Table of Content

30 September 2005, Volume 25 Issue 3 Previous Issue    Next Issue

研究报告

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CHARACTERISTICS OF CELLULASE INDUCEMENT AND HYDROLYSIS BY RESIDUE OF XYLOOLIGOSACCHARIDE PRODUCTION YONG Qiang;FAN Yi-min;XU Yong;YU Shi-yuan 2005, 25 (3):  1-4.  Abstract ( 701 )   PDF (537KB) ( 778 )   Save The characteristics of cellulase inducement and hydrolysis by residue of xylooligosaccharide(XOS) production were investigated. The residue of XOS production was sensitive to cellulase,but it was a poor inducer for cellulase biosynthesis. The filter paper activity, volumetric productivity and yield by Trichoderma reesei,which employed residue of XOS production containing cellulose 15 g/L as carbon source,were 0.48 FPIU/mL, 6.67 FPIU/(L·h) and 32 FPIU/g cellulose,respectively. Compared to those of 3.20 FPIU/mL,19.00 FPIU/ (L·h) and 213.33 FPIU/g cellulose,which used untreated corncobs as carbon source. The enzymatic hydrolysis yield was 92.8% when 20 g/L residue of XOS production was treated with the dosage of 10 FPIU/g cellulases for 24h and when the substrate concentration was improved to 100 g/L,the hydrolysis yield was 80.6% for 48 h under the same conditions. Related Articles | Metrics

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STUDY ON PREPARATION OF GRANULAR ACTIVATED CARBON FOR n-BUTANE ADSORPTION JIANG Jian-chun;WANG Zhi-gao;DENG Xian-lun;CHANG Xia;ZHANG Yan-ping 2005, 25 (3):  5-8.  Abstract ( 702 )   PDF (554KB) ( 1572 )   Save Granular activated carbon for n-butane adsorption was prepared from sawdust by activation with phosphoric acid. The results showed that this prepared activated carbon had better properties than the imported one: n-butane working capacity (BWC)12.0 g/100 mL, abrasion resistance 96.95%. Effects of certain factors in preparing process, such as phosphoric acid concentration, mass ratio of phosphoric acid to sawdust,and drying technology on the properties were investigated. Through special treatment technologies during shaping and thereafter,all properties of granular activated carbon for n-butane adsorption were improved greatly. Besides,mechanism of the n-butane adsorption was also discussed to show that activated carbon with high percentage of pore volume within the range of 1.8-5 nm possesses high n-butane adsorbability. Related Articles | Metrics

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STUDIES OF GINKGO BILOBA L. POLYPRENOLS ON IMMUNOLOGICAL FUNCTION AND INDUCING APOPTOSIS OF TUMORS IN MOUSE WANG Cheng-zhang;SHEN Zhao-bang;LIU Yu-chan;GAO Ling 2005, 25 (3):  9-12.  Abstract ( 625 )   PDF (903KB) ( 767 )   Save Different dosages of polyprenols from Ginkgo biloba L. leaves(GP) were perfused to normal mouse and tumor mouse through stomach respectively. The phagocytic function of the macrophages were measured in the normal mouse by engulfing carbon granula ability. Apoptosis (APO), S phase fraction (SPF), proliferation index(PI) and CD4/CD8 rate of T lymphocytes were investigated by flow cytometry (FCM) in mouse with S180 tumor. The results showed that polyprenols of G. biloba L. at 10 and 20 mg/kg could increase remarkably the phagocytic function which was higher than the clearance of cyclophosphamide (CTX). In comparison with the control group, the high GP group (40 mg/kg) could increase the index of the thymus gland in mouse with heps and index of the spleen in mouse with EC. The APO level in mouse with S180 tumor in 5 mg/kg GP was 6.35,which went up significantly compared to the control group and other administration groups, and made the rate of CD4/CD8 near to that of the normal mouse. Related Articles | Metrics

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A NOVEL PHENOLIC COMPOUND FROM LEAVES OF ILEX PURPUREA HASSK. LIAO Li-ping;BI Zhi-ming;LI Ping;ZHANG Ti-deng 2005, 25 (3):  13-15.  Abstract ( 617 )   PDF (696KB) ( 640 )   Save To study the constituents in leaves of Ilex purpreae Hassk., which are used as one kind of traditional Chinese medicine, 10 kg dried leaves were extracted with 80% EtOH (8 times of the materials ) for 3 times,each time for 4 h. The filtrate was concentrated in vaccum to remove ethanol completely.The residue was suspended in water,extracted successively with petroleum ether, ethyl acetate and n-BuOH. The n-BuOH fraction was subjected to different column chromatography for isolation and purification. A phenolic compound was isolated. Its structure, elucidated by chemical and spectral methods,was 3,4-dihydroxy-7-(3′-O-β-D-glucopyranosyl-4′-hydroxy-benzoyl)-benzylalcohol,which is a novel natural product. Related Articles | Metrics

