Table of Content

30 April 2008, Volume 28 Issue 2 Previous Issue    Next Issue

研究报告

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Studies on Isolation, Identification and Biological Activitiy of A Neutral Glycoprotein from the Stems of Avicennia marina(Forsk.)Vierh. FANG Xu-bo;CHEN Xiao-e;JIANG Bo;WANG Xiao-lan;YUAN Yao-ping 2008, 28 (2):  27-32.  Abstract ( 569 )   PDF (967KB) ( 628 )   Save HAM-3-IIa, a neutral polysaccharide fraction, was obtained from Avicennia marina(Forsk.) Vierh. by a series steps of extraction, isolation and purification. The purified HAM-3-IIa was proved to be homogenous by HPGFC and gel column chromatography. Its molecular weight was 97600. HAM-3-IIa was regarded as neutral glycoprotein with 4.9% protein and 95% carbohydrate. The carbohydrate fraction was composed of arabinose, galactose and xylose. Linkage between sugars and amino acids was shown to be O-glycol-Ser bond by β-elimination reactions. HAM-3-IIa expressed potent anti-complementary activity via classical and alternative pathways with the increase of activity proportional to dosage. It was confirmed from the study that the activity of polysaccharide was not due to the presence of microbial contamination during the purification processes. Related Articles | Metrics

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Effects of Various Acidic-alkalinic Conditions on Texture Properties of Almond Gel WANG Sen;XIE Bi-xia;ZHONG Qiu-ping;LI Yi-na 2008, 28 (2):  119-123.  Abstract ( 591 )   PDF (1225KB) ( 618 )   Save The variation patterns of texture properties of almond gel under various acidic and alkalinic conditions are studied by using TA-XT21 texture profile analysis. The results show that the differences among levels under various acidic and alkalinic conditions are notable. The F values of hardness, fracturability, adhesiveness, gumminess, chewiness and resilience of the almond gel under various acidic and alkalinic conditions are 12.98909, 6.036852, 37.31764, 17.23481, 16.072 and 12.53875 respectively, and the differences are extremely significant. The F values of springiness and cohesiveness are 0.058577 and 1.113238 respectively, which are not significant. The variation patterns of texture properties of almond gel under various acidic and alkalinic conditions exhibit diversity of difference. Related Articles | Metrics

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Structural Characteristics of Sulfonated Wheat Straw Lignin from Alkali Pulping and Its Performances as Concrete Water-reducer PANG Yu-xia;YANG Dong-jie;QIU Xue-qing;DENG Guo-song 2008, 28 (2):  67-72.  Abstract ( 606 )   PDF (1196KB) ( 769 )   Save The performances of sulfonated wheat straw lignin (SWSL), which is a sulfonated product of wheat straw lignin extracted from alkali pulping, used as concrete water-reducer were studied. When the dosage is 0.25% (based on concrete), the water-reducing ratio of SWSL reaches 13.5% which is higher than that of calcium lignosulfonate (CLS) obtained from sulphite pulping; but the 3 and 7d compressive strengths of concrete are only 113% and 105% respectively, which are lower than those of CLS. Further researches indicate that, in the alkali solution of cement paste, SWSL has good foaming property and foam stability, which result in high water-reducing ratio. However the foam of SWSL solution is large and non-homogeneous, with the largest bubble diameter of 2mm, which leads to decrease of the density of hardened mortar blended with SWSL. The content of pores with a diameter less than 0.01mm was relatively low; while the content of pores with a diameter between 0.01-0.05mm was high. Thus the compressive strength of hardened concrete was reduced. The sulfonation degree of SWSL is 1.1mmol/g and its molecular weight is 4424 only, which are all lower than those of CLS. The relatively low sulfonation degree is the reason that the dispersibility of SWSL is not comparable with CLS. Related Articles | Metrics

