To provide a scientific basis for the selection of the appropriate drying method for Mentha Haplocalyx Herba (MHH), determine 2 monoterpenes, 4 phenolic acids and 5 flavonoids in MHH by GC-MS and UPLC-TQ-MS methods, and investigate the effects of the drying methods on the changes in contents of these analytes. The qualities of products obtained with different drying methods were evaluated by the multivariate statistical method of Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). Results showed that the drying methods had the greatest impact on menthol, caffeic acid, and rosemary acid, which were followed by chlorogenic acid and diosmetin-7-O-glucoside. The contents in these analytes processed with hot-air-drying method were higher than those with microwave-drying and infrared-drying methods at the same temperatures. The contents in these analytes processed under low temperature (40-45 °C) were higher than those under higher temperature (60-70 °C). Above all, the contents in phenolic acids processed with microwave fixation (exposed under microwave at 100 °C for several minutes) were obviously higher than those of not being processed, showing an inhibition of some enzymes in samples after fixation. The TOPSIS evaluation showed that the variable temperature drying method of 'Hot-Air 45-60 °C' was the most suitable approach for the primary drying processing of MHH. The results could provide the scientific basis for the selection of appropriate drying method for MHH, and helpful reference for the primary drying proces of herbs containing volatile chemical components.
Desiccation ; methods ; Flavonoids ; analysis ; Hydroxybenzoates ; analysis ; Mentha ; chemistry ; Monoterpenes ; analysis

To establish the water dynamics model for drying process of Angelicae Sinensis Radix, the Weibull distribution model was applied to study the moisture ratio variation curves, and compared the drying rate and drying activation energy with the drying methods of temperature controllable air drying, infrared drying under different temperatures (50, 60, 70 degrees C). The Weibull distribution model could well describe the drying curves, for the moisture ratio vs. drying time profiled of the model showed high correlation (R2 = 0. 994-0. 999). The result proved that the drying process of Angelicae Sinensis Radix belonged to falling-rate drying period. For the drying process, the scale parameter (a) was related to the drying temperature, and decreased as the temperature increases. The shape parameter (β) for the same drying method, drying temperature had little impact on the shape parameter. The moisture diffusion coefficient increase along with temperature increasing from 0.425 x 10(-9) m2 x s(-1) to 2.260 x 10(-9) m2 x s(-1). The activation energy for moisture diffusion was 68.82, 29.60 kJ x mol(-1) by temperature controllable air drying and infrared drying, respectively. Therefore, the Weibull distribution model can be used to predict the moisture removal of Angelicae Sinensis Radix in the drying process, which is great significance for the drying process of prediction, control and process optimization. The results provide the technical basis for the use of modern drying technology for industrial drying of Angelicae Sinensis Radix.
Angelica sinensis ; chemistry ; Desiccation ; methods ; Models, Theoretical ; Water

Spray drying technology is one of the most commonly used unit operations in the production of traditional Chinese medicine(TCM) preparations, offering advantages such as short drying time and uniform product quality. However, due to the properties of TCM extracts, such as high viscosity, strong hygroscopicity, and poor flowability, there is limited scope to solve the problems of wall adhesion and clumping in spray drying from the macroscopic perspective of pharmaceutical production. Therefore, it has become a trend to study and optimize the spray drying process from the microscopic point of view by investigating single droplet evaporation behavior. Based on the reaction engineering approach(REA), the single droplet drying system, as a novel method for studying droplets, collects parameter data on individual TCM droplets during the drying process and uses the REA to process the data and establish predictive models. This approach is crucial for understanding the mechanism of TCM spray drying. This paper summarized and analyzed the cha-racteristics of various single droplet systems, the application of REA in single droplet drying systems, and its significance in optimizing the process, predicting drying states, and shortening the development cycle in the field of TCM spray drying, and looked ahead to the prospects of this method, including the introduction of new parameters and imaging techniques, aiming to provide a reference for further research in the field of TCM spray drying.
Medicine, Chinese Traditional ; Spray Drying ; Desiccation/methods* ; Temperature ; Technology

