Effects of ultrasonic power on drying kinetics and product quality of licorice extract during ultrasound-assisted vacuum drying.

BACKGROUND: Licorice extract is an important raw material for food additives and medicine. The quality of licorice extract is dictated by the drying process. The commonly used drying methods of licorice extract are not efficient in obtaining high-quality products so alternative techniques need to be developed and researched. In this study, ultrasound-assisted vacuum drying (UAVD) was first utilized to improve drying efficiency and produce a higher-quality product. The changes in water mobility of licorice extract during drying were characterized using low-field nuclear magnetic resonance. In addition, the effects of ultrasonic power on the drying dynamics, the contents of liquiritin and glycyrrhizic acid, the antioxidant capacity and the microstructure formation of licorice extract during the whole drying process were investigated. RESULTS: The drying times for licorice extract to reach equilibrium moisture content were reduced by 9.09-69.70% with UAVD at 40-200 W compared with that without ultrasonic treatment (0 W). Moreover, the proportions of bound water and semi-bound water in fresh concentrate were 3.75% and 96.25%. It was also found that high ultrasonic power promoted the flow of water and the formation of porous structure in licorice extract, which led to the improvement of drying efficiency. The contents of liquiritin (2.444%) and glycyrrhizic acid (6.514%) were retained to a large degree in the dried product at an ultrasonic power of 80 W. The DPPH inhibition rate of UAVD samples with different ultrasonic powers ranged from 84.07 ± 0.46% to 90.65 ± 0.22%. CONCLUSION: UAVD has the advantages of high efficiency and low energy consumption, which may be an alternative technology for vacuum drying widely used in industry. © 2024 Society of Chemical Industry.

[Application of discrete element method (DEM) in pharmaceutical process of solid traditional Chinese medicine preparations].

In recent years, the application of numerical simulation in the research and development(R&D) as well as the pharmaceutical processes of new drugs has expanded considerably. The discrete element method(DEM), an important approach among numerical simulation methods, offers an effective tool for the simulation of discontinuous media. Referring to the research progress of DEM and the formulation of solid traditional Chinese medicine(TCM) preparations in recent years, this paper summarizes and analyzes the application of DEM in the pharmaceutical processes of solid TCM preparations, and discusses the challenges of its application in these processes, in order to provide new methods and ideas for promoting the high-quality production of TCM preparations.

[Current situation and development trend of digital traditional Chinese medicine pharmacy].

The 21st century is a highly information-driven era, and traditional Chinese medicine(TCM) pharmacy is also moving towards digitization and informatization. New technologies such as artificial intelligence and big data with information technology as the core are being integrated into various aspects of drug research, manufacturing, evaluation, and application, promoting interaction between these stages and improving the quality and efficiency of TCM preparations. This, in turn, provides better healthcare services to the general population. The deep integration of emerging technologies such as artificial intelligence, big data, and cloud computing with the TCM pharmaceutical industry will innovate TCM pharmaceutical technology, accelerate the research and industrialization process of TCM pharmacy, provide cutting-edge technological support to the global scientific community, boost the efficiency of the TCM industry, and promote economic and social development. Drawing from recent developments in TCM pharmacy in China, this paper discussed the current research status and future trends in digital TCM pharmacy, aiming to provide a reference for future research in this field.

[Critical influencing factors on quality of traditional Chinese medicine preparations from perspective of process and equipment].

The quality of traditional Chinese medicine preparations is directly related to the safety of patients. Among the various factors, the process and corresponding critical equipment are critical factors influencing the quality of the preparations. To improve the quality of traditional Chinese medicine preparations, this article summarizes and analyzes the problems in the process links and corresponding critical equipment in the manufacturing process of traditional Chinese medicine preparations. Furthermore, a critical quality attribute evaluation system is established based on safety and effectiveness combined with the drug properties, preparation process, and preparation characteristics, providing a basis for the process and equipment improvements aimed at quality enhancement.

[Scientific connotation of temperature control in processing of Chinese medicinal materials based on theory of quality evaluation through morphological identification].

