Optimization of fermentation conditions for the production of γ-aminobutyric acid by Lactobacillus hilgardii GZ2 from traditional Chinese fermented beverage system.

γ-Aminobutyric acid (GABA) is a crucial neurotransmitter with wide application prospects. In this study, we focused on a GABA-producing strain from a traditional Chinese fermented beverage system. Among the six isolates, Lactobacillus hilgardii GZ2 exhibited the greatest ability to produce GABA in the traditional Chinese fermented beverage system. To increase GABA production, we optimized carbon sources, nitrogen sources, temperature, pH, and monosodium glutamate and glucose concentrations and conducted fed-batch fermentation. The best carbon and nitrogen sources for GABA production and cell growth were glucose, yeast extract and tryptone. Gradual increases in GABA were observed as the glucose and monosodium glutamate concentrations increased from 10 g/L to 50 g/L. During fed-batch fermentation, lactic acid was used to maintain the pH at 5.56, and after feeding with 0.03 g/mL glucose and 0.4 g/mL sodium glutamate for 72 h, the GABA yield reached 239 g/L. This novel high-GABA-producing strain holds great potential for the industrial production of GABA, as well as the development of health-promoting functional foods and medical fields.

A universal strategy to enhance photothermal conversion efficiency by regulating the molecular aggregation states for safe photothermal therapy of bacterial infections.

Photothermal therapy (PTT) has emerged as a promising approach for treating bacterial infections. However, achieving a high photothermal conversion efficiency (PCE) of photothermal agents (PTAs) remains a challenge. Such a problem is usually compensated by the use of a high-intensity laser, which inevitably causes tissue damage. Here, we present a universal strategy to enhance PCE by regulating the molecular aggregation states of PTAs within thermoresponsive nanogels. We demonstrate the effectiveness of this approach using aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ) PTAs, showing significant enhancements in PCE without the need for intricate molecular modifications. Notably, the highest PCEs reach up to 80.9% and 64.4% for AIE-NG and ACQ-NG, respectively, which are nearly 2-fold of their self-aggregate counterparts. Moreover, we elucidate the mechanism underlying PCE enhancement, highlighting the role of strong intermolecular π-π interactions facilitated by nanogel-induced volume contraction. Furthermore, we validate the safety and efficacy of this strategy in in vitro and in vivo models of bacterial infections at safe laser power densities, demonstrating its potential for clinical translation. Our findings offer a straightforward, universal, and versatile method to improve PTT outcomes while minimizing cytotoxicity, paving the way for enhanced treatment of bacterial infections with safe PTT protocols.

Bacterial Patterning: A Promising Biofabrication Technique.

Bacterial patterning has emerged as a pivotal biofabrication technique in the biomedical field. In the past 2 decades, a diverse array of bacterial patterning approaches have been developed to enable the precise manipulation of the spatial distribution of bacterial patterns for various applications. Despite the significance of these advancements, there is a deficiency of review articles providing an overview of bacterial patterning technologies. In this mini-review, we systematically summarize the progress of bacterial patterning over the past 2 decades. This review commences with an elucidation of the definition and fundamental principles of bacterial patterning. Subsequently, we introduce the established bacterial patterning strategies, accompanied by discussions about the advantages and limitations of each approach. Furthermore, we showcase the biomedical applications of these strategies, highlighting their efficacy in spatial control of biofilms, biosensing, and biointervention. Finally, this mini-review is concluded with a summary and an outlook on future challenges and opportunities. It is anticipated that this mini-review can serve as a concise guide for those who are interested in this exciting and rapidly evolving research area.

Application of the Double Series Filter Technique for the Treatment of Acute Inferior Vena Cava Filter-Mediated Thrombosis.

