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Table of Content

    28 February 2010, Volume 30 Issue 1 Previous Issue    Next Issue
    研究报告
    Synthesis of γ-Valerolactone from Biomass-based Levulinic Acid over Ru/C Catalyst
    YAN Zhi-pei;LIN Lu
    2010, 30 (1):  11-16. 
    Abstract ( 478 )   PDF (1107KB) ( 855 )   Save
    Ru/C, a ctalyst of high-activity, was used in the experiments of hydrogenation of levulinic acid, and the variations of the fresh and used catalysts were characterized by XRD and XPS. The reaction pathway for the hydrogenation of levulinic acid was proposed. The suitable conditions of preparing γ-valerolactone(GVL) by hydrogenation of levulinic acid catalyzed by Ru/C were as follows:temperature 130℃, pressure 1.2MPa, dosage of catalyst 5.0%(based on the mass fraction of levulinic acid) and solvent was absolute methanol. The conversion rate of levulinic acid was 92%, and the selectivity of γ-valerolactone was 99%. The conversion rate of raw material and the selectivity of γ-valerolactone with Ru/C as catalyst were higher than those of Pd/C,Raney nickel and Urushibara nickel.
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    Study on Composition of Phytoncidere from Lavandula angustifolia Mill. at Room Temperature
    XU Jie-hua;KONG Hui;WEN Shou-wen;WU Da-peng
    2010, 30 (1):  81-84. 
    Abstract ( 688 )   PDF (879KB) ( 623 )   Save
    Chemical composition and content of phytoncidere from Lavandula angustifolia Mill. were studied. Phytoncidere was collected by filter flask and air sampler, and analyzed by GC-MS with peak area normalization method. Thirteen chemical compositions were found at room temperature, mainly p-isopropyl toluene(23.17%), limonene(20.76%), 1-methyl-4-(1-methylethenyl)benzene(17.58%). The results showed significant difference in chemical composition between essential oil and phytoncidere.
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    Optimization of Technology Using Response Surface Analysis for Extracting Flavonoids from Seabuckthorn Residue Assisted by Cellulase
    JIAO Yan;WANG Zhen-yu;
    2010, 30 (1):  85-91. 
    Abstract ( 672 )   PDF (1260KB) ( 745 )   Save
    Flavonoids were extracted from seabuckthorn (Hippophae rhamnoides Linn.)residue by cellulase-assisted technique. The extracting condition was optimized using response surface analysis based on single factor experiments. A mathematical model was established and analyzed by response surface methodology(RSM) to describe the relationships among mass ratio of cellulase,ratio of solutions to material,extraction temperature,pH value and extraction yield of flavonoids. The optimal flavonoids extraction conditions were:dosage of cellulase 78.9IU/g,ratio of solutions to material 25.9,temperature 59.1℃ and pH value 3.9.Under the optimized extraction conditions, flavonoids yield is (8.48±0.16)mg/g(n=3),which is close to the estimated value 8.57mg/g attained from regression model.This model can be used to predict the experiment results well.
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    综述评论
    Recent Advances in Researches of Purple Corn Anthocyanins
    JING Pu;ZHANG Xiao-guang;DONG Ying
    2010, 30 (1):  103-110. 
    Abstract ( 618 )   PDF (1418KB) ( 944 )   Save
    Anthocyanins from purple corn (Zea mays L.) are not only safe as a natural food colorant but also rich in health benefits. Based on the researches of authors for years in USA on anthocyanins and other international scientists' recent achievements, recent advance in researches of purple corn anthocyanins were reviewed, including anthocyanin contents and structures of purple corn, biological effects, relationship between structures and functions, effects of structural modification and processing on their biological activities, extraction and comprehensive utilization. The future research direction and development trend of purple corn anthocyanins were also suggested for consideration.
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    研究报告
    Determination on Physical Features of Tara Beans and Review of Its Current Researches
    ZHANG Jian-yun;BAO Song-lian;LI Zhi-guo;LUO Xiang;YANG Shi-yu
    2010, 30 (1):  116-122. 