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STUDY ON REACTIVITY OF CHARS FROM BIOMASS PYROLYSIS LU Chun-lan;XU Shao-ping;DENG Xiao-long;LIU Shu-qin;LIU Chang-hou 2005, 25 (3):  16-20.  Abstract ( 650 )   PDF (775KB) ( 1204 )   Save A new method was developed for measuring the reactivity of char from biomass pyrolysis. The reactivities of chars from rapid pyrolysis in a free-fall reactor and slow pyrolysis in a steel jar were studied at 800℃. Similar experiments were carried out with charcoal, petroleum coke and metallurgic coke for comparative study. The relationship between reactivity and surface area of the char was also investigated. Results showed that the new method is simple and works well. The reactivities of the char from biomass pyrolysis are a little lower than that of charcoal, but mostly higher than those of petroleum coke and metallurgic coke. The chars are suitable for gasification and combustion. Surface area of the chars increase slightly with the increase of pyrolysis temperature. Both characteristics of raw material and heating rate affect the reactivity and surface area of the char. Related Articles | Metrics

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STUDY ON CHEMICAL CONSTITUENTS OF POLYGONUM HYDROPIPER LINN. ZHANG Guo-ying;ZENG Tao 2005, 25 (3):  21-24.  Abstract ( 736 )   PDF (896KB) ( 875 )   Save Five flavonoid compounds were isolated from Polygonum hydropiper Linn. by polyamide chromatography and their structures were determined as follows: hyperin, rutin, quercetin, isorhamnetin and kaempferol. Isorhamnetin was first obtained from this plant. Volatile oil in leaves of P. hydropiper Linn. was extracted by supercritical carbon dioxide, and their chemical constituents were separated and identified by GC-MS. The amount of identified constituents was over 80.66% of the volatile oil. Related Articles | Metrics

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STUDY ON DECOLORIZATION AND IMPURITY-ELIMINATION OF EXTRACTS OF RABDOSIA REBESCENS YUAN Ke;YANG Zhong-han 2005, 25 (3):  25-28.  Abstract ( 557 )   PDF (582KB) ( 694 )   Save In the process of large-scale extracting research of oridonin, a large amount of components of pigment and fat were also extracted as impurities. A systematic research on method of decolorization and impurity-elimination was carried out, by adopting 5 methods respectively for comparison, namely: adsorption with big-bore resin, extraction with petroleum ether, extraction with ethanol and sedimentation with water, refluxing with activated carbon, ultrasonic treatment with activated carbon. The best method was determined as ultractionic treatment with activated carbon. Through orthogonal test, the optimum condition was: twice ultrasonic treatments with 5% of activated carbon, ultrasonic treatment for 20 min each time. Related Articles | Metrics

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STUDY ON ANTI-MICROBIAL FUNCTIONS OF BAMBOO-VINEGAR DISTILLATES ZOU Xiao-ming;QIANG Jun-qing;LU Shi-yong 2005, 25 (3):  33-37.  Abstract ( 616 )   PDF (825KB) ( 761 )   Save In order to explore anti-microbial capability of different components in bamboo-vinegar liquor, distillates of bamboo-vinegar liquor were separated by vacuum distillation. Anti-microbial experiments were carried out respectively with Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Saccharomyces cerevisiae, Aspergillus niger to measure anti-microbial capability, compared with bamboo-vinegar liquor. The results showed that only one distillate has anti-bacterial and anti-fungal actions comparable to bamboo vinegar liquor. Under the conditions of distillation temperature 70℃, vacuum 0.1 MPa, distillate volume 25%(volume part), distillate pH value 6.0, the distillate has the best anti-microbial functions,which are superior to those of bamboo-vinegar liquor. Related Articles | Metrics

