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Zhao H, Dai B, Xu L, Wang X, Qiao X, Xu Z. Preparation and application of immobilised ionic liquid in solid-phase extraction for determination of trace acrylamide in food samples coupled with high-performance liquid chromatography. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2014; 94:1787-1793. [PMID: 24282135 DOI: 10.1002/jsfa.6493] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 09/29/2013] [Accepted: 11/26/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND Acrylamide has attracted worldwide concerns because of its demonstrated neurotoxicity, genetoxicity and reproductive-development toxicity. It is necessary to control acrylamide production during food processing and protect human health. RESULTS In this study, a functionalised material was synthesised by immobilising an ionic liquid onto an activated silica gel surface. The adsorption ability of the material towards acrylamide was evaluated, and the results showed that it had high adsorption capacity. Scatchard analysis indicated that the binding sites in the prepared material had two distinct groups (high and low affinity binding sites). The saturated adsorption capacity (Q(max,1)) was 7.9 mg g(-1) due to the high affinity binding sites, and another saturated adsorption capacity (Q(max,2)) was 2.3 mg g(-1) due to the low affinity binding sites. This prepared material also offered fast kinetics for adsorption of the acrylamide. Using this material as sorbent, a method of solid-phase extraction coupled with high-performance liquid chromatography (SPE-HPLC) for analysis of acrylamide in foods was developed. Under optimal conditions, the limit of detection (S/N = 3) of this method for acrylamide was 2.1 µg kg(-1), and the RSD for five replicate extractions of 50 μL(-1) acrylamide was 4.5%. The blank potato and bread crumb samples spiked with acrylamide at different levels of 10.0 and 15.0 µg kg(-1) were extracted and determined respectively by this developed method, and recoveries ranging from 83.0% to 89.1% were obtained. Finally, this method was applied to quantitative detection of acrylamide in bread crust and cracker samples. CONCLUSION With high sensitivity and pre-treatment simplicity, this SPE-HPLC method could provide a new tool for the rapid determination of acrylamide in the food samples.
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Wang H, Mei WL, Guo ZK, Xia ZF, Zhong HM, Dai HF. [Chemical constituents of Dalbergia odorifera]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2014; 39:1625-1629. [PMID: 25095373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Fourteen compounds were isolated from Dalbergia odoriferae and purified by repeated column chromatography on silica and sephadex LH-20 gel and structurally identified by spectral analysis. These compounds were identified as 4, 9-dimethoxy-3-hydroxypterocarpan (1), medicarpin (2), 2', 4', 5-trihydroxy-7-methoxyisoflavone (3), 2', 3', 7-trihydroxy-4'-methoxyisoflavan (4), formononetin (5), 3, 8-dihydroxy-9-methoxypterocarpan (6), koparin (7), 3-hydroxy-9-methoxypterocarp-6a-ene (8), 2'-hydroxyformononetin (9), stevenin (10), 2', 7-dihydroxy-4', 5'-dimethoxyisoflavone (11), lyoniresinol (12), 2, 4-dihydroxy-5-methoxy-benzophenone (13) and neokhriol A (14). Compounds 1, 3, 4, 6, 8, 12 and 14 were isolated from this plant for the first time. Antibacterial activity assay showed that compound 4 had inhibitory effect on Ralstonia solanacearum.
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Braga FR, Carvalho RO, Silva AR, Araújo JV, Frassy LN, Lafisca A, Soares FEF. Predatory capability of the nematophagous fungus Arthrobotrys robusta preserved in silica gel on infecting larvae of Haemonchus contortus. Trop Anim Health Prod 2014; 46:571-4. [PMID: 24510197 DOI: 10.1007/s11250-014-0544-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2014] [Indexed: 11/25/2022]
Abstract
Biological control of gastrointestinal nematodiasis in ruminants is an alternative to reduce the number of infective larvae. The fungal isolates predatory activity preservation is a basic requirement for the success of this control type. The aim of this work is to evaluate the predatory capacity of the fungus Arthrobotrys robusta (isolate I-31), preserved on silica gel on infective larvae of Haemonchus contortus under laboratory conditions on 2 % water agar (2 % WA). In this essay, A. robusta storage on silica gel showed successful predatory activity on H. contortus L3 larvae (p < 0.01) compared to the control group. Nematophagous fungi were not observed in the control group during the experiment. There was a significant reduction (p < 0.01) of 73.84 % in the means of H. contortus (L3) recovered from treatment with isolate I-31 compared to the control without fungi. Results indicate that A. robusta (I-31) could survive stored on silica gel for at least 7 years and keep its predatory activity on H. contortus (L3).