BACKGROUND: In this study, we examined the safety and effectiveness of removing inferior vena cava (IVC) filters with residual acute thrombosis after endovascular therapy. METHODS: A retrospective chart review of 712 patients who underwent retrievable IVC filter implantation between July 2018 and December 2022 was conducted. Residual thrombosis with the IVC filter occurred in 18 patients, and the volume of residual acute thrombosis in the IVC filter exceeded 1 mL in all cases. Angiography was performed to evaluate the size of the residual thrombosis and its position with respect to the filter. The double series filter technique (first filter, infrarenal IVC filter; second filter, suprarenal IVC filter) was used to remove the filter and thrombosis. We summarize the diagnosis, treatment, and surgical experience of these patients. RESULTS: In this study, 16 of 18 patients (88.9%) demonstrated residual thrombosis in the IVC filter. One patient (5.6%) demonstrated thrombosis located both inside and floating above the filter, and one patient (5.6%) demonstrated thrombosis located both inside and underneath the filter. The technical success rate of double series IVC filter retrieval was 100%. Seventeen patients (94.4%) underwent single-stage suprarenal IVC filter retrieval, and one patient (5.6%, 1/18) underwent two-stage retrieval. In terms of residual thrombosis removal, 14 patients (77.7%) achieved complete removal and 4 patients (22.3%) achieved partial removal. Residual thrombosis could not be removed through the sheath in one patient, so femoral vein thrombectomy was performed. No other procedure-related complications were observed. The median follow-up time was 22.5 ± 6.8 months. No recurrence of thrombus symptoms was reported, and B ultrasound and computed tomography demonstrated smooth blood flow in the IVC, renal veins, and pulmonary artery. CONCLUSIONS: For patients with residual acute thrombosis on the IVC filter and in whom there was absence of a more appropriate treatment after percutaneous mechanical thrombectomy or catheter-directed thrombolysis therapy, the double series IVC filter technique was a safe approach to improve the IVC filter retrieval rate in the early stage, as well as for simultaneous residual thrombus removal.

Activated alkyne-enabled turn-on click bioconjugation with cascade signal amplification for ultrafast and high-throughput antibiotic screening.

Antimicrobial susceptibility testing plays a pivotal role in the discovery of new antibiotics. However, the development of simple, sensitive, and rapid assessment approaches remains challenging. Herein, we report an activated alkyne-based cascade signal amplification strategy for ultrafast and high-throughput antibiotic screening. First of all, a novel water-soluble aggregation-induced emission (AIE) luminogen is synthesized, which contains an activated alkyne group to enable fluorescence turn-on and metal-free click bioconjugation under physiological conditions. Taking advantage of the in-house established method for bacterial lysis, a number of clickable biological substances (i.e., bacterial solutes and debris) are released from the bacterial bodies, which remarkably increases the quantity of analytes. By means of the activated alkyne-mediated turn-on click bioconjugation, the system fluorescence signal is significantly amplified due to the increased labeling sites as well as the AIE effect. Such a cascade signal amplification strategy efficiently improves the detection sensitivity and thus enables ultrafast antimicrobial susceptibility assessment. By integration with a microplate reader, this approach is further applied to high-throughput antibiotic screening.

A Ratiometric Organic Fluorescent Nanogel Thermometer for Highly Sensitive Temperature Sensing.

Sensing temperature in biological systems is of great importance, as it is constructive to understanding various physiological and pathological processes. However, the realization of highly sensitive temperature sensing with organic fluorescent nanothermometers remains challenging. In this study, we report a ratiometric fluorescent nanogel thermometer and study its application in the determination of bactericidal temperature. The nanogel is composed of a polarity-sensitive aggregation-induced emission luminogen with dual emissions, a thermoresponsive polymer with a phase transition function, and an ionic surface with net positive charges. During temperature-induced phase transition, the nanogel exhibits a reversible and sensitive spectral change between a red-emissive state and a blue-emissive state by responding to the hydrophilic-to-hydrophobic change in the local environment. The correlation between the emission intensity ratio of the two states and the external temperature is delicately established, and the maximum relative thermal sensitivities of the optimal nanogel are determined to be 128.42 and 68.39% °C-1 in water and a simulated physiological environment, respectively. The nanogel is further applied to indicate the bactericidal temperature in both visual and ratiometric ways, holding great promise in the rapid prediction of photothermal antibacterial effects and other temperature-related biological events.

Bridging D-A type photosensitizers with the azo group to boost intersystem crossing for efficient photodynamic therapy.

Photodynamic therapy (PDT) has attracted much attention in disease treatments. However, the exploration of a novel method for the construction of outstanding photosensitizers (PSs) with stimuli-responsiveness remains challenging. In this study, we, for the first time, report a novel and effective strategy to boost reactive oxygen species (ROS) generation by bridging donor-acceptor (D-A) type PSs with the azo group. In contrast to the counterpart without azo-bridging, the azo-bridged PSs exhibit remarkably enhanced ROS generation via both type-I and type-II photochemical reactions. Theoretical calculations suggest that azo-bridging leads to a prominent reduction in ΔE ST, thereby enabling enhanced ROS generation via efficient intersystem crossing (ISC). The resulting azo-bridged PS (denoted as Azo-TPA-Th(+)) exhibits a particularly strong bactericidal effect against clinically relevant drug-resistant bacteria, with the killing efficiency up to 99.999999% upon white light irradiation. Since azo-bridging generates an azobenzene structure, Azo-TPA-Th(+) can undergo trans-to-cis isomerization upon UV irradiation to form emissive aggregates by shutting down the ISC channel. By virtue of the fluorescence turn-on property of unbound Azo-TPA-Th(+), we propose a straightforward method to directly discern the effective photodynamic bactericidal dose without performing the tedious plate-counting assay. This study opens a brand-new avenue for the design of advanced PSs with both strong ROS generation and stimuli-responsiveness, holding great potential in high-quality PDT with rapid prediction of the therapeutic outcome.

