1.Establishment of a quantitative method for GC analysis of polyoxyethylene (35) castor oil in microemulsion extracts.
Yan-Jing WANG ; Yi CHENG ; Ze-Min OU ; Yao ZHANG ; Lin YAN ; Yan TONG ; Jin-Yu WANG ; De-Wen LIU
China Journal of Chinese Materia Medica 2023;48(22):6075-6081
With the continuous exploration of microemulsions as solvents for traditional Chinese medicine extraction, polyoxyethy-lene(35) castor oil(CrEL), a commonly used surfactant, is being utilized by researchers. However, the problem of detecting residues of this surfactant in microemulsion extracts has greatly hampered the further development of microemulsion solvents. Based on the chemical structures of the components in CrEL and the content determination method of castor oil in the 2020 edition of the Chinese Pharmacopoeia(Vol. Ⅳ), this study employed gas chromatography(GC) and single-factor experiments to optimize the preparation method of methyl ricinoleate from CrEL. The conversion coefficient between the two was validated, and the optimal sample preparation method was used to process microemulsion extracts of Zexie Decoction from three batches. The content of methyl ricinoleate generated was determined, and the content of CrEL in the microemulsion extracts of Zexie Decoction was calculated using the above conversion coefficient. The results showed that the optimal preparation method for CrEL was determined. Specifically, 10 mL of 1 mol·L~(-1) KOH-methanol solution was heated at 60 ℃ for 15 min in a water bath. Subsequently, 10 mL of boron trifluoride etherate-methanol(1∶3) solution was heated at 60 ℃ for 15 min in a water bath, followed by extraction with n-hexane twice. CrEL could stably produce 20.84% methyl ricinoleate. According to this conversion coefficient, the average mass concentration of CrEL in the three batches of Zexie Decoction microemulsion extracts was 11.94 mg·mL~(-1), which was not significantly different from the CrEL mass concentration of 11.57 mg·mL~(-1) during microemulsion formulation, indicating that the established content determination method of this study was highly accurate, sensitive, and repeatable. It can be used for subsequent research on microemulsion extracts of Zexie Decoction and provide a reference for quality control of other drug formulations containing CrEL.
Polyethylene Glycols/chemistry*
;
Castor Oil
;
Methanol
;
Surface-Active Agents/chemistry*
;
Solvents
;
Water/chemistry*
;
Emulsions/chemistry*
2.Chemical constituents in different parts of Ixeris sonchifolia based on UPLC-LTQ-Orbitrap-MS~n.
Yi-Ran REN ; Yuan-Yuan ZHAO ; Zhao-Wei LIU ; Zhen-Qing LIU ; Ying LIU
China Journal of Chinese Materia Medica 2023;48(2):430-442
The chemical constituents in stem leaf, root, and flower of Ixeris sonchifolia were identified by the ultra performance li-quid chromatography coupled with linear ion trap quadrupole-orbitrap mass spectrometry(UPLC-LTQ-Orbitrap-MS~n). The separation was performed on an Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 μm) with a mobile phase of water(containing 0.1% formic acid, A)-acetonitrile(B) with gradient elution. With electrospray ionization source, the data of 70% methanol extract from stem leaf, root and flower of I. sonchifolia were collected by high-resolution full-scan Fourier transform spectroscopy, data dependent acquisition, precursor ion scan, and selected ion monitoring in the negative and positive ion modes. The compounds were identified based on accurate molecular weight, retention time, fragment ions, comparison with reference standard, Clog P and references. A total of 131 compounds were identified from the 70% methanol extract of I. sonchifolia, including nucleosides, flavonoids, organic acids, terpenoids, and phenylpropanoids, and 119, 110, and 126 compounds were identified from the stem leaf, root and flower of I. sonchifolia, respectively. In addition, isorhamnetin, isorhamnetin-7-O-sambubioside and caffeylshikimic acid were discovered from I. sonchifolia for the first time. This study comprehensively analyzed and compared the chemical constituents in different parts of I. sonchifolia, which facilitated the discovery of effective substances and the development and application of medicinal material resources of I. sonchifolia.
Drugs, Chinese Herbal/chemistry*
;
Methanol
;
Chromatography, High Pressure Liquid/methods*
;
Mass Spectrometry
;
Asteraceae
3.Advances in biotransformation of methanol into chemicals.