    Abstract ( 654 )   PDF (1401KB) ( 820 )   Save
    The grading guideline of tara beans was put forward by determining physical features of tara beans to obtain the result as follows:length of tara(Caesalpinia spinosa Kuntze) beans was 0.620-1.184cm with average 0.899cm, thickness of tara beans was 0.149-0.678cm with average 0.426cm, mass of thousand grains of tara beans was 146-245g with average 195.02g. Tara bean is consisted of bean shell 34.0%- 42.0% with average 39.0%, bean embryo 24.0%-34.0% with average 31.0% and bean endosperm 21.0%-31.0% with average 26.0%. The constitution, chemical constituents, processing and characterstics of tara beans in China,as well as current states of researches and development trend of tara beans are briefly decribed.
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    Optimization of Microwave-assisted Extraction of Jujuboside A from Zizyphus jujuba Seeds
    FANG Xin-sheng;WANG Jian-hua;ZHU Li-xiang;ZHOU Hong-ying;LIU Er-gang;YANG Ling-ying
    2010, 30 (1):  92-96. 
    Abstract ( 680 )   PDF (1134KB) ( 776 )   Save
    To optimize the key parameters of microwave-assisted extraction(MAE) of jujuboside A from seeds of Zizyphus jujuba Mill.var.spinosa(Bunge.)Hu ex H.F.Chou., the effects of volume fraction of ethanol, microwave extraction time, temperature, microwave power, and liquid to solid ratio on the yield of jujuboside A were studied through single factor experiments and orthogonal experiments. The optimal extraction process are as follows:microwave extraction time 8min, temperature 60℃, liquid to solid ratio 16:1 (mL:g), and microwave power 800W. The yield of jujuboside A under the optimized process is 0.526mg/g. Compared with conventional extraction methods, the extraction yield and extraction efficiency of microwave-assisted extraction are higher than those of heat-reflux extraction, Soxhlet extraction, and ultrasonic extraction.
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    Research Progress of Methods for Improving the Performances of Waterborne Polyurethane
    WANG Hong-xiao;SHANG Shi-bin;WANG Dan;XU Xu;
    2010, 30 (1):  123-126. 
    Abstract ( 614 )   PDF (723KB) ( 754 )   Save
    Waterborne polyurethane has some drawbacks, such as poor water-resistance, low heat-resistance, low drying rate, low initial adhesion, and low solid content. Much researches to overcome these drawbacks have been carried out. Significant progress has been made in recent years. In this paper,the improvement on water resistance, heat resistance, initial adhesion, solid content and drying speed of waterborne polyurethane are summarized.
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    Detoxification of Steam-exploded Lignocellulosic Material by Ethanol Extraction
    QU Liang;XU Yong;ZHANG Hong-man;HUANG He;YING Han-jie
    2010, 30 (1):  22-26. 
    Abstract ( 609 )   PDF (770KB) ( 638 )   Save
    Inhibitors such as formic acid, acetic acid, furfural and HMF in the steam-exploded corn stover had been removed by ethanol extraction. The extraction efficiencies of inhibitors and sugars between dynamic extraction and static extraction were compared. Meanwhile, the effects of temperature, solid to liquid ratio and time on extraction efficiency in the course of static ethanol extraction had also been investigated. Based upon the results of analysis of variance of orthogonal experiment, using the ratio of total inhibitors extraction rate to total sugars extraction rate as evaluation index, the optimum experiment conditions for static ethanol extraction were obtained with the temperature 80℃, solid to liquid ratio 1:10(g:mL) and extraction time 60min. Under the optimum conditions, the extraction rates of the two most important inhibitors, namely formic acid and acetic acid, were up to 84% and 98%,respectively.
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    Antimicrobial Activities of Rosin-based Gemini Cationic Surfactants
    JIA Wei-hong;JIA Wei-hong;RAO Xiao-ping;SONG Zhan-qian
    2010, 30 (1):  1-4. 
    Abstract ( 753 )   PDF (468KB) ( 762 )   Save
    Using standard serial 2-fold agar dilution method, the antimicrobial activities of N,N,N',N'-tetramethyl N,N'-diethanolamine dehydroabietate diamine dibromide (TDDDD) and N,N,N',N'-tetramethyl N,N'-didehydroabietate diamine dibromide(TDDD), which were synthesized from dehydroabietic acid and dehydroabietylamine respectively, were determined. The bioactivity test showed that these compounds possessed good antimicrobial activities toward 7 tested bacteria.Among them,the minimal bacteriostatic concentration of 4 compounds of TDDDD against Staphylococcus epidermidis were all 16mg/L. Gemini cationic surfactants have excellent antimicrobial activity because of their higher surface activites and special structures.