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CHEMICAL CONSTITUENTS IN FLOWER BUDS OF LONICERA JAPONICA THUNB. LI Hui-Jun;LI Ping 2005, 25 (3):  29-32.  Abstract ( 705 )   PDF (892KB) ( 842 )   Save Active constituents were isolated from the flower buds of Lonicera japonica Thunb. They were extracted with 70% alcohol, then fractioned successively with petroleum ether, ethyl acetate and n-butanol. The ethyl acetate part was repeatedly chromatographed on silica gel column and purified with ODS column. Nine compounds, namely loganin(1),sweroside(2),7-epi-vogeloside(3),7-epi-loganin(4),secoxyloganin(5),caffeic acid(6),p-hydroxybenzoic acid(7), β-sitosterol(8) and daucosterol (9) were obtained and their structures were deduced by comparison of their physico-chemical properties and spectral data with those of reference data. Compounds 4,5,6,7 were found for the first time in the flower buds of L. japonica Thunb., and compounds 1,4,5 were found to possess hepato- protective effect. Related Articles | Metrics

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STUDY ON ADSORPTION AND PHOTOCATALYTIC DECOMPOSITION OF FORMALDEHYDE WITH TiO2-ACTIVATED CARBON COMPOSITES HUANG Biao;CHEN Xue-rong;JIANG Mao-sheng;TANG Xing-ping;LIAO Yi-qiang;YANG Qing-xian 2005, 25 (3):  38-42.  Abstract ( 680 )   PDF (915KB) ( 951 )   Save An effort was made to develop a photocatalytic TiO2-activated carbon composite from tetraisopropyl titanate-soaked activated carbon in supercritical ethanol. The structure of the composite was characterized,its effect on photocatalytic decomposition of formaldehyde was also evaluated. Results showed that the supercritically treated TiO2-activated carbon (Sc-TiO2-AC)composite had a much higher decomposing ability than that of the simple physical mixture of activated carbon and TiO2 granules. Moreover,the photocatalytic composite possesses high synergistic effect on adsorption and photocatalytic decomposition of formaldehyde, so that photocatalytic decomposition rate can be accelerated and the in-situ regeneration of the adsorbent can be achieved. Results show that at temperature of supercritical treatment 300℃, formaldehyde-removal rate of the composite is the highest. The formaldehyde-removal rates of the composites prepared by supercritical treatment at 300,350,400℃ are 100%,96%,93%, respectively. Related Articles | Metrics

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STUDY ON SYNTHESIS OF EPOXY RESIN FROM MIXTURE OF ACRYPIMARIC ACID AND C-36 DIMERIC FATTY ACID XIA Jian-ling;LI Heng;NIE Xiao-an;WANG Ding-xuan 2005, 25 (3):  43-46.  Abstract ( 643 )   PDF (812KB) ( 725 )   Save Gum rosin is a natural forest chemical resourses in China containing abundant constituents of abietic-type resin acids. Acrylpimaric acid (APA) was made by abietic-type resin acids and acrylic acid. In this paper, a complex epoxy resin was synthesized by esterification and ring-closure of acrylpimaric acid and C-36 dimeric acid(DA) with excessive epichlohydrin(ECH). The influences of reaction parameters were discussed respectively, such as esterification time and temperature, catalyst dosage, ring-closing temperature, dosages of ECH, NaOH, etc. The complex epoxy resin synthesized under suitable condition had the following properties: epoxy value 0.26 eq per 100 g, viscosity at 40℃ 1 220 mPa·s, acid value 0.3 mg/g. FT-IR spectra of the raw material and the product were also compared. Related Articles | Metrics

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FUNCTION OF IRON-BASED CATALYST IN THE LIQUEFACTION OF BAGASSE GUO Gui-quan;WEI Wen;WANG Hong-juan;CHEN Fan-geng 2005, 25 (3):  47-50.  Abstract ( 566 )   PDF (648KB) ( 710 )   Save The liquefaction of bagasse was conducted in tetralin. The liquefaction behaviors in the presence of iron-based catalyst and without any catalyst were compared. The yield of hydrogen from liquefaction was enhanced with iron-based catalyst and the residue content was reduced simultaneously. The results suggest that the catalyst favors the formation of oil. At 400℃, oil yield of liquefaction with iron-based catalyst was higher than that without catalyst, average relative molecular weight (Mw) of liquid product produced with iron-based catalyst was lower than that without catalyst. At 500℃, the use of iron-based catalyst did not significantly enhance oil yield, but increased Mw of the liquid products. The results imply that the catalyst has different influences on Mw of liquid products and gas yield at different temperatures. It also indicates that iron-based catalyst can promote the transformation of hydrogen from tetralin to the degradated fragments. Related Articles | Metrics

