[Material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on supramolecular chemistry of Chinese medicine].

The present study aimed to explore the material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on the supramolecular chemistry of Chinese medicine.Dynamic light scattering and scanning/transmission electron microscopy were used to characterize the morphological characteristics of supramolecules in the decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma.The chemical composition of supramolecules, as well as the dissolution and release processes of supramolecules and the medicinal components of Coptidis Rhizoma decoction, was determined by the high-performance liquid chromatography-mass spectrometry.The differences in "bitter-cold" medicinal properties between Rhei Radix et Rhizoma decoction, Coptidis Rhizoma decoction, and co-decoction were analyzed by sensory evaluation, electronic tongue, mouse diarrhea model, and pathological indicators.The anthraquinones/tannins and alkaloids interacted to form supramolecules with a scale of about 400 nm when Rhei Radix et Rhizoma and Coptidis Rhizoma were decocted together, which delayed the dissolution and release of the active components represented by berberine. Compared with the consequence of single drug administration at 4 g·kg~(-1), the combination of the two drugs at 8 g·kg~(-1) significantly alleviated the "bitter-cold" properties.The effective components interacted to form supramolecules in the co-decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma, which affected the dissolution and release of the effective components of Chinese medicinal decoction, thereby alleviating the "bitter-cold" properties.The findings of this study provide a new idea for revealing the scientific compatibility of Rhei Radix et Rhizoma and Coptidis Rhizoma.

A new strategy based on acid-alkali complexation for rapidly and accurately fishing phytochemicals in Sennae Folium.

Objective: There are some anthraquinones, anthraquinones and flavonones in Sennae Folium which exhibited significant acidity, such as sennoside A/B and sennoside C/D. The current strategies used in separating these components are mainly based on conventional column chromatography which is time consuming, laborious and costly. This study is aimed at exploring a method of precipitation extraction of acid components in Sennae Folium. Using alkaloid as a "hook", it is reasonable to use the principle of "acid-alkali complexation" to "fish" the acidic components in Sennae Folium. Methods: Isothermal titration calorimeter (ITC) was used to measure the extraction efficiency of different alkaloids. Then, alkaloid determined by ITC was mixed with extracting solution of Sennae Folium to form complex. High performance liquid chromatography coupled with mass spectrometry (HPLC-MS2) was used to investigate the ingredients "fished" by berberine (Ber). The mechanism of "fishing" process was explained by ITC, optical activity, fluorescence spectrometry and scanning electron microscope. Results: The ITC results proved that the choice of "hook" was particularly important in the process of "fishing". Among the hooks, the fishing efficiency of the isoquinoline alkaloids (Ber) was the highest, reaching 10.3%. Nine ingredients were detected and determined by HPLC-MS2, and the main components were sennoside A/B and sennoside C/D. Based on ITC test of Ber and sennoside A, the combination mechanism of the two ingredients was a chemical reaction with a nearly binding ratio (2:1). Fluorescence and optical properties of the active ingredients were changed after complexation. By scanning electron microscope, we found that two types of components had obviously self-assembled behavior during the formation process. Conclusion: Ber successfully "fished" the main acidic components, sennoside A/B and sennoside C/D, from Sennae Folium. Combined with different characterizations, the "fishing" process was determined as a chemical association reaction induced by electrostatic interaction or π-π stacking. Therefore, with special identification ability, the "fishing" process had the potential of practical application.

[New qualities control strategy of Scutellaria baicalensis by isothermal titration calorimetry].

It has been focused on that there will be precipitates when decoction of Scutellariat Radix mixed with Coptidis Rhizoma. Precipitation was derived from interaction between acidic and basic compounds. This study was based on the interaction between active ingredients after compatibility, strived to explore whether it was feasible to judge the qualities of different Scutellariat Radix by isothermal titration calorimetry (ITC), build a new method established to characterize the qualities of traditional Chinese medicine by taking a series of active ingredients as index. We selected Scutellariat Radix (including three batches of different Scutellariat Radix bought from market and immature Scutellariat Radix which usually was used as adulterant) in different batches as the samples. First, we used ITC to determine the binding heat of the reactions between berberine and the decoctions of different Scutellariat Radix. The test showed that the binding heat of berberine titrated Scutellariat Radix was Scutellariat Radix A (－317.20 µJ), Scutellariat Radix B (－292.83 µJ), Scutellariat Radix C (－208.95 µJ) and immature Scutellariat Radix (－21.53 µJ), respectively. We chose deionized water titrated by berberine (2.51 µJ) as control. The heat change of berberine titrated immature Scutellariat Radix was much less than berberine titrated Scutellariat Radix. Then we determined the absorbance of different decoctions of Scutellariat Radix by UV Spectrophotometry on the maximum absorption wavelength, and the result is： Scutellariat Radix A (0.372), Scutellariat Radix B (0.333), Scutellariat Radix C (0.272), immature Scutellariat Radix (0.124). The absorbance of immature Scutellariat Radix was also less than Scutellariat Radix. The result of ITC assay was corresponded to UV spectrophotometry test. In conclusion, ITC could be used to characterize the quality of Scutellariat Radix. The new method to characterize the qualities of traditional Chinese medicine by taking a kind of active ingredients as index building by ITC was simple, scientific and feasible.