Kang LIU ; Yangyi QIAO ; Shangjie ZHANG ; Feng GUO ; Jiangfeng MA ; Fengxue XIN ; Wenming ZHANG ; Min JIANG
Chinese Journal of Biotechnology 2023;39(6):2430-2448
Methanol has become an attractive substrate for the biomanufacturing industry due to its abundant supply and low cost. The biotransformation of methanol to value-added chemicals using microbial cell factories has the advantages of green process, mild conditions and diversified products. These advantages may expand the product chain based on methanol and alleviate the current problem of biomanufacturing, which is competing with people for food. Elucidating the pathways involving methanol oxidation, formaldehyde assimilation and dissimilation in different natural methylotrophs is essential for subsequent genetic engineering modification, and is more conducive to the construction of novel non-natural methylotrophs. This review discusses the current status of research on methanol metabolic pathways in methylotrophs, and presents recent advances and challenges in natural and synthetic methylotrophs and their applications in methanol bioconversion.
Humans
;
Methanol/metabolism*
;
Metabolic Engineering
;
Metabolic Networks and Pathways
;
Biotransformation
4.Detection of Carbamazepine and Its Metabolites in Blood Samples by LC-MS/MS.
Hai-Yan CUI ; Chen-Xi LÜ ; Yan-Hua SHI ; Ni YUAN ; Jia-Hao LIANG ; Quan AN ; Zhong-Yuan GUO ; Ke-Ming YUN
Journal of Forensic Medicine 2023;39(1):34-39
OBJECTIVES:
To establish a method for the detection of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).
METHODS:
The blood samples were treated with 1-butyl-3-methylimidazolium hexafluorophosphate as an extraction solvent. The samples were extracted by ultrasound-assisted extraction and separated by ZORBAX Eclipse Plus C18, 95Å column. The mobile phase A aqueous solution containing 0.1% formic acid and 10 mmol/L ammonium acetate, and mobile phase B mixed organic solvent containing acetonitrile/methanol (Vacetonitrile∶Vmethanol=2∶3) were used for gradient elution at the flow rate of 1.00 mL/min. An electrospray ion source in positive mode was used for detection in the multiple reaction monitoring.
RESULTS:
The linearities of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples were good within the corresponding range, with correlation coefficients (r) greater than 0.995 6. The limits of detection were 3.00, 0.40 and 1.30 ng/mL, respectively. The limit of quantitation were 8.00, 1.00 and 5.00 ng/mL, respectively. The extraction recoveries ranged from 76.00% to 106.44%. The relative standard deviations of the intra-day and inter-day precisions were less than 16%. Carbamazepine and its main metabolite 10,11-dihydro-10,11-epoxycarbamazepine were detected in blood samples of death cases with a mass concentration of 2.71 μg/mL and 252.14 ng/mL, respectively.
CONCLUSIONS
This method has high sensitivity and good selectivity, which is suitable for the detection of carbamazepine and its metabolites in blood samples, and can be used for carbamazepine-related forensic identifications.
Chromatography, Liquid/methods*
;
Tandem Mass Spectrometry
;
Methanol
;
Carbamazepine/analysis*
;
Benzodiazepines/analysis*
;
Solvents
;
Chromatography, High Pressure Liquid
;
Solid Phase Extraction
5.Rapid determination of acetaminophen in plasma by LC-MS/MS.
Yan YU ; Hui Ling LI ; Jing MA ; Bo ZHOU ; Fang DONG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2023;41(5):364-366
Objective: To establish a method for the rapid determination of acetaminophen (APAP) in human plasma by LC-MS/MS. Methods: The plasma samples were extracted by methanol and acetonitrile (1: 1) and purified directly. C(18) column was used for sample separation. The mobile phase were methanol (5 mmol/L ammonium acetate) and water (5 mmol/L ammonium acetate). Samples were analyzed by LC MS/MS with the electrospray ionization multi reaction monitoring (MRM) mode. Results: The calibration curves of APAP was linear in the concentration range of 0~10 mg/L, the correlation coefficient (r) was greater than 0.999 0. The relative standard deviation within and between batches was less than 10%. The recovery rate were 96.81%~101.7%. The detection limit of the method was 0.1 μg/L and the lower limit of quantification was 0.3 μg/L. Conclusion: This method has strong specificity, high sensitivity and reliable determination results. It is suitable for the rapid analysis of clinical plasma samples.
Humans
;
Chromatography, Liquid/methods*
;
Acetaminophen
;
Tandem Mass Spectrometry/methods*
;
Methanol
;
Chromatography, High Pressure Liquid/methods*
6.Determination of 22 phospholipids in serum by ultra performance liquid chromatography-tandem mass spectrometry.
