Exploration of nanofiltration conditions for separation of alcohol precipitation liquid during preparation of Reduning Injection by Box-Behnken design combined with flux attenuation / 中国中药杂志

This study employed Box-Behnken design combined with flux attenuation to explore the nanofiltration conditions for separation of alcohol precipitation liquid during the preparation of Reduning Injection and discussed the applicability of nanofiltration in the separation of the liquid with high-concentration ethanol. The effects of nanofiltration molecular weight cut-off(MWCO) and pH on the rejection of chlorogenic acid, 3,5-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid were consistent with the principles of pore size sieving and charge effect, respectively. The rejection of the three phenolic acids was reduced by concentration polarization effect caused by trans-membrane pressure(TMP). The swelling of membrane surface decreased the pore size and membrane flux for effective separation. Chlorogenic acid and 4,5-dicaffeoylquinic acid were more sensitive to pH and ethanol concentration than 3,5-dicaffeoylquinic acid. A certain correlation existed between the compound structure and the separation factors of nanofiltration, and the separation rules were associated with the comprehensive effect of charge effect, pore size sieving, concentration polarization, steric hindrance and so on.

Chemical constituents of triterpenoid saponins from Glycyrrhiza glabra / 药学学报

Ten triterpenoid saponins were isolated and purified from the water extract of Glycyrrhiza glabra by polyamide resin combined with macroporous resin column chromatography, ODS medium pressure column chromatography and semi-preparative RP-HPLC. Their structures were elucidated by physicochemical properties, NMR and MS spectra, and determined as 3β-O-[β-D-glucuronpyranosyl-(1→2)-β-D-glucuronpyranosyl]-30β-O-β-D-glucuronpyranosyl-oleanane-11-oxo-12(13)-ene (1), 3β-O-[β-D-glucuronpyranosyl-(1→2)-β-D-glucuronpyranosyl]-30β-O-α-L-rhamnopyranosyl-oleanane-11-oxo-12(13)-en-22β,30-diol (2), uralsaponin C (3), licorice-saponin A3 (4), licorice-saponin P2 (5), 22β-acetoxyl-glycyrrhizin (6), macedonoside A (7), 29-hydroxyl-glycyrrhizin (8), licorice-saponin G2 (9), glycyrrhizin (10). Compounds 1 and 2 are two new compounds and named as licorice-saponin R3 and licorice-saponin S3.

Analysis of quality difference based on Astragalus membranaceus var. mongholicus in genuine region / 中国中药杂志

This work is to establish the fingerprint of Astragalus membranaceus var. mongholicus by HPLC-ELSD method, and to analyze the simulated wildness degree of A. membranaceus var. mongholicus in the genuine region of Inner Mongolia, Ningxia and Gansu. Compared with wild A. membranaceus var. mongholicus, the quality differences of A. membranaceus var. mongholicus in the genuine region were analyzed by identification of chromatographic peaks and similarity evaluation, cluster analysis(CA), principal components analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA). HPLC fingerprints of A. membranaceus var. mongholicus in different genuine regions are established. The qualitative analysis of mass spectrometry identified 18 components. The similarity evaluation shows that the similarity of 32 batches of A. membranaceus var. mongholicus samples was 0.688-0.993. Among them, the similarity of samples in Shanxi, Inner Mongolia, Ningxia is 0.688-0.993, 0.835-0.989, 0.934-0.988, respectively and the similarity of samples in Gansu is 0.729-0.876 except No. 25 sample. The results of CA show that the samples of A. membranaceus var. mongholicus can be grouped into four categories according to the production area except the No. 11 and No. 25 samples. The results of PCA indicate that 32 batches of A. membranaceus var. mongholicus samples can be clustered according to quality and origin, and the quality of A. membranaceus var. mongholicus in Inner Mongolia is the closest to the wild breed. The results of OPLS-DA indicate that there are six components that can distinguish the wild and domestic A. membranaceus var. mongholicus, which are malonylastragaloside Ⅰ, astragaloside Ⅰ, calycosin-7-O-β-D-glycoside-6″-O-malonate, calycosin-7-O-β-D-glycoside, formononetin-7-O-β-D-glycoside-6″-O-malonate, and astrapterocarpan-3-O-β-D-glycoside-6″-O-malonate. The established method can be used to analyze differences between A. membranaceus var. mongholicus origin and planting environment, and can provide references for the protection and replacement of wild A. membranaceus var. mongholicus resources, and the cultivation, processing and production of A. membranaceus var. mongholicus.