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ENHANCEMENT OF TAXANES PRODUCTION IN CELL SUSPENSION CULTURES OF TAXUS CHINENSIS BY PRECURSOR-FEEDING ZHOU Zhong-qiang;MEI Xing-guo 2005, 25 (3):  51-54.  Abstract ( 608 )   PDF (584KB) ( 645 )   Save The effects of precursors on taxanes production in cell suspension cultures of Taxus chinensis(Pilg.)Rehd. were studied. Feeding of sodium pyruvate at 0.5 mmol/L enhanced the yields of taxol and 1β-hydroxy baccatin Ⅰat 336% and 325.8% of control, respectively. Taxuyunnanine C yield was greatly promoted in presence of 3-methyl-2-buten-1-ol at 2 mmol/L (318.6% of control) and sodium benzoate at 0.4 mmol/L ( 345.2% of control). Yield increase of 14β-(2-methyl-butyryl)oxo-2α,5α,10β-triacetoxytaxa-4(20), 11-diene was most pronounced in presence of sodium acetate (293% of control at 1 mmol/L) and sodium pyruvate (310.4% of control at 0.5 mmol/L). The results showed that precursor-feeding at optimal concentration is advantageous to biosynthesis of taxanes. Related Articles | Metrics

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STUDY ON EXTRACTION OF ESSENTIAL OIL FROM DIOSOPYROSI KAKI LEAVES BY SUPERCRITICAL CARBON DIOXIDE YUE Hong;ZHANG Ying;ZHAO Xiao-li;LI Xiao-yin 2005, 25 (3):  55-58.  Abstract ( 623 )   PDF (516KB) ( 607 )   Save Factors in the supercritical fluid extraction of Diospyros kaki leaves through single factor test and orthogonal test were studied. The flow chart was optimized. The results showed that the effects of factors in the decreased order are: pressure, temperature, CO2 flow rate and time. The best extraction condition could be obtained: 100 g D. kaki leaves at pressure 18 MPa, temperature 50℃, CO2 flow rate 20 kg/h and time 2.5 h,extraction yield 3.1%. The yield of essential oil by supercritical CO2 extraction(SCDE) was increased 55% than steam distillation. The oil is a light yellow liquid with high purity and strong flavoring of D. kaki fruit. Related Articles | Metrics

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THE PRESSURIED/TEMPERATURE HYDROGEN PEROXIDE BLEACHING OF WHEAT-STRAW SODA-OXYGEN PULPS CAO Yun-feng;YANG Yi-qin;LI Zhong-zheng 2005, 25 (3):  59-62.  Abstract ( 648 )   PDF (563KB) ( 918 )   Save Wheat-straw soda/soda-oxygen pulps were bleached through pressurized-temperature H2O2(P pt) in this research. Kappa number of pulp decreased with increasing of H2O2 charge and oxygen pressure. Kappa number was reduced from 17.3 to 2.38, the removal of remaining lignin up to 86.2%. That is to say that Ppt bleaching had high efficiency of delignification. Brightnesses of the bleached wheat straw soda-oxygen pulps by both-oxygen delignification-chelant pretreatment-pressurized/temperature H2O2(OQPpt) and oxygen delignification-acidic pretreatment- pressurized/temperature H2O2(OAPpt) sequences reached to about 80% (SBD), when 3%-4% peroxide charge as used in the Ppt bleaching stage, while brightness of the pulp bleached by sequence of OAPpt was 2.0% (SBD) higher than that by the OQPpt sequence and the degree of polymerization of bleached pulp reached about 1 038. Related Articles | Metrics

