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Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced cytokine storms constitute the primary cause of coronavirus disease 19(COVID-19)progression,severity,criticality,and death.Gluco-corticoid and anti-cytokine therapies are frequently administered to treat COVID-19,but have limited clinical efficacy in severe and critical cases.Nevertheless,the weaknesses of these treatment modalities have prompted the development of anti-inflammatory therapy against this infection.We found that the broad-spectrum anti-inflammatory agent inosine downregulated proinflammatory interleukin(IL)-6,upregulated anti-inflammatory IL-10,and ameliorated acute inflammatory lung injury caused by mul-tiple infectious agents.Inosine significantly improved survival in mice infected with SARS-CoV-2.It indirectly impeded TANK-binding kinase 1(TBK1)phosphorylation by binding stimulator of interferon genes(STING)and glycogen synthase kinase-3β(GSK3β),inhibited the activation and nuclear trans-location of the downstream transcription factors interferon regulatory factor(IRF3)and nuclear factor kappa B(NF-κB),and downregulated IL-6 in the sera and lung tissues of mice infected with lipopoly-saccharide(LPS),H1N1,or SARS-CoV-2.Thus,inosine administration is feasible for clinical anti-inflammatory therapy against severe and critical COVID-19.Moreover,targeting TBK1 is a promising strategy for inhibiting cytokine storms and mitigating acute inflammatory lung injury induced by SARS-CoV-2 and other infectious agents.
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Objective To establish the method for the simultaneous determination of hypoxanthine, inosine, guanosine and adenosine in Dilong formula granules by HPLC and compare the fingerprints of Dilong formula granules from different manufacturers by HPLC chromatogram. Methods The contents of hypoxanthine, inosine, guanosine and adenosine were determined by Thermo AcclaimTM120C18 column (4.6 mm×250 mm 5 μm). The mobile phase was acetonitrile-water. Gradient elution with flow rate of 0.6 ml/min was used. Column temperature was 25 ℃. Detection wavelength was 254 nm. 10 batches of samples were tested. The HPLC chromatogram were compared and analyzed by using the similarity Evaluation system of chromatographic fingerprint of traditional Chinese Medicine (version 2012.130723). Results The linear ranges for the detection of hypoxanthine, inosine, guanosine and adenosine showed good linear relationships within their own ranges (r≥0.999 9). The average recoveries were 99.20%~102.98% with RSD of 0.26 %~0.71%. The contents of 4 components in 10 batches of samples were 0.740 0~4.457 4 mg/g, 2.132 3~7.805 0 mg/g, 0.325 4~1.596 1 mg/g, 0.537 2~2.222 9 mg/g respectively. The similarity between HPLC chromatogram and control fingerprints of Dilong formula granules from different manufacturers was greater than 0.91. Conclusion The method could be used to determine the contents of hypoxanthine, inosine, guanosine and adenosine in Dilong formula granule. HPLC fingerprints could be used to evaluation the quality in Dilong formula granule. The similarity of HPLC fingerprints from different manufacturer production of Dilong formula granule is high, but 4 contents in composition are difference.
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AIM: To investigate the effects of ginsenoside Rg1 injection combined with inosine tablets and vitamin B1 on serum brain-derived neurotrophic factor(BDNF), pituitary adenylate cyclase activating polypeptide(PACAP)and clinical efficacy in primary retinitis pigmentosa.METHODS: A total of 50 patients(100 eyes)with primary retinitis pigmentosa who admitted to the Department of Ophthalmology, the Second Affiliated Hospital of Hebei North University from August 2019 to March 2022 were selected as the research object. They were divided into the study group and the control group according to random number table, with 50 eyes in each group. Patients in the control group were treated with inosine tablets and vitamin B1, while patients in the study group were treated with ginsenoside Rg1 injection on the basis of the control group. The expression of BDNF and PACAP in serum, electroretinogram and spectral-domain optical coherence tomography(SD-OCT)were compared before and after treatment, and the retinal thickness(RT), mean deviation(MD), clinical efficacy and safety indexes were compared between the two groups.RESULTS: There were no differences in the MD of the two groups before treatment(t=1.670, P=0.098), while the MD of the study group was significantly lower than that of the control group after treatment(t=3.628, P<0.01). Before treatment, RT with a diameter of 1mm at the circle of macular fovea was compared between the two groups(t=0.108, P=0.914), it was significantly higher than that in the control group after treatment(t=6.125, P<0.01). Before treatment, there was no significant difference in the results of dark adaptation of electroretinogram between the two groups(all P>0.05). After treatment, the results of dark adaptation in the study group were significantly better than those in the control group(all P<0.01). Before treatment, there was no significant difference in the results of electroretinogram adaptation between the two groups(all P>0.05). After treatment, the results of electroretinogram adaptation in the study group were significantly better than those in the control group(all P<0.01). There was no significant difference in BDNF and PACAP between the two groups before treatment(all P>0.05). BDNF and PACAP in the study group were higher than those of the control group after treatment(all P<0.01). After treatment, no adverse reactions were observed in both groups.CONCLUSION: The treatment of patients with primary retinitis pigmentosa with ginsenoside will improve the retinal function and promote the prognosis of the disease by regulating the expression of BDNF and PACAP, and it is highly safe.