Textual Research on Origin of Alismatis Rhizoma in China Pharmacopoeia / 中国实验方剂学杂志

This paper origin studies the origin of Alismatis Rhizoma in Chinese pharmacopoeia， and puts forward some suggestions for modification. Through the changes in the records of the source of Alismatis Rhizoma in the various versions of the Chinese Pharmacopoeia and the records of Flora of China and Materia Medica of China，it is found that the source of Alismatis Rhizoma in the Chinese Pharmacopoeia is confused. Specifically， the Chinese name of Alismatis Rhizoma does not correspond to the Latin name. As a common Chinese herbal medicine，Alismatis Rhizoma has a large market circulation. Many classic Chinese medicine prescriptions released by China Food and Drug Administration contain Alismatis Rhizoma. The development of the classic Chinese medicine prescriptions will further increase the market circulation of Alismatis Rhizoma. As a major national move to promote the development of traditional Chinese medicine， the study for classic Chinese medicine prescriptions requires defining the origin of the medicinal materials used，and the confused origin of Alismatis Rhizoma recorded in the Chinese Pharmacopoeia seriously hinder the development of the classics. Therefore，in order to regulate the origin of Alismatis Rhizoma， ensure the clinical efficacy and promote the development of classic Chinese medicine prescriptions，the confused origin of Alismatis Rhizoma in the Chinese Pharmacopoeia has to be resolved as soon as possible. Based on the analysis of the changes of Alismatis Rhizoma's producing areas in the past dynasties， it is found that the producing areas of Alismatis Rhizoma have continuous changed from Wei and Jin dynasties to present， and finally formed the current situation of Sichuan as the main producing area. In comparison of chemical composition，origin and market circulation of Alismatis Rhizoma in Sichuan Province that is the most productive， and Fujian Province that is the best quality， it is found that the two species are different in every aspects. Nowadays，Alisma plantago-aquatica occupies the majority of the market， which doesn't conform to Alisma orientale as specified in the 2015 edition of the Chinese Pharmacopoeia. Therefore， through textual research and analysis， it is suggested that both A. plantago-aquatica and A. orientale. Shall be used as the origin of Alismatis Rhizoma. In the 2015 edition of Chinese Pharmacopoeia，Cassiae Semen，Schizonepetae Herba，Aisaematis Rhizoma，Fibraureae Caulis and Ajugae Herba have the same problem. This paper provides ideas for the revision of sources of traditional Chinese medicine.

Comparative study of water characteristic components of Glycyrrhiza uralensis from three geographical regions by chemical pattern recognition combined with muti-component qualitative and quantitative analysis / 中国中药杂志