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Hu SW, Chen S. Adsorption of triazine derivatives with humic fraction-immobilized silica gel in hexane: a mechanistic consideration. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:8524-8532. [PMID: 23931716 DOI: 10.1021/jf4019118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A fraction of humic acid is collected under acidic conditions, then immobilized on silica gel and used as the adsorbent for various symmetrical triazine (s-triazine) derivatives in hexane. The enhanced hydrogen bonding between the analyte and humic fraction molecules, not the complexation interaction, is responsible for the adsorption observed in hexane, based on Fourier transform infrared (FTIR) spectroscopy results. The percentage of adsorption in hexane for all s-triazine derivatives reaches nearly 100% in 1 h, independent of the type, position, and size of the substituent on the aromatic nitrogen heterocyclic ring. Other factors leading to the variation of the percentage of adsorption include the type of liquid phase and the additive of acidic or basic origin present in the matrix.
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Datta S, Zhou YD, Nagle DG. Comparative study of chromatographic medium-associated mass and potential antitumor activity loss with bioactive extracts. JOURNAL OF NATURAL PRODUCTS 2013; 76:642-7. [PMID: 23441686 PMCID: PMC3683388 DOI: 10.1021/np300858c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Natural product drug discovery programs often rely on the use of silica (Si) gel, reversed-phase media, or size-exclusion resins (e.g., RP-C18, Sephadex LH-20) for compound purification. The synthetic polymer-based sorbent Diaion HP20SS (cross-linked polystyrene matrix) is used as an alternative to prepare purified natural product libraries. To evaluate the impact of chromatographic media on the isolation of biologically active, yet chromatographically unstable natural products, Diaion HP20SS was evaluated side-by-side with normal-phase sorbents for irreversible binding of extract constituents and their effects on bioactivity. An array of chemically diverse natural product-rich extracts was selected as a test panel, and a cell-based reporter assay for hypoxia-inducible factor-1 (HIF-1) was employed to monitor potential change(s) in bioactivity. Silica gel caused significant irreversible binding of three out of 10 extracts. Curcuma longa, Saururus cernuus, and Citrus reticulata extracts showed decreased HIF-1 inhibitory activity after elution through Si gel. An additional nonpolar column wash of HP20SS with EtOAc retained considerable bioactivities of active extracts. In general, Si gel produced the greatest loss of bioactivity. However, HP20SS elution reduced significantly HIF-1 inhibitory activity of certain extracts (e.g., Asimina triloba).
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81
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Agarwal M, Tardio J, Mohan SV. Biohydrogen production from kitchen based vegetable waste: effect of pyrolysis temperature and time on catalysed and non-catalysed operation. BIORESOURCE TECHNOLOGY 2013; 130:502-509. [PMID: 23313698 DOI: 10.1016/j.biortech.2012.11.094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Revised: 11/19/2012] [Accepted: 11/20/2012] [Indexed: 06/01/2023]
Abstract
Pyrolysis of kitchen based vegetable waste (KVW) was studied in a designed packed bed reactor. The effect of process parameters like temperature, time and catalyst on bio-gas yield and its composition was studied. The total bio-gas yield was found to be maximum with non-catalysed operation (260ml/g) at 1073K (180min). Higher hydrogen (H(2)) yield with non-catalysed operation (32.68%) was observed at 1073K (180min) while with catalysed operation the requisite temperature (873K) and time (120min) reduced with both silica gel (33.34%) and sand (41.82%) thus, saving energy input. Methane (CH(4)) yield was found to be highest (4.44times than non-catalysed and 1.42 with silica gel) in presence of sand (71.485ml/g) at medium temperature (873K) and time (60min). The catalyst operation reduced the carbondioxide (CO(2)) share from 47.29% to 41.30% (silica gel catalysed) and 21.91% (sand catalysed) at 873K.
