Objective A high performance liquid chromatographic (HPLC) method was established for the simultaneous determination of xylitol and L-xylulose in fermentation broth.Methods The chromatographic conditions were as follows:C18 column (250 mm ×4.6 mm) with the temperature 35℃, acetonitrile-water (85∶15,v/v)as mobile phase with the flow rate of 0.8 mL/min.Xylitol was detected by refractive index (RI) detector at 33℃and L-xylulose was determined by ultraviolet ( UV) detector at 210 nm at room temperature.Results This method showed good linearity over the range from 0.50~30.00 g/L with a correlation coefficient of 0.9995 for xylitol and 0.30~30.00 g/L with a correlation coefficient of 0.9986 for L-xylulose. Moreover, the limit of quantification (LOQ) for xylitol and L-xylulose were 0.58 and 0.40,respectively.The limit of determination (LOD) for xylitol and L-xylulose were 0.18 and 0.15,respectively.The relative standard deviations (RSDs) of intraday and interday for xylitol were less than 0.64%and 0.80%,respectively.The intraday and interday RSDs for L-xylulose were less than 0.31%and 0.59%.The recoveries of xylitol and L-xylulose in fermentation broth were between 99.00%-101.00%.Conclusion There was no interference from other constitutes in the fermentation broth by this method.The methods were suitable for the simultaneous determination of the substrate xylitol and the product L-xylulose in fermentation process.

Objective:To investigate the teaching effect of blended teaching mode based on BOPPPS in the teaching of Natural Medicinal Chemistry.Methods:The undergraduate students of grade 2019 majoring in pharmacy of a medical college were selected as the research objects and divided into 2 groups randomly.Students in class 2 were set as the control group(n=27)and students in class 1 were set as the experimental group(n=29).The students of the two classes were taught by the same group of teachers.The control group adopted traditional teaching methods and classroom teaching as the main teaching mode combines with multimedia teaching.The experimental group received blended teaching mode based on BOPPPS.The final examination scores,teaching effects and student satisfaction of the two groups were compared and analyzed.Results:The survey results showed that the teaching effect of the blended teaching model based on BOPPPS was recognized by 96.55%of the students in the experimental group.The final examination score in the experimental group was higher than that in the control group(P＜0.05).The teaching effect of the experimental group was significantly better than that of the control group(P＜0.05),and the satisfaction of students in the experimental group was higher than that in the control group(P＜0.05).Conclusion:The application of blended teaching mode based on BOPPPS in the teaching of Natural Medicinal Chemistry can effectively stimulate students'learning interest and improve the teaching quality.