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Summary: To improve the utilisation of abomasum and explore the material basis of its antioxidant and hyaluronidase inhibitory activities, a homogeneous protein RDA4‐1 was isolated from the abomasum of cultured red deer by two‐step chromatography process for the first time in this study. It has a molecular weight of 15 kDa and comprises 43.56% essential amino acids. RDA4‐1 scavenged 50.97% of DPPH• and 88.37% of ABTS+· at 1.5 mg mL−1, and inhibited hyaluronidase by 79.23% at 1 mg mL−1. The CD and fluorescence spectroscopy was used to initiate explore the hyaluronidase inhibition reaction process. With an increase in the concentration of RDA4‐1 in the inhibition reaction, the wavelength of the negative peak of CD shifted from 208 to 218 nm, and the absorption of the positive peak of CD increased from 0.5 to 8.3 mdeg. Furthermore, fluorescence absorption at a wavelength of 340 nm rose from 248 to 762 au. These findings suggest that the interaction of RDA4‐1 with hyaluronidase induces alterations in the secondary structure of the protein complex, and RDA4‐1 binds reversibly to the enzyme in a non‐covalent manner. The results of this study indicate that RDA4‐1 could serve as a potential hyaluronidase inhibitor in the development of nutraceuticals. [ABSTRACT FROM AUTHOR]

The Yanqi black mushroom is a new wild mushroom resource distributed in Central Asia and in China, it is only present in Xinjiang Province. The goal of this study was to determine the chemical composition and antioxidant properties of this mushroom. Based on dry weight, Yanqi black mushroom contained 15.1% ash, 1.68% fat, 1.09% crude polysaccharide, 34.15% protein, 19.62% amino acid, 6.98% essential amino acid, 3.51% mannitol, and 0.75% total phenols. Further, linoleic acid accounted for 87.3% of total fatty acid. The amino acids Glu, Ala, Leu, and Phe amounted to 4.13%, 1.84%, 1.28%, and 0.96% respectively. Methanol extracts were able to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) by 97% at 1.2 mg/ml and 2,2-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid diammonium salt (ABTS+) by 99.62% at 0.64 mg/ml. EC50values for anti-oxidation in the presence of DPPH and ABTS+were 0.127 mg/ml and 0.119 mg/ml, respectively. In summary, Yanqi black mushroom was not only a high-protein and low-fat health food but also a natural antioxidant resource. [ABSTRACT FROM PUBLISHER]

An efficient method was developed and established for the rapid analysis of a traditional Uighur medicinal prescription, Yizhihao granule, by liquid chromatography-Quadrupole time-of-flight tandem mass spectrometry. HPLC was performed with a Poroshell 120-EC18 column with 2.7 µm particle size using A gradient elution system. A quadrupole time-of-flight analyzer was used for the determination of accurate mass of the protonated or deprotonated molecules and fragment ions. Sixty-six constituents including amino acids, organic acids (aliphatic acids, benzoic acid derivatives, and chlorogenic acids), alkaloids (indole and quinazolinone type), flavonoids (C,O-glycoside, C-glycosides, O-glycosides, and aglycone), sesquiterpenoids (rupestonic acid derivatives), and other compounds were identified or tentatively characterized in Yizhihao granule as a presented application of prescription according to the accurate mass, MS/MS data, and relevant literature. Additionally, the fragmentation pathways of two rupestonic acid derivatives were proposed. The relationship between structure features and fragmentation patterns were investigated thoroughly and applied in the on-line analysis to deduce the composition of traditional Uighur herbal prescription. The present method and results should be beneficial in the development of traditional Uighur herbal prescription. [ABSTRACT FROM PUBLISHER]