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DETERMINATION OF CAMPTOTHECIN AND 10-HYDROXYCAMPTOTHECIN IN CAMPTOTHECA ACUMINATA D. SEEDS BY HPLC WANG Yang;YAN Xiu-feng;ZHANG Yu-hong;YU Tao;MA Mei-fang;WEI Huan-yong 2005, 25 (3):  63-66.  Abstract ( 541 )   PDF (519KB) ( 642 )   Save A simple, rapid and sensitive method for the determination of contents of camptothecin (CPT) and 10-hydroxycamptothecin (HCPT) in Camptotheca acuminata Decne. seeds by HPLC was established. The HPLC separation was performed on a KYA HIQ sil C18 column (250 mm×4.6 mm, 5 μm) at flow rate 1 mL/min, the solvent gradient program was as follow: acetonitrile-water increased linearly from 10% to 40% in the first 15 min, then decreased linearly to 10% in 3 min; at time 21 min, stopped the program. The alkaloids were detected by a photodiode array detector and quantitatively analyzed at 254 nm for CPT and 266 nm for HCPT. CPT and HCPT were ultrasonically extracted by 60% alcohol at 60℃ for 50 min. CPT and HCPT contents in different parts of C. acuminata D. seeds were determined by the above analyzing method. The results showed that CPT and HCPT levels were different in the four parts of C. acuminata D. seeds. CPT content was the highest in endosperm, lower in embryonic axis and cotyledon, and the lowest in seed coat, whereas HCPT content was the highest in endosperm, lower in seed coat, and the lowest in embryonic axis and cotyledon. Related Articles | Metrics

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RESEARCH ON TECHNOLOGY TO PREPARE ACTIVATED CARBON FROM SHELL OF SUNFLOWER SEED BY THE MICROWAVE METHOD GAO Hui;ZHOU Xue-hui 2005, 25 (3):  67-70.  Abstract ( 699 )   PDF (877KB) ( 663 )   Save Activated carbons from the shell of sunflower seed have different qualities by the preparation methods of steam activation, phosphoric acid-spinning stove and phosphoric acid-microwave. Results showed that the properties of activated carbon by phosphoric acid-micvowave method are superior. Influencing factors on properties of activated carbon such as phosphoric acid concentration, activation time and catalyst were systematically studied by means of orthogonal test under microwave irradiation of 700 W. The optimum condition for decolorization capacity of methylene blue was obtained as follows: phosphoric acid concentration 30°Be′, activation time 25 min, catalyst No.1 4%, catalyst No.22%. The optimum condition for iodine number was obtained as follows: phosphoric acid concentration 35°Be′, activation time 25 min, catalyst No.1 4%, catalyst No.22%. The optimum condition for decolorization capacity of caramel adsorption was obtained as follows: phosphoric acid concentration 30°Be′, activation time 35 min, catalyst No.12%, catalyst No.22%. Related Articles | Metrics

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INFLUENCE OF PURIFICATION METHOD ON THE STRUCTURE AND PROPERTIES OF KONJAC GLUCOMANNAN LIU Ting-guo;WANG Yang;XIA Jun;LI Bin 2005, 25 (3):  71-75.  Abstract ( 699 )   PDF (846KB) ( 1081 )   Save Konjac glaucomannan (KGM) was purified by ethanol, Pb(Ac)2 and H2O2 respectively. The content analysis showed that high purity KGM could be obtained by ethanol or Pb(Ac)2 method, but not by H2O2 method. Treatment under mild condition with solvent of lower polarity was in favor of keeping the molecular structure and properties such as water-solubility, gelatination, etc. Acetyl groups were partially eliminated when purified by Pb(Ac)2 method, leading to increased crystallinity and glass temperature, which resulted in losts of water-solubility and gelatinability. Owing to the slight oxidative degradation with H2O2 method, the changes of chain size and some functional groups of KGM molecule led to decrease of viscosity and excessive swelling rate. In a word, the purification method has great influence on the structure and properties of KGM, so that selection of optimal purification method was the precondition to evaluate the properties and bioactivity of KGM. Related Articles | Metrics

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ADSORPTION AND RECYCLING OF CELLULASE DURING HYDROLYSIS OF CORNCOB ZHAN Xiao-ming;XIA Li-ming 2005, 25 (3):  76-80.  Abstract ( 681 )   PDF (780KB) ( 830 )   Save The adsorption and functions of hydrolysis of cellulase on corncob substrate were studied. The adsorption characteristics of three cellulase components were different during hydrolysis. Factors affecting cellulase adsorption were investigated, including granularity of corncob, pretreatment conditions, pH value and temperature. Under standard hydrolysis conditions of cellulosic substrate(corncob 10%, pH value 4.8, 50℃),endo-β-1,4-glucanase(CMCase) and exo-β-1,4-glucanase(C1) were mainly absorbed on the substrate, but cellobiase (CB) was mostly maintained in the liquid phase. A process for recycling enzyme during cellulose hydrolysis was set up based on the adsorption characters of cellulase. Under batch hydrolysis process the substrate mass part 10% and initial cellulase dosage 15 FPIU/g substrate, the hydrolyzate was removed while the cellulosic residue adsorbing cellulase was remained after 48 h reaction. Then the fresh substrate was added into the reaction system with cellobiase(4 IU/g substrate) and partial cellulase (7.5 FPIU/g substrate). The process was repeated for 7 batches and average hydrolysis yield of corncob was over 80% with the saving of 50% cellulase. The results of this research were meaningful in the enzymatic saccharification of renewable cellulosic resources. Related Articles | Metrics

