Original: Du Ke, Qin Xuemei Chinese herbal medicine magazine
Rehmannia glutinosa, a plant of ScrophulariaceaeRehmannia glutinosa Libosch. Fresh or dried root tubers. 《Chinese Pharmacopoeia》2015Annual Edition[1]It contains Rehmannia glutinosa (Fresh Rehmannia glutinosa, raw Rehmannia glutinosa) and its processed products, cooked Rehmannia glutinosa, which has different qualities, tastes and effects. Fresh rehmannia glutinosa is cold in nature and tastes sweet and bitter. It has the effect of clearing heat, generating fluid, cooling blood and stopping bleeding; Raw Rehmannia glutinosa is fresh rehmannia glutinosa after baking to ca8; Cooked Rehmannia glutinosa is made by stewing or steaming raw Rehmannia glutinosa with wine. It is warm in nature and sweet in taste. It has the effects of nourishing blood and Yin, tonifying essence and filling marrow. The three drugs are quite different[2].
cookedRehmannia glutinosaProcessing method of[3]The processing method of Lei Gong's theory of firecracker, which was first published by Lei Xuan in the northern and Southern Dynasties, has developed from the original2Secondary steaming and drying developed to nine steaming and nine drying, and then evolved from the processing of a single auxiliary material (wine) to the repeated steaming of a variety of auxiliary materials (wine, Amomum villosum, Poria cocos, etc.), until the current standard was simplified to one-time steaming and wine stewing. The preparation methods of Rehmannia glutinosa are different, mainly including processing methods, auxiliary materials used, and steaming times. Traditional processed products of nine steamed and nine sun dried Rehmannia glutinosa[4]It not only has the advantages of "black as paint, bright as oil, and sweet taste", but also uses the power of rice wine to enhance the effect of cooked Rehmannia glutinosa in activating blood vessels and tonifying blood; At the same time, Rehmannia glutinosa can dissipate its thick Qi through repeated steaming and drying, overcome the wet and greasy nature, and enhance the tonic effect. [5]In order to ensure the quality stability of Rehmannia glutinosa, a scientific and complete quality evaluation system must be established, 《Chinese Pharmacopoeia》2015Radix Rehmanniae Preparata was identified by thin-layer identification of verbascoside under the year edition identification item, and the mass fraction of verbascoside under the content determination item was not less than0.020%It is limited and the evaluation method is relatively simple. In recent years, scholars at home and abroad have done a lot of research work in the chemistry, pharmacology, processing and other aspects of Radix rehmanniae, providing a basis for the quality of Radix Rehmanniae-The effectiveness evaluation laid the foundation. In order to clarify the pharmacodynamic material basis of Rehmannia glutinosa and fully reveal the scientific connotation of its processing, this paper reviews the chemical composition, pharmacological effects and processing research of Rehmannia glutinosa by consulting the literature, and looks forward to comprehensively evaluating the quality of Rehmannia glutinosa from the perspectives of chemistry, pharmacology and different processing degrees in combination with the effect metabolomics, in order to provide a reference for the quality of Rehmannia glutinosa glutinosa-New ideas are provided for the evaluation of efficiency and the determination of processing end points.
1 Changes of chemical composition of Rehmannia glutinosa before and after processing
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1.1 Iridoids and their glycosides
Iridoids and their glycosides from Rehmannia glutinosa[6]Mainly Catalpol, acetylCatalpol, Leonurus glycoside, digitalis glycosideA、B、C、D, digitalis, et al. Digitalis glycosides in Rehmannia glutinosaA、DCatalpol is the most abundant iridoid glycoside in fresh rehmannia glutinosa, and its content decreases after processing. According to reports[7]，9After secondary steaming and sun exposure, the contents of Leonurus glycoside and miritide in Rehmannia glutinosa decreased, while the contents of catalpol and aucubin decreased sharply.
