<b>Caragana korshinskii</b> Kom. (CK), one of afforestation tree species, is widely planted in northwest region of China. To compare the constituents as references for further utilization of CK, <b>C. microphyll</b> Lam. (CM) and <b>C. jubata</b> L. (CJ), been used as traditional Chinese medicine, were taken into consideration. To obtain more information on CK for further utilization, a sensitive and stable pre-column derivatization method for the analysis of fatty acids (FAs) was established using a novel labeling reagent 2-(5H-benzo[a]-carbazol-11(6H)-yl)ethyl hydrazine-carboxylate (BCEHC) by HPLC with fluorescence detector. The derivatives exhibit predominant fluorescence property at excitation and emission wavelengths of 330 nm and 380 nm, respectively. 16 derivatives of FAs including 13 saturated FAs and 3 unsaturated FAs are separated on a reversed-phase column with gradient elution within 30 min. The validation of method indicated that all FAs were given excellent linear responses with good linear coefficient of correlation being equal to or greater than 0.9985. The limits of detection (LODs) at a signal-to-noise ratio of 3 varied from 63.12 to 116.21 ng L−1. The developed method was successfully applied to determine the contents of free FAs (FFAs) in flowers, leaves and bark of CK and the samples were extracted by a green and simple method of gas purge microsyringe extraction. The results show that the contents of linoleic acid and linolenic acid are high in flowers and leaves while the bark is rich in linoleic acid. The total content of FFAs in all parts of CK is higher than that of CM. The distribution of FFAs in plants is obviously different even in the congeneric among different species.
A method of using high-speed counter-current chromatography (HSCCC) and semi-preparative reversed-phase liquid chromatography (semi-preparative RPLC) to preparatively separate flavone glucosides and lignan from the crude extracts of <i>Caragana korshinskii</i> has been established for the first time in this study. Five flavone glucosides, including 9 mg of kaempferol 3-O-{β-<i>d</i>-glucopyranosyl(1→2)-[α-<i>l</i>-rhamonopyranosyl(1 → 6)]-β-<i>d</i>-galactopyranoside}, 21 mg of kaempferol 3-O-α-<i>l</i>-rhamnopyranosyl(1→6)-β-<i>d</i>-galactopyranoside-7-O-α-<i>l</i>-rhamnopyranoside, 34 mg of kaempferol 3-O-β-<i>d</i>-galactopyranoside-7-O-α-<i>l</i>-rhamnopyranoside, 27 mg of kaempferol 3-O-β-<i>d</i>-glucopyranosyl-7-O-α-<i>l</i>-rhamnopyranoside, and 14 mg of calycosin 7-O-β-<i>d</i>-glucopyranoside, and one lignan, 16 mg of alangilignoside B, were successfully isolated from 1.8 g of the crude sample through the combination of HSCCC with a two-phase solvent system composed of ethyl acetate-<i>n</i>-butanol-0.5 % formic acid (4:1:5, <i>v/v/v</i>) and semi-preparative RPLC with a mobile phase of methanol-water (20:80, <i>v/v</i>). The purities of the six compounds are all over 95 % as determined by HPLC and the structures are confirmed by the analysis of UV, <sup>1</sup>H-NMR, and <sup>13</sup>C-NMR and compared with published data.
A method of using high-speed counter-current chromatography (HSCCC) for preparative isolation and purification of oligostilbenes from the ethanol extracts of seed kernel of Iris lactea Pall. var. chinensis (Fisch.) Koidz was established in this study. Four oligostilbenes were successfully separated and purified by HSCCC with two sets of two-phase solvent system, n-hexane-ethyl acetate-methanol-water (3:6:4.2:5.5, v/v/v/v) in the head-to-tail elution mode for the first separation to mainly isolate vitisin A (58 mg), ɛ-viniferin (76 mg) and peak II (43 mg) from 300 mg of the crude ethanol extracts, and then light petroleum-ethyl acetate-methanol-water (5:5:3:6, v/v/v/v) in the tail-to-head elution mode for the second separation to isolate vitisin B (52 mg) and vitisin C (11 mg) from 100mg of peak II. The purities of the isolated four oligostilbenes were all over 95.0% as determined by HPLC. Vitisin A, vitisin B and vitisin C, resveratrol tetramers, were isolated from Iris lactea for the first time. The preparation of crude sample was simple and the HSCCC method for the isolation and purification of four oligostilbenes was rapid, efficient and economical.
