Objective To develop a reversed-phase high-performance liquid chromatography(RP-HPLC) method for the determination of residual phenylmethanesulfonyl fluoride(PMSF) content in recombinant virus-like particle(VLP) vaccine stock solution,and to verify the method for the determination of PMSF residues in recombinant VLP vaccine stock solution.Methods A RP-HPLC method for the determination of PMSF residues was developed by screening detection wavelength,flow rate,injection amount and chromatographic column.The specificity,linearity and range,limit of quantitation(LOQ),limit of detection(LOD),accuracy,precision and durability of the method were verified.The developed method was used to detect PMSF residues in three batches of recombinant hepatitis E vaccine stock solution.Results The RP-HPLC method was developed,with ChromCore 300 C18(4.6 mm × 250 mm,5 μm) as the chromatographic column at the column temperature of 25 ℃,the detection wavelength of 210 nm,the injection amount of 100 μL,0.1% trifluoroacetic acid(TFA)/water and0.1% TFA/acetonitrile as mobile phase at a flow rate of 1 mL/min,and the detection time of 18 min.The absorption peaks of PMSF control and vaccine stock solution containing PMSF appeared around 5.0 min,while the vaccine stock solution and stock solution buffer showed no absorption peak.There was a good linear relationship between the concentration of PMSF control and peak area in the range of 0-5.0 μg/mL,with R~2 of 0.999.The LOQ and LOD of this method was 0.250 μg/mL and 0.125 μg/mL,respectively.The recovery rates of PMSF control with high,medium and low concentrations were all between 90% and 110%.The relative standard deviations(RSDs) of retention time,peak height and peak area for the determination of instrument repeatability,sample repeatability and intermediate precision were all less than 5%.The RSDs of retention time,peak height and peak area were all less than 5% under the TFA concentration of 0.09%,0.1% and 0.11% at column temperature of 20,25 and 30 ℃.PMSF was not detected in the three batches of recombinant hepatitis E vaccine stock solution.Conclusion The developed RP-HPLC method has good specificity,linearity and durability,high accuracy and precision,and can be used to detect residual PMSF content in recombinant VLP vaccine stock solution.
Phenylmethanesulfonyl fluoride(PMSF) ; Reversed-phase high-performance liquid chromatography(RP-HPLC) ; Virus-like particle(VLP) vaccine

OBJECTIVE

This study aimed to determine and quantify the presence of the active components in Thai propolis extracts using high performance liquid chromatography (HPLC). Moreover, the anti-caries potential of Thai propolis extract and its active ingredients were tested.

Fifty milligrams of Thai propolis were extracted using either 100%, 90%, 80%, or 70% ethanol and subsequently analyzed using HPLC with a mobile phase gradient system of 10-100% acetonitrile in 0.05% aqueous ortho-phosphoric acid, flow rate of 0.8 mL/min, and detection wavelength of 280 nm. Varying concentrations of Thai propolis extracts as well as four active ingredients were subjected to agar well diffusion test against the growth of Streptococcus mutans (S. mutans) or Lactobacillus caseii (L. caseii).

The concentrations of the four active ingredients: vicenin-2, vitexin, apigenin, and cinnamic acid, were significantly affected by ethanolic concentrations. The chromatographic peaks of all active ingredients from 70% and 80% ethanolic extracts appeared more defined, as compared to those which used higher concentrations of ethanol for extraction. Except for the absolute ethanolic extract, all of the examined propolis extracts, as well as its active ingredients inhibited both S. mutans and L. caseii.

Thai propolis extracts contain vicenin-2, vitexin, apigenin, and cinnamic acid as part of its active ingredients. These were found to be significantly affected by the increase in ethanol during its extraction. The presence of these active ingredients might have contributed to the anti-caries potential of Thai propolis extracts.

Objectives: The aim of this study is to establish a Reversed Phase – High Performance Liquid Chromatographic (RP-HPLC) method for the quantification of Rhein from Cassia fistula L. leaves. Methods: A Shimadzu system equipped with a C18 Column (150 x 4.6 mm, 5 μm) with an isocratic elution of Acetonitrile (solvent A) and 0.1% trifluoroacetic acid aqueous solution (solvent B) (Merck, 1.08178.0050) with a 55:45 ratio, respectively and a flow rate of 1.0 mL/min and sample injection of 10 μL detection was done at 230 nm. Standard solution of Rhein (Chengdu Biopurify) was prepared for method development. This study was validated using the guidelines set under “ICH Topic Q2 R2 or the Validation of Analytical Procedures”. Procedures for linearity, precision, accuracy, limit of detection, and limit of quantitation were performed. Results: The retention time of Rhein standard was determined at 5.10 minutes. LOD and LOQ were determined to be 1.278 mcg/mL and 3.872 mcg/mL, respectively with good linearity (R2 ≥0.996) with a linear range of 2.5-20 ug/mL of the Rhein standard. The accuracy of the method was determined based on % recovery method and ranged from 94.75%-100.32% (intraday, n=3) with %RSD of 0.71. The intraday precision %RSD was 2.92 (n=6) while interday precision %RSD was 3.75 (n=3). The method was able to check the Rhein quantity among 10 samples of Cassia fistula L. leaves from different locations in the Philippines. Conclusion The method was found to be sensitive and accurate for the quantification of Rhein. The method was found to be useful for the quantification of the amount of Rhein and can be used as a Quality Control tool for the assessment of Cassia fistula.
Cassia ; Chromatography, High Pressure Liquid

Male ; Humans ; Liquid Chromatography-Mass Spectrometry ; Chromatography, Liquid ; Tandem Mass Spectrometry ; Varicocele/diagnosis* ; Biomarkers

OBJECTIVES

The aim of this study is to establish a Reversed Phase – High Performance Liquid Chromatographic (RP-HPLC) method for the quantification of Rhein from Cassia fistula L. leaves.