The philosophy of quality by design (QbD) is now leading the changes in the drug manufacturing mode from the conventional test-based approach to the science and risk based approach focusing on the detailed research and understanding of the production process. Along with the constant deepening of the understanding of the manufacturing process, the design space will be determined, and the emphasis of quality control will be shifted from the quality standards to the design space. Therefore, the establishment of the design space is core step in the implementation of QbD, and it is of great importance to study the methods for building the design space. This essay proposes the concept of design space for the production process of traditional Chinese medicine (TCM) preparations, gives a systematic introduction of the concept of the design space, analyzes the feasibility and significance to build the design space in the production process of traditional Chinese medicine preparations, and proposes study approaches on the basis of examples that comply with the characteristics of traditional Chinese medicine preparations, as well as future study orientations.
Desiccation ; Drug Compounding ; methods ; Feasibility Studies ; Medicine, Chinese Traditional ; methods ; Risk ; Temperature ; Time Factors

OBJECTIVETo optimize the conditions of the vacuum belt drying process (VBD) for drying Panax notoginseng extract and compare with methods of vacuum freezing drying and spray drying.

METHODThe optimum conditions of VBD were obtained by orthogonal design and validated by determinations of moisture content of the dried product and recovery of active ingredients. Experiments on different drying methods were also conducted.

RESULT AND CONCLUSIONThe optimum conditions are as follows, the feeding speed was 15 mL x min(-1), the belt speed was 4 mm x min(-1), and the heating temperature was (105, 100 degrees C). Comparing with the drying methods of vacuum freezing drying and spray drying, vacuum belt drying possesses some advantages, such as higher recovery of active ingredients, less moisture content of dried product and better overall yield.

To improve the spray drying effect of extract of Wenjing Zhitong Prescription, this study takes the yield, hygroscopic property and the fluidity of dry powder as indexes to screen out auxiliary materials, and the proportion of the auxiliary materials was optimized based on the mixing design experiment; based on that, HPLC method was established for the determination of glycyrrhizin and 6-gingerol in spray powder, the yield of spray powder and the retention rate of the two index components were taken as indexes to further optimize the spray drying parameters. The finally selected auxiliary materials were light magnesium oxide, maltodextrin and silica, and regression equations of dry powder yield, moisture absorption rate, angle of rest with proportion of auxiliary materials were established, and the optimized proportion of auxiliary materials was dry paste-light magnesium oxide-maltodextrin-silica=0.5∶0.305∶0.145∶0.05; according to the optimized drying process parameters of Wenjing Zhitong Prescription, initial temperature was 60 ℃, air inlet temperature was 130 ℃, air flow rate was 35 m~3·h~(-1), atomizing pressure was 40 mm, and liquid inlet speed was 4.5 mL·min~(-1). Under these conditions, the dry powder yield was 90.28%, the retention rate of glycyrrhizin was 74.51%, and the retention rate of 6-gingerol was 72.10%. In this study, optimized auxiliary materials can improve the yield of spray drying and the property of spray powder, and the optimized processing conditions were good for retaining the unstable gingerol components, which can lay a foundation for the further preparation research of meridian warming and pain relieving prescriptions, and provide reference for extract of other traditional Chinese medicine extracts that are difficult to spray drying.
Chemistry, Pharmaceutical/methods* ; Desiccation/methods* ; Drugs, Chinese Herbal/chemistry* ; Hot Temperature ; Medicine, Chinese Traditional ; Powders

Modern drying technology was used to explore suitable drying process to provide scientific basis for improving drying processing methods of Scrophulariae Radix. Controlled temperature and humidity drying, vacuum drying apparatus, microwave vacuum drying apparatus, short infrared drying device were used to gain samples for analyzing. The character appearance, concentration of main components and power consumption indicators were chosen for preliminary judging. Six major components, including iridoids and phenylpropanoids were analyzed by UPLC-MS/MS method. The contents of polysaccharides were determined by UV-visible spectrophotometry. The character appearance with controlled temperature and humidity drying and short infrared drying meet the pharmacopoeia standard (Ch. p, edition 2015), while samples with vacuum and microwave vacuum drying apparatus didn't. Compared to fresh sample, concentrations of harpagide, harpagoside, aucubin and catalpol were lower in the dried samples. Angoroside-C showed no significant change before and after drying. Concentration of acteoside increased after drying. Samples with controlled temperature (70 degrees C) and humidity (15% - 10%) drying had high content and short drying time. The better drying process of Scrophulariae Radix was controlled temperature and humidity drying. The method will provide the reference for the drying technology standard of roots medicine.
Desiccation ; methods ; Drugs, Chinese Herbal ; chemistry ; Plant Roots ; chemistry ; Quality Control ; Scrophularia ; chemistry

OBJECTIVETo study the influence of different drying methods on the quality of Schisandrae Chinensis Fructus and thus provide useful reference for its proper drying methods.