Processing of Chinese medicinal materials is an important part in the Chinese medicine heritage, and the temperature control in the processing has a direct impact on the quality and efficacy of traditional Chinese medicines. However, the processing of Chinese medicinal materials has the problems of subjective temperature judgement, determination of the end point based on experience, unclear processing mechanism, unstable quality of products, and inconsistent processing standards. The temperature control in the processing is reflected in the appearance and internal quality of Chinese medicinal materials. The theory of quality evaluation through morphological identification is developed based on the comprehensive evaluation of the shape, color, taste, and components, which is associated with the temperature control in the processing. To solve the problems above, this paper puts forward the following solutions. The first is literature mining. By review of the ancient medical works and pharmaceutical experience, the temperature control in processing and the evolution of processing methods can be revealed. Second, according to the ancient method, the processing principle can be explored, on the basis of which the processing technology can be innovated. Third, the standard operating procedure(SOP) should be established to quantify the fire temperature, providing a theoretical basis for the formulation of Chinese medicinal material processing standards. Moreover, it provides a basis for improving the quality of processed products and increasing the safety and effectiveness of traditional Chinese medicines.

Chemical Composition Analysis and Discrimination of Essential Oils of Artemisia Argyi Folium from Different Germplasm Resources Based on Electronic Nose and GC/MS Combined with Chemometrics.

In this study, the electronic nose and GC/MS were used to analyze the chemical components of essential oils from different germplasm resources of Artemisia argyi Folium (A. argyi), in order to quickly identify essential oils of A. argyi from different germplasm resources and clarify the differences among different A. argyi samples. The essential oils of A. argyi were extracted by steam distillation. This article describes for the first time that electronic nose combined with chemometrics can distinguish the essential oils of A. argyi from different germplasm, which proves the reliability and potential of this technology. GC/MS was used to identify 134 volatile components from the essential oil of A. argyi. The main bioactive components were cineole, thujarone, artemisia ketone, ß-caryophyllene, (-)-4-terpinol, 3,3,6-trimethyl-1,5-heptadien-4-ol, (-)-α-thujone, camphor, borneol. In addition, the results of principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed that there were significant differences in the essential oils of A. argyi from different germplasm resources, terpenes, alcohols and ketones played an important role in identifying the essential oils of A. argyi from different germplasm resources. This indicates that electronic nose and GC/MS combined with chemometrics can be used as reliable techniques to identify different germplasm resources of A. argyi, and provide certain reference value for quality evaluation, selection of high-quality varieties and rational development of resources of A. argyi.

Effect of Drying Kinetics, Volatile Components, Flavor Changes and Final Quality Attributes of Moslae herba during the Hot Air Thin-Layer Drying Process.

Moslae herba is considered to be a functional food ingredient or nutraceutical due to its rich bioactive components. The present research was carried out to investigate the effects of different temperatures (40 °C, 50 °C and 60 °C) on the drying characteristics, textural properties, bioactive compounds, flavor changes and final quality attributes of Moslae herba during the hot air-drying process. The results showed that the Midilli model could effectively simulate the drying process of Moslae herba. The effective moisture diffusivity ranged from 3.14 × 10-5 m2/s to 7.39 × 10-5 m2/s, and the activation energy was estimated to be 37.29 kJ/mol. Additionally, scanning electron microscopy (SEM) images of Moslae herba samples showed the shrinkage of the underlying epidermal layers and glandular trichomes. In total, 23 volatile compounds were detected in Moslae herba. Among them, the content of thymol increased from 28.29% in fresh samples to 56.75%, 55.86% and 55.62% in samples dried at temperatures of 40 °C, 50 °C and 60 °C, respectively, while the other two components, p-cymene and γ-terpinene, decreased with an increase in the temperature. Furthermore, both radar fingerprinting and principal component analysis (PCA) of the electronic nose (E-nose) showed that the flavor substances significantly altered during the drying process. Eventually, drying Moslae herba at 60 °C positively affected the retention of total phenolics, total flavonoids and the antioxidant capacity as compared with drying at 40 °C and 50 °C. The overall results elucidated that drying Moslae herba at the temperature of 60 °C efficiently enhanced the final quality by significantly reducing the drying time and maintaining the bioactive compounds.

[Application and problems analysis of traditional Chinese medicine volatile oil preparation technology based on ionic liquids].

Ionic liquids(ILs) are salts composed entirely of anions and cations in a liquid state at or near room temperature, which have a variety of good physicochemical properties such as low volatility and high stability. This paper mainly reviewed the research overview of ILs in the application of traditional Chinese medicine(TCM) volatile oil preparation technology. Firstly, it briefly introduced the application of TCM volatile oil preparation technology and composition classification and physicochemical properties of ILs, and then summarized the application of ILs in the extraction, separation, analysis, and preparation of TCM volatile oil. Finally, the problems and challenges of ILs in the application of TCM volatile oil were explained, and the application of ILs in TCM volatile oil in the future was prospected.

[Current research status and application prospect of numerical simulation in traditional Chinese medicine drying].