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Cryptosporidiosis is a neglected tropical disease caused by the protozoan parasite Cryptosporidium parvum. Limited therapeutic options, limitation in in vitro parasite culture, and lack of a reliable animal model of parasite for replication of in vivo life cycle and drug testing demand alternative methods for drug development. The in silico methods of drug discovery prove a crucial process in such conditions.Recent research reported a limited number of small molecules for drug development. Purine nucleotide biosynthesis in Cryptosporidium species is dependent on the IMPDH (CpIMPDH) enzyme, so distortion of parasite IMPDH has been pursued as a compelling strategy for curbing Cryptosporidium infection due to its different kinetics from the host enzyme. Our study's primary aim was to discover novel ligand molecules with noticeable activity against Cryptosporidium parvum IMPDH. For this purpose, we selected 18 previously discovered ligands to understand the interaction feature between ligand and receptor, and their shape and electronic features are employed as a template for shape-based virtual screening of the ZINC database (drug-like subset) search approach via Schrodinger-2019 (Maestro 11.9). The obtained hits were subsequently subjected to structure-based screening, quantum polarized ligand docking (QPLD), and molecular dynamics simulations to fetch potential small molecules with the highest binding affinity for CpIMPDH protein. Further ligand binding energy and pharmacokinetic analysis were also taken into consideration as filtering criteria for selecting the most promising drug-like compounds. On this experimentation analysis, three top-ranked (ZINC24855054, ZINC58171263, and ZINC08000072) molecules were found to have appropriate pharmacokinetic properties along with surpassing in silico inhibitory potential towards the CpIMPDH compared to known inhibitors. The molecular docking and molecular dynamics simulation analysis results satisfactorily confirmed the inhibitory action. Therefore, these new scaffolds deduced by the presented computational methodology could recommend lead molecules for designing promising anti-cryptosporidial drugs targeting CpIMPDH protein.
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Depression was a complex and difficult to regulate disease, which was closely related to purinergic system and purine metabolism disorder. Although there had been studies to improve depression by regulating purinergic system, the mechanism of action was complex and needed to be sorted out. Recently, a large number of studies had found that the addition of exogenous purine metabolites adenosine, inosine and guanosine had a significant antidepressant effect, indicating that regulating the level of purine substances in purine metabolism could also improve depression, which was of great significance to the further study of the pathogenesis and treatment of depression. In view of this, this study reviewed the relationship between purinergic system or purine metabolism and depression, in order to provide a reference for the further study of the pathogenesis of depression.
