Haji Akber Aisa

Preparative isolation and purification of isobenzofuranone derivatives and saponins from seeds of Nigella glandulifera Freyn by high-speed counter-current chromatography combined with gel filtration

Although the medicinal plant and food Nigella glandulifera Freyn has been researched for decades, isobenzofuranones have never been isolated before. Two isobenzofuranone derivatives and two saponins were successfully separated and purified from seeds of N. glandulifera Freyn by high-speed counter-current chromatography (HSCCC) with the optimized two-phase solvent system, n-hexane-ethyl acetate-methanol-water (7:3:5:5, v/v). Salfredin B(11) (22.1mg, HPLC purity 95.3%), 5, 7-dihydroxy-6-(3-methybut-2-enyl) isobenzofuran-1(3H)-one (18.9mg, HPLC purity 97.3%) and crude sample 2 (555mg) were separated from 600mg of ethyl acetate extract of N. glandulifera Freyn. Following a cleaning-up step by chromatography on Sephadex LH-20, hederagenin (12mg) and 3-O-[beta-d-xylopyranosyl-(1-->3)-alpha-l-rhamnopyranosyl-(1-->2)-alpha-l-arabinopyranosyl]-hederagenin (45mg) were separated from sample 2. All of the fractions before peak II were collected and subjected to a Sephadex LH-20 column and eluted by methanol, two of triterpene saponins (12mg of hederagenin and 45mg of 3-O-[beta-d-xylopyranosyl-(1-->3)-alpha-l-rhamnopyranosyl-(1-->2)-alpha-l-arabinopyranosyl]-hederagenin) were isolated. The structures of peak fractions were identified by IR, electron ionization MS, (1)H NMR and (13)C NMR. 5, 7-Dihydroxy-6-(3-methybut-2-enyl) isobenzofuran-1(3H)-one was isolated for the first time from higher plant and salfredin B11 was isolated for the first time in this plant.

A LC/QTOF-MS/MS Application to Investigate Chemical Compositions in a Fraction with Protein Tyrosine Phosphatase 1B Inhibitory Activity from Rosa Rugosa Flowers

INTRODUCTIONnRosa rugosa flowers used as herbal medicine possess many activities. A fraction extracted by ethyl acetate exhibited strong inhibitive activity against protein tyrosine phosphatase 1B (PTP1B) in vitro.nnnOBJECTIVEnEstablish an efficient method of LC coupled to quadrupole time-of-flight (QTOF) with tandem MS/MS to investigate the compositions in the active fraction.nnnMETHODSnChemical compositions were separated and investigated by LC/QTOF-MS/MS in negative electrospray ionisation (ESI) mode at different collision energy (CE) values. The maximal structural information was obtained for the identification of components.nnnRESULTSnA total of 75 compounds including tannins, their related compounds and flavonoids were identified or partially characterised according to accurate mass and the characteristic fragments at low and high CE. Meanwhile, the fragmentation pathways of gallotannins and ellagitannins (hexahydroxydiphenoyl group and lactonised valoneoyl group) were studied and proposed and were used to trace tannins in crude extracts.nnnCONCLUSIONnThe results suggest that this fraction is a source of PTP1B inhibitory activity with a potential for treating diabetes.

Preparation of metallic pivot-based imprinted monolith for polar template

One of the main challenges in MIPs preparation is the proper MIP monolith design for water-soluble compounds due to the difficulty in satisfying the demands of both good column permeability and affinity to polar template. A new strategy of metallic pivot in a ternary porogenic system of dimethyl sulfoxide (DMSO)-dimethylformamide (DMF)-1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) was suggested to solve this problem. An imprinted monolithic column with high porosity and good permeability was synthesized using a mixture of methyl gallate (template), 4-vinylpyridine, ethylene glycol dimethacrylate, and cobalt acetate. Some polymerization factors, such as template-monomer molar ratio and the composition of the ionic liquid, on the imprinting effect of the resulting MIPs monoliths were systematically investigated. In a mobile phase of acetonitrile-buffer, the greatest imprinting factor of 10.9 was obtained on the MIPs monolith with the optimized polymerization parameters. Thermodynamic analysis for separation demonstrated that the separation between the template and its analogs on the ion-mediated MIPs monolith is an enthalpy-controlled process.

bioassay-guided isolation of antioxidants from astragalus altaicus by combination of chromatographic techniques

An efficient method for bioassay-guided preparative isolation of antioxidants from the n-butanol extract of Astragalus altaicus Bunge was ingeniously developed by combination of silica gel column chromatography and high-speed counter-current chromatography. Under the bioassay-guidance of antioxidant activities, the antioxidants were gradually separated from the crude sample of Astragalus altaicus Bunge by silica gel column chromatography and high-speed counter-current chromatography. Silica gel column chromatography separation was performed with chloroform, chloroform-methanol (100:1~5:1, v/v) and chloroform-methanol-water (5:1:0.1~2:1:0.1, v/v/v). High-speed counter-current chromatography separation was performed with a two-phase solvent system composed of ethyl acetate-n-butanol-water (2:1:6, v/v/v), which was successfully selected by thin layer chromatography analysis, at a flow rate of 1.5 mL/min. As a result, isorhamnetin-3-gentiobioside (20.8 mg), rutin (82.0 mg), and narcissin (12.8 mg) were obtained for the first time from 200 mg of the crude sample, ABS-5 of Astragalus altaicus Bunge. The purities were all at over 95% by high-performance liquid chromatography analysis, and their structures were unambiguously identified by mass spectroscopy, (1) H, and (13) C nuclear magnetic resonance spectroscopy. Antioxidant activities of the three compounds were also assayed by in vitro ABTS [2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) diamonium salt] radical cation scavenging activity. Among them, rutin possessed the highest antioxidant capacity with SC(50) value of 22.15 μg/mL.