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82
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Chen Y, Wang GK, Wu C, Qin MJ. [Chemical constituents of Gentiana rhodantha]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2013; 38:362-5. [PMID: 23668010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
OBJECTIVE To determine the chemical constituents of Gentiana rhodantha. METHOD To isolate the constituents, column chromatography over silica gel, MCI, Sephadex LH-20 and C18 reverse-phased silica gel were used. Spectroscopic methods were used to elucidate the structures of the isolated compounds. RESULT Sixteen compounds were isolated and elucidated as ten phonemic compounds, namely 1,3,7,8-tetrahydroxylxanthone (1), rhodanthenone D (2), 1,3,6,7-tetrahydroxylxanthone (3), 1,3,7-trihydroxy-4,8-dimethoxyxanthone (4), quercetin (5), isoorientin (6), mangiferin (7), norswertianolin (8), gallic acid ethyl ester (9) and salicylic acid (10), and six triterpenes including alpha-amyrin (11), erythrodiol 3-O-palmitate (12), ursolic aldehyde (13), uvaol 3-O-acetyl (14), ursolic acid (15) and 2alpha-hydroxyursolic acid (16). CONCLUSION Compounds 4-6, 8, 10-12, 15 and 16 were isolated from this plant for the first time. Compounds 1 and 3 were obtained firstly from the genus Gentiana and compounds 9, 13-14 were firstly from the family Gentianaceae.
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Zhang Z, Zou H, Ou J. Polysaccharide-derived chiral stationary phases in capillary electrochromatography enantioseparations. Methods Mol Biol 2013; 970:457-467. [PMID: 23283796 DOI: 10.1007/978-1-62703-263-6_29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Capillary electrochromatography (CEC) has been shown to be a promising technique for miniaturized enantioseparations. Here we present the preparation and application of positively charged cellulose derivative-based chiral stationary phases (CSPs) for the CEC separation of enantiomers. The cellulose derivatives were chemically immobilized onto diethylenetriaminopropylated silica gel using tolylene-2,4-diisocyanate as a spacer. The separation of enantiomers in CEC can be performed on the positively charged CSPs with nonaqueous and aqueous mobile phases.
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84
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Scriba GKE, Jáč P. Enantioseparations by capillary electrophoresis using cyclodextrins as chiral selectors. Methods Mol Biol 2013; 970:271-287. [PMID: 23283784 DOI: 10.1007/978-1-62703-263-6_17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Due to their commercial availability, cyclodextrins are the most frequently used chiral selectors in capillary electrophoresis as documented by the numerous publications in the field. A variety of migration modes can be realized depending on the characteristics of the cyclodextrins and the analytes. The basic considerations regarding the development of a chiral CE method employing cyclodextrins as chiral selectors are briefly discussed. The presented examples illustrate the separation modes of an acidic and a basic analyte with native and charged cyclodextrin derivatives as a function of the pH of the background electrolyte and the cyclodextrin concentration.
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85
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Verma PK, Kamboj VK. HPTLC method for estimation of olmesartan medoxomil in tablet formulation with stability studies. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 2013; 26:209-215. [PMID: 23261750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A rapid resolution high performance thin layer chromatography (HPTLC) method has been developed and validated for estimation of olmesartan medoxomil in tablet formulations. This paper describes accurate, precise, specific and reproducible method and its degradation products, related impurities for assessment of purity of bulk drug and stability of its tablet formulations. The method involve silica gel 60 F254 high performance thin layer chromatography and densitometric detection at 264 nm using toluene - acetonitrile- methanol - ethyl acetate - acetic acid (5:3.5:0.3:1:0.3 v/v/v/v). Calibration curve ranges between 300-800 ng/spot-1 olmesartan medoxomil. Experimental design was involved forced degradation of drug, optimization of mobile phase, detection made and other chromatographic phase and study of linearity range. The total time for chromatographic separation was 6 min with a total analysis time 15 min. The proposed method was validated for its linearity, precision, recovery studies and robustness.