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Antitumor Constituents from the Leaves of Aquilaria sinensis(Lour.)Gilg WANG Hong-gang;ZHOU Min-hua;LU Jing-jing;YU Bo-yang 2008, 28 (2):  1-5.  Abstract ( 1155 )   PDF (772KB) ( 1833 )   Save Based on screening of antitumor activity, antitumor constituents in the crude extract from the leaves of Aquilaria sinensis(Lour.) Gilg, were isolated and purified by various chromatographic methods and were identified on the basis of spectral analysis and physico-chemical characters. Ten compounds were identified as 5-hydroxy-7,4'-dimethoxyflavone(1), luteolin-7,3',4'-trimethyl (2), luteolin-7,4'-dimethyl(3), genkwanin(4), luteolin(5), 3'-hydroxygenkwanin(6), 2-O-α-L-rhamnopy-ranosyl-4,6,4'-trihydroxybenzo-phenone(7), 4-hydroxybenzoic acid(8), β-daucosterol(9), 7α-hydroxysitosterol(10), respectively. The novel compound 7 was found for the first time. Compounds 1-6 and 8, 10 were isolated from this plant for the first time. Related Articles | Metrics

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Preparative Separation and Purification of Piperine from Piper nigrum Linn.by High-speed Counter-current Chromatography WANG Xiao;YUAN Jin-peng;GENG Yan-ling;LI Fu-wei;WANG Dai-jie;LIU Jian-hua 2008, 28 (2):  6-10.  Abstract ( 679 )   PDF (396KB) ( 612 )   Save Piperine, a major plant alkaloid presenting in pepper, was successfully separated and purified from the crude extract of Piper nigrum Linn. by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of petroleum ether (60-90℃)-ethyl acetate-methanol-water (1:0.8:1:0.8, volume ratio). The upper phase was used as stationary phase, while the lower phase was used as mobile phase. From 300 mg of crude extract, 65.2 mg of piperine was obtained at 99.1% purity in one-step separation. The structure of the target compound was identified by EI-MS, 1H NMR and 13C NMR. Related Articles | Metrics

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Study on Effect of Branched-chain Alcohol on Low-temperature Properties of Biodiesel MENG Zhong-lei;LI Xiang-yu;JIANG Jian-chun 2008, 28 (2):  11-15.  Abstract ( 613 )   PDF (828KB) ( 623 )   Save Soybean oil, methanol and branched-chain alcohol were used to produce biodiesel which contains branched-chain esters.The branched-chain alcohol used is one of these alcohols: isopropanol,isobutyl alcohol, sec-butyl alcohol. Isopropanol has the best reaction property among these alcohols.The effects of reaction time,temperature, catalyst dosage,isopropanol and methanol molar ratio on content of isopropyl esters(IPE) were researched.The GC content of IPE could be more than 50% in this experiments. However, when IPE content was over 20%, separation of glycerin from esters was difficult. The properties of the product with different IPE content were mensurated and its viscosity was higer than fatty acid methyl esters, while condensation point(CP) and cold filter plugging point (CFPP) were decreased from 5 to 8℃ compared with FME. Related Articles | Metrics

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Study on Synthesis of p-Menthanediamine from Turpentine Derivative Terpin Hydrate FENG Zhi-yong;LI Dong-mei;ZHAO Zhen-dong;BI Liang-wu;WANG Jing;GU Yan 2008, 28 (2):  16-20.  Abstract ( 722 )   PDF (831KB) ( 734 )   Save A new route to synthesize p-menthanediamine (MDA) from terpin hydrate was conducted in the paper, through which di-azido-p-menthane is synthesized at an average yield 73.1% by reaction between terpin hydrate and sodium azide catalyzed by sulphuric acid followed by hydrogenation catalyzed by Lindlar catalyst to give MDA at an average yield of 86.3%. The total yield is 63.1% based on the terpin hydrate. The purified product MDA was analyzed with GC, and its chemical structure was identified through GC-MS, FTIR, 1H NMR. Thereafter, the product was applied as a curing agent to prepare an epoxy-resin. Results showed that it has properties similar to the marketed p-menthane-1,8-diamine. The synthetic route was proved to be effective and feasible for the preparation of MDA. Related Articles | Metrics