Wen Rong WANG ; Fang Da PENG ; Tao LI ; Chun Guang DING ; Huan Qiang WANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2023;41(5):366-371
Objective: To establish ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the determination of 22 phospholipids in serum. Methods: In September 2022, Using synthetic non endogenous phospholipids as internal standard, phospholipids in serum were extracted by methanol-dichloromethane (2∶1, V/V) protein precipitation method. Chromatographic separation was achieved on an ACQUITY UPLC BEH shield RP18 column, and the mobile phase was methanol/water (5∶95, V/V) containing 10 mM ammonium formate and methanol. Detection was performed in multiple reaction monitoring mode with ion mode switching. And the method was applied by analyzing phospholipids in the serum of coal workers' pneumoconiosis patients. Results: The 22 phospholipids showed good linear relationships in their respective concentration ranges and the correlation coefficients were higher than 0.990. The spiked recoveries of the 22 phospholipids were 81.03%-121.63% at the three spiked levels. The intra-assay were less than 14.52%, and the inter-assay were less than 15.00%. Conclusion: The method with the advantages of simplicity, stability and high sensitivity, and it can be used for the analysis of phospholipids in serum.
Humans
;
Chromatography, Liquid
;
Chromatography, High Pressure Liquid/methods*
;
Tandem Mass Spectrometry/methods*
;
Phospholipids
;
Methanol
7.Clinical features and follow-up outcomes of optic nerve injury induced by acute methanol poisoning.
Chinese Journal of Industrial Hygiene and Occupational Diseases 2022;40(5):366-369
Acute methanol poisoning harms the optic nerve and central nervous system, can cause irreversible damage, even coma or death in severe cases. This article reported four cases of methanol poisoning. 3 patients mistakenly ingested industrial alcohol containing methanol, the most serious patient suffered from coma, vision loss and other symptoms, the blood methanol concentration was 869.3 μg/ml. Another patient was poisoning caused by inhalation of methanol, with symptoms such as total blindness in the right eye and decreased visual acuity in the left eye. After active supportive treatment, 2 patients had partial recovery of visual acuity, and 2 patients had no sequelae. This article discussed the clinical features, treatment and prognosis of optic nerve damage caused by methanol poisoning, in order to raise awareness of this disease.
Coma
;
Follow-Up Studies
;
Humans
;
Methanol
;
Optic Nerve
;
Optic Nerve Injuries
;
Poisoning/therapy*
8.Identification of the New Psychoactive Substance Eutylone.
Qian-Ya DENG ; Wen-Juan SUN ; Si-Yang HE ; Kua-Dou WANG ; Yong-Sheng CHEN ; Wei WANG ; Chen LIANG
Journal of Forensic Medicine 2022;38(4):473-477
OBJECTIVES:
To establish a method to identify unknown sample based on the combined use of Fourier transform infrared spectroscopy (FTIR), gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry (UPLC-LTQ-Orbitrap MS) and 1H-nuclear magnetic resonance spectroscopy (1H-NMR) technique.
METHODS:
The unknown sample was directly analyzed by FTIR. The unknown sample was dissolved in methanol solution containing internal standard SKF525A and the supernatant was detected by GC-QTOF-MS and UPLC-LTQ-Orbitrap MS. The unknown sample was dissolved in methanol-d4 solution for structural analysis of 1H-NMR.
RESULTS:
The characteristic absorption peaks of FTIR spectra obtained from unknown sample were 1 682 (C=O bond), 1 503, 1 488, 1 436, 1 363, 1 256, 1 092, 1 035, 935, 840 and 800 cm-1, the characteristic fragment ions (m/z) of GC-QTOF-MS were 86.096 4 (base peak), 58.065 1, 149.023 5, 121.028 6 and 65.038 6, the accurate mass [M+H]+ detected by UPLC-LTQ-Orbitrap MS was 236.127 7. The sample was identified as synthetic cathinone new psychoactive substance Eutylone by 1H-NMR.
CONCLUSIONS
The method established in this study can be used for structural confirmation of Eutylone.
Methanol
;
Chromatography, High Pressure Liquid/methods*
;
Mass Spectrometry
;
Gas Chromatography-Mass Spectrometry/methods*
;
Magnetic Resonance Spectroscopy
9.Expression, purification and bioactivity analysis of a recombinant fusion protein rHSA-hFGF21 in Pichia pastoris.