Diterpenoid constituents of Euphorbia macrorrhiza.

Ten diterpenoids, named macrorilone A-B, macroripremyrsinone A, macrorilathyrone A-B, macrorieuphorone A-B and macroricasbalone A-C, together with ten known diterpenoids, jatrophalone, sikkimenoids A-D, jatrophodione A, latilagascenes F, jolkinol B, 15β-O-benzoyl-5α-hydroxyisolathyrol and jatrophalactone were isolated from the whole plant of Euphorbia macrorrhiza C.A. Mey. These diterpenoids belong to six skeleton-types, including jatropholane, premyrsinane, lathyrane, euphoractin, casbene and rhamnofolane diterpenoids. Their structures were elucidated by extensive analysis of 1D, 2D NMR and HRESIMS spectroscopic data. The absolute configurations of macrorilone B, macroripremyrsinone A and macrorilathyrone A were established by comparing their experimental and calculated electronic circular dichroism (ECD) spectra. Several of the isolated compounds exhibited weak cytotoxicity against the KB and KBv200 cell lines with IC50 values ranging from 21.19 to 47.87μM. Some also showed multidrug resistance (MDR) reversal activity, among which macrorilathyrone B exhibited a remarkable inhibitory effect on P-gp-mediated drug exclusion.

A sample pretreatment strategy for pH-zone-refining counter-current chromatography.

A sample pretreatment method using acid-base extraction was established for pH-zone-refining counter-current chromatography (CCC) to increase the yield of the target compound. As the most important step, selection of two-phase solvent system for pH-zone-refining CCC should follow some rules. One of these rules is that when pH of two-phase solvent system is around 2 (for an acidic analyte) or 10 (for a basic analyte), partition coefficient values of K(acid) or K(base) should be much greater than 1. According to this rule, a new pretreatment method was developed that could substantially increase the yield of the target compound in pH-zone-refining CCC. The separation of the crude alkaloids extracted from the seeds of Sophora alopecuroides was selected as an example to show the advantage of this method. Before CCC separation, 20 g of crude sample was extracted 3 times with the selected two-phase solvent system composed of MtBE-CH₃CN-H₂O (2:2:3, v/v), where pH of the upper phase was adjusted with triethylamine to 10. A 10 g amount of the second basic extract thus obtained was subjected to pH-zone-refining CCC separation. As a result, 169 mg of sophoramin and 696 mg of sophoearpin were isolated from the second basic extract, where the yields have been doubled compared with those of the untreated sample (crude sample). Experimental results showed that the present method for pretreating the crude sample could produce substantially higher yields of target compounds in pH-zone-refining CCC.

Hepatoprotective activities of a sesquiterpene-rich fraction from the aerial part of Cichorium glandulosum

BackgroundCichorium glandulosum Boiss. et Huet is used for treatment of liver disorders, and its effects are attributed to sesquiterpenes. This study aims to investigate the hepatoprotective effects of a sesquiterpene-rich fraction (SRF) from the aerial part of C. glandulosum on carbon tetrachloride (CCl4)-induced acute hepatotoxicity in mice, and on priming with Bacillus Calmette–Guerin (BCG) followed by lipopolysaccharide (LPS)-induced immunological liver injury in mice.MethodsSRF was suspended in water and administered to mice at 0.05, 0.10 and 0.20 g/kg body weight for 7 consecutive days. An active control drug (bifendate pills) was suspended in distilled water and administered to mice at 0.40 g/kg body weight for 7 consecutive days. Hepatotoxicity was induced by intraperitoneal injection of 0.1% CCl4 (0.2 mL/mouse) at 13 h before the last drug administration, or by tail intravenous injection of BCG (0.2 mL/mouse) before the first drug administration and LPS (0.2 mL/mouse; 8 μg) at 15 h before the last drug administration. Blood samples and the livers were collected for evaluation of the biochemical parameters of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total bilirubin (TBIL).ResultsSRF significantly reduced the impact of CCl4 toxicity. The highest dose of SRF (0.20 g/kg) was the most effective, reflected by significant reductions in the levels of AST (P = 0.001), ALT (P = 0.000) and TBIL (P = 0.009). The serum enzymatic levels induced by BCG and subsequent LPS injection were significantly and dose-dependently restored by SRF, reflected by significant reductions in the levels of AST (P = 0.003), ALT (P = 0.003) and TBIL (P = 0.007) for the highest dose of SRF (0.20 g/kg).ConclusionSRF is hepatoprotective in animal models of chemical and immunological acute liver injury.

Novel Design for Centrifugal Counter-Current Chromatography: VI. Ellipsoid Column

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.

2-ISOPROPYL-6-METHYLPYRIMIDIN-4(3H)-ONE AND TARAXASTEROL FROM THE STEMS OF Cichorium glandulosum

0009-3130/11/4704-0664 2011 Springer Science+Business Media, Inc. 1) Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences, Urumqi, 830011, P. R. China, e-mail:haji@xjb.ac.cn; 2) College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, 455002, P. R. China, e-mail:hkwu@aynu.edu.cn. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 581–582, July–August, 2011. Original article submitted January 20, 2010. Chemistry of Natural Compounds, Vol. 47, No. 4, September, 2011 [Russian original No. 4, July–August, 2011]