A simple, sensitive and selective method based on one-step fluorescence labeling and ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) was developed for the determination of biogenic amines (BAs) in foodstuff samples by high-performance liquid chromatography (HPLC) with fluorescence detection (FLD). In this work, fluorescence probe 2-(11H-benzo[a]carbazol-11-yl) ethyl carbonochloridate (BCEC-Cl) was applied to label BAs. What followed was the UA-DLLME procedure that was carried out using chloroform and acetone as extraction and disperser solvents, respectively. A response surface methodology (RSM) based on a Box-Behnken design (BBD) was employed to optimize the main parameters affecting the fluorescence labeling and DLLME efficiency. Under the optimal conditions, this method offered low limits of detection (LODs) of 1.1-7.8 ng/mL and limits of quantification (LOQs) of 3.5-26.1 ng/mL. Finally, the method was successfully used for the determination of trace BAs in real samples and exhibited powerful potential in the high-throughput sample screening.
<br>• A DLLME/HPLC-FLD method for triterpenic acid determination was developed. • DLLME was firstly used for preconcentration of triterpenic acids in medicinal herbs. • This method was sensitive and selective for triterpenic acid analysis. • A new derivatization reagent for triterpenic acid has been synthesized.<br>A novel analytical method was developed for simultaneous determination of six triterpenic acids using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) follow by high-performance liquid chromatography (HPLC) with fluorescence detection. Six triterpenic acids (ursolic acid, oleanolic acid, betulinic acid, maslinic acid, betulonic acid and corosolic acid) were extracted by UA-DLLME using chloroform and acetone as the extraction and disperser solvents, respectively. After the extraction and nitrogen flushing, the extracts were rapidly derivatized with 2-(12,13-dihydro-7H-dibenzo[a,g]carbazol-7-yl)ethyl4-methylbenzenesulfonate. The main experimental parameters affecting extraction efficiency and derivatization yield were investigated and optimized by response surface methodology (RSM) combined with Box-Behnken design (BBD). The limits of detection (LODs) and the limits of quantification (LOQs) were in the range of 0.95-1.36 ng mL−1 and 3.17-4.55 ng mL−1, respectively. Under the optimum conditions, the method has been successfully applied for the analysis of triterpenic acids in six different traditional Chinese medicinal herbs.
• Extracts from <b>Lycium ruthenicum</b> Murr. fruit were obtained by UAE. • Phenolic compounds and antioxidant activities of obtained extracts were simultaneously optimized by RSM. • Optimum parameters: time 30 min, power 100 W, solvent-sample ratio 40 mL/g, ethanol 33%. • The extracts contained phenolic acids, identified and quantified by HPLC.<br><b>Lycium ruthenicum</b> Murr. (LR) is a functional food that plays an important role in anti-oxidation due to its high level of phenolic compounds. This study aims to optimize ultrasound-assisted extraction (UAE) of phenolic compounds and antioxidant activities of obtained extracts from LR using response surface methodology (RSM). A four-factor-three-level Box-Behnken design (BBD) was employed to discuss the following extracting parameters: extraction time (<b>X</b> 1), ultrasonic power (<b>X</b> 2), solvent to sample ratio (<b>X</b> 3) and solvent concentration (<b>X</b> 4). The analysis of variance (ANOVA) results revealed that the solvent to sample ratio had a significant influence on all responses, while the extraction time had no statistically significant effect on phenolic compounds. The optimum values of the combination of phenolic compounds and antioxidant activities were obtained for <b>X</b> 1 = 30 min, <b>X</b> 2 = 100 W, <b>X</b> 3 = 40 mL/g, and <b>X</b> 4 = 33% (v/v). Five phenolic acids, including chlorogenic acid, caffeic acid, syringic acid, <b>p</b>-coumaric acid and ferulic acid, were analyzed by HPLC. Our results indicated that optimization extraction is vital for the quantification of phenolic compounds and antioxidant activity in LR, which may be contributed to large-scale industrial applications and future pharmacological activities research.
