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A novel hyphenated technique based on ultrasonic-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled with derivatization has been established for the determination of brassinolide (BL, a representative of brassinosteroids) by HPLC fluorescence detection. 9-Phenanthreneboronic acid is used as labeling reagent of BL. UA-DLLME parameters containing type and volume of extraction and disperser solvent, pH and ultrasonication time are optimized. Derivatization parameters are optimized included amount of 9-phenanthreneboronic acid, volume ratio of pyridine, derivatization time and temperature. Under optimal conditions, quantitative linear range of BL is 50-1,000 ng L<sup>−1</sup> and excellent linear response is observed with correlation coefficient of 0.9996. Limit of detection and limit of quantification are calculated as 8.0 and 25.0 ng L<sup>−1</sup>, respectively. RSDs of retention time and peak area are in the range of 0.68-0.97 % and 4.61-6.54 % for intra-day precision, 1.32-1.94 % and 7.28-9.75 % for inter-day precision, respectively. Accuracy is satisfactory in the range of 82.3-125.1 %. RSDs’ values of repeatability are in the range of 0.82-1.79 and 3.95-8.53 % for retention time and peak area, respectively. Enrichment factor for BL is 189. The results of recovery and matrix effect are in the range of 82.0-108.6 and 90.0-115.3 %, respectively. The proposed method has been applied for the determination of BL in <i>Arabidopsis thaliana</i>, <i>Daucus carota</i> and <i>Brassica campestris</i> L. leaves with much higher sensitivity than many other methods.

OBJECTIVE: It has been speculated that cancer survivors in Asia may have lower quality of life (QOL) compared with their Western counterparts. However, no studies have made international comparisons in QOL using a comprehensive measure. This study aimed to compare Chinese breast cancer survivors' QOL with US counterparts and examine if demographic and medical factors were associated with QOL across groups. METHOD: The sample consisted of 159 breast cancer patients (97 Chinese and 62 American) who completed the Functional Assessment for Cancer Therapy Breast Cancer (FACT-B) scale before the start of radiotherapy in Shanghai, China and Houston, USA. RESULTS: Higher income was associated with higher QOL total scores in both Chinese and American cancer patients, but QOL was not significantly associated with other factors including age, education, disease stage, mastectomy, and chemotherapy. Consistent with hypotheses, compared to their US counterparts, Chinese breast cancer survivors reported lower QOL and all four subdimensions including functional well-being (FWB), physical well-being (PWB), emotional well-being (EWB), and social well-being (SWB); they also reported more breast cancer-specific concerns (BCS). Differences were also clinically significant for Functional Assessment for Cancer Therapy General (FACT-G) scale total scores and the FWB subscale. After controlling for demographic and medical covariates, these differences remained except for the SWB and BCS. Furthermore, Chinese breast cancer survivors receiving chemotherapy reported significantly lower FACT-G scores than those who did not, but this difference did not emerge among US breast cancer survivors. DISCUSSION: Chinese breast cancer survivors reported poorer QOL on multiple domains compared to US women. Findings indicate that better strategies are needed to help improve the QOL of Chinese breast cancer survivors, especially those who underwent chemotherapy.

• A new low toxic dual-UADLLME coupled with microwave-assisted derivatization was proposed. • 4′-Carboxy-substituted rosamine was firstly used as derivatization reagent. • Simultaneous determination of PPD and PPT in rat plasma was achieved by UHPLC-MS/MS. • This method was successfully applied to pharmacokinetics study.<br>This paper, for the first time, reported a speedy hyphenated technique of low toxic dual ultrasonic-assisted dispersive liquid-liquid microextraction (dual-UADLLME) coupled with microwave-assisted derivatization (MAD) for the simultaneous determination of 20(<b>S</b>)-protopanaxadiol (PPD) and 20(<b>S</b>)-protopanaxatriol (PPT). The developed method was based on ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection using multiple-reaction monitoring (MRM) mode. A mass spectrometry sensitizing reagent, 4′-carboxy-substituted rosamine (CSR) with high reaction activity and ionization efficiency was synthesized and firstly used as derivatization reagent. Parameters of dual-UADLLME, MAD and UHPLC-MS/MS conditions were all optimized in detail. Low toxic brominated solvents were used as extractant instead of traditional chlorinated solvents. Satisfactory linearity, recovery, repeatability, accuracy and precision, absence of matrix effect and extremely low limits of detection (LODs, 0.010 and 0.015 ng/mL for PPD and PPT, respectively) were achieved. The main advantages were rapid, sensitive and environmentally friendly, and exhibited high selectivity, accuracy and good matrix effect results. The proposed method was successfully applied to pharmacokinetics of PPD and PPT in rat plasma.