With the rapid development of computer technology, numerical simulation has gradually become an important method to study drying process and improve drying equipment. Using computer to simulate the drying process of traditional Chinese medicine(TCM) is characterized by intuitiveness, scientificity, and low cost, which serves as an auxiliary means for technical innovation in TCM drying. This paper summarizes the theories of different drying methods and the research status of numerical simulation in drying, introduces the modeling methods and software of numerical simulation, and expounds the significance of numerical simulation modeling in shortening the research and development cycle, improving drying equipment, and optimizing drying parameters. However, the current numerical simulation method for drying process has problems, such as low accuracy, lack of quantitative indicators for the control of simulation results on the process, and insufficient in-depth research on the mechanism of drug quality changes. Furthermore, this paper put forward the application prospect of numerical simulation in TCM drying, providing reference for the further study of numerical simulation in this field.

[Conversion of traditional Chinese medicine (TCM) into nanomedicine:application of theory of unification of medicines and excipients].

In recent years, the use of active substances as excipients or as substitutes for other excipients in the design of modern drug delivery systems has received widespread attention, which has promoted the development of the theory of unification of medicines and excipients in the design of traditional Chinese medicine(TCM) preparations. Adopting the theory of unification of medicines and excipients to design drug delivery systems can reduce the use of excipients and thus the cost of preparations, reduce drug toxicity, increase drug solubility and biocompatibility, enhance synergistic effect, and realize targeted delivery and simultaneous delivery of multiple components. However, the research on the application of this theory in the modern drug delivery system of TCM preparations is still insufficient, with few relevant articles. In addition, the TCM active substances that can be used as the excipients remain to be catalogued. In this paper, we review the types and applications of the drug delivery systems with TCM active substances as excipients and describe their common construction methods and mechanisms, aiming to provide references for the in-depth research on the modern drug delivery systems for TCM preparations.

[Application prospect of reaction engineering approach in studying drying behavior of single droplet during spray drying of traditional Chinese medicine].

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.

[Current status, trends, and challenges of continuous manufacturing technology for oral traditional Chinese medicine solid preparations].

In recent years, continuous manufacturing technology has attracted considerable attention in the pharmaceutical industry. This technology is highly sought after for its significant advantages in cost reduction, increased efficiency, and improved productivity, making it a growing trend in the future of the pharmaceutical industry. Compared to traditional batch production methods, continuous manufacturing technology features real-time control and environmentally friendly intelligence, enabling pharmaceutical companies to produce drugs more efficiently. However, the adoption of continuous manufacturing technology has been slow in the field of traditional Chinese medicine(TCM) pharmaceuticals. On the one hand, there is insufficient research on continuous manufacturing equipment and technology that align with the characteristics of TCM preparations. On the other hand, the scarcity of talent with diverse expertise hampers its development. Therefore, in order to promote the modernization and upgrading of the TCM pharmaceutical industry, this article combined the current development status of the TCM industry to outline the development status and regulatory requirements of continuous manufacturing technology. At the same time, it analyzed the problems with existing TCM manufacturing models and explored the prospects and challenges of applying continuous manufacturing technology in the field of TCM pharmaceuticals. The analysis focused on continuous manufacturing control strategies, technical tools, and pharmaceutical equipment, aiming to provide targeted recommendations to drive the development of the TCM pharmaceutical industry.

Strategies for Taste Masking of Orodispersible Dosage Forms: Time, Concentration, and Perception.

Orodispersible dosage forms, characterized as quick dissolving and swallowing without water, have recently gained great attention from the pharmaceutical industry, as these forms can satisfy the needs of children, the elderly, and patients suffering from mental illnesses. However, poor taste by thorough exposure of the drugs' dissolution in the oral cavity hinders the effectiveness of the orodispersible dosage forms. To bridge this gap, we put forward three taste-masking strategies with respect to the intensity of time, concentration, and perception. We further investigated the raw material processing, the composition of auxiliary material, formulation techniques, and process control in each strategy and drew conclusions about their effects on taste masking.

Ozone episodes during and after the 2018 Chinese National Day holidays in Guangzhou: Implications for the control of precursor VOCs.