METHODSchisandrae Chinensis Fructus was processed by eight drying methods including vacuum freeze drying, natural drying in the shade, drying in the sun, oven drying and vacuum drying under different temperature. The contents of the functional ingredients includes chisandrin, gomisin D, gomisin J, schisandrol B, angeloylgomisin H, angeloylgomisin Q, gomisin G, schisantherin A, deoxyschisandrin, schisandrin B, schisandrin C, 5-HMF, total aids and total sugars. The main components change after drying were analyzed by HPLC, ultraviolet spectrophotometry and potentiometric titration. Principal component analysis (PCA) was carried out by SPSS software to evaluate the quality of different processed products from Schisandrae Chinensis Fructus.

RESULTAll these results are in accordance with the requirements of Chinese Pharmacopoeia published in 2010, the contents of schisandrin and total eleven lignans were the highest using vacuum drying, and 5-HMF were the lower, oven drying made little difference but with lower schisandrin and higher 5-HMF as the heat increased.

CONCLUSIONDifferent drying methods have significant influence on the quality of Schisandrae Chinensis Fructus. Oven drying under 5°C should be adopted to substitute drying in the sun according to the China Pharmacopoeia published in 2010 for Schisandrae Chinensis Fructus by comprehensive analysis of the cost, content and practicality.

Effects of different drying methods including sun drying, steamed, boiled, constant temperature drying (at 40, 50, 60 °C) on appearance, hardness, rehydration ratio, dry rate, moisture, total ash, extractive and polysaccharides contents were studied to provide the basis of standard processing method for Tulipa edulis bulbus. The results showed that the treatments of sun drying and 40 °C drying showed higher rehydration ratios, but lower dry rate, higher hardness, worse color, longer time and obvious distortion and shrinkage in comparison with other drying methods. The treatments of 60 °C constant temperature drying resulted in shorter drying time, lower water and higher polysaccharides content. Drying time is shorter and appearance quality is better in the treatment of steaming and boiling compared with other treatments, but the content of extractive and polysaccharides decreased significantly. The treatments of 50 °C constant temperature drying led to similar appearance quality of bulb to commercial bulb, and it resulted in lowest hardness and highest dry rate as well as higher rehydration ratio, extractive and polysaccharides content, moderate moisture and total ash contents among these treatments. Based on the results obtained, 50 °C constant temperature drying is the better way for the processing of T. edulis bulbus.
Color ; Desiccation ; methods ; Plant Stems ; chemistry ; Polysaccharides ; analysis ; Quality Control ; Tulipa ; chemistry ; Water ; analysis

To study the impact of five different origin processing methods, namely natural drying, drying in baking shop, drying by microwave heating, drying in drum and drying with sulphur fumigation, on the quality of Lonicerae Japonicae Flos from Donghai cultivation base in Jiangsu Province, with the contents of chlorogenic acid and galuteolin and the similarity in HPLC fingerprints as the evaluation indicators. The results showed that different origin processing methods had significant impact on the content of chlorogenic acid and the similarity in HPLC fingerprints, but with no significant difference on the content of galuteolin. By means of drying by microwave heating and drying in drum, the samples showed higher contents of chlorogenic acid, respectively 3.67% and 3.39%. The similarities of HPLC fingerprints were 0.815 and 0.793, respectively. By means of the drying in baking shop and the drying with sulphur fumigation, the contents of chlorogenic acid in the samples were 2. 87% and 2. 53% , respectively. The similarities of HPLC fingerprints were 0.964 and 0.765, respectively. The lowest content of chlorogenic acid in naturally dried samples was 1.92%. The similarity of HPLC fingerprints was 0.940. According to the findings as well as the internal control standards for Lonicerae Japonicae Flos herbs of Jiangsu Kanion Pharmaceutical Co. , Ltd. , the optimum processing method for Lonicerae Japonicae Flos from Donghai cultivation base was the drying in baking shop. This study provided a theoretical basis for determining the processing method for Lonicerae Japonicae Flos from Donghai cultivation base of Jiangsu Province.
China ; Desiccation ; methods ; Drugs, Chinese Herbal ; chemistry ; Lonicera ; chemistry ; growth & development ; Quality Control