This quasi-experimental study attempted to show that nursing intervention using the DanJeon Breathing Exercise Program (DJBEP) improved the quality of life of recipients after kidney transplantation. DJBEP progressed in three steps. We prospectively included 29 outpatient volunteers: experimental group: n ϭ 15; control group: n ϭ 14. DJBEP derived from the Roy’s adaptation model decreased both the stress and the uncertainty of kidney transplantation recipients. It has also been shown to restore serum cholesterol and serum creatinine levels and enhance strength and flexibility. Simultaneously, self-esteem was enhanced, and eventually adaptation was promoted both physiologically and psychologically. The quality of life of kidney transplantation recipients was enhanced. DJBEP played an effective role as a nursing intervention to promote the quality of life of kidney transplant patients by increasing their physiological and psychological status.

The medicines targeted at α-glucosidase played an important role in anti-diabetes and anti-HIV therapy. Unfortunately, the method based on fluorescent assay strategy for α-glucosidase inhibitor screening remains poorly investigated. In this study, a novel "Turn On" fluorescence sensor platform has been developed for trace α-glucosidase inhibitor screening from natural medicines. Firstly, carbon dots were prepared by one-pot synthesis and used as the signal output. Combining with the carbon dots, cobalt oxyhydroxide (CoOOH) nanoflakes were employed to build the fluorescence resonance energy transfer (FRET) based sensor platform. Secondly, L-ascorbic acid-2-O-α-D-glucopyranosyl (AAG) was innovatively introduced as α-glucosidase substrate. With hydrolysis of AAG by α-glucosidase, ascorbic acids (AA) were released that can rapidly reduce CoOOH nanoflakes to Co(2+), and then FRET was stopped accompanying with the fluorescence recovery of CDs. The sensor platform was ultrasensitive to AA with a detection limit of 5 nM, ensuring the sensitive monitoring of enzyme activity. Acarbose was used as the inhibitor model and its inhibition rate is proportional to the logarithm of concentration in range of 10(-9)-10(-3)M with the correlation coefficient of R(2)=0.996, and an ultralow limit of detection of ~1×10(-9)M was obtained. The inhibiting ability of seven compounds isolated from natural medicines was also evaluated. The constructed sensor platform was proven to be sensitive and selective as well as cost-effective, facile and reliable, making it promising as a candidate for trace α-glucosidase inhibitor screening.

AIM: Fructus phyllanthi tannin fraction (PTF) from the traditional Tibetan medicine Fructus phyllanthi has been found to inhibit lung and liver carcinoma in mice. In this study we investigated the anticancer mechanisms of PTF in human lung squamous carcinoma cells in vitro.METHODS: Human lung squamous carcinoma cell line (NCI-H1703), human large-cell lung cancer cell line (NCI-H460), human lung adenocarcinoma cell line (A549) and human fibrosarcoma cell line (HT1080) were tested. Cell viability was detected with MTT assay. Cell migration and invasion were assessed using a wound healing assay and a transwell chemotaxis chambers assay, respectively. Cell apoptosis was analyzed with flow cytometric analysis. The levels of apoptosis-related and metastasis-related proteins were detected by Western blot and immunofluorescence. RESULTS: PTF dose-dependently inhibited the viability of the 3 human lung cancer cells. The IC50 values of PTF in inhibition of NCI-H1703, NCI-H460, and A549 cells were 33, 203, and 94 mg/L, respectively. PTF (15, 30, and 60 mg/L) dose-dependently induced apoptosis of NCI-H1703 cells. Treatment of NCI-H1703 and HT1080 cells with PTF significantly inhibited cell migration, and reduced the number of invasive cells through Matrigel. Furthermore, PTF dose-dependently down-regulated the expression of phosphor-ERK1/2, MMP-2 and MMP-9, up-regulated the expression of phosphor-JNK, but had no significant effect on the expression of ERK1/2 or JNK. CONCLUSION: PTF induces cell apoptosis and inhibits the migration and invasion of NCI-H1703 cells by decreasing MPPs expression through regulation of the MAPK pathway.

