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30 August 2008, Volume 28 Issue 04 Previous Issue    Next Issue

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Study on Structure of Tannin in Prunus salicina Lindl. Fruits and Its Antioxidant Activity ZHANG Liang-liang;LI Min;LIN Peng;LIN Yi-ming; 2008, 28 (04):  1-6.  Abstract ( 718 )   PDF (993KB) ( 714 )   Save Contents of total phenolics and extractable condensed tannins in Prunus salicina Lindl. fruits were determined. Type of condensed tannins, degree of polymerization and distribution of polymer were characterized by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance (NMR) spectroscopy. The effects of tannins from P. salicina fruits on scavenging free radicals were determined by using 1,1-diphenyl-2-picryhydrazyl (DPPH·) free radical test. The results were showed as follows: total phenolics and extractable condensed tannins were 8.29%±1.30% and 1.43%±0.93%, respectively; Epicatechin was the basic units occurring in condensed tannins, A-type and B-type lin-kages were most common among the structural units of polymers. The average degree of polymerization was 5.3, and mean molecular weight was 1583.7u. EC50 value was 57.98mg/L by DPPH· scavenging test. Related Articles | Metrics

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Preparation of Novolak-type Phenolic Resin from Phenolated Wood LI Gai-yun;REN Hai-qing;QIN Te-fu;JIANG Ze-hui 2008, 28 (04):  7-12.  Abstract ( 690 )   PDF (990KB) ( 676 )   Save A novolak-type phenolic resin from phenolated wood and formaldehyde (PWF) was prepared under acidic condition. The effects of various reaction factors on product yield and softening point, including molar ratio, pH value, reaction temperature and reaction time, have been investigated by orthogonal test. The structures of PWF and traditional novolak-type phenolic resin (PF) were characterized by GPC, FT-IR and NMR. The results showed that the yield of PWF was notably affected by pH value and reaction temperature, and the softening point was significantly affected by charge ratio of formaldehyde to phenol. At molar ratio of n(phenol in phenolated wood):n(formaldehyde )1:0.75, reacted, 105℃ for 150min under the actual pH value of phenolated wood, the product yield of 124% and the softening point of 110℃ for PWF were attained. The structure of PWF was similar with that of PF. The phenolic nuclei were linked by a methylene linkage at its ortho-para and para-para positions to a phenolic hydroxyl group. On the other hand, PWF contained fragments of liquefied wood, while the relative molecular mass (Mr) was lower and its distribution was narrower than those of PF. Related Articles | Metrics

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Controlled Release of Acetochlor from Carboxylmethylcellulose Gels LI Jian-fa;LV Jin-hong;LI Fan-li 2008, 28 (04):  13-16.  Abstract ( 659 )   PDF (753KB) ( 837 )   Save Release of the herbicide acetochlor was controlled by encapsulating it into the gel carrier that was obtained from the crosslinking of carboxylmethylcellulose (CMC) with Fe3+ ions, which is beneficial for reducing contamination of herbicides. The required time for 50% of acetochlor released into water (t50) was used to compare the release rate. The results indicated that, the t50 values from CMC hydrogels were below 8h, but the values from dried gels were improved to 100h. The less amount of herbicide loading in gel formulations resulted in a slower release rate. The release data were analyzed with a controlled release model, and the results indicated that the release of herbicide from dried gels was dominated by a diffusion mechanism. IR spectrum confirmed the interaction between CMC macromolecules and acetochlor through hydrogen bonding. Related Articles | Metrics

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Purification and Structural Characterization of Xylobiose and Xylotriose Produced by Xylanase from Corncob Xylan ZHANG Jun-hua;YONG Qiang;XU Yong;YU Shi-yuan 2008, 28 (04):  17-20.  Abstract ( 628 )   PDF (687KB) ( 623 )   Save Xylobiose and xylotriose were separated from xylooligosaccharides produced by xylanase from corncob xylan by gel permeation chromatography on polyacrylamide gel Bio-Gel P-2 by FPLC system. High purities of xylobiose (about 97%) and xylotriose (about 94%) were obtained by twice separation on Bio-Gel P-2. The structures of xylobiose and xylotriose were determined by HPLC, electrospray ionization mass spectrometry(ESI-MS)and 13C NMR spectroscopy. The results showed that the molecular weights of xylobiose and xylotriose were 282 and 414, respectively, and there were no substitutions of 2-O- or 3-O-acetyl, arabinose,or 4-O-methylglucuronic acid. According to the structure of corncob xylan, the xylobiose and xylotriose prepared by xylanase from corncob xylan were β-D-(1→4)-xylopyranosyl-(14)-D-xylopyranose and β-D-(1→4)-xylopyranosyl-(1→4)-D-xylopyranose-(1→4)-D-xylopyranose,respectively without any substitution. Related Articles | Metrics