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86
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Tao XY, Zhang DW, Chen RD, Yin YZ, Zou JH, Xie D, Yang L, Wang CM, Dai JG. [Chemical constituents from cell cultures of Morus alba]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2012; 37:3738-3742. [PMID: 23627170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The column chromatography on silica gel, Sephadex LH-20 and semi-preparative HPLC were used to separate and purify the compounds from the EtOAc extract of medium and MeOH extract of cell cultures of Morus alba. Eight compounds were isolated. Based on physico-chemical properties and spectroscopic data, their structures were identified as isobavachalcone (1), genistein (2), norartocarpetin (3), albanin A (4), guangsangon E (5), mulberrofuran F (6), chalcomoracin (7), kuwanon J (8). Compounds 3-6 were isolated from the cell cultures of M. alba for the first time.
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87
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Dakova I, Yordanova T, Karadjova I. Non-chromatographic mercury speciation and determination in wine by new core-shell ion-imprinted sorbents. JOURNAL OF HAZARDOUS MATERIALS 2012; 231-232:49-56. [PMID: 22771349 DOI: 10.1016/j.jhazmat.2012.06.034] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 06/15/2012] [Accepted: 06/17/2012] [Indexed: 06/01/2023]
Abstract
In this study new Hg(II) core-shell imprinted sorbents (Hg(II)-IIPs) were prepared and tested for speciation and determination of Hg in wine. The silica gel, chemically modified with 3-(trimethoxysilyl)propyl methacrylate (TSPM) was used as supporting material. The Hg(II)-imprinted polymer layer was grafted by copolymerization of methacrylic acid and trimethylolpropane trimethacrylate in the presence of Hg(II) complexes with two different chelating agents: 1-pyrrolidinedithiocarboxylic acid (P(PDC-Hg)/SiG) and 1-(2-thiazolylazo)-2-naphthol (P(TAN-Hg)/SiG). High selectivity and fast kinetics of processes of sorption and desorption for Hg(II) were found by using P(PDC-Hg)/SiG. Recovery experiments performed for selective determination of inorganic mercury in wines showed that the interfering organic matrix did not influence the extraction efficiency. Column solid phase extraction scheme was developed for the determination and speciation of Hg in wines. The limit of detection (LOD) achieved for inorganic mercury determination in wine samples is 0.02 μg L(-1) (3σ), measured by CV AAS. The relative standard deviation varied in the range 6-11% at 0.05-2 μg L(-1) Hg levels. The sorbents showed high mechanical and chemical stability and extraction efficiency has not changed after more than 50 sorption/desorption cycles.
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Dickson DJ, Luterra MD, Ely RL. Transcriptomic responses of Synechocystis sp. PCC 6803 encapsulated in silica gel. Appl Microbiol Biotechnol 2012; 96:183-96. [PMID: 22846903 DOI: 10.1007/s00253-012-4307-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 07/12/2012] [Accepted: 07/13/2012] [Indexed: 11/26/2022]
Abstract
Global gene expression of Synechocystis sp. PCC 6803 encapsulated in silica gel was examined by microarray analysis. Cultures were encapsulated in gels derived from aqueous precursors or from alkoxide precursors and incubated under constant light for 24 h prior to RNA extraction. Cultures suspended in liquid media were exposed to 500 mM salt stress and incubated under identical conditions for comparison purposes. The expression of 414 genes was significantly altered by encapsulation in aqueous-derived gels (fold change ≥1.5 and P value < 0.01), the expression of 1,143 genes was significantly altered by encapsulation in alkoxide-derived gels, and only 243 genes were common to both encapsulation chemistries. Additional qRT-PCR analyses of four selected genes, ggpS, cpcG2, slr5055, and sll5057, confirmed microarray results for those genes. These results illustrate that encapsulation stress is quite different than salt stress in terms of gene expression response. Furthermore, a number of hypothetical and unknown proteins associated with encapsulation and alcohol stress have been identified with implications for improving encapsulation protocols and rationally engineering microorganisms for direct biofuel production.