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Adsorption of Mo(Ⅵ)on Collagen Fiber Immobilized Bayberry Tannin WANG Ru;LIAO Xue-Pin;ZENG Tao;PENG Na;SHI Bi 2008, 28 (2):  21-26.  Abstract ( 660 )   PDF (938KB) ( 726 )   Save The adsorption behaviors of Mo6+ on collagen fiber immobilized bayberry tannin(IBT), a new kind of adsorbent, were investigated. It was found that the influence of temperature on adsorption capacity of Mo6+ is insignificant, but the effect of pH value on the adsorption was remarkable. The adsorption capacity of Mo6+ was increased with the decrease of pH value. These facts implies that adsorption is based on electrostatic association between adsorbent and polymeric anions of Mo6+. At pH value 2.0 and 303K, the adsorption capacity of Mo6+on 0.100g adsorbent was 82.4mg/g in 100 mL of 100.0mg/L Mo6+ solution. The adsorption isotherms can be well described by Freundlich equation. The adsorption rate of the adsorbent to Mo6+ was very fast at the beginning, and reached adsorption equilibrium around 600min. The adsorption kinetics can be well described by the pseudo-second-order-rate model and the adsorption capacities calculated by this model are very close to those experimentally determined. The adsorbent can be regenerated by using 0.02mol/L sodium ethylenediamine-tetraacetate(EDTA-Na4) as desorption agent after adsorption of Mo6+. The adsorbent also showed satisfactory adsorption selectivity to Mo6+ in Mo6+-Ni2+ and Mo6+-Cu2+ mixture solutions at pH value 2.0, because these metal ions have different adsorption mechanisms on IBT and therefore, to be adsorbed at different pH value ranges. Related Articles | Metrics

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Flavonoids from the Leaves of Sabina vulgaris Antoine ZHAO Jun;YAN Ming;HUANG Yi;HE Wen-yi;ZHAO Yu 2008, 28 (2):  33-37.  Abstract ( 689 )   PDF (706KB) ( 727 )   Save Chemical constituents in the leaves of Sabina vulgaris Antoine were studied. Nine flavonoids were isolated and purified by extraction and different kinds of column chromatography, and their structures were elucidated as cupressuflavone(Ⅰ), cupressuflavone 4',4'''-dimethyl ether(Ⅱ), amentoflavone(Ⅲ), podocarpusflavone A(Ⅳ), catechin(Ⅴ), quercetin(Ⅵ), isoscutellarein 7-O-β-D-xylopyranoside (Ⅶ), myricetin 3-O-β-D-glucoside (Ⅷ), rutin(Ⅸ). Compounds Ⅰ, Ⅱ, Ⅴ, Ⅶ, Ⅷ and Ⅸ were obtained from this plant for the first time. Compounds Ⅷ and Ⅸ were isolated from Sabina genus for the first time. All of isolated compounds were tested for their antioxidative activities by 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH·) scavenging assay. It was found that compounds Ⅴ and Ⅵ showed antioxidative activity close to that of positive control, L-ascorbic acid, and the flavonoids glycosides (Ⅶ, Ⅷ and Ⅸ)are more active than the biflavones (Ⅰ, Ⅱ, Ⅲ and Ⅳ). Related Articles | Metrics

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Rheological Properties of Gum from Seed of Nicandra physaloides(L.)Gaertn TU Guo-yun;WANG Zheng-wu;GU Jin 2008, 28 (2):  38-42.  Abstract ( 647 )   PDF (1037KB) ( 901 )   Save The fundamental rheological properties of gum from seed of Nicandra physaloides (L.) Gaertn and the effects of factors, such as concentration(g/L, the same below), metal ions, sugar, standing time, pH value, temperature, freezing-thawing treatment on rheological properties were researched with Brook field RVDV-Ⅲ rheometer. Results indicated that gum solution had typical shear-thinning property, and the rheological properties were influenced by temperature, shearing rate, pH value, freezing-thawing treatment, etc. It was found that the gum solution investigated behaved as non-Newtonian shear-thinning fluid. With the increase of gum concentration(above 2 g/L), the consistency coefficient increased while the viscosity index decreased. The thixotropic response became stronger when gum concentration was increased. The increasing of temperature could reduce the viscosity of gum and the temperature dependence of η could be expressed by a relation of the Arrhenius equation. At pH value 3, the highest viscosity of aqueous solution (5 g/L) was 0.152 Pa·s, while strong acid and strong base resulted in a decrease in viscosity. Bivalent metal ions obviously improved the viscosity of gum solution, and the thickening effect was positively correlated to the concentration of metal ions. At the same concentration, the thickening effect of sucrose excelled glucose. Related Articles | Metrics