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Study on Chemical Structure of Urea-formaldehyde Resin with Low Formaldehyde Emission by 13C CP/MAS NMR ZHU Li-bin;GU Ji-you 2008, 28 (04):  21-24.  Abstract ( 662 )   PDF (548KB) ( 510 )   Save Based on the evaluation of the chemical structures of three kinds of urea-formaldehyde(UF) resin with low formaldehyde emission by 13C NMR, the technique of 13C CP/MAS NMR was applied to study the chemical structure of UF resins. Results indicated that the curing procedure of three kinds of UF resin with low formaldehyde emission was diverse in different curing system, the structure of cured resin was different as well. Without hardener, the cross-linkage degree of UF resin was lower, the content of methylol of cured UF resin was the higher and formaldehyde emission was increased. The hardener accelerated the curing reaction. the content of methylol was decreased. In three kinds of curing system, the content of methylol was the highest for UF-3; it was the lowest of 0.0582 for UF-2 with ammonium chloride as curing agent; for UF-1, it was the lowest without hardener and composite curing system of 0.0784 and 0.0713 respectively. The curing reaction of different kinds of UF resin was different in different curing system, the structure of cured resin, mechanical properties and formaldehyde emission were different too. Related Articles | Metrics

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Comparative Pulping Properties of Eucalyptus urograndis×E.grandis and Acacia mangium Willd. Woods Using P-RC APMP Process CHEN Nai-ming;DENG Yong-jun;HAN Shan-ming;JIAO Jian;FANG Gui-gan 2008, 28 (04):  25-30.  Abstract ( 800 )   PDF (1055KB) ( 626 )   Save Pulping properties of Eucalyptus urograndis×E.grandis (E.u.×E.g.) and Acacia mangium Willd. wood chips were investigated by using preconditioning refinerchemical alkaline peroxide mechanical pulping(P-RC APMP) process. Specific refining energies were recorded and both physical properties and optical properties of pulps were evaluated. Results show that similar brightness of P-RC APMP pulps could be produced from both E.u.×E.g. and A.mangium wood chips. At the chemical dosage level of H2O2 4.0% and NaOH 3.5%, which is a very low chemical consumption, pulp brightness of both pulps was able to reach 75%ISO. The pulp yield of A. mangium wood chips was 3.0% higher than that of E.u.×E.g. wood chip. At the freeness level of 250mL Canadian Standard Freeness (CSF), pulps from A.mangium wood chips was much stronger than that from E.u.×E.g.. For example, the tensile strength of P-RC APMP pulp from A.mangium was above 26N·m/g, about 30% higher than that of E.u.×E.g. pulp; Further refining could improve chemimechanical pulp strength. For the same CSF level,pulping of A.mangium wood chips requires more refining energy than that of E.u.×E.g. wood chips. Related Articles | Metrics

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Phenolic Compounds from Barks of Platanus orientalis Linn. SI Chuan-ling;DENG Xiao-juan;WANG Dan;SU Yan-fang;LIU Zhong 2008, 28 (04):  31-33.  Abstract ( 675 )   PDF (357KB) ( 672 )   Save Study on the EtOAc participated fraction from the barks of Platanus orientalis Linn. led to the isolation of (+)-catechin, (-)-epicatechin, (+)-gallocatechin, (-)-epigallocatechin, kaempferol, quercetin, afzelin, isoquercitrin,[JP] astragalin-6″-O-gallate, isoquercitrin-6″-O-gallate and tyrosol by column chromatography over Sephadex LH-20. The structures of these phenolic compounds, which have not previously been isolated from its barks, were established on the basis of spectroscopic evidences. Related Articles | Metrics