Suppression of the transforming growth factor-ß signaling pathway produces a synergistic effect of combination therapy with programmed death receptor 1 blockade and radiofrequency ablation against hepatic carcinoma in mice.

Primary liver cancer (PLC) significantly affects the health of patients globally owing to its high morbidity and low survival rate. Radiofrequency ablation (RFA) has recently been introduced for the clinical treatment of PLC. However, significant immunosuppressive effects are induced by RFA, which limits its application. This study aimed to explore the potential of combination therapy with RFA by investigating the effects of siRNAs against programmed death receptor 1 (PD-1) and transforming growth factor-ß (TGF-ß) on the antitumor effect induced by RFA. We observed that compared with si-NC, cell viability was reduced, apoptosis rate was elevated, release of inflammatory factors and percentage of CD3+CD8+ cells were increased, and the PI3K/AKT/mTOR pathway was repressed in the co-culture of RFA-treated H22 cells and CD8+ T cells by transfection with si-PD-1 and si-TGF-ß; these effects were further enhanced by co-transfection with si-PD-1 and si-TGF-ß. Additionally, in H22 cell xenograft-bearing mice treated with RFA, compared with the si-NC group, repressed tumor growth, prolonged survival, increased production of inflammatory factors and expression of CD3 and CD8 in tumor tissues, and downregulation of the PI3K/AKT/mTOR pathway were observed in the si-PD-1 and si-TGF-ß groups; these effects were further enhanced in the si-PD-1 + si-TGF-ß group. Taken together, our data revealed that suppression of the TGF-ß signaling pathway produced a synergistic antitumor effect of combination therapy with PD-1 blockade and RFA against PLC. [Figure: see text].

Polarity-Sensitive Fluorescent Probe for Reflecting the Packing Degree of Bacterial Membrane Lipids.

The maintenance of an intact membrane structure is of great importance for bacteria to execute various biological functions. However, chemical probes for monitoring the dynamic changes of bacterial membranes are barely reported. Herein, we, for the first time, report a novel polarity-sensitive probe for reflecting the packing degree of bacterial membrane lipids. Specifically, we synthesize a membrane-targeting fluorescent probe (TICT-lipid) that possesses both twist intramolecular charge transfer and aggregation-induced emission properties. TICT-lipid exhibits sensitive responses to the minute difference in the packing degree of membrane lipids, facilitating rapid differentiation of Gram-negative and Gram-positive bacteria. Interestingly, in the presence of membrane-disrupting antibiotics, the localization of TICT-lipid shifts from the outer membrane to the cell membrane by outputting blue-shifted and enhanced emission, making the mechanism of action of antibiotics clearly visible. TICT-lipid is a polarity-sensitive fluorescent probe, holding great promise in the study of membrane-related bacterial processes and antibiotic screening.

A Sensitive and Reliable Organic Fluorescent Nanothermometer for Noninvasive Temperature Sensing.

Sensing temperature at the subcellular level is of great importance for the understanding of miscellaneous biological processes. However, the development of sensitive and reliable organic fluorescent nanothermometers remains challenging. In this study, we report the fabrication of a novel organic fluorescent nanothermometer and study its application in temperature sensing. First of all, we synthesize a dual-responsive organic luminogen that can respond to the molecular state of aggregation and environmental polarity. Next, natural saturated fatty acids with sharp melting points as well as reversible and rapid phase transition are employed as the encapsulation matrix to correlate external heat information with the fluorescence properties of the luminogen. To apply the composite materials for biological application, we formulate them into colloidally dispersed nanoparticles by a technique that combines in situ surface polymerization and nanoprecipitation. As anticipated, the resultant zwitterionic nanothermometer exhibits sensitive, reversible, reliable, and multiparametric responses to temperature variation within a narrow range around the physiological temperature (i.e., 37 °C). Taking spectral position, fluorescence intensity, and fluorescence lifetime as the correlation parameters, the maximum relative thermal sensitivities are determined to be 2.15% °C-1, 17.06% °C-1, and 17.72% °C-1, respectively, which are much higher than most fluorescent nanothermometers. Furthermore, we achieve the multimodal temperature sensing of bacterial biofilms using these three complementary fluorescence parameters. Besides, we also fabricate a cationic form of the nanothermometer to facilitate efficient cellular uptake, holding great promise for studying thermal behaviors in biological systems.