1.2 Phenylethanol glycosides
Phenylethanol glycosides from Rehmannia glutinosa[8-10]It mainly includes verbascoside, salidroside, and digitalis phenylethanol glycosideD, digitoninA1, digitalis phenylethanol glycoside, alloxan glycosidepurpureaside C、darendoside B、decaffeoylacteoside, hydroferulic acid, p-hydroxyphenylethanol echinacoside, isocalycosin, etc. After processing, phenylethanol glycosides are easy to hydrolyze, so they mostly exist in raw Rehmannia glutinosa, and less in cooked rehmannia. For example, the average content of verbascoside in Rehmannia glutinosa is fresh rehmannia glutinosa > raw Rehmannia glutinosa > cooked Rehmannia glutinosa.
1.3 Carbohydrate compounds
The sugar components in Rehmannia glutinosa accounts for a large proportion, and are divided into monosaccharides, oligosaccharides (oligosaccharides) and polysaccharides. The contents of various carbohydrate components in fresh rehmannia glutinosa, raw Rehmannia glutinosa and cooked Rehmannia glutinosa are also different, and the polysaccharide content[11]: Fresh Rehmannia glutinosa（90.2～98.6 mg/g）> Rehmannia glutinosa（65.9 mg/g）> Rehmannia glutinosa（31.3～50.5 mg/g）. Stachyose is the most abundant oligosaccharide in fresh and raw Rehmannia glutinosa[12]. Mannotriose is the main oligosaccharide in cooked Rehmannia glutinosa, because the stachyose in raw Rehmannia glutinosa steaming process is mainly fructose free and mannotriose is generated. According to reports[13].
1.4 Furanal derivatives
,5-（5-HMF）The average content of Rehmannia glutinosa in the order of cooked Rehmannia glutinosa > raw Rehmannia glutinosa > fresh rehmannia glutinosa[12]Other furanal derivatives were found5-(α-D-glucopyranosyl)-2-furancarboxaldehyde（5- GMF）、5-(α-D-glucopyranosyl-(1→6)-α-D-glucopy- ranosyloxymethyl)-2-furancarboxaldehyde（5-GGMF）It was only detected in prepared rehmannia glutinosa, but not in raw Rehmannia glutinosa, and was considered as a marker to rapidly distinguish raw and prepared rehmannia glutinosa[6]。
1.5 trace element
Crude drug processing is a transfer process of trace elements[14]It is generally believed that trace elements in ion-exchange and carbonate bound states are easy to dissolve and be absorbed and utilized by organisms; However, trace elements in oxide bound, organic bound and residual states are relatively stable and difficult to be bioavailed[15]The order of trace element content in Rehmannia glutinosa isCr＞Fe＞Al＞Cu＞Zn＞Mn＞Sr＞Co＞Pb[12]The order of trace element content in Rehmannia glutinosa isFe＞Al＞Cu＞Zn＞Mn＞Sr＞Cr＞Co＞PbAfter raw Rehmannia glutinosa processed into mature Rehmannia glutinosa[16-17]，Fe、Mn、Cu、Zn. The order of trace element content of Rehmannia glutinosa processed with and without wine is basically the same. Prepared rehmannia glutinosaSr、MnThe dissolution rate of was slightly reduced, whileCuThe dissolution rate of Rehmannia glutinosa stewed with water was higher than that of Rehmannia glutinosa stewed with wineZn、Al、Fe.
The processing process can cause qualitative and quantitative changes in a variety of chemical components in Rehmannia glutinosa, mainly focusing on iridoids and their glycosides, phenylethanol glycosides, sugars, furanal derivatives, trace elements and other substances. These changes in chemical composition are the material basis for the changes in the properties of Rehmannia glutinosa.
2 Pharmacological effects of active ingredients of Radix Rehmanniae
After being processed, Rehmannia glutinosa turns from cold to warm, its taste turns from bitter to sweet, its efficacy turns from clear to tonic, and its main functions are nourishing yin and blood, tonifying essence and filling marrow. .