Thirty-two batches of cultivated and wild Glycyrrhiza uralensis were obtained from three geographical regions. Comparative study of water characteristic components of G. uralensis from three geographical origins was conducted by PCA,OPLS-DA chemical pattern recognition combined with LC-TOF/MS and muti-component analysis. The similarity of fingerprints of 32 batches of medicinal materials ranged from 0. 903 to 0. 999. Patterns recognition could be used to distinguish cultivated G. uralensis in Gansu and Xinjiang areas from cultivated and wild plants in Inner Mongolia. Then a total of thirty-one common constituents were identified by LC-TOF/MS analysis coupled with standard compounds information. The contents of four flavonoid glycosides and five saponins were determinated by HPLC and compared using One-way ANOVA. The results showed that there was no significant difference in the contents of 5 triterpenoid saponins among the three regions,but the contents of 4 flavonoid saponins showed the trend of Inner Mongolia >Gansu≈Xinjiang( P<0. 05). In the same Inner Mongolia region,the contents of 4 flavonoid glycosides and 5 triterpenoid saponins in wild plant was significantly higher than that in cultivated plants( P<0. 01). In addition,the contents of liquiritin,isoliquiritin,licorice-saponin A_3,22β-acetoxyl-glycyrrhizic acid and uralsaponin B in Gansu and Xinjiang were obviously lower than those in Inner Mongolia,but the contents of glycyrrhizic acid,the main component of G. uralensis,were not different in the three geographical regions. In Inner Mongolia,the contents of liquiritin,isoliquiritin,licorice-saponin A_3,licorice-saponin G_2 and glycyrrhizic acid in wild plants were significantly higher than those in cultivated plants. In conclusion,qualitative/quantitative analysis of multi-index components combined with pattern recognition could effectively evaluate the quality of cultivated and wild licorice in different regions. It was helpful for us to understand the reality of licorice in different regions,and provided scientific basis for the development and comprehensive utilization of licorice resources.

Removing Bacterial Endotoxin from Glycyrrhizic Acid for Injection by Ultrasonic-assisted Ultrafiltration Technology / 中国药学杂志

OBJECTIVE: To remove bacterial endotoxin from glycyrrhizic acid for injection by ultrasonic-assisted ultrafiltration technology. METHODS: On the basis of clarifying the influences of molecular weight cut off, ultrasonic power, glycyrrhizic acid concentration and pH,the ultrafiltration transmittance of glycyrrhizic acid and the rejection of bacterial endotoxin were selected as indexes to optimize the parameters for ultrasonic-assisted ultrafiltration. RESULTS: The impact of glycyrrhizic acid concentration was relatively low. The optimal separation conditions were as following: molecular weight cut off 10×103, ultrasonic power 300 W and pH 7.7. The predicted value of the ultrafiltration rejection of bacterial endotoxin was 93.7%, meanwhile the transmittance of glycyrrhizic acid was 92.2%, which was close to the model-predictive value. CONCLUSION: This mathematical model has good regression with high fitting degree, and can solve the separation contradiction between glycyrrhizic acid and bacterial endotoxin. This study provides scientific data for the purification of pharmaceutics in which saponins are the main components.

Multi-index evaluation of applicability of nanofiltration separation of salvianolic acid B in organic phase / 中草药

Objective: To explore the applicability of nanofiltration separation of salvianolic acid B in organic phase. Methods The rejection rate, mass transfer coefficient, membrane flux, membrane durability and membrane integrity were selected as indexes to evaluate the applicability of nanofiltration for the separation of salvianolic acid B raw material in organic phase from the eluate of macroporous resin. Results The experiment showed that there was a negative relationship between rejection rate and membrane molecular weight cut-off. Meanwhile, the mass transfer coefficient of salvianolic acid B was decreased and the membrane flux was obviously decayed with the increase of ethanol concentration. Through the membrane durability and integrity evaluation, the rejection performance of NFG nanofiltration membrane was stable with the increasing of separation time. Also, the membrane flux decreased first and then increased and maintained stable. At the same time, the charge characteristic of the membrane separation layer was stable, but the effective separation aperture was increased by the combined effects of membrane fouling, additives shedding and so on. Conclusion Based on the comprehensive analysis, NFG nanofiltration membrane could meet the requirements of the separation of low concentration ethanol solution, and had good applicability. The applicability of nanofiltration separation in organic phase was analyzed comprehensively with salvianolic acid B as example, providing theoretical and technical support for nanofiltration separation of phenolic acids in organic phase.