Bringing naturally-occurring saturated fatty acids into biomedical research.

Naturally-occurring saturated fatty acids (NSFAs) have emerged as a class of promising biomaterials due to their low cost, chemical stability, well-defined melting points, large heat of fusion, reversible solid-liquid phase transition, biocompatibility, biodegradability, and inherent antibacterial activity. By virtue of these unique advantages, a plethora of attempts have been made by taking NSFAs as gating materials for controlled release or simply serving as bioactive substances for the manipulation of bacterial/cellular behaviors, which greatly boosts their widespread applications in biomedical research. In this review, we systematically summarize the advances of NSFA-based materials in the biomedical field over the past decade. We begin with an introduction to NSFAs and their physiochemical/biological properties, with an emphasis on the working mechanism for controlled release. We then discuss current approaches for the fabrication of colloidally dispersed NSFA-based materials. Further, we showcase the specific applications of NSFA-based materials in biomedical research, including controlled drug release, targeted drug delivery, cancer therapy, antibacterial treatment, and tissue engineering. Lastly, this review is concluded with a summary and perspectives on future directions.

Smart-planes fetal heart (S-planes FH) software to quantitative evaluate the fetal great arteries.

OBJECTIVES: To explore the feasibility of applying smart-planes fetal heart (S-Planes FH) to 3D volumes to generate and display the outflow tract views (OFTVs) and evaluate its agreement and reliability in determining fetal vessel dimensions. METHODS: A total of 147 normal fetuses in the second or third trimester were enrolled. Once conventional 2D sonographic examination was finished, one or more 3D static volumes were then acquired in the 4-chamber view (4CV). The OFTVs automatically generated and displayed via a simple offline operation using S-Planes FH software. Per fetus, a single qualified S-Planes FH image was selected by an expert. The inner diameters of the aorta (AO) and pulmonary artery (PA) were measured in 2D and S-Planes FH images, respectively. The agreement and reliability of the two methods were verified by the Bland-Altman method and the intraclass correlation coefficient (ICC), respectively. RESULTS: A total of 515 3D static volumes were successfully acquired in 147 fetuses. The OFTVs were generated and displayed using S-Planes FH in 138 (93.9%) cases. S-Planes FH had good agreement in measuring the diameters of great arteries (95% CI of limits, -0.9419 to 1.1464 for AO diameter, -0.8871 to 1.7007 for PA diameter). The intraobserver and interobserver ICCs in this study were greater than 0.81, indicating almost perfect reliability of the two methods with regard to observers. CONCLUSIONS: S-Planes FH software is a feasible method for generating OFTVs as well as determining vessel dimensions in the second and third trimesters and had good agreement with 2D examination. Therefore, it possesses clinical value in screening for CHD and can be operated by different sonographers.

Drug-eluting beads transarterial chemoembolization sequentially combined with radiofrequency ablation in the treatment of untreated and recurrent hepatocellular carcinoma.