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Studies on Seperation of Sterols from Ginkgo biloba L.by Molecular Distillation and Recrystallization WANG Cheng-zhang;YE Jian-zhong;ZHENG Guang-yao;ZHANG Zhi-jie;SHEN Zhao-bang 2008, 28 (2):  43-47.  Abstract ( 665 )   PDF (875KB) ( 798 )   Save Lipid paste was extracted with petroleum ether from Ginkgo biloba L. leaves. Fatty acids and their esters, wax etc. were separated from sterols by saponification,extraction and refrigeration. The yield of sterols was 0.03%-0.08% by molecular distillation and recrystallization. Chemical components of sterols from G. biloba leaves were analyzed by GC-MS. Seventeen compounds were separated in which eight sterols were identified, which amounted to 97.633% of total peak area. These are β-sitosterol(67.984%),ergosta-8-en-3β-ol(10.624%), stigmastan-3β-ol (10.065%),stigmasta-5,24-dien-3β-ol,(3β,24Z)(5.255%),stigmasta-4,22-dien-3β-ol(1.926%),ergosta-5,8,22-trien-3β-ol,(3β,22E)(0.618%),fucosterol(0.595%)and α-sitosterol(0.566%). Among ketones(1.066%) there were 13α-androsta-5,7-dien-3-one, 17,19-diacetoxy-4,4-dimethyl(0.336%),17α-acetoxypregnenolone(0.730%); Except β-sitosterol, all other sterols were first reported in G. biloba leaves. Related Articles | Metrics

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Synthesis of Epoxy Fatty Acid Methylesters and Preliminary Exploration on Their Pour-point Depressing Properties NIE Xiao-an;JIANG Jian-chun;CHEN Shui-gen;CHANG Xia;ZHONG Yuan 2008, 28 (2):  48-52.  Abstract ( 670 )   PDF (932KB) ( 791 )   Save The synthesis technology of epoxy fatty acid methylesters was studied. By gas-chromatography and chemical analysis, the best condition of the synthesis technology was obtained as follows: fatty acid methylester 100g, phosphoric acid 0.6mL, formic acid 9mL, petroleum ether 50mL,reaction temperature 65℃, reaction time 3.5 h. The properties of epoxy fatty acid methylesters were as follow: epoxy value 4.89%, acid value 0.2mg/g,iodine value 9-10g/100g, viscosity 5.87mm2/s. Through the test on pour-point depressing properties of biodiesel by adding epoxy fatty acid methylester, it was found that the epoxy product could reduce cold filtering point of biodiesel 3℃,but had no effect on freezing point. Related Articles | Metrics

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Effect of Aeration on Cellulase Production by Trichoderma reesei HANG Zhi-xi;RAO Qing-long;YU Shi-yuan 2008, 28 (2):  53-57.  Abstract ( 488 )   PDF (1031KB) ( 746 )   Save The effect of aeration on cellulase production by Trichoderma reesei was studied with 10g/L paper pulp. At 28℃, with the impeller speed of 250r/min, and pH value 4.8, the aeration was either unadjusted or adjusted in order to control dissolved oxygen tension (DOT). The experiments were carried in a 10-L steam sterilizable bioreactor, mycelium consistence and cellulase activity were mensurated. The results showed: when aeration was unadjusted, DOT was either below the critical DOT or too high, which was not favorable to the growth of mycelium. When DOT was unadjusted, the best value of mycelium consistence was 2.77g/L, the best value of filter paper enzyme activity (FPA) was 2.80IU/mL.By adjusting aeration, the DOT at 20%-30% was most favorable to the growth of mycelium, the best value of mycelium consistence reached 3.12g/L,which was 12.6% higher than that of unadjusted aeration, FPA reached 3.55IU/mL at 76h, which was 26.8% higher than that of unadjusted aeration. Related Articles | Metrics