The impact of reducing industrial emissions of volatile organic compounds (VOCs) on ozone (O3) pollution is of wide concern particularly in highly industrialized megacities. In this study, O3, nitrogen oxides (NOx) and VOCs were measured at an urban site in the Pearl River Delta region during the 2018 Chinese National Day Holidays and two after-holiday periods (one with ozone pollution and another without). O3 pollution occurred throughout the 7-day holidays even industrial emissions of VOCs were passively reduced due to temporary factory shutdowns, and the toluene to benzene ratios dropped from ∼10 during non-holidays to ∼5 during the holidays. Box model (AtChem2-MCM) simulations with the input of observation data revealed that O3 formation was all VOC-limited, and alkenes had the highest relative incremental reactivity (RIR) during the holiday and non-holiday O3 episodes while aromatics had the highest RIR during the non-pollution period. Box model also demonstrated that even aromatics decreased proportionally to levels with near-zero contributions of industrial aromatic solvents, O3 concentrations would only decrease by less than 20% during the holiday and non-holiday O3 episodes and ozone pollution in the periods could not be eliminated. The results imply that controlling emissions of industrial aromatic solvents might be not enough to eliminate O3 pollution in the region, and more attention should be paid to anthropogenic reactive alkenes. Isoprene and formaldehyde were among the top 3 species by RIRs in all the three pollution and non-pollution periods, suggesting substantial contribution to O3 formation from biogenic VOCs.

Vertical distribution and temporal evolution of formaldehyde and glyoxal derived from MAX-DOAS observations: The indicative role of VOC sources.

Formaldehyde (HCHO) and glyoxal (CHOCHO) are important oxidization intermediates of most volatile organic compounds (VOCs), but their vertical evolution in urban areas is not well understood. Vertical profiles of HCHO, CHOCHO, and nitrogen dioxide (NO2) were retrieved from ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations in Hefei, China. HCHO and CHOCHO vertical profiles prefer to occur at higher altitudes compared to NO2, which might be caused by the photochemistry-oxidation of longer-lived VOCs at higher altitudes. Monthly means of HCHO concentrations were higher in summer, while enhanced amounts of NO2 were mainly observed in winter. CHOCHO exhibited a hump-like seasonal variation, with higher monthly-averaged values not only occurred in warm months (July-August) but also in cold months (November-December). Peak values mainly occurred during noon for HCHO but emerged in the morning for CHOCHO and NO2, suggesting that HCHO is stronger link to photochemistry than CHOCHO. We further use the glyoxal to formaldehyde ratio (GFR) to investigate the VOC sources at different altitudes. The lowest GFR value is almost found in the altitude from 0.2 to 0.4 km, and then rises rapidly as the altitude increases. The GFR results indicate that the largest contributor of the precursor VOC is biogenic VOCs at lower altitudes, while at higher altitudes is anthropogenic VOCs. Our findings provide a lot more insight into VOC sources at vertical direction, but more verification is recommended to be done in the future.

[Stability improvement of Chinese medicinal essential oils based on delivery systems and their application in medical field].

Essential oils from Chinese medicine are popular in the fields such as medicine, food, and cosmetics because of their unique biological characteristics. However, since essential oils are lipophilic compounds with high volatility, poor stability, and strong irritation, various preparation technologies need to be employed to improve stability, reduce irritation, and increase bioavailability. At present, a variety of preparation technologies have been applied to the encapsulation of essential oils. Various encapsulation strategies are formed because of different delivery systems featured with multiple principles and characteristics and are widely used to improve the stability of essential oils. Essential oils of Chinese medicine are widely used in the medical field, and they are under continuous innovation and development in clinical research, the pharmaceutical industry, medical products, etc. The present study summarized various delivery systems that could improve the stability of essential oils and reviewed the applications of essential oils encapsulated in the delivery systems in the medical field to provide re-ferences for the improvement of stability of essential oils and their safety, efficiency, and wide use in the medical field.

[Connotation and mitigation of polyphenolic astringency in Chinese medicine].

Taste is one of the important factors in the design of oral drug preparations. Polyphenols are the secondary metabolites produced in the growth process of Chinese medicine with a variety of physiological activities. However, astringency perceived from polyphenols tastes uncomfortable. As one of the true taste of Chinese medicine, astringency with drying, rough, and wrinkled sensation, seriously affects the texture of Chinese medicine and the compliance of patients. Due to the universality of polyphenolic astringency in Chinese medicine and the weakness of modern research, this study systematically reviewed and summarized the latest research on the mechanism of polyphenolic astringency, the astringency evaluation method, and the astringency-mitigation technology. Through comprehensively analyzing the quantification methods, such as sensory evaluation, animal preference evaluation, chemical evaluation, bionic evaluation, and polyphenol-protein interaction evaluation, the direction of overall astringency assessment with "unified dimension" was proposed. Since the characteristics of Chinese medicine and the mechanism of polyphenolic astringency did not reach a consensus, this study proposed the idea of astringency mitigation suitable for Chinese medicine. This study is intended to deepen the understanding of astringency associated with Chinese medicine, and establish a real and objective astringency evaluation method for Chinese medicine, thus promoting the technique of astringency mitigation of polyphenolic Chinese medicine preparations from trial and error to science.