Effect of solution environment on ultrafiltration separation of Panax notoginseng total saponins based on molecular state / 中草药

Objective: To clarify the effect of solution environment on ultrafiltration separation of Panax notoginseng total saponins (PNS) based on the molecular state. Methods: In the experiment, the transmittance and surface tension were selected as indexes for analyzing the effect of ethanol, inorganic salts, surfactants, and pH on the molecular state of PNS. And then, ethanol, NaCl, and pH were selected as influencing factors to analyze the separation rule of notoginsenoside R1 (R1) and ginsenoside Rb1 (Rb1). Results: The intermolecular interaction force of saponins was weakened by increasing the ethanol concentration; The pH value promoted saponin ionization, increased critical micelle concentration, and increased PNS ultrafiltration transmittance; The salting out effect of inorganic salt reduced the critical micelle concentration and PNS transmittance; The surfactant type was related to the ultrafiltration separation behavior of PNS. Rb1 was more sensitive to the factors than R1 by response surface methodology. Conclusion: The effect of solution environmental factors on the ultrafiltration separation of PNS was clarified by the combination of single factor analysis and response surface methodology. And the saponins can be separated purposefully by dynamically adjusting the molecular state.

Enhanced separation behavior of ephedrine in organic solution by nanofiltration mass transfer model / 中国中药杂志

Based on the nanofiltration mass transfer model, the enhanced separation behavior of ephedrine in organic solution was studied. In the experiment, the sensitive region of ethanol concentration and pH on the rejection of ephedrine was screened out by Box-Behnken central composite experiment design. Furthermore, to analyze the separation regularity of ephedrine and organic solution, the correlation between mass transfer coefficient and concentration of organic solvent was fitted with the changed organic solution by nanofiltration mass transfer mathematical model. Experiments showed the enhanced separation behavior, the decrease in the mass transfer coefficient while the increase in ethanol concentration from 20% to 40%, MWCO at 450 and pH 6.0. Under the same conditions, the enhanced separation behavior was appeared as the solvent changed into methanol and acetonitrile, the enhanced effect was positively correlated with the concentration of the three common organic solvents, and the effect order was acetonitrile>ethanol>methanol. This study took ephedrine as an example, and explored the mechanism of nanofiltration separation in the environment of organic solution, so as to provide references for nanofiltration separation for heat-sensitive traditional Chinese medicine of alkaloid.

Enhanced separation behavior of ferulic acid in organic solution by nanofiltration / 中草药

Objective To explore the enhanced separation behavior of ferulic acid in organic solution by nanofiltration. Methods In the experiment, molecular weight cut-off (MWCO) of nanofiltration membrane, ethanol concentration, and solution pH were selected as influencing factors to find the sensitive region of ethanol concentration and pH on the retention rate of ferulic acid with Box-Behnken central composite experiment design. And then, the separation rule of ferulic acid with organic solution was analyzed, the correlation between mass transfer coefficient and concentration of organic solvent was fitted with the changed organic solution by nanofiltration mass transfer mathematical model. Results Experiments indicated that the enhanced separation behavior appeared and the mass transfer coefficient decreased as the ethanol concentration increased from 20% to 40% with MWCO 450 and pH 8.0. Under the same condition, the enhanced separation behavior happened as the solvent was changed into methanol and acetonitrile, and the enhanced effect was positively correlated with the concentration of the three common organic solvents, the effect rule was ethanol ≈ methanol > acetonitrile material. Conclusion The enhanced separation effect of nanofiltration was related to the type and concentration of organic solvent. And taking ferulic acid as an example, the mechanism of nanofiltration separation in the environment of organic solution was studied, and the results provided references for nanofiltration concentrate for heat-sensitive traditional Chinese medicine of phenolic acid in organic solution.