2.1 Effects on the blood system
Digitalis glycosides in prepared rehmannia glutinosaA、DIt can nourish yin, replenish blood and reduce blood sugar[18-19]Catalpol has hypoglycemic effect[20-21]Effects of Rehmannia glutinosa polysaccharide on peripheral blood cell status and serum granulocyte in mice with deficiency of both qi and blood-The levels of macrophage colony-stimulating factor were significantly improved, which could promote the hematopoietic function of the body; White blood cell count of blood deficiency model mice（WBC）, red blood cell count（RBC）, hemoglobin（HB）, platelets（PLT）The protective effect of Rehmannia glutinosa polysaccharide is better than that of the non polysaccharide part and the decoction of Rehmannia glutinosa, and Rehmannia glutinosa polysaccharide is its effective blood tonic part[22-23]Studies have found stachyose and mannotriose[24-25]. Fructose also showed better hematopoiesis[26]。5-HMFIt has certain curative effect on sickle cell anemia and improving Hemorheology[27-28]. prepared rehmannia glutinosaFeThe higher element content may be related to its blood tonic effect.
2.2 Impact on the immune system
Digitalis glycosideA[18,29], verbascoside[2], isocalycosin and echinacoside have immunomodulatory effects. Rehmannia glutinosa polysaccharide[30]It can promote apoptosis and regulate immunity.5-HMFBy suppressing immunityBALB/cMouseTh2Type I immune response, inhibiting total immunoglobulinE（IgE）And ovalbumin specificityIgETo achieve the anti allergic effect[31]. isolated from Rehmannia glutinosa2,5-Dihydroxyacetophenone（DHAP）It can inhibit the inflammatory response induced by lipopolysaccharide stimulated rat macrophages[32]。
2.3 Effects on the central nervous system
Catalpol, verbascoside, echinacoside[33-36]Both have been proved to have good neuroprotective effects. Rehmannia glutinosa polysaccharide can delay the onset latency of isoniazid induced convulsion and reduce the number of animal deaths, suggesting that Rehmannia glutinosa polysaccharide has an inhibitory effect on the central nervous system[37]Mannotriose, an effective component of Rehmannia glutinosa, can protect rat hippocampal nerve cells from damage caused by high concentration of corticosterone by regulating learning and memoryGlucocorticoid receptor, an important protein in signal transduction pathway（GCR）Brain derived neurotrophic factor（BDNF）, serum and glucocorticoid regulated protein kinase（SGK）To improve the deterioration of learning and memory function caused by high concentration of corticosterone[38]Stachyose also has neuroprotective activity[2]。5-HMFIt can block scopolamine induced learning deficits and enhance cognitive function in rats; P-synapsin I, which plays a role in delaying the deterioration of learning and memory function[39-40]。
2.4 liver、Renoprotective effect
Catalpol[41-42], verbascoside[43]It has the function of protecting kidney, digitalis glycosideC, aucubin, wild zizanic acid, salidroside have hepatoprotective activities. Mannotriose has anti liver injury activity[2]。5-HMFBy regulating protein kinasesRLike endoplasmic reticulum kinase-Eukaryotic translation initiation factor2α（PERK-eIF2α）Signaling pathway to protect galactose（GalN）/tumor necrosis factor-α（TNF-α）The injured hepatocytes were protected from endoplasmic reticulum stress-induced apoptosis, which indicated that5-HMFMay be a candidate for drugs to treat liver disease, which can significantly improve alcohol induced liver apoptosis and steatosis[44-45]。
2.5 Other roles
Catalpol has anti gastric cancer and anti oxidative damage effects[46-47], verbascoside can protect ovarian function[48]. Rehmannia glutinosa polysaccharideIt can promote the apoptosis of tumor cells and has a good antioxidant effect[49]Studies have proved that stachyose, mannotriose and raffinose all showed certain inhibitory effects on the growth of laryngeal cancer cells and lung cancer cells, among which stachyose and mannotriose had stronger effects[2]Oligosaccharides such as fructoseIt also has the effect of moistening the intestines and defecating[50]。5-HMFIt can alleviate the hemolysis of red blood cells caused by oxidative damage and has antioxidant activity; Can also induce melanomaA375apoptosis， ; It can inhibit cerebral ischemia-reperfusion injury in rats; It is also a powerful inhibitor of adipogenesis and an enhancer of osteoblastogenesis, which may be one of the components of Radix Rehmanniae Preparata that exert anti osteoporosis effect[51-54]。
In conclusion, the active ingredients of Rehmannia glutinosa show pharmacological effects on blood, immunity and central nervous system, as well as liver and kidney protective activities. Due to the characteristics of multi-component, multi-target and synergistic effects of traditional Chinese medicine, the changes of its pharmacological effects after processing cannot be determined which components are caused by the increase or decrease. The author speculates that the changes of its pharmacological effects may be caused by the changes in the proportion of the components after processing. Synthetic Rehmannia glutinosa24Modern pharmacological research on the main active ingredients according to literature methods[55], usingCytoscapeThe software constructs the chemical base network of Radix Rehmanniae based on the main pharmacodynamic effects (Fig1）。
3 Quality of Rehmannia glutinosa with different processing degrees-Effectiveness evaluation
3.1 Dynamic changes of chemical components in processed Rehmannia glutinosa
Raw Rehmannia glutinosa is bitter, cold and heat clearing, while processed mature Rehmannia glutinosa turns into sweet, warm and nourishing. The study on the dynamic changes of chemical composition in the processing process is conducive to monitoring the processing process, determining the processing end point of nine steaming and nine drying, and dynamically monitoring and evaluating the quality of Rehmannia glutinosa with different processing degrees.