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Synthesis of Bornyl Acetate from α-Pinene Catalyzed by Acidic Ionic Liquid JI Kai-hui;LIU Shi-wei;XIE Cong-xia;YU Shi-tao;LIU Fu-sheng;ZHOU Guang-qiang 2008, 28 (04):  34-38.  Abstract ( 847 )   PDF (945KB) ( 683 )   Save An acidic ionic liquid, namely (3-sulfonyl)propyltriethylamine hydrosulfate[HSO3-(CH2)3N(C2H5)3HSO4 was prepared and characterized by FT-IR,1HNMR and 13C NMR. Esterification of α-pinene catalyzed over the composite catalytic system of [N(Et)3CH2SO3HSO4-ClCH2COOH was studied. The influences of reaction factors,such as amount of acidic ionic liquid, reaction temperature, reaction time and proportion of reactants were investigated. The optimum conditions for α-pinene esterification were obtained as follows:n(α-pinene):n[N(Et)3(CH2)3SO3H]HSO4:n(chloroacetic acid):n(acetic acid) 5:0.6:5:14,reaction temperature 30℃, reaction time 10h. Under the above conditions, the conversion of α-pinene was 95.90% and the selectivity of bornyl ester was 45.07%. The reusability of the composite catalytic system was investigated. Under the optimum conditions, when the composite catalytic system was repeatedly used for 5 times, α-pinene conversion reached 87.4% and the selectivity of bornyl ester was 40.6%. Related Articles | Metrics

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Study on Antioxidative Activity of Toona sinensis(A. Juss.) Roem.Based on Bioassay-guided Method WANG Chang-lu;JIANG Shen-hua;CHEN Zhi-qiang;CHEN Mian-hua;WANG Yu-rong;LIU Chang-jin;ZHOU Qing-li;XIA Lian-fa 2008, 28 (04):  39-43.  Abstract ( 713 )   PDF (938KB) ( 634 )   Save Methanol extract of old leaves of Toona sinensis (A. Juss.) Roem. was separated into four subfractions of different polarities based on bioassay-guided method. The antioxidative activities and the related responsible compounds in T. sinensis were studied by evaluating reducing power, ferric reducing ability of plasma (FRAP) value and 1,1-diphenyl-2-picrylhydrazyl (DPPH)radical scavenging capacity of four subfractions with different polarities. The results showed that reducing power, FRAP value and DPPH radical scavenging capacity of ethyl acetate subfraction at a concentration of 50 mg/L had the strongest antioxidant activities of 467.53mg/g (ascorbic acid) Vc equivalents, 10578(μmol/L)/g FeSO47 H2O equivalents and92.84%, respectively. All these antioxidant values of ethyl acetate subfraction were much higher than BHT at the same concentration. The correlation study showed that the powerful antioxidative activity of T. sinensis was mainly resulted from high contents of flavonoids. The antioxidants mainly consist of four [JP2]flavonoid glucosides. These results laid a solid foundation for further researching and developing T. sinensis . Related Articles | Metrics

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Studies on Chemical Constituents and Antifungal Activity of Turkish Galls LIU Yan-lin;DENG Xu-ming;WANG Da-cheng;LEI Lian-cheng;HAN Wen-yu;ZHAO Rui-li;WANG Jiao-yu 2008, 28 (04):  44-48.  Abstract ( 708 )   PDF (891KB) ( 524 )   Save Chemical constituents of Turkish galls and their antifungal activities were studied. The constituents were isolated and purified by silica gel, Sephadex LH-20 column chromatography and preparative thin-layer chromatography,and their structures were elucidated by various spectroscopic methods.The method of minimal inhibitory concentration(MIC) was used to evaluate the antifungal activity of the extracts and compounds from Turkish galls. Seven compounds were isolated and their structures were identified as gallic acid (Ⅰ), m-digallic acid(Ⅱ), p-digalloyl acid(Ⅲ), methyl gallate(Ⅳ), ethyl gallate(Ⅴ), 1,2,3,6-tetra-O-galloyl-β-D-glucose(Ⅵ), and 1,2,3,4,6-penta-O-galloyl-β-D-glucose(Ⅶ). The EtOAc extractive exhibits the strongest bacteriostatic activity. Compounds Ⅲ and Ⅴ are isolated from this gall for the first time. Related Articles | Metrics