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STUDY ON EXTRACTION OF CHLOROPHYLL FROM LEAVES OF INDOCALAMUS HERKLOTSII M. WITH SUPERCRITICAL CARBON DIOXIDE LUO Jin-yue;CHEN Fang;ZHU Chun-lei;AN Xin-nan 2005, 25 (3):  81-84.  Abstract ( 573 )   PDF (593KB) ( 666 )   Save The extraction and isolation conditions of chlorophyll were studied using the leaves of Indocalamus herklotsii McClure with supercritical CO2 extraction (SCDE). Influences of extraction temperature, pressure, and time on the content and purity of chlorophyll were investigated, and suitable conditions were determined based on single- factor tests as follows: extraction temperature 50℃, extraction pressure 25 MPa, 95% alcohol (volume part) as a modifier was used at dosage of 8 mL per gram material, extraction for 4 times. The yield of chlorophyll was 0.45% under the above conditions. A new method for isolating chlorophyll from leaves of I. herklotsii was provided in this research. Related Articles | Metrics

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AN ORTHOGONAL EXPERIMENT TO OPTIMIZE ULTRASONIC EXTRACTION OF FLAVONOIDS IN HIPPOPHAE RHAMNOIDES L. ZU Yuan-gang;ZHAO Chun-jian;FU Yu-jie;LI Chun-ying;YANG Lei;WANG Yan-bing 2005, 25 (3):  85-88.  Abstract ( 656 )   PDF (723KB) ( 881 )   Save Ultrasonic extraction of flavonoids in leaves of Hippophae rhamnoides Linn. (TFH) was optimized by an orthogonal experiment. The effects of ultrasonic treatment time, temperature, ratio of liquor to material and extraction times on the extraction yield of TFH were investigated. The optimized ultrasonic extraction was determined as follows: ratio of liquor to material 25 mL/g at 46℃ for 25 min with 85% ethanol in a single ultrasonic extraction process. A comparison was conducted between ultrasonic and Soxhlet extraction. The extraction yield of TFH is 1.72% by ultrasonic extraction, which is almost the same as by Soxhlet extraction. Ultrasonic extraction is faster and needs less solvent, which are superior to Soxhlet extraction. Mathematical simulation values based on ultrasonic extraction are consistent with experimental values. Related Articles | Metrics

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STUDY ON PREPARATION AND CHARACTERISTICS OF SUDIUM-IRON-CHLOROPHYLLIN FROM BAMBOO LEAVES WANG Li-juan;QIAN Xue-ren 2005, 25 (3):  89-92.  Abstract ( 639 )   PDF (665KB) ( 869 )   Save Natural water-soluble green pigment named sodium-iron-chlorophyllin was prepared from bamboo leaves which is a kind of waste in bamboo processing. Two key preparation processes——saponification and iron substitution reaction and the stability of the pigment were investigated. It was found that optimum conditions of saponification were sodium hydroxide 5% and temperature 70℃ for 60 min. At pH value 3.0, temperature of water bath 60℃ for 60 min, a high proportion of sodium-iron-chlorophyllin was obtained. The pH value in the range of 3.0-6.0 had no effect on stability of sodium-iron-chlorophyllin obtained and it was stable against heat, room light and reducing agent. The results showed that sodium-iron-chlorophyllin from bamboo leaves is a kind of excellent natural edible green pigment. Related Articles | Metrics

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STUDY ON CHEMICAL REGENERATING METHOD OF GRANULAR ACTIVATED CARBON FOR CITRIC ACID INDUSTRY SUN Kang;JIANG Jian-chun;DENG Xian-lun;DAI Wei-di;LIU Han-chao 2005, 25 (3):  93-96.  Abstract ( 649 )   PDF (502KB) ( 990 )   Save The regenerating method of granular activated carbon (GAC) capable of caramel decoloration used for decolorizing and refining citric acid solution was investigated. In experiments, improved means were adopted to advance the traditional regenerating method.During regeneration with NaOH,addition of a little amount of oxidizing agent and surface active agent can increase adsorption capacity of regenerated activated carbon over 10%. The dosage of oxidizing agent is 3% of GAC; that of surface active agent is 0.1%. This investigation offers an economical method for regenerating GAC used for decolorizing and refining products for citric acid industry. Related Articles | Metrics