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Graft Copolymerization of Glycidyl Methacrylate with Eucalyptus Pulp Induced by Fe2+-H2O2-thioureadioxide Redox System HUANG Jun;ZHAI Hua-min 2008, 28 (2):  58-62.  Abstract ( 700 )   PDF (1060KB) ( 718 )   Save Graft copolymerization of bleached eucalyptus pulp with glycidyl methacrylate (GMA) induced by Fe2+-H2O2-thioureadioxide redox system was studied in detail. The mechanism of this initiator system was discussed primarily; the effects of reaction temperature and time, hydrogen peroxide and thioureadioxide dosages, monomer concentration and liquor ratio were characterized by the grafting rate, grafting efficiency and monomer conversion, and the chemical structure of grafted fiber was identified by FT-IR. Results showed that the addition of thioureadioxide can help to produce more radicals, which react with cellulose to obtain cellulose macromolecule radicals and thus proceed the graft copolymerization successfully. Proper increases of temperature, hydrogen peroxide dosage, proper decrease of liquor ratio and proper maintaining of thioureadioxide dosage are beneficial to the grafting rate and monomer conversion. Graft copolymerization can be proceeded successfully in a short time. Grafting efficiency could be generally maintained at 97% to 99%, and was almost not affected by any factor. Extremely insignificant amount of homopolymer was produced during the grafting process. Related Articles | Metrics

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Study on Antimicrobial Activities of Extracts from Eucommia ulmoides Oliv. Leaves JI Zhi-ping;SU Yin-quan 2008, 28 (2):  63-66.  Abstract ( 607 )   PDF (347KB) ( 734 )   Save In order to find new antimicrobial substance, antimicrobial activities of 70%(volume fraction) ethanol extract of Eucommia ulmoides Oliv. leaves and its fractionated extracts were tested. The result showed that ethanol extract and ethyl acetate extract had inhibitory effect toward bacteria and fungi, while ethyl acetate extract had particular inhibition behavior toward A. flauus and A. niger. Butylalcohol extract and aqueous extract had inhibitory effect toward bacteria, but no had inhibitory effect toward fungi. Petroleum ether extract had scarcely inhibitory effect toward bacteria and fungi. The maximal inhibition diameter was above 10mm, the minimum inhibition concentration was between 0.25%-3.0%. The extracts of E. ulmoides leaves had good thermostability on antimicrobial activities. Inhibition rate gradually increased with time, but hardly changed after 16h. Related Articles | Metrics

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Pollution Control on Industrialization of Gallotannin QIN Qing 2008, 28 (2):  73-76.  Abstract ( 622 )   PDF (848KB) ( 639 )   Save Pollution status of gallotannin industrialization in China was summarized. The characteristics of pollutants and key technologies of pollution control were discussed.The technique route of pollution control and implement policy were put forward. Related Articles | Metrics

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Preparation of a Novel Cellulose Adsorbent WANG Yu;WANG Dan;SHANG Shi-bin;SONG Zhan-qian;WANG Hong-xiao 2008, 28 (2):  77-81.  Abstract ( 652 )   PDF (884KB) ( 562 )   Save A novel cellulose adsorbent was made from bagasse cellulose, acrylic acid (AA), acrylamide(AM), and [2-(methyl-acryloyloxy)ethyl]trimethylammonium chloride (MAETAC) through graft copolymerization. Factors affecting the adsorption capacity of the product, such as NaOH mass fraction, alkalification time, AA dosage, neutralization degree of AA and AM dosage, were discussed in detail. The optimal conditions were found to be as follows: NaOH mass fraction 30%, alkalification time 90min, cellulose dosage 20%, neutralization degree of AA 60%, AA dosage 47.3%, AM dosage 26.3%, MAETAC dosage 6.4%, initiator dosage 2.6%, reaction temperature 70℃, reaction time 3h. Cu2+ adsorption of the adsorbent made under the optimized synthesis condition was 25.1mg/g. Related Articles | Metrics

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Research on the Scavenging Effect of Ethanol Extracts from Camellia oleifera Abel Leaves on 2,2-Diphenyl-1-picrylhydrazyl Radical LI Jiao-juan;HUANG Ke-ying;GONG Jian-liang;MA Wei 2008, 28 (2):  82-86.  Abstract ( 799 )   PDF (1087KB) ( 881 )   Save Antioxidant substances were extracted from Camellia oleifera Abel leaves with ethanol. Their antioxidant activities were determined and compared with rutin and BHT by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. EC50 values of DPPH radical scavenging were determined under wavelength of 517nm and reaction time of 40min. The results showed that ethanol extracts from C. oleifera leaves have significant effect on DPPH radical scavenging and the DPPH radical-scavenging efficiency increases with the purification degree of extracts from C. oleifera leaves. EC50 values of the crude extracts, purified extracts from C. oleifera leaves, rutin and BHT are 12.19, 6.765, 9.481 and 37.53mg/L, respectively. The sequence of radical scavenging ability is: purified extracts＞rutin＞crude extracts>>BHT. Related Articles | Metrics