A Shimadzu system equipped with a C18 Column (150 x 4.6 mm, 5 μm) with an isocratic elution of Acetonitrile (solvent A) and 0.1% trifluoroacetic acid aqueous solution (solvent B) (Merck, 1.08178.0050) with a 55:45 ratio, respectively and a flow rate of 1.0 mL/min and sample injection of 10 μL detection was done at 230 nm. Standard solution of Rhein (Chengdu Biopurify) was prepared for method development. This study was validated using the guidelines set under “ICH Topic Q2 R2 or the Validation of Analytical Procedures”. Procedures for linearity, precision, accuracy, limit of detection, and limit of quantitation were performed.

The retention time of Rhein standard was determined at 5.10 minutes. LOD and LOQ were determined to be 1.278 mcg/mL and 3.872 mcg/mL, respectively with good linearity (R2 ≥0.996) with a linear range of 2.5-20 ug/mL of the Rhein standard. The accuracy of the method was determined based on % recovery method and ranged from 94.75%-100.32% (intraday, n=3) with %RSD of 0.71. The intraday precision %RSD was 2.92 (n=6) while interday precision %RSD was 3.75 (n=3). The method was able to check the Rhein quantity among 10 samples of Cassia fistula L. leaves from different locations in the Philippines.

The method was found to be sensitive and accurate for the quantification of Rhein. The method was found to be useful for the quantification of the amount of Rhein and can be used as a Quality Control tool for the assessment of Cassia fistula.

Objective: This study aimed to determine and quantify the presence of the active components in Thai propolis extracts using high performance liquid chromatography (HPLC). Moreover, the anti-caries potential of Thai propolis extract and its active ingredients were tested. Methods: Fifty milligrams of Thai propolis were extracted using either 100%, 90%, 80%, or 70% ethanol and subsequently analyzed using HPLC with a mobile phase gradient system of 10-100% acetonitrile in 0.05% aqueous ortho-phosphoric acid, flow rate of 0.8 mL/min, and detection wavelength of 280 nm. Varying concentrations of Thai propolis extracts as well as four active ingredients were subjected to agar well diffusion test against the growth of Streptococcus mutans (S. mutans) or Lactobacillus caseii (L. caseii). Results: The concentrations of the four active ingredients: vicenin-2, vitexin, apigenin, and cinnamic acid, were significantly affected by ethanolic concentrations. The chromatographic peaks of all active ingredients from 70% and 80% ethanolic extracts appeared more defined, as compared to those which used higher concentrations of ethanol for extraction. Except for the absolute ethanolic extract, all of the examined propolis extracts, as well as its active ingredients inhibited both S. mutans and L. caseii. Conclusions Thai propolis extracts contain vicenin-2, vitexin, apigenin, and cinnamic acid as part of its active ingredients. These were found to be significantly affected by the increase in ethanol during its extraction. The presence of these active ingredients might have contributed to the anti-caries potential of Thai propolis extracts.
flavonoids ; chromatography, high performance liquid

INTRODUCTION

One of the novel strategies in cancer treatment is the combination of conventional chemotherapeutic drugs and natural products. In a previous study, co-treatment of the anti-cancer drug cyclophosphamide (CP) with honey from giant honey bee (Apis dorsata) resulted to a dose-dependent increase in its cytotoxic effect in human lung carcinoma (A549) cells. However, the molecular mechanism of this combinatorial effect remains unknown.

In this study, the effect of A. dorsata honey on the expression of selected CYP450 genes at the mRNA level, as well as the proapoptotic gene CASP8 and antiapoptotic gene BCL2 was investigated in CP-treated A549 cells.

MTT Assay was performed to determine the cell viability of A549 cells after treatment with CP with or without A. dorsata honey, as well as the EC50 of CP with honey thereafter. RT-qPCR was then performed to study the effect of A. dorsata honey on the expression of selected CYP450 genes as well as CASP8 and BCL2 genes in CPtreated A549 cells. LC-MS was carried out to screen for putative compounds in A. dorsata honey which may possibly have anti-cancer activity.

Honey in the lowest concentration (0.6% v/v) most effectively enhanced the cytotoxic effect of CP. CYP2J2 and CYP1B1 indicated a 2.38-fold and 1.49-fold upregulation, respectively as compared to untreated cells. This cytotoxic effect is further enhanced by upregulation of CASP8 that is paralleled by a downregulation of BCL2. Phytosphingosine and sphinganine are honey constituents which may be linked to the increased cytotoxicity of CP observed in A549 cells.