3.1.1 Using infrared spectroscopy（FTIR）Determination of endpoint Fankefeng et al[56]utilizeFTIRStewed Rehmannia glutinosa with wineEvaluate and analyze the processing process and processing endpoint. The results showed that15 hThe indicators tend to be stable and characterized. The（1）Character change: the color completely turns black; The（2）Spectrum features: double strong peaks（1057、1 026 cm−1）（817、797、777 cm−1）、777featurePeak and second derivative spectral peak（819、800、778 cm−1）Equal characterization stability; The（3）Quantitative indicators: the ratio of related peak area continued to decrease, and the peak area ratio of15 h. Zhang Jing et al[57]adoptL9 (34) Orthogonal experimental design to5-HMFThe processing technology of prepared rehmannia glutinosa was screened according to the content of calycosin, reducing sugar, water extract and property score. The results showed that the optimal processing conditions were the amount of yellow wine added40%, repeated9Secondary steaming, each steaming6 h，70 ℃Blast dry.
3.1.2 Using HPLC（HPLC）Dynamic monitoring of material changes during processing by using Mengxianglong et al[5]base onHPLCObjective to explore the influence of processing auxiliary yellow rice wine on the dynamic changes of chemical composition of prepared rehmannia glutinosa obtained by nine steaming and nine drying. The results showed that Catalpol, motherwort glycoside, verbascoside, stachyose, sucrose, raffinose in prepared rehmannia glutinosa by steaming and wine stewing decreased with the increase of steaming and drying times;5-HMF, fructose, glucose and mannotriose increased. In the processing process of the ancient cooked Rehmannia glutinosa with nine steaming and nine drying, the processing auxiliary yellow rice wine had a significant impact on the quality of the processed products, and both the steaming method and the wine steaming method were in the second3、4、6The amount of related substances of Rehmannia glutinosa obtained by secondary steaming and drying showed great fluctuation.
Zhong Lian et al[58-59]The sensor response value of electronic tongue was analyzed by statistical mass method, combined withHPLCAccording to the method, it was found that when Rehmannia glutinosa was steamed for nine times and dried for nine times, as the processing degree deepened, it was steamed and dried for nine times4The contents of catalpol and verbascoside decreased significantly after the second time. and5-HMFAfter steaming and drying2～9The content increased significantly in the second process. A、D. Glucose in P1The content increases obviously during the second steaming and drying, and finally1The content of secondary steaming and drying has a downward trend. Fructose is steamed and dried4The content increased significantly at the second time, and the steam6～9The content of the second time has an obvious downward trend. The correlation analysis showed that the color change during the processing of Rehmannia glutinosa was related to Catalpol, verbascoside5-HMF, digitalis glycosideA, digitalis glycosideDThere were significant correlations. The changes of "odor characteristics" are related to Catalpol, verbascoside5-HMF, digitalis glycosideA, digitalis glycosideDAnd glucose were significantly correlated. "Taste characteristics" changes and Catalpol5-HMF, digitalis glycosideA, digitalis glycosideDThere were significant correlations. According to the results of cluster analysis of "traits" and internal components, the steamed and sun dried Rehmannia glutinosa5The second is the "inflection point" of its processing properties reaching the fire standard.