[Kinetics and variation of volatile components of Atractylodis Macrocephalae Rhizoma during hot-air drying].

The present study explored the kinetics and variation of volatile components of Atractylodis Macrocephalae Rhizoma during the hot-air drying process to obtain the optimal process parameters under multiple goals such as drying efficiency and drying quality. The dry basis moisture content and drying rate curves along with the change of drying time of Atractylodis Macrocephalae Rhizoma were investigated at five levels of drying air temperatures(30, 40, 50, 60, and 70 ℃). The relationship between moisture ratio and time in the drying process of Atractylodis Macrocephalae Rhizoma was fitted and verified by Midilli model, Page model, Overhults model, Modified Page model, Logaritmic model, Two terms Exponential model, and Newton model. Meanwhile, the effective diffusion coefficient of moisture(D_(eff)) and activation energy(E_a) in Atractylodis Macrocephalae Rhizoma were calculated under different drying air temperatures. GC-MS was used to determine the volatile components and content changes of the fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures. The dry basis moisture content and drying rate of Atractylodis Macrocephalae Rhizoma were closely related to the temperature of the drying medium, and the moisture of the Atractylodis Macrocephalae Rhizoma decreased with the prolonged drying time. As revealed by the drying rate curve, the drying rate increased with the increase in hot air temperature, and the migration of moisture was accelerated. The comparison of the correlation coefficient(R~2), chi-square(χ~2), and root mean standard error(RMSE) of each model indicated that the parameter average of the Midilli model had the highest degree of fit, with R~2=0.999 2, χ~2=8.78×10~(-5), and RMSE=8.20×10~(-3). Besides, the D_(eff) at 30-70 ℃ was in the range of 1.04×10~(-9)-6.28×10~(-9) m~2·s~(-1), and E_a was 37.47 kJ·mol~(-1). The volatile components of fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures were determined by GC-MS, and 18, 18, 18, 17, 17, and 18 compounds were identified respectively, which accounted for more than 84.76% of the volatile components. In conclusion, the hot-air drying of Atractylodis Macrocephalae Rhizoma can be model-fitted and verified and the variation law of the moisture and volatile components of Atractylodis Macrocephalae Rhizoma with temperature is obtained. This study is expected to provide new ideas for exploring the drying characteristics and quality of aromatic Chinese medicine.

[Drying effect of Chinese medicinal pills based on new spiral vibration drying technology].

The present study explored the drying effect of new spiral vibration drying technology on Chinese medicinal pills with Liuwei Dihuang Pills, Zhuanggu Guanjie Pills, and Muxiang Shunqi Pills as model drugs. With the drying uniformity, drying time, energy consumption, pill split, dissolution time, and change of index components as evaluation indicators, the drying effect of spiral vibration drying technology on model drugs was evaluated and compared with traditional drying methods, such as hot air drying and vacuum drying in the oven. The dynamic changes of moisture in Liuwei Dihuang Pills with different drying time were investigated. Compared with the traditional drying methods in the oven(hot air drying and vacuum drying) at 80 ℃, the spiral vibration drying only took 80 min, shortened by 80%, with 10%-13% energy consumed. The results showed that the moisture of Liuwei Dihuang Pills was negatively related to the drying time. By virtue of multi-layer countercurrent drying and super resonant fluidization techniques, the new spiral vibration drying technology can significantly improve the drying quality of Chinese medicinal pills, improve the drying efficiency, and enhance the manufacturing capacity of Chinese medicinal pills. This study is expected to provide references for the innovation and development of new drying technology of Chinese medicinal pills.

[Quality control mode based on engineering quality view of Chinese medicine pharmacy].

Due to the characteristics of confusing varieties of Chinese medicinal materials, different sources, complex chemical composition, non-standard preparation process, and non-standard pharmaceutical equipment, the quality of Chinese medicinal preparations is difficult to be controlled and evaluated effectively under the current quality control mode and method of Chinese medicinal preparation. The present study proposed an engineering quality view of Chinese medicine pharmacy and a strategy to control the quality of Chinese medicinal preparations based on the current situation. The "overall, dialectical, and dynamic" multi-factor engineering quality view, covering original medicinal materials, preparation technologies, pharmaceutical equipment, and Chinese medicinal preparations, ensures the traceable process, measurable procedures, and feedback quality. The quality control mode of Chinese medicinal preparation with controllable sources, standardized preparation technologies, green pharmaceutical equipment, and intelligent manufacturing is built up.