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An eco-friendly and fast HPLC method was developed for the determination of adenosine, inosine, guanosine and uridine in Cordyceps and related products (fermented mycelia of Hirsutella sinensis andPaecilomyces hepiali). The sample was ultrasonically extracted using 0.5% phosphoric acid solutions for 2.5 min. Sample separation was performed on a Poroshell SB-Aq column (50 mm × 4.6 mm, 2.7 μm) using eco-friendly mobile phase consisting of formic acid and ammonium formate aqueous solution at a flow rate of 1.0 mL·min
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Adenosine , Chromatography, High Pressure Liquid , Cordyceps , NucleosidesABSTRACT
Objective@#To investigate the change in expression of anti-senescence marker protein calmodulin (RGN) in liver tissues of rats with immune hepatic fibrosis, and to observe the effect of compound glutathione inosine injection (CGII) on it.@*Methods@#Rat liver fibrosis model was induced by intraperitoneal injection of porcine serum, and CGII intervention was administered at the appropriate time. Rat liver tissues were stained with HE and Masson. RGN and protein expression at mRNA in liver tissues was detected by fluorescence quantitative PCR and immunohistochemistry. One-way Anova was used for measurement data. LDS test was used for two-way comparison, and pathological semi-quantitative results were analyzed by rank-sum test.@*Results@#The relative expression of RGN mRNA and protein in liver tissue of fibrotic rats was 82.23 ± 15.21 and 12.52 ± 3.23, respectively, which were significantly lower than that of normal rats 176.39 ± 11.35 and 59.23 ± 9.13 (P < 0.01). The degree of liver fibrosis in fibrotic rats after CGII intervention was significantly lower than fibrotic rats. The relative expression of RGN mRNA and protein in the intervention group was 168.78 ± 21.31 and 46.42 ± 4.71, respectively, which were significantly higher than fibrosis and spontaneous recovery group. The difference was statistically significant (P < 0.01). The relative expression of RGN mRNA and protein in the spontaneous recovery group was 86.23 ± 17.16 and 14.34 ± 5.16, which was higher than model group. The difference was not statistically significant (P > 0.05).@*Conclusion@#The expression of RGN in liver tissue of rats with hepatic fibrosis induced by porcine serum is decreased, while the expression of RGN increases with the decrease of fibrosis after CGII intervention, suggesting that the protein may play an important role in the development of liver fibrosis.
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OBJECTIVE： To provide reference for improving the quality standard of Pheretima. METHODS： The contents of hypoxanthine and inosine in medicinal material samples were determined by HPLC. HPLC fingerprint of Pheretima was established according to “Similarity evaluation system for TCM chromatogramtic fingerprint” （2012 edition） software， and similarity evaluation was conducted. The determination was performed on Purospher STAR RP-18 endcapped with mobile phase consisted of methanol-water （gradient elution） at the flow rate of 1 mL/min. The detection wavelength was 248 nm， and the column temperature was set at 30 ℃. The sample size was 20 μL. RESULTS： The results of methodological investigation of content determination showed that the linear range of hypoxanthine and inosine were 1.58-31.6 μg/mL （r＝0.999 9）， 5.52-110.4 μg/mL（r＝0.999 8）， respectively. limits of quantify were 0.316， 0.552 μg/mL， respectively； limits of detection were 0.158， 0.110 μg/mL， respectively； RSDs of precision， stability （24 h） and repeatability tests were all less than 2.0％ （n＝6）. Average recovery rates were 103.0％ （RSD＝1.7％， n＝6） and 101.2％ （RSD＝1.2％， n＝6）， respectively. HPLC fingerprint for 15 batches of samples were established， and 8 common peaks were identified. The similarity of HPLC fingerprint of 14 batches of sample with control fingerprint R was higher than 0.900. CONCLUSIONS： The established method for content determination of hypoxanthine and inosine and HPLC fingerprint of Pheretima are simple， accurate and reproducible， and can be used for quality control of Pheretima.
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The TLC method was established for identification of Holotricha diomphalia larvae and the HPLC method was used to determine the content of inosine and guanosine in H. diomphalia larvae. The HPLC analysis was performed on a Waters HSS T3（4.6 mm×250 mm, 5 μm） column of with mobile phase consisting of acetonitrile (A) and 0.08% trifluoroacetic acid (B) in gradient elution. The detection wavelength was 260 nm. The flow rate was 1.0 mL·min⁻¹. The column temperature was 30 °C. As a result, TLC identification method had a good reproducibility and highly specificity. The linear equations of inosine and guanosine were in good linear range (r>0.999 8). The average recovery of inosine and guanosine was 96.53% (RSD=1.6%), 99.71% (RSD=2.7%). The method is simple, accurate and reproducible, which can provide a basis for quality standard improvement H. diomphalia larvae.