A novel ellipsoid column was designed for centrifugal counter-current chromatography. Performance of the ellipsoid column with a capacity of 3.4 mL was examined with three different solvent systems composed of 1-butanol–acetic acid–water (4:1:5,v/v/v) (BAW), hexane–ethyl acetate–methanol-0.1 M HCl (1:1:1:1,v/v/v/v) (HEMH), and 12.5% (w/w) PEG1000 and 12.5% (w/w) dibasic potassium phosphate in water (PEG-DPP) each with suitable test samples. In dipeptide separation with BAW system, both stationary phase retention (Sf) and peak resolution (Rs) of the ellipsoid column were much higher at 0° column angle (column axis parallel to the centrifugal force) than at 90° column angle (column axis perpendicular to the centrifugal force), where elution with the lower phase at a low flow rate produced the best separation yielding Rs at 2.02 with 27.8% Sf at a flow rate of 0.07 mL/min. In the DNP-amino acid separation with HEMW system, the best results were obtained at a flow rate of 0.05 ml/min with 31.6% Sf yielding high Rs values at 2.16 between DNP-DL-glu and DNP-β-ala peaks and 1.81 between DNP-β-ala and DNP-L-ala peaks. In protein separation with PEG-DPP system, lysozyme and myolobin were resolved at Rs of 1.08 at a flow rate of 0.03 mL/min with 38.9% Sf. Most of those Rs values exceed those obtained from the figure-8 column under similar experimental conditions previously reported. [ABSTRACT FROM PUBLISHER]

High performance liquid chromatography coupled with electrospray ionization quadrupole-time-of-flight tandem mass spectrometry was used to profile the phenylethanoid glycosides inLagotis brevituba. A total of twenty-three phenylethanoid glycosides were characterized by comparing the retention time and fragmentation with standards, accurate mass measurements, and fragmentation at low and high collision energies. Most phenylethanoid glycosides were reported inL. brevitubafor the first time. This established method may be employed for comprehensive quality control ofL. brevituba. [ABSTRACT FROM AUTHOR]

An effective high-speed countercurrent chromatography (HSCCC) method was established for separation and purification of (S)-dehydrovomifoliol from the leaves ofNitraria sibiricaPall. (NS). HSCCC was performed with a two-phase solvent systems composed of n-hexane-ethyl acetate-methanol-water (1:5:1:5, v/v) at a flow rate of 2 mL/min. From 1 g crude sample of NS, 23 mg (S)-dehydrovomifoliol was obtained at purity of 95%. The chemical structure was confirmed by MS,1H NMR, and13C NMR. (S)-dehydrovomifoliol was isolated fromNitrariagenus for the first time. [ABSTRACT FROM AUTHOR]

An effective high-speed countercurrent chromatography (HSCCC) method was established for further separation and purification of four minor flavonols in addition to five major flavonols which were reported by our previous study from extracts of Flos gossypii. HSCCC was performed with three two-phase solvent systems composed of n-hexane-ethyl acetate-methanol-water (7.5:15:6:7, v/v), (2.5:15:2:7, v/v), and (0:1:0:1, v/v). The separation was repeated three times, and 3.8 mg of 8-methoxyl-kaempferol-7-O-β-D-rhamnoside (HPLC purity 98.27%), 6.7 mg of astragalin (HPLC purity 94.18%), 3.3 mg of 4'-methoxyl-quercetin-7-O-β-D-glucoside (HPLC purity 94.30%), and 8.2 mg of hyperoside (HPLC purity 93.48%) were separated from 150 mg of the crude sample. The chemical structures of the flavonols were confirmed by MS, 1H NMR, and 13C NMR. Meanwhile, the results indicated that the target compound with smaller K value (<0.5) can be separated by increasing column length of HSCCC. And, four separation rules of flavonols were established according to the present study and references were summarized, which can be used as a useful guide for separation of flavonols by HSCCC. [ABSTRACT FROM AUTHOR]

The conventional toroidal coil in centrifugal countercurrent chromatography has a low level of stationary phase retention, since a half of each helical turn is entirely occupied by the mobile phase. In order to cope with this problem, several new column designs including zigzag, saw-tooth, and figure-8 patterns have been introduced, and their performance was compared in terms of retention of the stationary phase (Sf), peak resolution (Rs), theoretical plate number (N), and column pressures. Overall results of experiments indicate that the figure-8 column yields the highest Rs when the lower phase is used as the mobile phase. Since the column pressure of all these new columns are much lower than that in the traditional toroidal coil column, the separation efficiency can be improved using a long separation column without a risk of column damage by high back pressure. [ABSTRACT FROM AUTHOR]