AIM: Fructus phyllanthi tannin fraction (PTF) from the traditional Tibetan medicine Fructus phyllanthi has been found to inhibit lung and liver carcinoma in mice. In this study we investigated the anticancer mechanisms of PTF in human lung squamous carcinoma cells in vitro. METHODS: Human lung squamous carcinoma cell line (NCI-H1703), human large-cell lung cancer cell line (NCI-H460), human lung adenocarcinoma cell line (A549) and human fibrosarcoma cell line (HT1080) were tested. Cell viability was detected with MTT assay. Cell migration and invasion were assessed using a wound healing assay and a transwell chemotaxis chambers assay, respectively. Cell apoptosis was analyzed with flow cytometric analysis. The levels of apoptosis-related and metastasis-related proteins were detected by Western blot and immunofluorescence. RESULTS: PTF dose-dependently inhibited the viability of the 3 human lung cancer cells. The IC50 values of PTF in inhibition of NCI-H1703, NCI-H460, and A549 cells were 33, 203, and 94 mg/L, respectively. PTF (15, 30, and 60 mg/L) dose-dependently induced apoptosis of NCI-H1703 cells. Treatment of NCI-H1703 and HT1080 cells with PTF significantly inhibited cell migration, and reduced the number of invasive cells through Matrigel. Furthermore, PTF dose-dependently down-regulated the expression of phosphor-ERK1/2, MMP-2 and MMP-9, up-regulated the expression of phosphor-JNK, but had no significant effect on the expression of ERK1/2 or JNK. CONCLUSION: PTF induces cell apoptosis and inhibits the migration and invasion of NCI-H1703 cells by decreasing MPPs expression through regulation of the MAPK pathway.

A green, simple and sensitive method was developed for the analysis of volatile carboxylic acids (VFAs) and perfluorocarboxylic acids (PFCAs) in food packaging materials. The acidic compounds in food packaging materials were first extracted by gas purge microsyringe extraction (GP-MSE) with 1.0 mL 0.1 mol·L<sup>−1</sup> NaOH solution, then the analytes were dispersive liquid-liquid microextracted (DLLME) by 50 μL chloroform as extraction solvent and 200 μL acetonitrile as dispersive solvent. The 2-(5-Benzoacridine) ethyl-p-toluenesulfonate (BAETS) with excellent fluorescence property was applied to enhance the high performance liquid chromatography (HPLC) sensitivity. The obtained recoveries for the VFAs ranged from 92.0 to 101 %. The method LODs calculated at a signal-to-noise ratio (S/N) of 3 were in the range of 0.80-3.40 μg·kg<sup>−1</sup>, while the LOQs calculated at S/N of 10 were in the range of 2.5-10.2 μg·kg<sup>−1</sup>. All compounds were in good linearity with concentration coefficients of higher than 0.997. Perfluorooctanoic acid (PFOA) was found in all of the 15 kinds of samples analyzed with concentrations ranging from 4.86-7.56 μg·kg<sup>−1</sup>. Acetic acid, butyric acid, and caprylic acid were found in half of the samples analyzed. The other analytes were also found in more than 30 % samples with concentrations varied between 3.96 and 293 μg·kg<sup>−1</sup>.