Lycium ruthenicum Murr. (LR) is a functional food that plays an important role in anti-oxidation due to its high level of phenolic compounds. This study aims to optimize ultrasound-assisted extraction (UAE) of phenolic compounds and antioxidant activities of obtained extracts from LR using response surface methodology (RSM). A four-factor-three-level Box-Behnken design (BBD) was employed to discuss the following extracting parameters: extraction time (X1), ultrasonic power (X2), solvent to sample ratio (X3) and solvent concentration (X4). The analysis of variance (ANOVA) results revealed that the solvent to sample ratio had a significant influence on all responses, while the extraction time had no statistically significant effect on phenolic compounds. The optimum values of the combination of phenolic compounds and antioxidant activities were obtained for X1=30min, X2=100W, X3=40mL/g, and X4=33% (v/v). Five phenolic acids, including chlorogenic acid, caffeic acid, syringic acid, p-coumaric acid and ferulic acid, were analyzed by HPLC. Our results indicated that optimization extraction is vital for the quantification of phenolic compounds and antioxidant activity in LR, which may be contributed to large-scale industrial applications and future pharmacological activities research.
• In situ derivatization-UADLLME was firstly reported for NTs in rat brain microdialysates. • Lissamine rhodamine B sulfonyl chloride was firstly used as derivatization reagent. • The method was simple, rapid, green, efficient, sensitive and low matrix effect. • This method was successfully applied for Parkinson’s rat brain microdialysates.<br>Simultaneous monitoring of several neurotransmitters (NTs) linked to Parkinson’s disease (PD) has important scientific significance for PD related pathology, pharmacology and drug screening. A new simple, fast and sensitive analytical method, based on in situ derivatization-ultrasound-assisted dispersive liquid-liquid microextraction (in situ DUADLLME) in a single step, has been proposed for the quantitative determination of catecholamines and their biosynthesis precursors and metabolites in rat brain microdialysates. The method involved the rapid injection of the mixture of low toxic bromobenzene (extractant) and acetonitrile (dispersant), which containing commercial Lissamine rhodamine B sulfonyl chloride (LRSC) as derivatization reagent, into the aqueous phase of sample and buffer, and the following in situ DUADLLME procedure. After centrifugation, 50 μL of the sedimented phase (bromobenzene) was directly injected for ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) detection in multiple reaction monitoring (MRM) mode. This interesting combination brought the advantages of speediness, simpleness, low matrix effects and high sensitivity in an effective way. Parameters of in situ DUADLLME and UHPLC-MS/MS conditions were all optimized in detail. The optimum conditions of in situ DUADLLME were found to be 30 μL of microdialysates, 150 μL of acetonitrile containing LRSC, 50 μL of bromobenzene and 800 μL of NaHCO3-Na2CO3 buffer (pH 10.5) for 3.0 min at 37 °C. Under the optimized conditions, good linearity was observed with LODs (S/N > 3) and LOQs (S/N > 10) of LRSC derivatized-NTs in the range of 0.002-0.004 and 0.007-0.015 nmol/L, respectively. It also brought good precision (3.2-12.8%, peak area CVs%), accuracy (94.2-108.6%), recovery (94.5-105.5%) and stability (3.8-8.1%, peak area CVs%) results. Moreover, LRSC derivatization significantly improved chromatographic resolution and MS detection sensitivity of NTs when compared with the reported studies through the introduction of a permanent charged moiety from LRSC into NTs. Taken together, this in situ DUADLLME method was successfully applied for the simultaneous determination of six NTs in biological samples.
Glucose carbon microspheres have been widely used for wastewater treatment as adsorbent owing to their strong adsorption capacity, but for large-scale applications, the glucose carbon microspheres are inconvenient to be recycled from aqueous suspension due to their good suspendability. Moreover, the primitive nature of small particle size, large specific surface area and high surface energy of glucose carbon microspheres make them prone to aggregate and thus, disperse no-effectively for the other extended application. To solve this dilemma, polyester (PET) fibers decorated with glucose carbon microspheres (GC@PFs) were herein fabricated by one-step hydrothermal carbonization with acrylic acid as a coupling agent. The products were characterized by Fourier Transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Boehm titration, X-ray diffraction (XRD), Thermo-gravimetric Analysis (TG), Scanning Electron Microscope (SEM) and zeta potential respectively. The experimental results showed that a large amount of glucose carbon microspheres were evenly dispersed on the surface of carboxyl activated polyester fibers with uniform particle diameter, and the composite fibers showed desirable adsorption ability of cationic dyes for its more negative zeta potential. The dye adsorption isotherm follows Langmuir model and pseudo-second-order kinetic model better. Remarkably, the adsorbent has an excellent recyclability for maintaining a high removal rate (>85%) to dye even after 10 cycles.<br>• Glucose carbon microspheres were evenly distributed on the PET fibers surface that solved the problem of easy aggregation. • The polyester fibers were firstly decorated with glucose carbon microspheres through one-step hydrothermal carbonization. • Acrylic acid maintained the integrity of PET fabric and introduced a quite number of carboxyl groups on the PET surface. • The surface decorated composite material possessed good adsorption property and easy recovery performance. • The glucose carbon microspheres decorated polyester fibers showed a highly selective adsorption for the cationic dyes.