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Objective At present,there is still a lack of effective means for the treatment of diabetic cystopathy,and to find natural antioxidants for this purpose has become a hot spot in research. This study is to investigate the protective effect of inosine on the bladder of diabetic rats and its antioxidative stress mechanisms. Methods A total of 60 adult male Sprague-Dawley rats were ran-domly divided into three groups of equal number:normal control,diabetes mellitus(DM) model control,and inosine intervention. The DM model was made by intraperitoneal injection of streptozotocin at 60 mg/kg. The DM model controls were injected with saline while the model rats in the intervention group with inosine, all at 75 mg/kg, ip,bid. After 4 and 8 weeks of treatment, the bladder tissues were collected from the rats for examination of the structural changes by HE staining,determination of the expressions of c-kit and nerve growth factor (NGF) by immunofluorescence assay, and observation of the ultrastructure of the bladder tissue under the electron microscope,de-tection of the cell apoptosis by TUNEL,and measurement of the con-tents of malondialdehyde (MDA),superoxide dismutase (SOD),and glutathione (GSH). Results HE staining indicated signifi-cant mucosal hyperplasia, disordered arrangement, loose structure, fracture, expanded intervals and collagen fiber filling of muscle bundles,muscular atrophy,lymphocytes infiltration,vascular hyperplasia and congestion,and few muscle bundles,while electron mi-croscopy manifested disordered arrangement, interrupted connection, mitochondrial vacuolation in muscular and interstitial cells, shrinkage of nuclear membrane,disappearance of nucleoli,and irregular chromatin margination and condensation in the bladder tissues of the DM rat models. Immunofluorescence assay showed that the signals of c-kit and NGF were reduced in the DM models as compared with those in the normal controls. After 4 and 8 weeks of intervention,the cell apoptosis rate was significantly higher in the DM model control ([1.68±3.04]% and [10.51±0.90]%) and inosine-treated rats ([7.00±1.72]% and [7.24±1.66]%) than in the normal controls ([4.65±3.04]% and[5.48±2.00]%),but remarkably lower in the inosine-treated than in the DM model controls(P<0.01). The contents of SOD and GSH were increased(P<0.05) while that of MDA decreased markedly in the DM models(P<0.05),but the former decreased (P<0.05) while the latter increased significantly in the inosine intervention group as compared with the DM model control group (P<0.05). At 8 weeks,the contents of SOD and GSH were remarkably lower in the DM model than in the normal con-trols (P<0.01),while that of MDA markedly higher than in both the normal control and inosine intervention groups (P<0.01). The wet weight of the bladder was significantly increased in the DM model and inosine intervention groups in comparison with that of the nor-mal controls(P<0.01). Conclusion Oxidative stress plays an important role in the development and progression of diabetic cystopa-thy. Inosine can protect the bladder structure and function of the DM rat by reducing oxidative stress and injury to the bladder tissue.
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AIM To establish the HPLC fingerprints of Kangfuxin Liquid (extract of Periplaneta americana L.) and to determine the contents of six constituents.METHODS The analysis of this drug was performed on a TOSOH TSK-GEL ODS column (250 mm × 4.6 mm,5 μm),with the mobile phase comprising of acetonitrile-water (containing 0.07％ acetic acid) flowing at 1.0 mL/min in a gradient elution manner,and the detection wavelength was set at 280 nm.RESULTS There were twenty-four common peaks in the fingerprints of ten batches of samples (Ⅰ-Ⅹ) with the similarities of 0.932-0.993 (except for sample Ⅰ).Uracil,hypoxanthine,xanthine,inosine,protocatechuic acid and Cyclo (Gly-Tyr) showed good linear relationships within the ranges of 3.460-173.0,3.960-198.0,3.596-179.8,1.338-66.9,3.672-183.6 and 3.552-177.6 μg/mL,whose average recoveries (RSDS) were99.8％ (2.65％),98.0％ (2.55％),99.7％ (1.59％),100.7％ (2.80％),102.0％ (2.09％) and 99.6％ (1.88％),respectively.CONCLUSION This accurate,stable and simple method can be used for the quality control of Kangfuxin Liquid.
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OBJECTIVE: To establish a quantitative method for determining the contents of uracil, cytidine, hypoxanthine, xanthine, uridine, inosine, and guanosine in Holotrichia diomphalia Larvae by HPLC. METHODS: The HPLC analysis was performed on Waters HSS T3 column(4.6 mm×250 mm, 5 μm). The mobile phase was composed of acetonitrile(A) and water(B), and gradient elution was carried out. The flow rate was 1.0 mL•min-1. The column temperature was maintained at 30 ℃. The detection wavelength was 260 nm. RESULTS: The correlation coefficients of the seven components ranged from 0.999 1 to 1.000 0. The average recovery rates(n=6) were between 91.2% and 97.4%, and the RSDs were between 1.5% and 2.3%. CONCLUSION: The proposed method is simple, accurate and reliable, thus providing basis for comprehensive quality control of Holotrichia diomphalia Larvae.