3.1.3 Study on metabolites and markers during processing using metabolomics Technology The technology platform of metabolomics mainly includes nuclear magnetic resonance technology（NMR）, Qi-Mass spectrometry（GC-MS）And liquid-Mass spectrometry（LC-MS）Combined with multivariate statistics and other methods, it is more in line with the characteristics of the integrity of traditional Chinese medicine.
Liuetc.[60]adoptLC-MSObjective to quantitatively analyze the target sugars in raw Rehmannia glutinosa and wine stewed Rehmannia glutinosa. .Changetc.[61-62]useGC-MSCombined technology and principal component analysis（PCA）Statistical methods were used to analyze the effect of "nine steaming and nine drying" process of Rehmannia glutinosa1、5、9The secondary steaming and drying process and the metabolites of Rehmannia glutinosa were analyzed. The results showed that the amount of catalpol and stachyose gradually decreased with the increase of steaming times.PCAThe analysis results show that5After steaming and drying cycles, the results tended to be stable and the difference became smaller. after1H-NMR, Fourier Infrared-（FT-MS）Multivariate statistical analysis showed that the contents of Catalpol, raffinose and stachyose gradually decreased during processing, while the contents of monosaccharides (including galactose and glucose) gradually increased after processing, and the spectrum of metabolites gradually changed with the processing cycle. Differences in5.Zhouetc.[7,13]Based onUPLC-PDA-QTOF-MS/MSSecondary metabolite omics of non target traditional Chinese medicine based on IntegrationHPLC (C18)-UV、HPLC (NH2)-ELSDandHPGPC-ELSD.9After secondary steaming, the content of mirritoside decreased, catalpol and aucubin5. The content of phenylethanoid glycosides fluctuated during steaming. During the steaming process of Rehmannia glutinosa,5-HMFThe content first increased significantly and then decreased slightly. ago4After secondary steaming, the total oligosaccharide content showed a downward trend, and then tended to be stable. Stachyose, raffinose and sucrose1After secondary steaming, the content decreased sharply,5After secondary steaming, it was almost undetectable, while the content of melibiose and mannotriose increased sharply. With the extension of steaming time, the content tended to be stable, and the content of fructose and glucose also increased.6After secondary steaming, the overall quality of Rehmannia glutinosa tends to be stable and uniform. On this basis, from raw Rehmannia glutinosa and steam drying6Times and9From the chemical group of secondary Rehmannia glutinosa14Chemical markers, which were glycosides (digitalis glycosidesA、B、DAnd verbascoside), furanal derivatives（5-HMF.
3.2 Study on the efficacy and mechanism of Rehmannia glutinosa with different processing degrees
With the development of metabolomics, the overall quality of traditional Chinese Medicine/New progress has been made in efficiency evaluation methods. [63]。
There are studies[64]Integrating the effect metabolomics and classical pharmacodynamic indexes, the effect of different processing times on the pharmacodynamic effect of Radix Rehmanniae was clarified from the level of endogenous metabolic intervention. The blood deficiency rat model was induced by cyclophosphamide and acetylphenylhydrazine, and the model rats were respectively perfused with Rehmannia glutinosa in the blood deficiency state（RRR0）, steaming and drying6Secondary Rehmannia glutinosa l.var.subescens l.var.subescens l.var.subescens l.var.subescens l.var.subescens l.var.subescens l.var.subesce（PRR6）, steaming and drying9Secondary Rehmannia glutinosa l.var.subescens l.var.subescens l.var.subescens l.var.subescens l.var.subescens l.var.subescens l.var.subesce（PRR9）The results showed that the blood tonic intensity trend of the three wasPRR6＞PRR9＞RRR0。PRR9andRRR0Biomarkers that can significantly callback（P＜0.05）It mainly involves the interconversion of pentose and glucuronic acid（pentose andglucuronate interconversions）And sphingolipid metabolism（sphingolipid metabolism）Pathways, whilePRR6In addition to the above pathways, glyoxylate and dicarboxylic acid metabolism are also involved（glyoxylate and dicarboxylate metabolism）Pathways. However, in the rat model of kidney yin deficiency induced by levothyroxine sodium, the intensity trend of Nourishing Yin of the three wasPRR9＞PRR6＞RRR0。PRR6Biomarkers that can significantly callback（P＜0.05）Mainly involved in sphingolipid metabolic pathways,RRR0Mainly involved in the interconversion pathway of pentose and glucuronic acid, whilePRR9In addition to the above pathways, tryptophan metabolism is also involved（tryptophanmetabolism）Pathways. 9The secondary Rehmannia glutinosa had better effect of Nourishing Yin, while6The prepared rehmannia glutinosa after secondary steaming and sunburn has better blood tonic effect, and the possible metabolic pathways involved have been found, but the relevant research is still less, and other pharmacodynamic studies on different processing degrees of prepared rehmannia glutinosa have not been reported.