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89
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Savchuk II, Zaĭchenko AM, Tsyganenko ES. [Biological activity of Penicillium sp. 10-51 exometabolites]. MIKROBIOLOHICHNYI ZHURNAL (KIEV, UKRAINE : 1993) 2012; 74:52-56. [PMID: 23088100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Silica gel column chromatography (silica gel "L" II kind of activity 100/160 mkm) of the chloroform extract from the cultural filtrate of Penicillium sp. 10-51 gave two fractions (chloroform and chloroform-acetone, 5:1) having biological activity. Recrystallization yielded two compounds. On the basis of physico-chemical and spectral data these compounds were identified as curvularin and hydroxycurvularin, which have a large spectrum of biological action as to bacteria, yeast, blue-green algae and phytopathogenic micromycetes.
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90
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Chen W, Tang S, Qin N, Zhai H, Duan H. [Antioxidant constituents from Smilax riparia]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2012; 37:806-810. [PMID: 22715727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
By repeated column chromatography, including silica gel, toyopearl HW-40 and preparative HPLC, thirteen compounds (1-13) were isolated and purified from Smilax riparia. On the basis of spectral data analysis, the structures of isolated compounds were elucidated as 5-methoxy-[6]-gingerol (1), dehydroabietic acid (2), pteryxin (3), 2-methylphenyl-1-O-beta-D-glucopyranoside (4), 3,5-dimethoxy-4-hydroxybenzonic acid (5), isovanillin (6), vanillic acid (7), p-hydroxycinnamic acid (8), p-hydroxycinnamic methyl ester (9), p-hydroxybenzaldehyde (10), ferulic acid methyl ester (11), benzoic acid (12) and 5-hydroxy-methyl-2-furalclehyde (13). Compounds 1-4 and 8-12 were isolated from this genus for the first time. All compounds were isolated from this plant for the first time. Compounds 1 and 5-11 showed antioxidant activities on DPPH method.
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He L, Yang S, Wu D, Cui T, Wei D, Ding Z. [Coumarins from Skimmia arborescens and its anti-inflammatory effect]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2012; 37:811-813. [PMID: 22715728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
To investigate chemical constituents contained in Skimmia arborescens. The chemical constituents were separated by silica gel column chromatography, pharmadex LH-20, RP-C18, and 1H, 13C-NMR spectroscopic analysis were employed for the structural elucidation. Six coumarin compounds were separated from S. arborescens. Their structures were elucidated as umbelliferone (1), scopoletin (2), scopolin (3), nodakenetin (4), skimmin (5), 6, 7-dimethoxycoumarin (6), and all compounds were separated from the plant for the first time. Using the model of ear swelling caused by xylol of mice, the anti-inflammatory effect of its total extract was evaluated. The result indicated that middle and high dose groups of its total extract could obviously inhibit the ear swelling caused by xylol of mice.
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Zhang K, Wang X, Huang J, Liu Y. Purification of L-alpha glycerylphosphorylcholine by column chromatography. J Chromatogr A 2012; 1220:108-14. [PMID: 22197252 DOI: 10.1016/j.chroma.2011.12.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 11/16/2011] [Accepted: 12/01/2011] [Indexed: 11/28/2022]
Abstract
Colorless L-alpha glycerylphosphorylcholine (L-α-GPC) was obtained at 99.8% purity, 69.8% recovery, and with a specific rotation of -2.5° via a five-step procedure. L-α-GPC was first produced by phospholipase A(1) hydrolysis of soy lecithin powder. Ca(2+) and Cl(-) were then effectively removed using two successive 001×7 cation and D311 anion exchange resin column chromatography procedures. Silica gel column chromatography and decoloration with active carbon were then applied to remove remaining impurities and colorant. Characterization of the L-α-GPC product was well in agreement with the standard. The resin and silica gel showed remarkable ability for L-α-GPC isolation after 10 uses. Thus, this study presents a simple and cost-effective method for preparing L-α-GPC with high yield and purity, low cost, and environmental friendliness, and encourages future investigation into its adaptation for industrial applications.
