ABSTRACT
To provide a scientific basis for the selection and optimization of the modern drying processing method for Angelicae Sinensis Radix (ASR). Three phenolic acids (esters), 6 phthalides were determined by using UPLC-PDA while polysaccharides were determined by UV-Vis spectrophotometry. Then the effects of drying methods on the inner qualities of ASR were evaluated through principle components analysis (PCA) combined with the appearance properties after drying. Results showed that the contents of chlorogenic acid and ferulic acid in samples obtained with controlled temperature and humidity drying (CTHD), medium and shortwave infrared drying (MSID) and microwave vacuum drying (MVD) methods were significantly higher than those with primary drying processing(PDP) method and the fresh samples. Multivariate statistical analysis showed that samples processed with CTHD had more similar general chemical properties with those processed with PDP, suggesting that CTHD was appropriate for the modern primary drying processing of ASR. With samples processed with traditional PDP method as reference, the CTHD method was further optimized in the processing parameters for ASR by orthogonal experiment design. Considering the consumption of drying power and time and other parameters, the modern drying parameters for the primary drying processing of ASR were finally optimized as follows: controlled temperature and humidity drying at 40-45 ℃, relative humidity below 25% and target moisture content about 50% in the first stage of drying process, tempering for 12-24 h, and then drying under the conditions of temperature at 50-60 ℃, relative humidity below 20% and fan frequency at 30-40 Hz in the second stage. The study provided the scientific evidence for the selection of appropriate drying method and suitable parameters for the modern primary drying processing of ASR, as well as the beneficial exploration and practice on the formation of technical standard of primary drying processing for roots and rhizomes types herbal medicines.
ABSTRACT
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.
Subject(s)
Angelica sinensis , Chemistry , Desiccation , Methods , Models, Theoretical , WaterABSTRACT
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.
Subject(s)
Desiccation , Methods , Flavonoids , Hydroxybenzoates , Mentha , Chemistry , MonoterpenesABSTRACT
Objective: To study the dynamic changes of aerial parts of Salvia miltiorrhiza during different growth periods based on the contents of seven kinds of salvianolic acids, and determine the value of aerial parts of S. miltiorrhiza. Methods: UPLC-TQ/MS method was applied. The separation was performed on Acquity UPLC BEH C18 (100 mm×2.1 mm, 1.7 μm). The mobile phase was composed of acetonitrile and 0.1% aqueous formic acid by gradient elution. The flow rate of the mobile phase was 0.4 mL/min, and the column temperature was at 35℃. Results: The stems and leaves of S. miltiorrhiza were rich in salvianolic acids, but tanshinones were not detected in them. The content of salvianolic acids in stems and leaves were the highest in July or August besides salvianolic acid A and gradually dropped off till the lowest in December. The content of salvianolic acids in flowers reached maximum during the full-bloom stage. The dynamic change trend is not obvious before full-bloom stage, and its content sharply dropped when flowers began to fade. Conclusion: The aerial parts of S. miltiorrhiza were abundant in salvianolic acids, especially rosmarinic acid and salvianolic acid B, and the contents in luxuriant growth period were significantly higher than those in radix and rhizome of S. miltiorrhiza, which showed that the aerial parts were the important resources to obtain the salvianolic acids.