The processing process of Rehmannia glutinosa was dynamically monitored by means of infrared, liquid phase, nuclear magnetic resonance, mass spectrometry and metabolomics strategies5Times or6Times reached the inflection point, and then tended to be stable. The results of effector metabolomics showed that,9The prepared rehmannia glutinosa with secondary steaming and drying has better effect on Nourishing Yin,6The blood enriching effect of Rehmannia glutinosa after secondary steaming and sunburn is better, which provides a basis for selecting Rehmannia glutinosa with different processing degrees according to different medication purposes in clinic.
4 Conclusion and Prospect
The processing process of Rehmannia glutinosa prepared by the ancient method mostly requires "nine steams and nine basks", and the processing end point is judged according to the property and taste standard of "black as paint, sweet as Yi". With the help of modern research methods, relevant scholars have done a lot of research on the pharmacodynamic material basis of Rehmannia glutinosa. After processing, iridoids, phenylethanoid glycosides, sugars, furan aldehydes and other components have changed. The components with increased content are mainly polysaccharides, mannotriose5-HMFIt has pharmacological effects on blood, immunity, central nervous system and liver.
Prepared rehmannia glutinosa is often used in combination with other medicinal flavors to exert its efficacy[65]Common compounds include Liuwei Dihuang pill, Guilingji, Dingkun pill, etc. . In clinical practice, traditional Chinese medicine mostly exerts its curative effect by composition, and grasping the general compatibility law of common drug pairs of Radix Rehmanniae is conducive to better exert the efficacy of Radix Rehmanniae and further clarify the Guilingji[66]And so on. However, there are still few studies on the effect of different processed degrees of Rehmannia glutinosa on the drug pair and composition. For example, ancient prescriptions such as Guilingji mostly use the ancient method of nine steams and nine sunshines to ensure the excellent efficacy, which is the inheritance of the ancient processing technology, but its scientific connotation needs to be clarified. We can establish animal models, give Guilingji compound containing different processed times of Rehmannia glutinosa glutinosa, and combine the effect metabolomics to conduct an overall and comprehensive qualitative analysis of Rehmannia glutinosa glutinosa with different processed degrees/.
Traditional Chinese medicine (TCM) has the characteristics of "integrity, multi-target, and synergy", and only from the chemical level, the quality of TCM is evaluated/The effectiveness evaluation cannot scientifically interpret the complex system of traditional Chinese medicine and reflect the advantages of traditional Chinese medicine. Combined with the effect metabolomics, explore the contribution of different processed degrees of Rehmannia glutinosa to the classic composition, and the quality of Rehmannia glutinosa from the chemical, pharmacodynamic and other indicators/To further clarify the material basis of the efficacy of prepared rehmannia glutinosa, provide a scientific basis for objectively interpreting the scientific connotation of the traditional processing technology of Rehmannia glutinosa and optimizing the innovative process, and provide new ideas and methods for the inheritance and innovative research of the traditional processing technology of Chinese herbal pieces.
References (omitted)
Come Source: Du ; Feng, Wang Peiyi, Qin Xuemei Research progress of Rehmannia glutinosa effect evaluation based on pharmacodynamic material basis [j]. Chinese herbal medicine, 2019, 50 (6): 1477-1484