This study provides further knowledge on the molecular basis by which A. dorsata honey potentiates the cytotoxic effect of cyclophosphamide in A549 cells.

Although polyurethane (PUR) plastics play important roles in daily life, its wastes bring serious environmental pollutions. Biological (enzymatic) degradation is considered as an environmentally friendly and low-cost method for PUR waste recycling, in which the efficient PUR-degrading strains or enzymes are crucial. In this work, a polyester PUR-degrading strain YX8-1 was isolated from the surface of PUR waste collected from a landfill. Based on colony morphology and micromorphology observation, phylogenetic analysis of 16S rDNA and gyrA gene, as well as genome sequence comparison, strain YX8-1 was identified as Bacillus altitudinis. The results of high performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) showed that strain YX8-1 was able to depolymerize self-synthesized polyester PUR oligomer (PBA-PU) to produce a monomeric compound 4, 4'-methylene diphenylamine. Furthermore, strain YX8-1 was able to degrade 32% of the commercialized polyester PUR sponges within 30 days. This study thus provides a strain capable of biodegradation of PUR waste, which may facilitate the mining of related degrading enzymes.
Polyurethanes/chemistry* ; Polyesters/chemistry* ; Chromatography, Liquid ; Phylogeny ; Tandem Mass Spectrometry ; Bacteria/metabolism* ; Biodegradation, Environmental

This study aimed to investigate the impact of ginger juice on chemical profile of Magnoliae Officinalis Cortex(MOC) when they were processed together. Ultra-high-performance liquid chromatography coupled to quadrupole-orbitrap high-resolution mass spectrometry(UHPLC-Q-Orbitrap HRMS) was used for qualitative analysis of the chemical component of MOC samples before and after being processed with ginger juice. UPLC was performed to observe the content variation of eight main components in processed MOC. A total of 174 compounds were identified or tentatively deduced from processed and unprocessed MOC samples according to MS data obtained in positive and negative ion mode. After MOC was processed with ginger juice, the peak areas of most phenolics increased, while the peak areas of most phenylethanoid glycosides decreased; as for neolignans, oxyneolignans, other lignans and alkaloids, changes in the peak area were variable, and the peak areas of terpenoid-lignans varied little. Additionally, gingerols and diarylheptanoids were only detected in the processed MOC sample. The contents of syringin, magnoloside A, and magnoloside B decreased significantly in the processed MOC sample while no significant difference was observed in the contents of magnoflorine, magnocurarine, honokiol, obovatol, and magnolol. This study comprehensively explored the content variation of chemical components in processed and unprocessed MOC samples derived from different regions and with different tree ages using UPLC and UHPLC-Q-Orbitrap HRMS, and summarized the variation characteristics of various compounds. The results provide a data foundation for further research on pharmacodynamic substances of MOC processed with ginger juice.
Ginger ; Trees ; Chromatography, High Pressure Liquid/methods* ; Alkaloids ; Lignans/analysis*

In order to comprehensively evaluate the quality of Viticis Fructus, this study established HPLC fingerprints and evaluated the quality of 24 batches of Viticis Fructus samples from different species by similarity evaluation and multivariate statistical analysis(PCA, HCA, PLS-DA). On this basis, an HPLC method was established to compare the content differences of the main components, including casticin, agnuside, homoorientin, and p-hydroxybenzoic acid. The analysis was performed on the chromatographic column(Waters Symmetry C_(18)) with a gradient mobile phase of acetonitrile(A)-0.05% phosphoric acid solution(B) at the flow rate of 1 mL·min~(-1) and detection wavelength of 258 nm. The column temperature was 30 ℃ and the injection volume was 10 μL. The HPLC fingerprint of 24 batches of Viticis Fructus samples was established with 21 common peaks, and nine peaks were identified. Similarity analysis was carried out based on chromatographic data of 24 batches of chromatographic data of Viticis Fructus, and the results showed that except for DYMJ-16, the similarity of Vitex trifolia var. simplicifolia was ≥0.900, while that of V. trifolia was ≤0.864. In addition, the similarity analysis of two different species showed that the similarity of 16 batches of V. trifolia var. simplicifolia was 0.894-0.997 and that of the eight batches of V. trifolia was between 0.990 and 0.997. The results showed that the similarity of fingerprints of these two species was different, but the similarity between the same species was good. The results of the three multivariate statistical analyses were consistent, which could distinguish the two different species. The VIP analysis results of PLS-DA showed that casticin and agnuside contributed the most to the distinction. The content determination results showed that there was no significant difference in the content of homoorientin and p-hydroxybenzoic acid in Viticis Fructus from different species, but the content of casticin and agnuside was significantly different in different species(P<0.01). The content of casticin was higher in V. trifolia var. simplicifolia, while agnuside was higher in V. trifolia. The findings of this study show that there are differences in fingerprint similarity and component content of Viticis Fructus from different species, which can provide references for the in-depth study of the quality and clinical application of Viticis Fructus.
Drugs, Chinese Herbal/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Fruit/chemistry* ; Vitex/chemistry*