<br>Display Omitted<br>• A new protocol of synchronous determination of phenolic acids (PAs) was proposed by RP-HPLC-UV with double-wavelength. • The validated results demonstrated that the proposed method was feasible to determine PAs in plant samples. • The protocol was applied for analysis PAs in <b>Caragana korshinskii</b> Kom. which was mainly rich in chlorogenic acid, vanillic acid, caffeic acid and rosmarinic acid. • Total content of PAs in leaves was the highest compared with that of flowers and bark.<br>The utilization of <b>Caragana korshinskii</b> Kom. (CK) is currently concentrated on its ecological and fuel functions. Little attention has been devoted to the analysis of their phenolic acid (PA) components. To obtain more data for further utilization of CK, a new analysis protocol was tested to determine PAs synchronously by RP-HPLC-UV with double-wavelength (280 nm and 320 nm) detection. Specifically, separation of PA components was performed on a Hypersil Gold C18 reverse phase column with gradient elution. A four-factor-three-level Box-Behnken design was implemented for optimization of PA extraction. The results demonstrated that CK were rich primarily in chlorogenic acid, vanillic acid, caffeic acid and rosmarinic acid. The total content of PAs in CK leaves was the highest compared with its other parts. The distribution of total flavonoid content of CK was leaves > flowers > bark, while that of the total phenolic content of CK was flowers > leaves > bark.
Two novel organic amide alkaloids, 4-[(<i>E</i>)-<i>p</i>-coumaroylamino]butan-1-ol (<b>1</b>) and 4-[(<i>Z</i>)-<i>p</i>-coumaroylamino]butan-1-ol (<b>2</b>), together with a rare pyridoindole alkaloid, hippophamide (<b>3</b>), were isolated from the seed residue of <i>Hippophae rhamnoides</i> Linn. subsp. <i>sinensis</i> Rousi. Their structures were determined by spectroscopic means. The results show that compounds <b>1</b> and <b>2</b> are (<i>E</i>/<i>Z</i>)<i>-</i>isomers, compound <b>3</b>, a pyridoindole alkaloid concerted with <i>γ</i>-lactam ring.
A new triterpenoid, namely myricarin C (compound 1), together with three known compounds myricarin A (compound 2) and myricarin B (compound 3), 3α-hydroxy-D-friedoolean-14-en-28-oic acid (compound 4), was isolated from the overground part of Myricaria squamosa. Compound 2 and compound 3 existed in the solution by the form of cis-trans isomers. Their structures were elucidated by means of extensive spectroscopic methods, including 1D-NMR, 2D-NMR, and HR-ESI-MS. The antioxidant properties of all compounds were calculated based on the DPPH radical scavenging activities. Results showed that myricarin A and myricarin C had general antioxidant activities with EC50 values of 40.90 μg/ml, 42.22 μg/ml, respectively, compared to the control, rutin (5.17 μg/ml). The EC50 values of myricarin B was 195.81 μg/ml. Compound 4 had no antioxidant activities.
A new triterpenoid, namely myricarin C (compound 1), together with three known compounds myricarin A (compound 2) and myricarin B (compound 3), 3α-hydroxy-D-friedoolean-14-en-28-oic acid (compound 4), was isolated from the overground part of Myricaria squamosa. Compound 2 and compound 3 existed in the solution by the form of cis-trans isomers. Their structures were elucidated by means of extensive spectroscopic methods, including 1D-NMR, 2D-NMR, and HR-ESI-MS. The antioxidant properties of all compounds were calculated based on the DPPH radical scavenging activities. Results showed that myricarin A and myricarin C had general antioxidant activities with EC50 values of 40.90 μg/ml, 42.22 μg/ml, respectively, compared to the control, rutin (5.17 μg/ml). The EC50 values of myricarin B was 195.81 μg/ml. Compound 4 had no antioxidant activities.
Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.
Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.
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