning. Total phenols, total flavonoids, chlorogenic acid and luteoloside were all the highest compared with other two drying methods.The residual enzyme activity still remained above 80% dried by shade drying method, the browning happened seriously, the content of active compounds was the least.Conclusion: The different drying methods had greater impact on the active compounds and enzyme activities, the vacuum microwave drying was the best method.