BACKGROUND: Drug-eluting beads transarterial chemoem-bolization (DEB-TACE) has the advantages of slow and steady release, high local concentration, and low incidence of adverse drug reactions compared to the traditional TACE. DEB-TACE combined with sequentially ultrasound-guided radiofrequency ablation (RFA) therapy has strong anti-cancer effects and little side effects, but there are fewer related long-term studies until now. AIM: To explore the outcome of DEB-TACE sequentially combined with RFA for patients with primary hepatocellular carcinoma (HCC). METHODS: Seventy-six patients with primary HCC who underwent DEB-TACE sequentially combined with RFA were recruited. Forty patients with untreated HCC were included in Group A, and 36 patients with recurrent HCC were included in Group B. In addition, 40 patients with untreated HCC who were treated with hepatectomy were included in Group C. The serological examination, preoperative magnetic resonance imaging examination, and post-treatment computed tomography enhanced examination were performed for all patients. The efficacy was graded as complete remission (CR), partial remission (PR), stable disease and progressive disease at the 3rd, 6th, and 9th. All patients were followed up for 3 years and their overall survival (OS), disease-free survival (DFS) were assessed. RESULTS: The efficacy of Group A and Group C was similar (P > 0.05), but the alanine aminotransferase, aspartate aminotransferase and total bilirubin of Group A were lower than those of Group C (all P < 0.05). The proportions of CR (32.5%), PR (37.5%) were slightly higher than Group A (CR: 27.5%, PR: 35%), but the difference was not statistically significant (χ 2 = 0.701, P = 0.873). No operational-related deaths occurred in Group A and Group C. The OS (97.5%, 84.7%, and 66.1%) and the DFS (75.0%, 51.7%, and 35.4%) of Group A at the 1st, 2nd, and 3rd year after treatment were similar with those of Group C (OS: 90.0%, 79.7%, and 63.8%; DFS: 80.0%, 59.7%, and 48.6%; P > 0.05). The OS rates in Group A and Group B (90%, 82.3%, and 66.4%) were similar (P > 0.05). The DFS rates in Group B (50%, 31.6%, and 17.2%) were lower than that of Group A (P = 0.013). CONCLUSION: The efficacy of DEA-TACE combined with RFA for untreated HCC is similar with hepatectomy. Patients with recurrent HCC could get a longer survival time through the combined treatment.

Clinical analysis of ultrasound-guided radiofrequency ablation for recurrent colorectal liver metastases after hepatectomy.

BACKGROUND: RFA is designed to produce localized tumor destruction by heating the tumor and surrounding liver tissue, especially suitable for patients who do not qualify for hepatic resection. Many studies have reported that RFA was inferior to hepatectomy in the treatment of recurrent colorectal liver metastases. However, strong evidence is lacking in the literature. This study aimed to investigate the effect and clinical outcome of percutaneous ultrasound-guided RFA and repeat hepatic resection for recurrent colorectal liver metastases after hepatectomy. METHODS: From January 2007 to January 2014, 194 patients with recurrent colorectal liver metastases after hepatectomy diagnosed in our hospital was performed, and then divided into two groups based on different regimens: repeat hepatic resection group and RFA group. The clinical data of the two groups were analyzed. After treatment, the liver function-related indexes, complication rate, survival rate, and tumor recurrence of the two groups were recorded. The difference in short-term and long-term effects between repeat hepatic resection and RFA was identified by propensity score analysis. RESULTS: The number of metastases and the proportion of left and right lobe involved by tumor and preoperative chemotherapy in the RFA group were higher than those in the repeat hepatic resection group. The clinical data showed no significant difference between the two groups after using propensity score analysis. Compared with the RFA group, the liver function of the repeat hepatic resection group was significantly improved. After adjustment for potential confounders, no significant difference in liver function-related indexes was found between RFA and repeat hepatic resection, and the incidence of complications in the RFA group was lower. In survival analysis, there was no significant difference in OS and DFS between the two groups. CONCLUSIONS: RFA is a safe and effective therapeutic option for patients with recurrent colorectal liver metastases after hepatectomy.

Effect of STAT3 decoy oligodeoxynucleotides mediated by ultrasound-targeted microbubbles combined with ultrasound on the growth of squamous cell carcinoma of the esophagus.

Effect of STAT3 decoy oligodeoxynucleotides (ODN) transduced by ultrasound microbubbles combined with ultrasound on the growth of esophageal squamous cell carcinoma and its mechanism were analyzed. EC9706 cells were cultured in vitro and divided into four groups: group E (ultrasound microbubble + ultrasound irradiation), group P (liposome + ultrasound irradiation), group C (ultrasound), and group CC (ultrasound microbubbles). Mutant ODNs were used in groups E and P and the control group was group EC and PC, respectively. Immunofluorescence assay and flow cytometry were used to detect the transfection efficiency of each group. MTT colorimetric assay was performed to analyze the inhibition rate in each group. The effect of STAT3 decoy ODN on the proliferation of esophageal squamous carcinoma cells was calculated. Revese transcription-quantitative PCR (RT-qPCR) and western blotting were performed to detect the expression of the STAT signaling pathway downstream of gene expression levels. The model of subcutaneous transplantation of nude mice was used to show the effect of different transfections and STAT3 decoy ODN on the weight and volume of the transplanted tumor in mice. The cell inhibition rate was higher in group E than in groups P (F=8.382, P<0.001) and CC (F=6.469, P<0.001). Compared with groups EC, PC and C, respectively, the mRNA expression of STAT3, bcl-xL and Cyclin D1 decreased in groups E, P and CC (F=5.328, P<0.001). The weight and volume of nude mice in groups E, P and CC exhibited an inhibitory effect on the weight and volume of nude mice. Ultrasound irradiation combined with ultrasound microbubbles is an effective transfection method. The transfection of STAT3 decoy ODN can significantly inhibit the activity of esophageal squamous cell carcinoma cells and enhance apoptosis of cells, which has potential clinical value.