In this study, a green, simple, and sensitive method was developed for the analysis of aliphatic aldehyde s from fried meat by using a modified gas purge-microsyringe extraction (GP-MSE) system in combination with high-performance liquid chromatography (HPLC) with fluorescence detection. The modified GP-MSE system possessed two gas channels and showed better recoveries for compounds with diverse density in comparison with one gas channel GP-MSE system. Target compounds in fried meat were effectively extracted without the traditional solvent extraction and lipid removing process, while the HPLC sensitivity of aldehyde s was enhanced by introducing 2-(12-benzo[b]acridin-5(12H)-yl)-acetohydrazide (BAAH) with excellent fluorescence property into the molecules. Parameters influencing the extraction efficiency and HPLC sensitivity were optimized. The limits of detection (LODs) ranged from 0.30 to 0.45 μg/kg, and the limits of quantification (LOQs) ranged from 1.0 to 1.5 μg/kg. The recoveries of the target compounds were in the range of 86.9 to 95.6%. The proposed method was successfully applied to the analysis of aldehyde s in fried meat samples. Formaldehyde, acetaldehyde, pentanal, hexanal, heptanal, octanal, nonaldehyde, and decanal were all found in fried meat samples with concentrations ranging from 0.05 to 17.8 mg/kg.

Fatty acids in Herpetospermum seed oil from supercritical CO2 extraction were analyzed by HPLC fluorescence detection (HPLC-FLD) with pre-column derivatization and GC-MS. After derivatizing 39 kinds of saturated and unsaturated fatty acids used 1-[ 2- ( p-toluenesulfonate ) ethyl]-2-phenylimidazole [ 4,5-f] 9,10-phenanthrene ( TSPP ) as pre-column derivatization reagent. All the fatty acid derivatives were separated with a good baseline resolution in conjunction with a gradient elution. The external standard method for the simultaneous quantitative determination of 39 fatty acids was developed and applied for the determination of the free fatty acid contents in Herpetospermum seed oil samples obtained from supercritical CO2 extraction coupled with orthogonal tests, ultrasound-assisted extraction and microwave-assisted reflux extraction. The mass percent of oleic acid, linoleic acid and linolenic acid and the ratio of unsaturated fatty acids and all fatty acids in 9 orthogonal test samples were contrasted. The results indicated that the mass percent of oleic acid, linoleic acid and linolenic acid in Herpetospermum seed oil are up to 34.65% ( 147. 14 mg/g), 22.85% (97.03 mg/g), 20. 86% ( 88. 56 rag/g), respectively, and ratio of unsaturated fatty acids and all fatty acids is 79%. Furthermore, by GC-MS method, the acid catalysis and alkaline catalysis of the methyl esterifying reaction were discussed for the analysis fatty acids in Herpetospermum seed oil, and the optimum GC-MS conditions were obtained. Simultaneously, the characteristics of HPLC and GC-MS methods were discussed about analyzing fatty acids.

&lt;p&gt;A simple and sensitive method for the determination of free fatty acids (FFAs) using acridone€́9€́ethyl€́p€́toluenesulfonate (AETS) as a fluorescence derivatization reagent by high performance liquid chromatography (HPLC) has been developed. Free fatty acid derivatives were separated on an Eclipse XDB€́C&lt;sub&gt;8&lt;/sub&gt; column with a good baseline resolution and detected with the fluorescence of which excitation and emission wavelengths of derivatives were set at &lt;sub&gt;ex&lt;/sub&gt;=404 and &lt;sub&gt;em&lt;/sub&gt;=440 nm, respectively. Identification of 19 fatty acid derivatives was carried out by online post€́column mass spectrometry with an atmospheric pressure chemical ionization (APCI) source under positive€́ion detection mode. Nineteen FFAs from the extract of &lt;i&gt;Lomatogonium rotatum&lt;/i&gt; are sensitively determined. The results indicate that the plant &lt;i&gt;Lomatogonium rotatum&lt;/i&gt; is enriched with an abundance of FFAs and FFAs of higher contents, which mainly focus on even carbon atoms, C&lt;sub&gt;14&lt;/sub&gt;, C&lt;sub&gt;16&lt;/sub&gt;, and C&lt;sub&gt;18&lt;/sub&gt;. The validation of the method including linearity, repeatability, and detection limits was examined. Most linear correlation coefficients for fatty acid derivatives are &gt;0.9989, and detection limits (at signal€́to€́noise of 3:1) are 12.3-43.7 fmol. The relative standard deviations (RSDs) of the peak areas and retention times for 19 FFAs standards are &lt;2.24% and 0.45%, respectively. The established method is rapid and reproducible for the separation determination of FFAs from the extract of &lt;i&gt;Lomatogonium rotatum&lt;/i&gt; with satisfactory results.&lt;/p&gt;