The toroidal coil using an equilateral triangular core and zigzag pattern column have improved both retention of the stationary phase and peak resolution of the conventional toroidal coil in centrifugal counter-current chromatography. To further improve the retention of stationary phase and peak resolution, a novel saw tooth column was designed and the performance of the system was evaluated at various flow rates. The results indicated that both retention of the stationary phase and peak resolution were improved as the flow rate was decreased and at a flow rate of 0.005 mL/min the resolution is remarkably increased. Modification of the tubing called flat-twisted tubing further improved the peak resolution without increasing the column pressure. With decreased column length at a capacity of about 0.2 mL, resolution of the saw tooth column was 1.02. [ABSTRACT FROM AUTHOR]

Imidazole, 1,2,4-triazole, indole, and benzotriazole undergo conjugate additions with α, β-unsaturated carbonyl compounds in the presence of anhydrous potassium phosphate at ambient temperature to afford the corresponding Michael adducts in excellent yields. [ABSTRACT FROM AUTHOR]

High-speed countercurrent chromatography (HSCCC) has been successfully used for the preparative isolation of flavonoids from the ethyl acetate extracts of black currant leaves. The HSCCC separation was performed with a two-phase solvent system composed of n-hexane/EtOAc/MeOH/H2O (1:10:1:10, v/v) at a flow rate of 1.5 mL/min. When the flow rate was increased from 1.0 to 3.0 mL/min, the retention of stationary phase decreased from 60.3% to 39.7% resulting in a loss of peak resolution, while the stationary phase retention is stable with an increase in sample size from 25 to 200 mg. From 100 mg of the crude sample, HSCCC separation yielded 4.0 mg of kaempferol 3-O-galactoside, 6.0 mg of kaempferol 3-O-glucoside, and 9.0 mg of fraction I containing a mixture of hyperoside and isoquercitrin. Then, from 18 mg of fraction I, 3.0 mg of hyperoside and 11.0 mg isoquercitrin were separated by preparative HPLC by successive sample injection at every 100 min interval. Chemical structures of all these compounds were confirmed by MS and NMR. [ABSTRACT FROM AUTHOR]

The toroidal columns using an equilateral triangular core, zigzag, and saw patterns has improved step by step both for retention of the stationary phase and peak resolution of the conventional toroidal coil in centrifugal countercurrent chromatography. To further improve the retention of stationary phase and peak resolution, a novel figure 8 toroidal coil was designed and the performance of the system was evaluated at various flow rates. In the figure-8 column with a capacity of 3 mL, the peak resolution of dipeptides (Val-Tyr and Trp-Tyr) was 1.63, and that of DNP-amino acids (DNP-DL-glu, DNP-β-ala, DNP-L-ala) were 1.92 and 1.85, respectively. The results indicated that retention of stationary phase and peak resolution were improved at lower flow rates. The Rs with lower mobile phase can be further increased by modifying the tubing to form a flat twisted configuration. With a decreased column length with a capacity of about 0.1 mL, resolution of the figure-8 column was 0.71 with about 40% retention of stationary phase at a flow rate of 0.005 mL/min. [ABSTRACT FROM AUTHOR]

The toroidal column using a zigzag pattern has been improved in both retention of the stationary phase and peak resolution. To further improve the retention of stationary phase and peak resolution, a series of novel geometric designs of tubing (plain, mid clamping, flattened, and flat twisted tubing) was evaluated for their performance in CCC. The results showed that the tubing, which was flattened vertically against the centrifugal force (vert-flattened tubing) produced the best peak resolution among them. Using vert-flattened tubing a series of experiments was performed to study the effects of column capacity and sample size. The results indicated that a 0.25 mL capacity column is ideal for analysis of small amount samples. [ABSTRACT FROM AUTHOR]