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STUDY ON MICROWAVE ASSISTED EXTRACTION OF EMODIN CHENG Cun-gui;LI Dan-ting;CHEN Bing-chu 2005, 25 (3):  97-99.  Abstract ( 648 )   PDF (502KB) ( 687 )   Save Microwave assisted extraction (MAE) was used to extract emod in from Polygonum cuspidatum Sieb. et Zucc. The orthogonal test design was used to optmiize the effects of microwave power, particle size and extractiontmie on the extraction yield of emodin. Parallel tests were carried out including the optimal process, water extractionm ethod and ethanol refluxing method. The results showed that particle size of P. cuspidatum and microwave power are the significant factors with P< 0.01 and P< 0.05, respectively and time is an affective factor on the extraction of emod in( 0.05 < P < 0.1). Microwave assisted extraction method is superior to water extraction and ethanol refluxing method. With 70% a lcohol aqueous so lution, microwave power 480W for 20min, the yield of extraction of MAE was 1.63%. Related Articles | Metrics

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NMR STUDY OF ENDO-ISOCAMPHANYL METHANOL AND ITS DERIVATIVES DING Qiu-ping;PENG Yi-yuan;XIAO Zhuan-quan 2005, 25 (3):  100-102.  Abstract ( 500 )   PDF (487KB) ( 570 )   Save The structures of 6 endo-isocamphanyl methanol and its derivatives were determined by 1D NMR spectroscopy (1H NMR,13C NMR,DEPT) and 2D NMR spectroscopy (1H-1H COSY,HSQC,HMBC,1H-1H NOESY). All 1H NMR and 13C NMR data were assigned, and the influences on chemical shifts from the substituted groups were discussed. The NMR data of these compounds can be used as the reference for these series of compounds. Related Articles | Metrics

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SYNTHESES AND APPLICATION OF PHENOL-FORMALDEHYDE RESIN MODIFIED WITH AMINES TIAN Zhong-jian;QIU Hua-yu;ZHANG Xue-jin;JI Xing-xiang 2005, 25 (3):  103-106.  Abstract ( 602 )   PDF (612KB) ( 541 )   Save Syntheses of phenol-formaldehyde resin (PFR)modified with dimethylamine and isopropylamine respectively under suitable conditions were investigated. Cationic phenol-formaldehyde resins(CPFR)and polyethylene oxide(PEO)comprised a binary retention system which was used for deinked pulp of waste paper. The results showed that the retention system could improve the retention of micro-fibers and fillers remarkably, and the first pulp retention could be achieved more than 90%. Effects on the retention system composed of PEO and CPFR were affected by dosages of retention aids, ratio of PEO-CPFR, pH value of pulp and shearing stress, etc. The optimal conditions of the system were as follows: dosage of PEO 0.02%-0.04%, ratio of PEO-CPFR 1:6-1:12, pH value 4-9. The system can endure shearing stress of rotor at 400-1000 r/min. Related Articles | Metrics

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REGIOSELECTIVE SULFATION FOR MODIFICATION OF MICROCRYSTALLINE CELLULOSE AND ITS STRUCTURAL CHARACTERIZATION WANG Zhao-mei;LI Lin;HU Song-qing;XIAO Lei 2005, 25 (3):  107-110.  Abstract ( 608 )   PDF (578KB) ( 829 )   Save In order to establish a chemical stock of cellulose sulfate analogues having different substitution patterns for investigating structure-efficacy relationship, a method for regioselective sulfation of microcrystalline cellulose (MCC) was described to control the position and distribution of sulfate groups in cellulose sulfates. The bulky protective group (CH3)3COC— was introduced at C-6-hydroxyl group by selective pivaloylation of MCC. Sulfation of the C-6 -substituted intermediate followed by depivaloylation give two cellulose sulfates, coded as Na-MCS1 and Na-MCS1. The structures of the intermediates and the aimed products were confirmed by IR, UV and 13C NMR spectra. The substitution patterns disclosed by quantitative 13C NMR showed that Na-MCS1 had sulfate groups both at C-6 and C-2, and Na-MCS2 only at C-2. Related Articles | Metrics