In this study, a simple analytical method for the determination of γ-aminobutyric acid, gabapentin, and baclofen by using high-performance liquid chromatography with fluorescence detection was developed. An amidogen-reactive fluorescence labeling reagent, 4-(carbazole-9-yl)-benzyl chloroformate was first used to sensitively label these analytes. The completed labeling of these analytes can be finished rapidly only within 5 min at the room temperature (25°C) to form 4-(carbazole-9-yl)-benzyl chloroformate labeled fluorescence derivatives. These labeled derivatives expressed strong fluorescence property with the maximum excitation and emission wavelengths of 280 and 380 nm, respectively. The labeled derivatives were analyzed using a reversed-phase Eclipse SB-C18 column within 10 min with satisfactory shapes. Excellent linearity (R² > 0.995) for all analytes was achieved with the limits of detection and the limits of quantitation in the range of 0.25−0.35 and 0.70−1.10 μg/L, respectively. The proposed method was used for the simultaneous determination of γ-aminobutyric acid and its analogs in human serum with satisfactory recoveries in the range of 94.5-97.5%.

This study established an HPLC fingerprint of Tibetan medicine Shaji Gao from different habitats and lay a foundation for Shaji Gao varieties identification and preparation process. The chromatographic condition was as follow: Agilent zorbax SB-C18 (4.6 mm x 250 mm, 5 μm) eluted with the mobile phases of acetonitrile and 0.4% phosphoric acid water in gradient mode. The flow rate was 1.0 mL x min(-1), and the detection wavelength was set at 360 nm. The fingerprints of 15 batches Shaji Gao were carried out by similarity comparation, 7 chromatographic peaks were extracted as the common peaks of fingerprint, 3 peaks were identified, which were quercetin, kaempferol and isorhamnetin. The similarity degrees of 14 batches of samples were above 0.9 and 1 batch of samples was below 0.9. This is the first established fingerprint of Shaji Gao by using HPLC. This method has good precision, stability and repeatability that it could provide basis for quality control and evaluation of Shaji Gao.

Concentrations of 20 free amino aicds (FAAs) in a famous Tibetan medicine Gentiana dahurica was first investigated using 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC) as the pre-column fluorescence derivatization reagent by reversed-phase high performance liquid chromatography (RP-LC). 20 amino acid derivatives (AAD) were separated on a Hypersil BDS C<sub>18</sub> column with a good baseline resolution within 65 min. Identification of 20 AAD was by online post-column mass spectrometry with an electrospray ionization (ESI) source. The validation of the method was examined by linearity, repeatability, and detection limits. Most linear correlation coefficients for AAD were &gt;0.9990, and detection limits (at signal-to-noise of 3:1) were 6.5-178.2 fmol. There were 18 FAAs found in G. dahurica, of which seven FAAs were necessary to the people's health and related to the treatment of liver and gall disease. Variation of concentrations of the 20 FAAs showed geographical distribution difference among populations. Meanwhile a stable genetic diversity of FAAs composition of G. dahurica was also revealed at the species level. Results of the present study proved that the established method was rapid and reproducible for further separation and determination of FAAs in more medicinal plants.