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Velho-Pereira RM, Barhate CR, Kulkarni SR, Jagtap AG. Validated high-performance thin-layer chromatographic method for the quantification of thymoquinone in Nigella Sativa extracts and formulations. PHYTOCHEMICAL ANALYSIS : PCA 2011; 22:367-73. [PMID: 21337651 DOI: 10.1002/pca.1289] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 06/07/2010] [Accepted: 09/23/2010] [Indexed: 05/24/2023]
Abstract
INTRODUCTION The surge of interest in naturally occurring phytochemicals with anticancer potential has led to the discovery of many molecules, one of them being thymoquinone (TQ) the bioactive constituent of the volatile oil of black seed, Nigella sativa L. (NS). OBJECTIVE The aim of the present work was to develop and validate an HPTLC method for determination of TQ in NS extracts, commercially available marketed oils, polyherbal formulations and in lipid-based oral and parenteral formulations prepared in-house. METHODOLOGY Analysis of TQ was performed on TLC aluminium plates pre-coated with silica gel 60F-254. Linear ascending development was carried out in twin trough glass chamber, saturated with mobile phase consisting of toluene-cyclohexane (8 : 2, v/v) at ambient temperature. Camag TLC scanner III was used for the spectrodensitometric scanning and analysis in absorbance mode at 254 nm. RESULTS The method was found to give compact spots for TQ (R(f) value of 0.28 ± 0.05) and was linear over the range 100-1400 ng/spot (r(2) = 0.9921 ± 0.0020). Accuracy, precision and repeatability were all within the required limits. The mean recoveries measured at three concentrations were higher than 95% with RSD ≤ 3%. CONCLUSION The HPTLC method developed was found to be relatively simple, rapid and accurate for the routine analysis of TQ in extracts, marketed oils, polyherbal and in-house formulations.
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Canullo L, Dellavia C, Heinemann F. Maxillary sinus floor augmentation using a nano-crystalline hydroxyapatite silica gel: case series and 3-month preliminary histological results. Ann Anat 2011; 194:174-8. [PMID: 21640571 DOI: 10.1016/j.aanat.2011.04.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Accepted: 10/01/2010] [Indexed: 11/18/2022]
Abstract
The aim of this case series is to histologically examine a new hydroxyapatite in sinus lift procedure after 3 months. Ten 2-stage sinus lifts were performed in 10 healthy patients having initial bone height of 1-2mm and bone width of 5mm, asking for a fixed implant-supported rehabilitation. After graft material augmentation, a rough-surfaced mini-implant was inserted to maintain stability of the sinus widow. A bioptical core containing a mini-implant was retrieved 3 months after maxillary sinus augmentation with NanoBone(®) and processed for undecalcified histology. From the histomorphometric analysis, NanoBone(®) residuals accounted for the 38.26% ± 8.07% of the bioptical volume, marrow spaces for the 29.23% ± 5.18% and bone for the 32.51% ± 4.96% (new bone: 20.64% ± 2.96%, native bone: 11.87% ± 3.27%). Well-mineralized regenerated bone with lamellar parallel-fibred structure and Haversian systems surrounded the residual NanoBone(®) particles. The measured bone-to-implant contact amounted to 26.02% ± 5.46%. No connective tissue was observed at the implant boundary surface. In conclusion, the tested material showed good histological outcomes also 3 months after surgery. In such critical conditions, the use of a rough-surfaced mini-implant showed BIC values supposed to be effective also in case of functional loading. Although longer follow-up and a wider patient size are needed, these preliminary results encourage further research on this biomaterial for implant load also under early stage and critical conditions.