Black currant is an important material in the food industry, but little research has been reported on the isolation of phenolic acids because of their low content. In the present study, high-speed countercurrent chromatography (HSCCC) has been successfully used for the preparative isolation of the minor phenolic compounds from the ethyl acetate extracts of black currant fruit. The HSCCC separation was performed with a two phase solvent system composed of n-hexane/EtOAc/MeOH/H2O (5:15:4:7 v/v) at a flow rate of 1.5 mL/min. From a 500 mg crude sample 0.8 mg of protocatechuic acid, 1.0 mg of caffeic acid, 0.5 mg of 4-hydroxybenzoic acid, and 2.5 mg of myricetin were purified by a one step HSCCC operation,. Their chemical structures were confirmed by MS and NMR. [ABSTRACT FROM AUTHOR]

Chickpea is known as a plant that is rich in protein, carbohydrates, and nutrition, and its seeds and sprouts have been processed into various health foods. In the present study, four isoflavones were purified from the seeds and sprouts of chickpea by high-speed countercurrent chromatography (HSCCC) using two biphasic solvent systems composed of n-hexane-ethyl acetate-methanol-water (5:5:5:5, v/v) and ethyl acetate-water (1:1, v/v). The results indicated that 14.2 mg of formononetin, 15.7 mg of biochanin A, 9.1 mg of ononin, 11.3 mg of biochanin A-7-O-β-D-glucoside were obtained from 150 mg of sprout extracts with the purity of 92.26%, 95.86%, 95.32%, and 96.56%, respectively. Compared with the sprouts, separation of seed extracts yielded less amounts of biochanin A-7-O-β-D-glucoside and biochanin A with lower purity. The results indicate that four main isoflavones in chickpea, i.e., isoflavones, formononetin, biochanin A, ononin, and biochanin A-7-O-β-D-glucoside, are substantially increased by biosynthesis during the seed germination. [ABSTRACT FROM AUTHOR]

The toroidal coil using an equilateral triangular core has improved both retention of the stationary phase and peak resolution of the conventional toroidal coil in centrifugal countercurrent chromatography. To further improve the retention of stationary phase and peak resolution, a novel zigzag toroidal coil was designed and the performance of the system was evaluated at various flow rates. The results indicated that both retention of stationary phase and peak resolution were improved as the flow rate was decreased. Modification of the tubing by pressing at given intervals with a pair of pliers improved the peak resolution without increasing the column pressure. All these separations were performed under low column pressure indicating the separation can be further improved by increasing the column length and/or revolution speed without damaging the separation column. [ABSTRACT FROM AUTHOR]

Preparative separation of elatine in Delphinium shawurense was achieved for the first time using high speed countercurrent chromatography (HSCCC). The separation was performed with a solvent system composed of ethyl acetate-chloroform-methanol-water (3:0.1:2:3, v/v) using the lower organic phase as a mobile phase under a revolution speed of 800 rpm. This yielded 72 mg of elatine at over 97% purity with an approximately 95% recovery. The chemical structure was identified by MS and NMR. [ABSTRACT FROM AUTHOR]

Following an initial cleanup step on the AB-8 macroporous resin, high-speed countercurrent chromatography (HSCCC) was successfully applied for the first time to the isolation and purification of four flavonoids from Flos Gossypii. HSCCC was performed with a two-phase solvent system composed of chloroform-methanol-isopropanol-water (5:5:1:3, v/v) adding 0.4% phosphoric acid in the aqueous stationary phase. The separation yielded quercetin (5.6 mg), quercetin-3'-O-D-glucoside (7.2 mg), quercetin-3-O-β-D-glucoside (16 mg), quercetin-7-O-β-D-glucoside (8.3 mg), from 100 mg of the crude extract in a one step separation. The structure identification was made by 1H NMR, 13C NMR. [ABSTRACT FROM AUTHOR]