<br>Display Omitted<br>• A new coupled method of stable isotope-labeling derivatization with UA-DLLME was reported. • Simultaneous determination of multiple neurotransmitters with UHPLC-MS/MS. • Heavy labeled d3-MASC standards were used as the internal standards for quantification. • The method was sensitive, accurate and low matrix effect. • Application for neurotransmitters dynamic changes in rats brain microdialysates.<br>In this work, for the first time, a new hyphenated technique of stable isotope-labeling derivatization-ultrasound-assisted dispersive liquid-liquid microextraction has been developed for the simultaneous determination of monoamine neurotransmitters (MANTs) and their biosynthesis precursors and metabolites. The developed method was based on ultra high performance liquid chromatography tandem mass spectrometry detection using multiple-reaction monitoring mode. A pair of mass spectrometry sensitizing reagents, d0-10-methyl-acridone-2-sulfonyl chloride and d3-10-methyl-acridone-2-sulfonyl chloride, as stable isotope probes was utilized to facilely label neurotransmitters, respectively. The heavy labeled MANTs standards were prepared and used as internal standards for quantification to minimize the matrix effects in mass spectrometry analysis. Low toxic bromobenzene (extractant) and acetonitrile (dispersant) were utilized in microextraction procedure. Under the optimized conditions, good linearity was observed with the limits of detection (S/N > 3) and limits of quantification (S/N > 10) in the range of 0.002-0.010 and 0.015-0.040 nmol/L, respectively. Meanwhile, it also brought acceptable precision (4.2-8.8%, peak area RSDs %) and accuracy (recovery, 96.9-104.1%) results. This method was successfully applied to the simultaneous determination of monoamine neurotransmitters and their biosynthesis precursors and metabolites in rat brain microdialysates of Parkinson's disease and normal rats. This provided a new method for the neurotransmitters related studies in the future.

A new fluorescent labeling reagent has been developed for the determination of fatty acids (FAs) by HPLC with fluorescence detection. The derivatization conditions including the amount of derivatization reagent, temperature, and type of catalyst were investigated, the results indicated that the reaction proceeded within 30 min at 90°C in the presence of K₂CO₃ catalyst. The maximal yield was obtained with a four- to fivefold molar reagent excess. The derivatives exhibited strong fluorescence with an excitation maximum at <i>λ</i><sub>ex</sub> = 245 nm and an emission maximum at <i>λ</i><sub>em</sub> = 410 nm. Twenty-five FA derivatives were well separated by RP-HPLC on a Hypersil BDS C₈ column in combination with gradient elution. All FAs were found to give excellent linear responses with correlation coefficients >0.9992. The method gave a low LOQ of 0.85-5.5 ng/mL (S/N of 10). The developed method was employed to analyze free FAs (FFAs) composition in pomegranate samples without any purification. FFAs in samples were doubly identified by HPLC retention time and protonated molecular ion corresponding to <i>m</i>/<i>z</i> [M+H]⁺. This newly developed method allows a highly sensitive determination of trace FFAs from pomegranate and other foodstuffs.

The goal of the presented work is to develop a simple and sensitive high-performance liquid chromatography in combination with fluorescence detection (HPLC-FLD) method for the determination of four nitrofurans (NFs) metabolites compounds (semicarbazide (SEM), 1-aminohydantoin (AH), 3-amino-2-oxazolidinone (AOZ) and 3-amino-morpholinomethyl-2-oxazolidinone (AMOZ)) in foodstuffs. For this goal, we synthesized a novel fluorescence labeling reagent, 4-(carbazole-9-yl)-benzyl chloroformate (CBBC) to label NFs metabolites compounds. NFs metabolites compounds can be labeled rapidly only within 5 min at the room temperature (25 °C). The labeled derivatives showed excellent fluorescence property with maximum excitation and emission wavelengths of 375 nm and 410 nm, respectively. The labeled derivatives were analyzed on a reversed-phase Eclipse XDB-C18 column within 10 min. Excellent linearity (R2 > 0.995) of all NFs metabolites compounds was achieved with the limits of detection (LODs) and the limits of quantitations (LOQs) in the low micrograms per kilogram range of 0.20-0.30 μg·kg−1 and 0.70-1.00 μg·kg−1, respectively. Satisfactory recoveries in the range of 92.5-98.0% were obtained for all NFs metabolites compounds. Using the proposed HPLC-FLD method, we successfully determined four NFs metabolites compounds in different foodstuffs. As promising, this highly sensitive and reliable method would also be extended for the quantitation of NFs metabolites compounds in other samples.<br><br>Display Omitted<br>• A novel fluorescence labeling reagent CBBC was synthesized to label nitrofurans (NFs) metabolites compounds. • A pre-column derivatization HPLC-FLD method was developed for the determination of NFs metabolites compounds in foodstuffs. • LODs were in the low micrograms per kilogram range of 0.2-0.3 μg·kg-1.