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Separation of Endoxylanases from Trichoderma viride by Selective Adsorption with Oat Xylan JIANG Hua;BO Kai-jing 2008, 28 (04):  49-54.  Abstract ( 676 )   PDF (1043KB) ( 485 )   Save Endoxylanases from Trichoderma viride were separated from each other by selective adsorption with insoluble oat xylan. Based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), both xylanases reached electrophoretically pure. The molecular weights of the bounded (XynⅡ) and the unbounded (XynⅠ) components were 26.5 and 29.5ku respectively, and their Km s toward birch xylan were 1.73 and 3.16g/L, respectively. The hydrolysates from oat xylan using XynⅠ,XynⅡ and their mixture for hydrolysis were analysed by HPLC. It was showed that Xyn Ⅰ hydrolyzed mainly the unsubstituted regions of oat xylan, and hydrolytes were high xylooligosaccharides; whereas XynⅡexhibited greater catalytic versatility than XynⅠand were able to attack substituted regions of the polysaccharide and showed greater activity to low xylooligosaccharides than XynⅠ to give xylobiose as the main hydrolysate. The purified xylanases were acidic enzymes. XynⅡ was sensitive to pH value, and XynⅠ was stable in the wide range of pH values. The optimal reaction temperatures of XynⅠ and XynⅡ were 45 and 55℃ respectively, and their optimal pH values were 4.5 and 5.5 respectively. Related Articles | Metrics

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Study on Components and Anti-microbial Functions of Wheat-stalk Vinegar ZHOU Jian-bin;YE Han-ling;WEI Juan;ZHANG Qi-sheng 2008, 28 (04):  55-58.  Abstract ( 633 )   PDF (668KB) ( 728 )   Save GC-MS was used to analyze the components of wheat-stalk vinegar, and the anti-microbial functions were studied. The results showed that wheat-stalk vinegar was a liquid mixture containing 70 kinds of components. The main components of wheat-stalk vinegar included phenolics (28.68%), organic acids (22.16%), ketones (21.22%), alcohols (4.00%), aldehydes (1.44%), etc. The results of inhibition-circle experiments showed that the diameters of the inhibition circles for two kinds of bacteria (Escherichia coli and Staphylococcus aureus) were 10.2 and 9.2mm respectively. Both of the two contrast samples did not have inhibition circles, which demonstrated that wheat-stalk vinegar has definite anti-microbial effects toward E.coli and S. aureus, and it is a favorable antimicrobial agent. Related Articles | Metrics

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Structural Analysis,Characterization and Physico-chemical Properties of Composite-modified Starch SHI Jun-you;GU Ji-you;TU Huai-gang;WANG Shu-min 2008, 28 (04):  59-64.  Abstract ( 654 )   PDF (1300KB) ( 818 )   Save The occurrence of grafting copolymerization reaction was proved by analytical means such as FT-IR, X-ray diffraction, SEM, etc. on the obtained composite-modified starch. The physical and chemical properties of the starch were systemically analyzed and described by conventional chemical analysis method. The result of FT-IR analysis showed that there was copolycondensation between acid-hydrolyzed and oxidized starch and acrylamide. X-ray diffraction detected that acid-hydrolysis,oxidation and grafting copolymerization of corn starch mainly occurred in the amorphous area. The result of SEM revealed that the granularity of the modified starch could be intact, but the surface of granule became rough. The results showed that composite-modified starch had the properties such as big sedimentation volume, low pasting-temperature, high hot-pasting stability and low cold-paste viscosity. Related Articles | Metrics

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Analysis on Pyrolysis Products from Black-liquor Solid and Technical Lignin LIU Jiang-yan;WU Shu-bin;GUO Yi-li 2008, 28 (04):  65-70.  Abstract ( 646 )   PDF (1080KB) ( 810 )   Save The pattern of pyrolysis products distribution from purified technical alkali lignin and black-liquor solid under different temperatures were studied. The composition of liquid product (pyrolysis oil) and solid residue from pyrolysis process were analyzed by pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), elementary analysis and ICP plasma emission spectrum. Results showed the maximum yield of pyrolysis oil was obtained at 600℃, and the pyrolysis oil from alkali lignin was higher than that from black-liquor solid. The chemical composition of pyrolysis oil was very complicated, and components of pyrolysis oil from purified technical alkali lignin had lots of difference from that of black-liquor solid. The pyrolysis oil from purified technical alkali lignin was mainly consisted of low molecular phenolics, ketones, organic acids,etc. The relative contents of phenolics and organic acids in pyrolysis oil from technical lignin were obviously higher than those from black liquor solid. The relative content of laevoglucose was found to be higher in pyrolysis oil from black liquor solid than that from technical lignin, but biphenyl structure compound was detected in pyrolysis oil from technical lignin, which might be generated from condensation of intermediate products. The results give us the hint that it may be possible to control the composition of pyrolysis oil by suitable pretreatment of the black liquor. Related Articles | Metrics