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Smital T, Terzic S, Zaja R, Senta I, Pivcevic B, Popovic M, Mikac I, Tollefsen KE, Thomas KV, Ahel M. Assessment of toxicological profiles of the municipal wastewater effluents using chemical analyses and bioassays. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2011; 74:844-851. [PMID: 21159381 DOI: 10.1016/j.ecoenv.2010.11.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2010] [Revised: 11/09/2010] [Accepted: 11/25/2010] [Indexed: 05/30/2023]
Abstract
The hazardous chemical contamination of untreated wastewater and secondary effluent from the wastewater treatment plant (WWTP) of the city of Zagreb, Croatia was comprehensively characterized using large-volume solid-phase extraction (SPE) and silica gel fractionation, followed by a detailed analysis of the resulting extracts by a combination of chemical and bioassay methods. Over 100 individual contaminants or closely related-contaminant groups were identified by high-resolution gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF). Ecotoxicity profiling of the investigated samples, including cytotoxicity, chronic toxicity and EROD activity; inhibition of the multixenobiotic resistance (MXR), genotoxicity and estrogenic potential, revealed the most significant contribution of toxic compounds to be present in polar fractions. Wastewater treatment using conventional activated sludge process reduced the initial toxicity of raw wastewater to various extents, ranging from 28% for algal toxicity to 73.2% for an estrogenic activity. The most efficient toxicity removal was observed for the polar compounds.
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96
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Feng W, Ou YF, Su Y, Li J, Ji T. [Chemical constituents of Ammopiptanthus mongolicus]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2011; 36:1040-1042. [PMID: 21809581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
OBJECTIVE To study the chemical constituents of aerial parts of Ammopiptanthus mongolicus. METHOD Isolation and purification were carried out on silica gel, Sephadex LH-20 and HPLC column chromatography. The structures of the compounds were identified by physico-chemical properties and spectral analysis. RESULT Nine compounds were isolated and identified as (+)-maackiain (1), brevifolin (2), 7-hydroxy-4'-methoxy isoflavanone (3), daidzein 4',7-diglucoside (4), genistein 4', 7-di-O-beta-D-glucoside (5), isolupalbigenin (6), ononin (7), beta-sitosterol (8), beta-daucosterol (9). CONCLUSION Compounds 2, 4 - 6 were obtained from the genus Ammopiptanthus for the first time.
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97
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Shepherd LD, McLay TGB. Two micro-scale protocols for the isolation of DNA from polysaccharide-rich plant tissue. JOURNAL OF PLANT RESEARCH 2011; 124:311-4. [PMID: 20927638 DOI: 10.1007/s10265-010-0379-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Accepted: 09/06/2010] [Indexed: 05/08/2023]
Abstract
The high polysaccharide content of some plant species hinders the successful isolation of their DNA. As an alternative to the macro-extraction methods previously published for polysaccharide-rich plants, we present two techniques (STE/CTAB and HEPES/CTAB), which are performed in microcentrifuge tubes. These protocols are suitable for small amounts of silica gel-preserved plant tissue such as are commonly available from endangered plants. The critical step to remove polysaccharides was performing initial washes in either STE (0.25 M sucrose, 0.03 M Tris, 0.05 M EDTA) or HEPES (2% β-mercaptoethanol, 0.2% PVP, 0.1 M HEPES, pH 8.0) buffer. Precipitating the DNA at room temperature with isopropanol also aided in decreasing polysaccharide co-precipitation. Of the two protocols we present the STE/CTAB method has the advantages of being more cost-effective and avoiding the use of the hazardous chemical β-mercaptoethanol.