The correlation of molecular structure and nanofiltration mass transfer behavior of alkaloids / 药学学报

Based on the charge repulsion and solution-diffusion effect in nanofiltration separation, the correlation among mass transfer behavior, solution environment and molecular structure of three typical alkaloids from medicine was analyzed by nanofiltration mass mathematical model. The experiment revealed a linear relationship between ln[(1-Ro)·Jv/Ro] and Jv, and the regression coefficients were all greater than 0.9. Compared with the ultrafiltration separation behavior conforming to molecular sieve, the mass transfer coefficient of three alkaloids under different pH was pH 3.00 < pH 7.00 < pH 10.00. As the pH changed, the state of alkaloid transit from ionic state to a free state, the alkaloid could easily approach the membrane surface and pass through the nanofiltration membrane with charge repulsion and solution-diffusion effects, and the results were verified by the membrane adsorption tendency. The nanofiltration mass transfer of alkaloids is related to the state and molecular weight. In the ionic state, the charge effect produces separation behavior, and the molecular state is related to the molecular weight. The separation mechanism of nanofiltration for alkaloids was clarified further by analyzing the correlation of nanofiltration mass transfer behavior and molecular structure. The results of nanofiltration technology provide references for separation of alkaloids at room temperature with fast separation and low energy consumption.

Design and implementation of Xinshenghua granule traceability system based on data authenticity / 中国中药杂志

The quality of traditional Chinese medicine affects the clinical efficacy and the market research at home or abroad, which is closely related to the standardization of production. At present, Chinese market still exist in drug quality and nonstandard production phenomenon. In addition to the existing GMP production standards, it is still necessary to ensure the authenticity and reliability of traditional Chinese medicine by means of retrospect. Based on the Xinshenghua granule, starting from the authenticity of the whole process of production, this study designs and constructs the traditional Chinese medicine traceability system which is equipped with the Internet platform by using two-dimensional code as a trace tool. By making authentic record of the production process and quality transfer, it is convenient for consumers to know the drug information. The production traceability system provides guarantee for the standardization of traditional Chinese medicine development, in order to obtain the production source，the testing quality, whereabouts and responsibility.

Correlation of molecular weight and nanofiltration mass transfer coefficient of phenolic acid composition from Salvia miltiorrhiza / 中国中药杂志

Based on the molecular sieving and solution-diffusion effect in nanofiltration separation, the correlation between initial concentration and mass transfer coefficient of three typical phenolic acids from Salvia miltiorrhiza was fitted to analyze the relationship among mass transfer coefficient, molecular weight and concentration. The experiment showed a linear relationship between operation pressure and membrane flux. Meanwhile, the membrane flux was gradually decayed with the increase of solute concentration. On the basis of the molecular sieving and solution-diffusion effect, the mass transfer coefficient and initial concentration of three phenolic acids showed a power function relationship, and the regression coefficients were all greater than 0.9. The mass transfer coefficient and molecular weight of three phenolic acids were negatively correlated with each other, and the order from high to low is protocatechualdehyde >rosmarinic acid> salvianolic acid B. The separation mechanism of nanofiltration for phenolic acids was further clarified through the analysis of the correlation of molecular weight and nanofiltration mass transfer coefficient. The findings provide references for nanofiltration separation, especially for traditional Chinese medicine with phenolic acids.

HPLC characteristic fingerprints of Xinshenghua Keli / 中国中药杂志

Xinshenghua Keli is known as the "preferred prescription of postpartum", with large demand in the field of gynecologic medicine. However, the quality of the preparation is uneven in the market, so its clinical efficacy cannot be guaranteed. In order to improve and establish its quality control standard, high performance liquid chromatography (HPLC) was used to establish the fingerprint of Xinshenghua Keli. The detection was performed on Agilent 5 HC-C₁₈ (2) column(4.6 mm×250 mm, 5 microns) with methanol-0.1% formic acid solution as mobile phase for gradient elution, at a flow rate of 1 mL·min⁻¹ with column temperature of 25 °C. The injection volume was 10 μL and detection wavelength was set at the maximum value between 210.0 nm and 400.0 nm by Photo-Diode Array (PDA) detector. The fingerprint of 12 batches of high-quality Xinshenghua Keli was established and 43 common peaks were identified. The similarities of crowned products, 10 batches of ordinary ones made by Jiangsu Rongyu Pharmaceutical and 10 batches produced by different manufacturers were evaluated. The composition identification and source analysis for the common peaks were performed by comparing the retention time of herbal medicines and ultraviolet absorption spectrum, along with high performance liquid chromatography-mass spectrometry (HPLC-MS) technology. The established fingerprint of Xinshenghua Keli, has proven to have good precision, stability and repeatability through the methodology validation, so it can be used to comprehensively evaluate the quality of Xinshenghua Keli.