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Research on the Effect of Refining Chinese Lacquer on Its Rheological Property ZHANG Fei-long;SHI Yu;ZHANG Wu-qiao;LI Xin 2008, 28 (04):  81-85.  Abstract ( 689 )   PDF (930KB) ( 718 )   Save The refining process of raw lacquer was studied by utilizing zymological principle and rheological theory. The results show that system temperature, refining time and shearing strength have effect on rheological property:1)The longer the refining time, the higher is the lacquer viscosity; 2)Effect of temperature on rheological property is complicated. In low-temperature range(T <45.8℃), as temperature is increasing, fluidity of lacquer is also increasing, viscosity is decreasing. When tempera-ture is further increasing (T>51.3℃), viscosity begins to increase again. As temperature keeps on increasing, viscosity then begins to decrease. At 46.8℃, viscosity reaches its minimum value; 3)The change of viscosity of lacquer is also depended on agitation speed. At low speed, viscosity is increasing as stirring rate increasing. At the speed of 150 r/min, system reaches the minimum viscosity. Afterwards, viscosity is increasing with stirring speed increasing. Related Articles | Metrics

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Study on Influencing Factors to Quality Stability of p-Menthane Hydrogen Peroxide (PMHP) CHEN Yu-xiang;LEI La;ZHAO Zhen-dong;LI Dong-mei;LIU Xian-zhang 2008, 28 (04):  71-75.  Abstract ( 725 )   PDF (829KB) ( 514 )   Save Variation relationships were studied between quality indexes such as mass fraction, acid value, refractive index, and viscosity of p-menthane hydrogen peroxide (PMHP) products with storage days, and major influencing factors to the quality stability of PMHP were studied as well. The results shown that the correlation coefficients (rt) of PMHP mass fraction, acid value, refractive index, and viscosity to the storage days are -0.8807, 0.9867, 0.9348 and 0.2236, respectively; the correlation coefficients (rx) of variations of acid value, refractive index, and viscosity to the variation of PMHP mass fraction in the storage are -0.9454, -0.9695 and -0.4240, respectively. The results also shown that the acid value is an important quality index, and that the resistance and formation of more acidic matters in the product is a key influencing factor to the quality stability of PMHP. The initial acid value is suggested to be regulated to a suitably lower level as a key influencing factor, so that it would effectively reduce the variations of acid value and PMHP mass fraction under storage, then increase the quality stability. Related Articles | Metrics

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Modification on Synthesis Process of α-Terpinol from Catalytic Hydration of Pinene over Solid Sulfonic Acid LI Jia-qi;YAN De-peng;XU Qiong;YIN Du-lin 2008, 28 (04):  76-80.  Abstract ( 681 )   PDF (949KB) ( 690 )   Save Kinetic effects on one-step hydration of pinene in acetone as solvent over D-72 solid sulfonic acid resin as catalyst were investigated. It was found that the amounts of solvent and water possessed strong effect to the catalytic performance, and the selectivity of both α-terpinol and total alcohols was decreased with the increasing of the conversion of pinene under different volume ratio of acetone to pinene. The selectivity of α-terpinol and the selectivity of total alcohol got up to 50 % and 60 % respectively when the reaction temperature was 60 ℃, volume ratio of acetone to α-pinene was 2:1, molar ratio of α-pinene to water was 1:4, under suitable control of reaction time. Related Articles | Metrics

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Study on Treatment of Auto-catalyzed Ethanol-water Pulping Waste Liquor of Aspen by Distillation-ultrafiltration CUI Xin;ZHOU Jing-hui;YANG Rui-feng 2008, 28 (04):  93-98.  Abstract ( 578 )   PDF (1003KB) ( 536 )   Save The waste liquor of auto-catalyzed ethanol-water pulping of aspen had complex components and high value of by products. Ethanol and lignin products were separated from waste liquor by distillation-ultrafiltration in order to reduce degree of waste liquor pollution markedly. The effects of different factors on the process of separation were studied to confirm optimal technical conditions. The results showed that the optimal conditions were: volume ratio of concentration 0.5, Mr of interception 10000, pressure 0.20MPa, stirring rate 600 r/min, temperature 30 ℃. This method could recover useful components effectively and reduce degree of waste liquor pollution markedly. Related Articles | Metrics