A novel high-performance liquid chromatography-fluorescence analysis in combination with in situ degradation-derivatization (ISD-D) technique was developed for simultaneous determination of seven organophosphorus thioester pesticides (OPTPs) in tea. The ISD-D technique was based on degradation of OPTPs by a nucleophilic substitution reaction between phenylbutane-1,2,3-trione-2-oxime and OPTPs, which can give thiol degradation products (DPs). The thiol DPs obtained were derivatized with the novel derivatization reagent N-(4-(carbazole-9-yl)-phenyl)-N-maleimide (NCPM) in a syringe. Attractively, NCPM itself did not fluoresce, whereas the derivatives of the thiol DPs fluoresced intensely, with excitation and emission maxima at 290 nm and 368 nm, respectively, which extraordinary reduced the background interference and increased the detection sensitivity for thiol DPs. Excellent linearity (R2 > 0.995) for all OPTPs was achieved, with limits of detection and limits of quantitation ranging from 0.23 to 0.45 μg/kg and from 0.75 to 1.43 μg/kg, respectively. Satisfactory recoveries ranging from 90.5% to 96.0% were obtained for all OPTPs. The ISD-D technique provided a novel and sensitive strategy for quantitation of trace amounts of OPTPs in real samples. Graphical abstract ᅟ.

A stable, effective, sensitive and selective method for simultaneous determination of 11 aldehydes in foodstuffs using a novel fluorescence-labeling reagent 2-(12-benzo[<i>b</i>]acridin-5-(12<i>H</i>)-yl)-acetohydrazide (BAAH) has been developed by HPLC with fluorescence detection and mass spectrometric identification. Response surface methodology was employed to optimize the derivatization reaction between BAAH and aldehydes. The completed separation of the 11 aldehydes was achieved in as little as 18 min on a reversed-phase Hypersil BDS C<sub>8</sub> column with aqueous acetonitrile as mobile phase in conjunction with a binary gradient elution. Excellent linear coefficients were found to be of >0.9994. This method also showed excellent reproducibility and offered the low detection limits of 0.21-0.58 nM (at a signal-to-noise ratio of 3). The developed method was successfully applied to analyze aldehydes in various foodstuffs and exhibited satisfactory applicability.

High-speed counter-current chromatography (HSCCC) was successfully applied to the isolation and purification of four xanthone glycosides from Halenia elliptica, a plant widely used in traditional Tibetan medicine. The introduction of HSCCC greatly improved the efficiency of compounds preparation from Halenia elliptica. The following were obtained from 100 mg of crude sample in one-step separation: 2.5 mg of 1-O-primeverosyl-2,3,4,5,7-pentamethoxyxanthone, 7.0 mg of 1-O-primeverosyl-2,3,4,7- tetramethoxyxanthone, 10.0 mg of 1-O-primeverosyl-2,3,5-trimethoxyxanthone (demethyoxyhaleniaside), and 8.5 mg of 1-O-primeverosyl-2,3,4,5-tetramethoxyxanthone. HPLC analysis showed that each target compound had a purity of over 98%, and UV, 1H NMR, and 13C NMR data confirmed the component chemical structures.