Cardiopulmonary bypass techniques and clinical outcomes in Beijing Fuwai Hospital: a brief clinical review.

The purpose of this study is to briefly summarize cardiopulmonary bypass (CPB) techniques and clinical outcomes in Beijing Fuwai Hospital. This article introduces routine CPB techniques in Fuwai Hospital, including CPB instruments, circuit setup, priming, conventional CPB management, myocardial protection, deep hypothermic circulatory arrest, ultrafiltration, autologous cell saver blood transfusion, and extracorporeal membrane oxygenation (ECMO). Clinical outcomes and further improvements of CPB management are also discussed. In 2008, 7,607 cases of cardiac surgery were performed in Fuwai Hospital, including congenital heart disease (48.33%), coronary artery disease (23.30%), rheumatic heart disease (19.45%), blood vessel disease (5.90%), reoperative surgery (1.70%), and other diseases (1.33%). The use of off-pump coronary artery bypass grafting (CABG) in isolated CABG was >50%. Thirty-eight cases of heart transplantation were also included. Total operative mortality in 2008 was 1.2%. Average postoperative stay was 9.5 days. CPB time was <120 minutes in >70% of the patients, and aortic cross-clamping time was <60 minutes in >50% of the cases. The self-recovery rate in the blood cardioplegia group (69.50%) was lower than the crystalloid cardioplegia group (97.40%). Thirty-five patients underwent cardiac surgery, and one patient from the cardiac internal medicine wards required ECMO support. Twenty-seven patients (75%, mean support time: 123.6 ± 54.1 hours) were weaned off ECMO successfully and discharged without severe complications. In conclusion, clinical CPB protocol used in Beijing Fuwai Hospital is a safe, simple, and conventional CPB management system that is suitable for practical clinical application in China. Further optimization is still needed to improve perfusion quality.

[Determination of 5-hydroxymethyl-furfural in root of Achyranthes bidentata expressing different degree of floating sugar].

OBJECTIVE: To study the relation between the content of 5-hydroxymethyl-furfural (5-HMF) and the degree of floating sugar in root of Achyranthes bidentata. METHOD: An HPLC method was applied with a Waters Symmetry C18 3.9 mm x 150 mm (5 microm) column by using methanol-water (12:88) as the mobile phase at a flow rate of 1.0 mL x min(-1) and a UV detection of 280 nm. RESULT: Along with the degree's deepening of floating sugar, the content of 5-HMF varied with the different shades of the sample. The content was 10 times higher in the black sample (highest degree of flowing suger) than that in the yellowish sample (normal). The concentrations of 5-HMT in five yellowish samples of roots of A. bidentata were 0.162 mg x g(-1) to 0.332 mg x g(-1). CONCLUSION: The content increasing of 5-HMF in the root of A. bidentata was related to the degree of flowing sugar.

[HPLC determination of chemical constituents produced in Radix Polygoni Multiflori after processing].

OBJECTIVE: To analysis the changes of two chemical constituents, namely 2, 3-dihydro-3, 5- dihydroxy-6-methyl-4H-pyran-4-one (DDMP) and 5-hydryoxymethyl-furfural (5-HMF) produced in Radix Polygoni Multiflori after processing, with processing time, and to determine the contents of 5-HMF in samples of Radix Polygoni Multiflori and Radix Polygoni Multiflori preparata. METHOD: An HPLC method was applied with a Zobax SB-C18 (3.9 mm x 150 mm, 5 microm) column by a elution using methanol-water (10: 90) as the mobile phase. The detection was set at UV 280 nm. RESULT: The contents of DDMP were increasing with the processing time until 24 hour, followed by a decrease until 60 hour process. The contents of 5-HMF were increasing gradually throughout the 60 hour steaming process. The contents of 5-HMF in 11 samples of Radix Polygoni Multiflori preparata were from 0.013% to 0.101%, and only one in 4 samples of Radix Polygoni Multiflori containing trace amount of 5-HMF. CONCLUSION: The chemical components in Radix Polygoni Multiflori were changed during the processing procedures. Therefore, the processing of Radix Polygoni Multiflori should be controlled and standardized.