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Study on Quantitative Analysis and Extraction of Total Saponins from Schefflera arboricola Hayata LI Kun-ping;PAN Tian-ling;BI Yong-guang;LIN Rui-qing 2008, 28 (04):  99-102.  Abstract ( 708 )   PDF (766KB) ( 748 )   Save A quantitative analysis method for total saponins from Schefflera arboricola Hayata was established, and the extraction process was optimized by orthogonal test. The results show that using a colorimetric assay with oleanolic acid as reference substance, 5% vanillin-acetic acid solution-HClO4 as color-producing reagent, heated at 70℃ for 15min and detected at 546 nm wave length,the measurement results are stable in the initial 40min, and there is a good linearity (r=0.99933, n=6) for the total saponins concentration from 0.002 to 0.02g/L; and the average recovery ratio is 101.2%with relative standard deviation (RSD) less than 0.86% (n=6). For the extraction process, selecting 50%(volume fraction) ethanol as solvent, controlling the solid-liquid ratio 1:15(g:mL), reflexing twice in 80℃ water bath and each time for 120min, the yield of total saponins reached 12.17mg/g raw material. Related Articles | Metrics

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Study on Ultrasound-assisted Extraction of Diosgenin from Dioscorea zingiberensis C.H.Wright ZHANG Li-ming;ZHAO Xi 2008, 28 (04):  103-107.  Abstract ( 602 )   PDF (966KB) ( 660 )   Save Ultrasound-assisted extraction of diosgenin from rhizome of Dioscorea zingiberensis C.H.Wright was optimized. Compared with the traditional spontaneous fermentation, the effects of operating conditions were studied according to single factor and orthogonal design. The optimal condition was achieved as follows:crude powder of D.zingiberensis 10g materials to solvent ratio 1:10 (g:mL), 70% alcohol, extracted twice under ultrasonic power of 100W, each time for 30min. Under the above conditions, diosgenin can be obtained at the yield of 2.57%. By contrast, the maximum yield of diogenin is only 2.13% by traditional method after spontaneous fermentation for 24 h. Therefore, ultrasonic-assisted technology was more effective with the advantages of much shorter extracting time and higher yield of diosgenin. Related Articles | Metrics

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Study on Microwave-assisted Synthesis of Isopropyl Cinnamate Catalyzed by Macroporous Resin LI Yu;HUANG Wei-qian;YANG Jin-lan;TAN Wei-jun;TAO Wen-cheng;CHEN Jing-wen;LIANG Dan 2008, 28 (04):  108-111.  Abstract ( 646 )   PDF (794KB) ( 566 )   Save Microwave-assisted synthesis(MAS) was integrated with macroporous resin catalysis (MRC) to prepare isopropyl cinnamate from cinnamic acid. The preparation process was investigated and the optimum synthetic conditions were as follows: cinnamic acid 2 g, molar ratio of cinnamic acid to isopropyl alcohol 1:10, reaction temparture 105℃, microwave power 400W, CAT-601 resin as catalyst, dose of macroporous resin 25 % of the reagents, reaction time 12.5 min. The yield of isopropyl cinnamate by the new developed process was 39.2%. The catalytic property of regenerated catalyst was stable. Related Articles | Metrics

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Recent Research Progresses on Alkaloids from Genus Daphniphyllum WANG Kui-wu;ZHANG Hong;SHEN Lian-qing 2008, 28 (04):  123-130.  Abstract ( 657 )   PDF (1516KB) ( 783 )   Save Alkaloids are natural organic compounds that were the most early studied by scientists and most of them have good bioactivities. Plants of the genus Daphniphyllum are known to metabolize structurally diversified Daphniphyllum alkaloids with highly complex polycyclic skeleton. Daphniphyllum alkaloids have been the challenging subjects in biogenetic and synthetic programs of natural products. Some of these alkaloids exhibited cytotoxic activities against several tumor cell lines. Along with the developments of isolation and structure elucidation techniques of phytochemistry,more and more compounds of this genus were isolated and identified. More than 70 compounds were obtained from this genus of plants in recent research.In order to assist the medicinal application of this genus of plants,progresses made in this field were systemically reviewed, which will be benefitial for further research and development of these compounds. Related Articles | Metrics