High-speed counter-current chromatography (HSCCC) was successfully applied for the first time to isolate and purify four cis-trans isomers of coumaroylspermidine analogs from Safflower. HSCCC separation was achieved with a two-phase solvent system composed of chloroform-methanol-water (1:1:1, v/v/v) with the upper phase as the mobile phase. In a single run, a total of 1.3mg of N(1), N(5), N(10)-(E)-tri-p-coumaroylspermidine (EEE), 4.4mg of N(1)(E)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (EZE), 7.2mg of N(1)(Z)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (ZZE), and 11.5mg of N(1),N(5),N(10)-(Z)-tri-p-coumaroylspermidine (ZZZ) were obtained from 100mg of crude sample. High Performance Liquid Chromatography (HPLC) analysis showed that the purities of these four components are 95.5%, 98.1%, 97.5% and 96.2%, respectively. The chemical structures were identified by ESI-MS, (1)H NMR and (13)C NMR.

Introduction: Xanthones, the primary constituents of <i>Swertia mussotii</i>, are known to possess a variety of biological activities, including anti-depressant, anti-leukaemic, anti-tumour, anti-tubercular, choleretic, diuretic, anti-microbial, anti-fungal, anti-inflammatory, anti-viral, cardiotonic and hypoglycemic properties. However, high performance, environmentally friendly methods for isolating and purifying xanthones from <i>S. mussotii</i> are not currently available.<br>Objective: To develop a high performance and environmentally friendly method for the preparative separation of xanthones methylswertianin, swerchirin and decussatin from <i>S. mussotii</i> using high-speed counter-current chromatography (HSCCC).<br>Methodology: A solvent system composed of <i>n</i>-hexane:ethyl acatate:methanol:water (5:5:10:4, v/v/v/v) was developed for the separation method. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase at a flow rate of 1.5 mL/min, a rotation speed of 800 rpm and a temperature of 25 °C.<br>Results: Using the described method, 8 mg of methylswertianin, 21 mg of swerchirin and 11 mg of decussatin with purities of over 98% could be isolated from a 150 mg crude sample. They were identified by ¹H-NMR and <sup>13</sup> C-NMR analysis.<br>Conclusion: Three xanthones in <i>Swertia mussotii</i> could be systematically isolated and purified using HSCCC. Copyright © 2011 John Wiley & Sons, Ltd.

OBJECTIVES: To investigate the protective effect of Herpetospermum pedunculosum (H. pedunculosum) seed oil against carbon tetrachloride (CCl4)-induced liver damage.METHODS: This experimental study was conducted at the Northwest Institute of Plateau Biology, Chinese Academy of Sciences, and Yantai University, China from November 2012 to May 2013. The H. pedunculosum seed oil was extracted using supercritical carbon dioxide. The antioxidant activities of H. pedunculosum seed oil were assayed in vitro by 2,2-diphenyl-1-picrylhydrazyl assay, lipid peroxidation assay, and antihemolytic assay. Adult Sprague Dawley rats were randomly divided into 6 groups (10 rats/group) including control, CCl4, CCl4+bifendate, and CCl4+H. pedunculosum seed oil (3 different doses) groups. RESULTS: The CCl4-induced liver lesions include hepatocyte necrosis, ballooning degeneration, calcification, and fibrosis. Moreover, CCl4 damage results in an obvious increase of serum triglycerides, high-density lipoprotein, low-density lipoprotein, malondialdehyde, total bilirubin, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase activity. In addition, CCl4 also significantly decreased the activities of superoxide dismutase (SOD). By contrast, H. pedunculosum seed oil administration significantly ameliorated the CCl4-induced liver lesions, lowered the serum levels of hepatic enzyme markers, and increased the activities of SOD. CONCLUSION: The results of this study show that H. pedunculosum seed oil can be proposed to protect the liver against CCl4-induced oxidative damage in rats, and the hepatoprotective effect might be correlated with its potent antioxidant and free radical scavenging effect.

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