Tiantian HUANG ; Jianying QI ; Ganggang YANG ; Xianlong YE
Chinese Journal of Biotechnology 2022;38(9):3419-3432
Human fibroblast growth factor 21 (hFGF21) has become a candidate drug for regulating blood glucose and lipid metabolism. The poor stability and short half-life of hFGF21 resulted in low target tissue availability, which hampers its clinical application. In this study, the hFGF21 was fused with a recombinant human serum albumin (HSA), and the resulted fusion protein rHSA-hFGF21 was expressed in Pichia pastoris. After codon optimization, the recombinant gene fragment rHSA-hFGF21 was inserted into two different vectors (pPIC9k and pPICZαA) and transformed into three different strains (X33, GS115 and SMD1168), respectively. We investigated the rHSA-hFGF21 expression levels in three different strains and screened an engineered strain X33-pPIC9K-rHSA-hFGF21 with the highest expression level. To improve the production efficiency of rHSA-hFGF21, we optimized the shake flask fermentation conditions, such as the OD value, methanol concentration and induction time. After purification by hollow fiber membrane separation, Blue affinity chromatography and Q ion exchange chromatography, the purity of the rHSA-hFGF21 protein obtained was 98.18%. Compared to hFGF21, the biostabilities of rHSA-hFGF21, including their resistance to temperature and trypsinization were significantly enhanced, and its plasma half-life was extended by about 27.6 times. Moreover, the fusion protein rHSA-hFGF21 at medium and high concentration showed a better ability to promote glucose uptake after 24 h of stimulation in vitro. In vivo animal studies showed that rHSA-hFGF21 exhibited a better long-term hypoglycemic effect than hFGF21 in type 2 diabetic mice. Our results demonstrated a small-scale production of rHSA-hFGF21, which is important for large-scale production and clinical application in the future.
Animals
;
Blood Glucose/metabolism*
;
Diabetes Mellitus, Experimental
;
Fibroblast Growth Factors
;
Humans
;
Hypoglycemic Agents/metabolism*
;
Methanol/metabolism*
;
Mice
;
Pichia/metabolism*
;
Recombinant Fusion Proteins
;
Recombinant Proteins/metabolism*
;
Saccharomycetales
;
Serum Albumin/metabolism*
;
Serum Albumin, Human/metabolism*
10.Effect of origin, tree age, and harvesting time on content of flavonoids and terpene lactones in Ginkgo Folium.
Fu-Juan SHI ; Chao-Jie YANG ; Xiu-Fen CHEN ; Mi-Ji-Ti MAIHELIYA ; Miao-Miao HUANG ; Xue-Jiao WEI ; Kun WANG ; Chun-Sheng LIU ; Yao-Jun YANG
China Journal of Chinese Materia Medica 2022;47(15):4055-4065
The content of total flavonol glycosides in Ginkgo Folium in the planting bases was determined by high performance liquid chromatography(HPLC).The samples were extracted by reflux with methanol-25% hydrochloric acid.The HPLC conditions were as follows: Agilent ZORBAX SB-C_(18) column(4.6 mm×250 mm, 5 μm), isocratic elution with mobile phase of 0.4% phosphoric acid solution-methanol(45∶55), flow rate of 1 mL·min~(-1), column temperature of 30 ℃, detection wavelength of 360 nm, and injection vo-lume of 10 μL.A method for the determination of terpene lactones in Ginkgo Folium was established based on ultra-high performance liquid chromatograph-triple-quadrupole/linear ion-trap tandem mass spectrometry(UPLC-QTRAP-MS/MS).The UPLC conditions were as below: gradient elution with acetonitrile-0.1% formic acid, flow rate of 0.2 mL·min~(-1), column temperature of 30 ℃, sample chamber temperature of 10 ℃, and injection volume of 10 μL.The ESI~+and multiple reaction monitoring(MRM) were adopted for the MS.The above methods were used to determine the content of total flavonol glycosides and terpene lactones in 99 batches of Ginkgo Folium from 6 planting bases, and the results were statistically analyzed.The content of flavonoids and terpene lactones in Ginkgo Folium from different origins, from trees of different ages, harvested at different time, from trees of different genders, and processed with different methods was compared.The results showed that the content of total flavonol glucosides in 99 Ginkgo Folium samples ranged from 0.38% to 2.08%, and the total content of the four terpene lactones was in the range of 0.03%-0.87%.The method established in this study is simple and reliable, which can be used for the quantitative analysis of Ginkgo Folium.The research results lay a basis for the quality control of Ginkgo Folium.
Chromatography, High Pressure Liquid/methods*
;
Flavonoids/analysis*
;
Flavonols
;
Ginkgo biloba
;
Glycosides/analysis*
;
Lactones/analysis*
;
Methanol
;
Plant Leaves/chemistry*
;
Tandem Mass Spectrometry/methods*
;
Terpenes/analysis*
;
Trees

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