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Aim To establish a novel acute hyperuricemia mouse model and apply it to evaluate the hyporucicemia effects of Ulodesine, a purine nucleoside phosphorylase(PNP) inhibitor.Methods The mice were intraperitoneal injected inosine and subcutaneous injected Oteracil potassium to induce accumulation of uric acid, and the animal blood was collected from eyeball or vena angularis in different time points.The levels of serum uric acid were measured and determined to test whether the acute hyperuricemia mouse model were successful or not.In order to verify the hyperuricemia seen in the model was associated with the accumulation of inosine, which was converted to uric acid by action of PNP,hyporucicemia effects of Ulodesine, a PNP inhibitor, was assessed in an enzyme assay and confirmed by using the newly established model.Result Accumulation of uric acid in the blood of mouse models was observed by combined injections of intraperitoneal 200 mg·kg-1 inosine and subcutaneous 200 mg·kg-1 Oteracil potassium respectively after 1.5 h.The enzyme assay indicated that Ulodesine was a potently PNP inhibitor with IC50 of 2.293 nmol·L-1.IV injection of Ulodesine eliminated uric acid accumulations in blood of the mouse model, which was expected as the in vivo action of Ulodesine.Conclusions A novel acute hyperuricemia mouse model is established.This is a relatively easy and more effective protocol to generate the hyperuricemia in mice, which will be a useful platform to assess the anti-hyperuricemia activity of PNP-target drugs in vivo.
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Objective:To study the compatibility and stability of coenzyme A for injection, adenosine disodium triphosphate and inosine injection. Methods:By simulating the clinical medication, the three drugs and 5% glucose injection were mixed together. The contents and relative substances of coenzyme A, adenosine disodium triphosphate and inosine were measured by HPLC. The changes in appearance, pH and insoluble particles were observed or tested at ambient temperature. Results:The mixed solution showed no signifi-cant changes in appearance, pH, number of insoluble particles, contents and relative substances of coenzyme A, adenosine disodium triphosphate and inosine in 4 h, while the mixed solution became turbid and the pH, number of insoluble particles and contents of the three drugs showed significant changes after 24-h storage. Conclusion:The mixed solution of coenzyme A for injection, adenosine dis-odium triphosphate and inosine injection in 5% glucose injection should be used up in 4 h at ambient temperature.
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Inosine 5'-monophosphate dehydrogenase (IMPDH) is a rate-limiting enzyme in de novo biosynthesis of guanine and plays an important role in cell proliferation. In clinic, IMPDH inhibitors are mainly used in fields of anticancer, antiviral, anti-parasitic, and immunosuppressive chemotherapy. However, since there are usually great inter-and intra-individual variability between drug concentration and clinical effect of IMPDH inhibitors, the enzyme activity of IMPDH may be applied as a specific biomarker and combined with the pharmacokinetics (PK) monitoring to improve efficacy and safety of IMPDH inhibitors. This review aims to discuss the assay of IMPDH activity measurement and its clinical application in recent years and provide valuable insights and theoretical basis for the development of IMPDH inhibitors' pharmacodynamics monitoring.
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A new method was developed for the separation and determination of inosine monophosphate (IMP) by ion chromatography (IC) with suppressed conductivity detection. Separation was achieved on an anion-exchange column Ionpac AS11-HC of high capacity within a short time. 30 mmol/L KOH produced by an EGC-KOH eluent generator was used for isocratic elution. No interferences existed between the seven common inorganic anions and IMP. Under the optimum conditions, the linear range of the calibration curve for IMP was 1. 0-200 mg/L, with correlation coefficient ( R2 ) of 0. 999. The relative standard deviations (RSDs) for retention time, peak height and peak area of IMP were 0. 16%, 0. 94% and 0. 86%, respectively, indicating good reproducibility of the method. The method was successfully applied to the determination of IMP in meat products, with spiked recovery ranging from 86. 0% to 110. 0%. This simple, accurate and reliable method could be served as a rapid and effective analytical tool for meat flavoring research.