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Isolation of Water-soluble Lignin-carbohydrate Complexes in Alkali Extractive of Wheat Straw by Hollow Fiber Ultrafiltration ZHU Chao-yu;ZHAI Hua-min 2008, 28 (2):  87-90.  Abstract ( 683 )   PDF (735KB) ( 502 )   Save The fraction of water-soluble lignin-carbohydrate complexes (LCC) containing sodium salt and low molecular weight (Mr) substances (<1000) was isolated from alkali extracting liquor of wheat straw by a solvent-extraction method. A hollow-fiber ultrafiltrator was used to isolate sodium salt and low Mr substances in the LCC. The results indicate that sodium salts and low Mr substances can be removed effectively after a total of ten times ultrafiltration loops with pressure 0.10MPa and concentration 0.5% were performed. The LCC fraction, which consists of 95.5% carbohydrate and 1.5% lignin, was obtained with high yield and purity. Related Articles | Metrics

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Preparation and Characterization of Tannin-chelated Resin through Inverse-suspension Polymerization ZHANG Li-ping;DU Jie 2008, 28 (2):  91-96.  Abstract ( 616 )   PDF (1350KB) ( 612 )   Save Using black wattle tannin and paraformaldehyde in fluid-wax as organic dispersant, a spherical tannin-chelated resin was prepared through inverse-suspension polymerization. The condition of reaction was determined by means of orthognonal experiment.The optimal condition of synthesis was: m(tannins):m(paraformaldehyde) 12:1, reaction temperature 67℃, reaction time 3.5h, fluid-wax volume 65mL. The structure of the product was characterized by Fourier transform IR, XRD, TG, DSC and SEM. The adsorption mechanism of tannin-chelated resin toward Cr6+ was investigated. Related Articles | Metrics

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Study on Oxidation of β-Pinene with Hydrogen Peroxide Catalyzed by Benzoic Acid Oxovanadium LI Jia-qi;GUO Dan;YIN Du-lin;XIAO Yi;MAO Li-qiu 2008, 28 (2):  97-100.  Abstract ( 623 )   PDF (785KB) ( 688 )   Save Oxidation of β-pinene with aqueous hydrogen peroxide as oxidant catalyzed by benzoic acid oxovanadium, which was synthesized by vanadium pentoxide, was successfully carried out under mild conditions. The effects of reaction conditions such as dosages of catalyst, H2O2, solvent and H2O on this reaction were investigated. The optimal reaction conditions were: V(acetone):V(β-pinene) 4:1, benzoic acid oxovanadium mass fraction 5%, n(H2O2):n(β-pinene) 2:1, reaction temperature 30℃.Reacting for 24 h under the optimal conditions, conversion of β-pinene can reach up to 56.2% and selectivities of major products nopinone and vebenone were 42.8% and 35.5% respectively. Related Articles | Metrics

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Study on Extraction and Purification of Flavonoids from Bamboo Leaves YUAN Ke;XUE Yue-qin;YE Su-ping;LOU Lu-huan 2008, 28 (2):  101-104.  Abstract ( 662 )   PDF (706KB) ( 876 )   Save Studies on the optimum process of extracting flavonoids from bamboo leaves were carried out by the method of orthogonal test, and flavonoids was determinated using rutin as reference substance. Bamboo leaves extracts were isolated and purificated by vacuum thin film concentration,ultrasonic decolorization, and adsorption with macroreticular resin Diaion HP-20. The result shows that the optimum process of extraction was 80%(volume fraction) ethanol, 10 times of the weight of raw material, extracting one time for 5min. The extracts were eluted on Diaion HP-20 resin column with a successive gradient elution system of H2O-MeOH at 5mL/min flow rate to obtain extract of flavonoids after vacuum concentration. The purity of flavonoids was 76%. Related Articles | Metrics