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Ramaswamy BR, Shanmugam G, Velu G, Rengarajan B, Larsson DGJ. GC-MS analysis and ecotoxicological risk assessment of triclosan, carbamazepine and parabens in Indian rivers. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:1586-93. [PMID: 21216531 DOI: 10.1016/j.jhazmat.2010.12.037] [Citation(s) in RCA: 210] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 12/02/2010] [Accepted: 12/09/2010] [Indexed: 05/02/2023]
Abstract
Pharmaceutical and personal care products are used extensively worldwide and their residues are frequently reported in aquatic environments. In this study, antiepileptic, antimicrobial and preservative compounds were analyzed in surface water and sediment from the Kaveri, Vellar and Tamiraparani rivers, and in the Pichavaram mangrove in India by gas chromatography-mass spectrometry (GC-MS). The mean concentration of carbamazepine recorded in the Kaveri River water (28.3 ng/L) was higher than in the other rivers and the mangrove. Because carbamazepine is used only in human drugs, this may reflect the relative contributions of human excretions/sewage in these rivers. The mean triclosan level in the Tamiraparani River (944 ng/L) was an order of magnitude greater than in the other water systems, and the concentrations at two of the sites reported here (3800-5160 ng/L) are, to our best knowledge, among the highest detected in surface waters. Sediment levels were, however, comparable with other sites. We conclude that industrial releases are likely major contributors of triclosan into this river system. Among parabens, ethyl paraben was predominantly observed. Hazard Quotients suggest greater environmental risks for triclosan than for carbamazepine and parabens. This is the first study on antiepileptic, antimicrobial and preservatives in rivers and mangroves from India.
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Chiewpattanakul P, Phonnok S, Durand A, Marie E, Thanomsub BW. Bioproduction and anticancer activity of biosurfactant produced by the dematiaceous fungus Exophiala dermatitidis SK80. J Microbiol Biotechnol 2010; 20:1664-1671. [PMID: 21193821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A new biosurfactant producer was isolated from palm-oilcontaminated soil and later identified through morphology and DNA sequencing as the yeast-like fungus Exophiala dermatitidis. Biosurfactant production was catalyzed by vegetable oil, supplemented with a basal medium. The culture conditions that provided the biosurfactant with the highest surface activity were found to be 5% palm oil with 0.08% NH4NO3, at a pH of 5.3, with shaking at 200 rpm, and a temperature of 30 degrees C for a 14-day period of incubation. The biosurfactant was purified, in accordance with surfactant properties, by solvent fractionation using silica gel column chromatography. The chemical structure of the strongest surface-active compound was elucidated through the use of NMR and mass spectroscopy, and noted to be monoolein, which then went on to demonstrate antiproliferative activity against cervical cancer (HeLa) and leukemia (U937) cell lines in a dose-dependent manner. Interestingly, no cytotoxicity was observed with normal cells even when high concentrations were used. Cell and DNA morphological changes, in both cancer cell lines, were observed to be cell shrinkage, membrane blebbling, and DNA fragmentation.
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100
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Tan D, Chen Y, Ji L, Chou G, Wang Z. [Alkaloids from Senecio scandens]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2010; 35:2572-2575. [PMID: 21174767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
OBJECTIVE To investigate the alkaloids from Senecio scandens. METHOD Compounds were isolated with silica gel and Sephadex LH-20 column chromatography and their structures were determined by spectral analysis and chemical evidence. The hepatic cytotoxicity of isolated compounds was tested by MTT method in vitro. RESULT Six alkaloids were obtained and identified as adonifoline (1), 7-angeloylturneforcidine (2), hordenine (3), 1, 3, 6, 6-tetramethyl-5, 6, 7, 8-tetrahydro-isoquinolin-8-one (4), 4-(pyrrolidin-2-one) -phenyl acetic acid (5), (4-pyrrolidinophenyl) acetic acid (6). CONCLUSION Compound 6 is a new natural product, compounds 3, 4 were obtained from the genus Senecio for the first time, compounds 2, 5 were obtained from this plant for the first time. Compound 1 showed significant growth inhibitory effect against hepatocyte at 100 micromol x L(-1).
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