Study On The Correlation Of Drying Methods And Quality Of Salvia Extract

Traditional Chinese medicine extract is an important intermediate for the preparation of modern Chinese medicine formulations.Its quality directly affects the molding process and the quality of the final product.The evaluation and regulation of the quality of Chinese medicine extracts is a bottleneck problem that restricts the modernization of traditional Chinese medicine.Drying is the key to the formation of Chinese herbal extracts,and the drying technology is closely related to the quality of Chinese herbal extracts.Therefore,how to regulate the quality of Chinese herbal extracts from the drying process is an important issue that needs to be solved urgently to achieve high quality and low energy consumption of traditional Chinese medicine preparations.In present research,Salvia which is of heat-sensitive components was taken as the research object,and its extract powders were prepared by different drying technology.Furthermore,the physical fingerprint spectrum was employed to evaluate the physical properties of the extracts,and the relationships between the drying process parameters,the physical and chemical properties of the extract powders and powder compressibility were analyzed by correlation analysis.The main findings and conclusions are as follows:The first part was explained the effect of drying method on physical and chemical properties of Salvia extract.Using Salvia extract as raw material,the three different drying strategies including vacuum drying,spray drying,and vacuum microwave drying were used to assess the influence on the contents of tanshinone IIA and salvianolic acid B in the Salvia extract powders and the physical properties like particle size and its distribution,specific surface area,pore volume,density,fluidity,moisture content,and hygroscopicity.The results showed that the physical and chemical properties of the extract powders were significantly different by different drying methods.The powders obtained by vacuum drying were proved high content of tanshinone IIA and moisture content,large particle size and particle size distribution.The powders received from spray drying were detected low content of tanshinone IIA,high content of salvianolic acid B,small particle size,large specificsurface area,pore volume and viscosity and good properties in powder compression molding.The powders gain from vacuum microwave drying had low moisture content,small specific surface area and viscosity,and poor powder formability.The second part was detailed the comprehensive evaluation of physical properties of extract powders.Based on thirteen physical indicators involving particle size,particle size distribution width,particle size range,bulk density,tap density,Hausner ratio,angle of repose,compression,viscosity,specific surface area,porosity,moisture content,and moisture absorption rate,the physical fingerprint spectrum of traditional Chinese medicine extract powder was established.And all of physical properties were further summarized as uniformity,filling,fluidity,formability and stability to characterize the physical properties of the powders.Besides,the compressibility of the extract powders was analyzed by index of parameter,index of parametric profile,and index of good compression.The results show that the physical fingerprint spectrum can not only be used for the comprehensive characterization of powder physical properties,but also can be used to assist in determining the compressibility of the powder and help understand the influence of physical properties on the powder formability.It can be used as a new model for evaluating the quality of Chinese herbal extracts.In the third part,the study of drying method and quality of Salvia extract was further explored.Firstly,the SPSS software was used to perform bivariate analysis of different drying process parameters and physicochemical properties of Salvia extract powder,and the relationship between drying method and physical and chemical properties of the extract powder was studied.During the drying process under reduced pressure,the content of salvianolic acid B was negatively correlated with the drying temperature.The bulk density of the powder was negatively correlated with the relative density of the extract.In the process of spray drying,the pressure is an essential factor affecting the quality of Salvia extract.The spray pressure is positively related to the content of tanshinone IIA,specific surface area,pore volume,viscosity,and hygroscopicity,but it is negatively related to the particle size of the powder.In vacuum microwave dryingprocess,the quality of Salvia extract was significantly relied on the drying time,which is negatively correlated with the content of tanshinone IIA and salvianolic acid B,the specific surface area and pore volume of the powder,but is positively correlated to the powder bulk density.Secondly,using multivariate statistical analysis methods(Partial Least Squares Regression),the SIMCA-P+ software was applied to examination the correlations between the formability of Salvia extract powder,various drying process parameters and the physical properties of the powder.The results showed that the drying temperature was of great influence on the compressibility of Salvia extract powder during the reduced pressure drying process,and two of them were negatively correlated.In spray drying,the spray pressure and the density of extracts have a great influence on the formability of Salvia extract powder.The moldability of the powder was negatively correlated with the density of the extract,and positively correlated with the spray pressure.In the vacuum microwave drying process,the compressibility of the Salvia extract powder was relatively higher influenced by the drying time,and the two were negatively correlated.As a result,the formability of the extract powder obtained from all drying processes was significantly related to the particle size,specific surface area,pore volume,and viscosity of the powder simultaneously.In summary,our investigation took the drying method and the quality of Salvia extract as the entry point,clarified the regulation relationship between different drying process parameters and the quality of Salvia extract,and proved the essential factors in the compressive formability of Salvia extract powder.At the same time,the concept of physical fingerprinting was further introduced into the evaluation of the quality of extract powder,which provided scientific evidence for the appraisal of the quality of Chinese herbal extracts.