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Alcoholysis of Lignin with Ethylene Glycol FAN Yong-ming;XU Ai-qing;SHEN Yan-ni;LI Ming-fei;XIE Yi-min;ZHANG Zhi-yi 2008, 28 (2):  105-109.  Abstract ( 886 )   PDF (1089KB) ( 845 )   Save The alcoholysis of lignin through liquefaction with ethylene glycol was explored. The milled wood lignin (MWL) from Populus tomentosa Carr. was applied and the analysis of lignin structure alteration before and after alcoholysis was conducted with the aid of FT-IR and 1H NMR. It is showed in the results that lignin in P. tomentosa is of GS type, and G/S ratio 1.37. Alcoholysis of lignin caused the cleavage of most β-O-4 linkages and some methyl ether bonds, which lead to a great increase of phenolic structures in the lignin. The simple components obtained from lignin alcoholysis included phenolic ether, aromatic acids, aliphatic ether, unsaturated ketone and alcohols, etc. Condensation reaction was also observed during alcoholysis. Related Articles | Metrics

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Extraction and Analysis of Lipophilic Components from Brainia insignis(Hook.)J.Sm.by GC-MS FAN Ya-ming;FANG Xue-hui;LU Hui-ning;TAO Wen-qin;GAO Shao-zhong;CHEN Yong-heng 2008, 28 (2):  110-114.  Abstract ( 669 )   PDF (984KB) ( 708 )   Save The upstanding part of xylem caudex of Brainia insignis (Hook.) J. Sm. was extracted by organic solvents under low temperature and mild microwave irradiation. The extract was analyzed by GC-MS, 60 peaks were separated and 55 compounds were identified, which accounted for 97.88% of total peak area. The volatile components in B. insignis were classified into four structure groups: organic acids, sesquiterpenes, alkanes and cyclosiloxanes. From structural analysis, there are close correlations among individual groups of compounds. Especially in alkane and cyclosiloxane groups, there are similar structural differences between the neighboring compounds. The cyclosiloxanes have not been reported hitherto in fern research. Related Articles | Metrics

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Influences of Sampling Season and Storage Time on Yield and Chemical Composition of Essential Oil from Pine Needles WEN Fu-ji;YOO Kyung-seun 2008, 28 (2):  115-118.  Abstract ( 575 )   PDF (664KB) ( 627 )   Save Essential oil was extracted by hydro-distillation method from pine needles in different seasons with different storage time and then GC-MS analysis was carried out to determine chemical composition of the essential oil. The yield of pine-needle essential oil gathered in June was 0.61% and the major components of essential oil had the following order; α-pinene(19.00%), sabinene(19.61%), elemol(15.38%), bornyl acetate(10.05%). Total amount of terpenes in the sample of June exceeded 88.40%, which was the highest among the tested. After storages of 1, 3, 6, 12 months, oil yields of dry sample were 0.60%, 0.58%, 0.53% and 0.21%, respectively, while the amounts of terpenes in the essential oil were 79.93%, 76.03%, 74.33% and 64.97%, respectively. With the prolonging of storage time, the concentration of monoterpene in essential oil decreased, whereas the concentration of oxygenated terpene increased. Related Articles | Metrics

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Chemical Constituents from the Stems of Canthium simile Merr. & Chur. WANG An-wei;CHEN Guang-ying;YIN Wen-qing;HAN Chang-ri 2008, 28 (2):  124-126.  Abstract ( 763 )   PDF (563KB) ( 709 )   Save Chemical constituents of the stems of Canthium simile Merr. & Chur. were studied. Seven compounds were isolated from chloroform extract of the stem, and their structures were elucidated by various spectroscopic methods. They were identified as lupeol (Ⅰ), 3-β-acetyl oleanolic acid (Ⅱ), β-sitosterol(Ⅲ), 2,4-dihydroxy-3,6-dimethyl benzoate(Ⅳ), 2,6-dimethoxy-p-benzo quinine(Ⅴ), β-daucosterol(Ⅵ), vanillic acid(Ⅶ). All compounds were obtained from this genus of plant for the first time. Related Articles | Metrics