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STUDY ON PREPARATION OF ULTRAFINE CAPSULES WITH CHITOSAN BY MONOPHASIC COAGULATION LIU Wen-bo;SONG Zhan-qian;YU Gang 2005, 25 (3):  115-119.  Abstract ( 638 )   PDF (1103KB) ( 869 )   Save In this article, the mechanism and general process of preparing capsule by monophasic coagulation were investigated, and capsules were prepared from natural macromolecule material chitosan as wall material and vitamin E as core material by monophasic coagulation. The optimum conditions were that core-wall ratio 1:1,emulsifying time 30 min, emulsifying stirring rate 7 500-9000 r/min,emulsifier MMAS dosage 6.0%,hardener dose was twice of that of wall material and hardenig time was 60 min at low temperature. The surface feature of the capsules was spheric and phase verge was obvious.The particle size was 0.10-3.00 μm. The particles obtained were uniform and their size distribution fluctuated in a small range, possessing high heat-resistance, stability and good dispersibility. Related Articles | Metrics

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STUDIES ON ENZYMIC EXTRACTION OF ESSENTIAL OIL FROM PINE NEEDLES LIU Xiao-geng;JU Xing-rong;MAO Xu-dong;ZHANG Zhen 2005, 25 (3):  111-114.  Abstract ( 803 )   PDF (723KB) ( 924 )   Save Five methods of extracting essential oil (natural perfume) from fresh pine needles have been compared, namely: enzymic (EZ), microwave-assisted (MA), steam distillation (SD), microwave-assisted enzymic (MAEZ), and microwave-assisted ionic liquid enzymic (MAILEZ) methods. The results showed that essential oil yield from MAEZ method was 0.493%-0.530%, 12.3% higher than that of single enzymolysis. The optimum conditions of EZ method were obtained by experiment as follows: moisture 10%-13%, temperature (50±5)℃, pH value 4.0-5.5, mass ratio of enzyme to pine needles 1:500, mass ratio of imidazole ionic liquid to pine needles 4.0-5.5:1, enzymolysis time 60-90 min, microwave irradiation time 10-14 min. The recovery rate of ionic liquid was 98.5%-100%. Related Articles | Metrics

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ADVANCES IN STUDIES ON ANTIOXIDATIVE ACTIVITY AND CARDIO-CEREBROVASCULAR PHARMACOLOGY OF BAMBOO-LEAF-FLAVONOIDS LU Bai-yi;ZHANG Ying;WU Xiao-qin 2005, 25 (3):  120-124.  Abstract ( 755 )   PDF (604KB) ( 1302 )   Save The advances in researches on antioxidative activities and pharmacologic activities of bamboo-leaf- flavonoids (EOB-f) against cardio-cerebrovascular diseases were reviewed. 1) Experiments in vitro and vivo showed that EOB-f could scavenge radicals, prevent lipid peroxidation and increase the level of antioxidation in vivo; 2) Animal tests and clinic tests showed that EOB-f could significantly depress the triglyceride level and elevate the high density lipoprotein cholesterol level in serum of animal and human; 3) Pharmacological experiments revealed that EOB-f could efficiently expand coronary artery and increase its flux, improve the blood supply of heart muscle and shrink the area of myocardial infarction, decrease the congregation of blood platelet and inhibit thrombosis, and keep brain tissue from blood shortage. In short words, EOB-f may be a kind of promising natural products for the development of medicine and dietary supplement against cardio-cerebrovascular diseases. Related Articles | Metrics

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ADVANCES IN STUDIES ON MECHANISM OF CELLULOSE DEGRADATION BY ENZYMIC HYDROLYSIS AND OXIDATION WANG Xi-guo;YANG Qian;YAN Hong 2005, 25 (3):  125-130.  Abstract ( 851 )   PDF (756KB) ( 1986 )   Save The development and application of cellulose is limited because the mechanism of cellulose bio-degradation has not yet been clearly understood. Since hypothesis of C1—Cx was suggested, other theories of degradation were suggested to modify the former. It is obvious that enzymic hydrolysis mechanism of cellulose alone could not explain degradation of natural cellulose completely. In this article, representative enzymatic synergisms, hypothesis of cellobiohydrolase(CBH) synergism, HO· radical oxidation and cellobioes dehydrogenase have been mainly introduced. The pathway of cellulose degradation could be better understood through combination of hydrolysis mechanism and oxidation mechanism. Related Articles | Metrics