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Objective: To develop a rapid high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) method for the simultaneous determination of six polar compounds in Ophiocordyceps sinensis. Methods: A poroshell SB Aq column (50 mm × 4.6 mm, 2.7 μm) and gradient elution were used; The detection wavelength of compounds was set at 260 nm. The chromatographic peaks of the six investigated compounds in sample were identified by comparing their retention times with reference compounds. Results: All calibration curves showed good linearity (r > 0.999) within the tested ranges. The intra- and inter-day precisions of the six analytes were less than 0.8% and 2.1%, respectively, and the recoveries of the six analytes were between 95% and 103%. The validated method was successfully applied to the determination of six polar compounds in O. sinensis samples. Conclusion: The poroshell SB Aq column is suitable for the rapid analysis of polar components in Chinese materia medica on conventional HPLC system and the developed HPLC method is also helpful to the quality control of O. sinensis. © 2014 Tianjin Press of Chinese Herbal Medicines.
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Objective: To investigate the influence of different processing methods on the contents of nucleosides in Pseudostellariae Radix (PR). Methods: Q-TRAP-LC-MS/MS method was applied for the analysis on 13 kinds of nucleosides in PR with different processing methods. Results: The contents of cytidine, uridine, inosine, guanosine, and thymidine were higher in PR. The different processing methods of PR had certain influence on the contents of nucleosides. The amount of nucleosides in PR by oven drying was higher than that by drying in the sun. Conclusion: The paper investigates the influence of processing methods on chemical composition in PR, and provides the basis for establishing reasonable processing technology.
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Objective: To establish a UPLC-MS/MS method for the simultaneous determination of nine kinds of nucleosides in Spirodelae Herba, and analyze and investigate the difference of nucleosides ingredients in samples from 13 habitats. Methods: The determination was performed on the Waters XbridgeTM Amide-C18 (150 mm × 4.6 mm, 3.5 μm), the 0.1% formic acid-water (A) and 0.1% acetonitrile-water (B) in gradient elution as mobile phase. The flow rate was 0.5 mL/min. The column temperature was 30 ℃. MS instrument was equipped with ESI+ ion source. Gaining the extracted ion chromatograms, then the peak area for quantitative, principal component analysis (PCA), and hierarchical clustering analysis (HCA) were used to comprehensive evaluation. Results: All nine kinds of nucleoside showed good linearity (r ≥ 0.998 9). The RSD of the precision, repeatability, and stability tests were less than 3.5%. The average recovery rates were in the range of 94.4%-101.9%, RSD were in the range of 1.73% - 3.58%. There are differences in the composition and content from different habitats. The content of 2'-deoxyuridine and 2'-deoxyinosine in the lower levels, cytosine was the lowest, while the contents of uridine, inosine, and xanthine were in higher levels. The largest content was in Spirodelae Herba from Huangshan, Anhui province. Conclusion: The method for the simultaneous determination of the nine kinds of nucleosides is simple, accurate, and reproducible, that will provide the basis for the formulation of herbs Spirodelae Herba for quality control standards.
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OBJECTIVE: To establish a QTRAP UPLC-MS/MS method for simultaneous determination of thirteen nucleosides and nucleobases in Pseudostellariae Radix, and analyze their dynamic changes at different periods. METHODS: The separation was carried out on a Waters Atlantis T3 column (2.1 mm × 150 mm, 3 μm)eluted by a mobile phase of 5 mmol · mL-1 of ammonium acetate (B)-methanol(A) at a flow rate of 0.4 mL · min-1. The elution program is as follows. 0 -4.5 min, 3% -4% A; 4.5-8 min, 4% -18% A; 8 -10 min, 18%A; 10 -10.1 min, 18% -3% A; 10.1 -13 min, 3%A. The target compounds were analyzed by the positive ion multiple reaction monitoring (MRM) mode. RESULTS: The calibration curves of the 13 nucleosides and nucleobases showed good linearity (r >0.991 0) in the ranges of the tested concentrations, and the average recoveries were between 96.46% - 105.07%. The contents of cytidine, uridine, inosine, guanosine, and thymidine in Pseudostellariae Radix harvested at different periods showed some differences, and the contents were higher in mid-June. CONCLUSION: The method is simple, sensitive, accurate and credible, and provides the basis for exploring the quality forming mechanism of Pseudostellariae Radix medicinal materials and the suitable harvest time.