Analyze nanofiltration separation rule of chlorogenic acid from low concentration ethanol by Donnan effect and solution-diffusion effect / 中国中药杂志

To separate chlorogenic acid from low concentration ethanol and explore the influence of Donnan effect and solution-diffusion effect on the nanofiltration separation rule. The experiment showed that solution pH and ethanol volume percent had influences on the separation of chlorogenic acid. Within the pH values from 3 to 7 for chlorogenic acid in 30% ethanol, the rejection rate of chlorogenic acid was changed by 70.27%. Through the response surface method for quadratic regression model, an interaction had been found in molecule weight cut-off, pH and ethanol volume percent. In fixed nanofiltration apparatus, the existence states of chlorogenic acid determinedits separation rules. With the increase of ethanol concentration, the free form chlorogenic acid was easily adsorbed, dissolved on membrane surface and then caused high transmittance due to the solution-diffusion effect. However, at the same time, due to the double effects of Donnan effect and solution-diffusion effect, the ionic state of chlorogenic acid was hard to be adsorbed in membrane surface and thus caused high rejection rate. The combination of Box-Behnken design and response surface analysis can well optimize the concentrate process by nanofiltration, and the results showed that nanofiltration had several big advantages over the traditional vacuum concentrate technology, meanwhile, and solved the problems of low efficiency and serious component lossesin the Chinese medicines separation process for low concentration organic solvent-water solution.

Optimize concentrate process of alkaloid from Leonurus japonicus by ultrafultration-nanofiltration coupling technology / 中国中药杂志

To optimize the concentrate process of alkaloid from Leonurus japonicus by nanofiltration-ultrafiltration coupling technology with response surface methodology. The experiment showed that after ultrafiltration pre-treatment, the total protein removal rate was 94.38% in aqueous extract from L. japonicus, and the nanofiltration technology had obvious advantages over the conventional concentrate process. The optimal concentrate conditions were as follows：molecular weight cut-off 450, pH 3.07, concentration of stachydrine hydrochloride 80.15 mg•L⁻¹, and concentration of the total alkaloid 285.73 mg•L⁻¹. The cut-off rate was 93.37% and 95.85% respectively for stachydrine hydrochloride and the total alkaloid under the optimum conditions, with a relative error of 0.79% and 1.16% respectively. The combination of Box-Behnken design and response surface analysis can well optimize the concentrate process of L. japonicus by nanofiltration, and the results provide the basis for nanofiltration concentrate for heat-sensitive traditional Chinese medicine.

Correlation of molecular state of caffeic acid from Perilla frutescens and its nanofiltration mass transfer process / 中草药

Objective To explore the correlation of molecular state of caffeic acid from Perilla frutescens and its nanofiltration mass transfer process. Methods The pH value of solution was changed and the free-dissociation ratio was adjusted with caffeic acid as an index, the rejection and membrane flux of the corresponding initial concentration and operating pressure in different existence conditions were collected. Based on the solution-diffusion effect and charge effect in nanofiltration separation, the linear equations between the rejection and mass transfer coefficient was constructed, the correlation between mass transfer coefficient and initial concentration was established, the mathematical models which based on the operating pressure and initial concentration to predict the rejection of caffeic acid was developed and used to verify its applicability by aqueous extract of P. frutescens. Results Experiments indicated that there was a linear relationship between operation pressure and membrane flux. Besides, mass transfer coefficient and initial concentration of caffeic acid were positively correlated with each other by solution-diffusion effect and charge effect. The mass transfer coefficient of dissociated caffeic acid was less than those of free state and free-dissociation. Moreover, on the basis of power function relationship between mass transfer coefficient and initial concentration, the results showed that the predicted rejections of caffeic acid from P. frutescens water extract using mathematical model approximate well to real ones. Conclusion The mass transfer coefficient of caffeic acid is associated with existential state and initial concentration. The predicted model of nanofiltration separation has a preferable applicability to caffeic acid and provides references for nanofiltration separation, especially for heat-sensitive traditional Chinese medicine.