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Analysis on High-grade Resource Utilization of Eucalyptus urophydis Bark by Py-GC-MS PENG Wan-xi;WU Shu-bin;WU Yi-qiang;ZHANG Dang-quan;CHEN Hong 2008, 28 (04):  86-92.  Abstract ( 680 )   PDF (1145KB) ( 737 )   Save Pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) was used to analyze the pyrolysis product of Eucalyptus urophydis bark and its benzene-ethanol extractives. The main and abundant constituents of 590℃ pyrolysis product of E.urophydis bark were acetic acid (17.66%), 1,6-anhydro-β-D-glucopyranose (16.53%), carbon dioxide (15.75%), butane (10.22%), 1-hydroxy-2-propanone (10.19%), 1-propanol (9.73%), etc. The main and abundant constituents of pyrolysis product of benzene-ethanol extractives of E. urophydis bark were 9,12-octadecadienoic acid (Z,Z)- (7.14%), n-hexadecanoic acid (6.89%), 8-propoxy-cedrane(6.65%), 4-hydroxy-3,5-dimethoxy-benzaldehyde(5.81%), 2,6-dimethoxy-phenol(5.79%), ergosta-4,6,22-trien-3α-ol (5.68%), 2-methoxy-4-vinylphenol (5.03%), 2-methoxy-4-(1-propenyl)-phenol, (4.90%), carbon dioxide (4.32%), stigmastan-3,5-diene (3.35%), 2,3,5,6-tetrafluoroanisole (3.13%), 2-methoxy-phenol(3.09%), etc. Related Articles | Metrics

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Progress of Research on Bio-activity and Applications of Pimaric-type Resin Acids CHEN Yu-xiang;ZHAO Zhen-dong;LI Xing-di;LI Dong-mei;BI Liang-wu 2008, 28 (04):  118-122.  Abstract ( 694 )   PDF (812KB) ( 806 )   Save Pimaric-type resin acid is a kind of important resin acid with a special structure, in which there are both a methyl group and a vinyl group at C-13 position. Most isomers of pimaric-type acids possess bio-activity, such as anti-bacterial, diminishing inflammation, anti-microbe, pesticidic, decreasing cholesterol, and anti-cancer activities. Recent progresses of research and application for pimaric-type resin acid at home and abroad are reviewed. Especially, their bio-activities as pesticides and medicines, and applications have been introduced. The developing prospects of pimaric-type resin acid have also been discussed. Related Articles | Metrics

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Determination of Trace Iron in 2,3,4,4′-Tetrahydroxybenzophenone by Graphite Furnace Atomic Absorption Spectrometry WANG Wei-ru;HUANG Jia-ling;WANG Jian-sheng;JING Xia;CHEN Wen-wen; 2008, 28 (04):  112-114.  Abstract ( 857 )   PDF (559KB) ( 619 )   Save A determination method of trace iron in 2,3,4,4'-tetrahydroxybenzophenone by graphite furnace atomic absorption spectrometry is established. The optimum condition of graphite temperature and electric current of hollow cathode lamp were investigated. Determination conditions were: drying temperature 120℃, ashing temperature 700℃, atomization temperature 2400℃,electric current of hollow cathode lamp 3mA. There was a good linearity in range of 2.5-10.0μg/L. Relative standard deviation(RSD) was 1.99%, and recovery rate was 94.2%. This method was accurate and reproducible, and suitable for determination of trace iron in 2,3,4,4'-tetrahydroxybenzophenone. Related Articles | Metrics

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Preliminary Study on Chemical Structure of Pine Nut Kernel Polysaccharide LIU Rong;SUN Fang;CHEN Xiu-li;WANG Xiang-hong 2008, 28 (04):  115-117.  Abstract ( 715 )   PDF (568KB) ( 736 )   Save Four polysaccharide fractions (PNP1-a,PNP1-b,PNP2-a,PNP3-a) were isolated from the kernel of Pinus koraiensis Sieb.et Zucc by hot water extraction, ethanol precipitation and purification followed by DEAE-cellulose and gel-permeation column chromatographies. The molecular weights of the 4 fractions were 10.2×104, 1.43×104, 11.0×104 and 16.3×104 respectively. The unit monosaccharides of PNP1-a were identified as rhamnose and glucose at the ratio of 1.00:2.57; and the unit monosaccharide of PNP1-b was identified as arabinose and glucose at the ratio of 1.00:4.03; PNP2-a and PNP3-a were both consisted of glucose. The structures of the fractions were analysed through FT-IR, ultraviolet and NMR spectroscopies, the results showed that monosaccharides of PNP1-a, PNP1-b, PNP2-a and PNP3-a were all of β-pyranose configuration. Related Articles | Metrics