Exploring correlation between molecular state and nanofiltration mass transfer process of synephrine from Citrus aurantium / 中国中药杂志

Based on the solution-diffusion effect and the charge effect theory in nanofiltration separation, the correlation between initial concentration and mass transfer coefficient was constructed to establish a mathematic model of synephrine in mass transfer process and verify its applicability. The experimental results showed that there was a linear relationship between operation pressure and membrane flux. Meanwhile, the membrane flux was gradually decayed with the increase of solute concentration. Besides, mass transfer coefficient and initial concentration of synephrine showed power function correlation with each other by solution-diffusion effect and the charge effect, and the regression coefficients were greater than 0.9. The mass transfer coefficient of dissociation synephrine was less than that in the state of free and free-dissociation. Moreover, on the basis of power function relationship between mass transfer coefficient and initial concentration, the results showed that the predicted rejections of synephrine from Citrus aurantium water extract by use of the mathematical model approximated well to real ones, verifying that the model was practical and feasible. The unclear separation mechanism of nanofiltration for alkaloids was clarified preliminary by the predicted model of nanofiltration separation with synephrine as the example, providing theoretical and technical support for nanofiltration separation, especially for traditional Chinese medicine with alkaloids.

Optimization of nanofiltration concentration process of Sophora flavescens extract by coupling technology of response surface methodology and regulating Donnan effect / 中草药

Objective: Response surface analysis and regulating Donnan effect methodology were used to optimize the matrine concentration by nanofiltration techonology. Methods: On the basis of single factor experiment results, molecular weight cut-off (MWCO) of nanofiltration membrane, concentration and pH were selected as influencing factors to evaluate the retention rate of matrine and total alkaloids with Box-Behnken central composite experiment design, and then, the optimal concentration parameters were calculated in the conditions of pH 6-7 to regulate Donnan effect between alkaloids and nanofiltration membrane. Results: The retention rate of matrine was of positive relevance with the ethanol concentration. The optimal concentration parameters were as follows: cutting off molecular weight of 150, pH of 6.19, concentration of 204.3 μg/mL, ethanol concentration of 15%, the retention rate of matrine and total alkaloids were 94.41% and 97.63%, respectively. Conclusion: The combination of ethanol regulation Donnan effect and response surface analysis can well optimize the concentration process of S. flavescens extract by nanofiltration, and the results provide the references for nanofiltration concentration for heat-sensitive Chinese materia medicia.

Establishment of a rapid method to evaluate ultrafiltration membrane aperture for pharmaceutical industry / 中草药

Objective: To solve the technical bottleneck in the application of membrane technology in pharmaceutical industry and to establish a fast and feasible method for evaluating molecular weight cut-off (MWCO) of ultrafiltration membrane. Methods: Based on works, Panax notoginseng saponins (PNS), R1, Rg1, Rb1, and Rd, were selected as indexes for filtering with series ultrafiltration membranes, the retention rate of PNS was accumulated and analyzed with different MWCOs (1×103-1 × 105). Results: The relevant equations were fitted by linear and exponential function, the regression coefficients of equations between the retention rates of PNS and MWCOs were bigger than 0.98. Then, the equations were applied for calculating the different MWCOs of being-measured ultrafiltration membranes. Conclusion: Preliminary judgment is obtained by comparison analysis of cumulative retention rate, and then the optimal MWCO under tested membranes is calculated by subsection equations. This research results have provided a simple and rapid method of evaluating the membrane MWCOs for pharmaceutical industries.