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    Study on Hydrolysis and Hydrolysis Mechanism of Bagasse Sulfite Pulp by Cellulase
    WU Lian-zhen;ZHANG Jun-hua;LIN Lu;ZHUANG Jun-ping;LIU Ying;PANG Chun-sheng
    2010, 30 (1):  33-38. 
    Abstract ( 644 )   PDF (1310KB) ( 694 )   Save
    Affecting factors were studied during the hydrolysis of bagasse sulfite pulp by cellulase. Analyses on hydrolysis filtrate, the change of cellulose supramolecular structure and morphological characteristic caused by enzymatic treatment were carried out by ICS, X-ray diffraction, FT-IR and AFM. The results showed that, hydrolysis yields of bleached pulp and unbleached pulp were 74.89% and 70.67%, respectively. The hydrolysis yield of bleached pulp was lower than that of unbleached pulp under similar optimum conditions. Cellobiose concentration decreased during hydrolysis from 7.95 to 2.44g/L and from 6.59 to 3.11g/L at 6h and 72h for unbleached and bleached pulp, respectively. The crystallinity of cellulose increased after enzymatic treatment while crystal form had no transformation.
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    Preparation of Pd/C Catalyst Used for Disproportionation of Rosin
    ZHANG Jin-long;RUI Guo;GE Sheng-cai;WANG Peng-xiang;ZHANG Pei-xiang
    2010, 30 (1):  63-66. 
    Abstract ( 691 )   PDF (665KB) ( 636 )   Save
    A series of Pd/C catalysts were prepared by impregnation-reduction method, and used for the disproportionation of Masson's pine rosin. Factors influencing Pd/C catalytic activity such as particle size, carrier pretreatment and reduction condition were studied. Results showed that the Pd/C catalyst prepard from activated carbon(AC) treated with complex oxidants(10% H2O2 and 1% oxidant G )can increase the utilization rate of palladium up to 96.4% and dehydroabietic acid up to 68.4%.Through X-ray photoelectron spectroscopy(XPS), the distribution of valency of Pd in Pd/C were investigated. When HCHO amount exceeded one fold, about 44.4% Pd2+ was reduced to metallic Pd with the formation of 24.9% Pd4+ found in Pd/C catalyst. The activity of catalyst prepared under the optimized experiment conditions:obviously exceeds counterparts of other companies. Furthermore, this catalyst has been produced industrially.
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    Flash Evaporation-Gas Chromatography-Mass Spectrometry for the Analysis of Volatile Components from Curcuma wenyujin Y.H Chen et C.Ling
    WANG Li-li;CHEN Shuang;LU Lu;PAN Zai-fa;ZHANG Jun-mei;ZHOU Yan
    2010, 30 (1):  17-21. 
    Abstract ( 642 )   PDF (864KB) ( 702 )   Save
    A flash evaporation followed by gas chromatography-mass spectrometry (FE-GC-MS) for the analysis of volatile components of Curcuma wenyujin Y.H Chen et C.Ling is described. FE parameters including FE temperature, mass and particle size of sample were optimized. More than 60 compounds on the chromatogram were obtained at 200℃ of FE temperature using 0.4mg of sample of 120 μm size. The comparison among FE, steam distillation (SD) and solid-phase microextraction (SPME) was carried out. The totals of 40, 38 and 36 compounds were assigned in FE, SD and SPME, respectively, by MS combined with retention indices(RI). The relative peak areas of five active constituents (curzerene, curcumol, β-elemenone, germacrone, curdione) obtained by FE were similar to those obtained by SD and SPME. The result shows that the FE-GC-MS is a simple, convenient, sensitive and solvent-free method suitable for the analysis of volatile compounds from C.wenyujin.
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    Study on Enzymatic Hydrolysis and Adsorption Properties of Several Cellulases
    YANG Jing;ZHANG Xiao-ping;YONG Qiang;YU Shi-yuan
    2010, 30 (1):  27-32. 
    Abstract ( 705 )   PDF (1074KB) ( 741 )   Save
    The differences of proteins between cellulases from Trichoderma reesei Rut C30 produced in this laboratory and commercial cellulases were evaluated. All three cellulase preparations produced in this laboratory showed better performance than com-mericial cellulases on hydrolysis of steam-exploded and dilute-acid-pretreated corn stover. The cellulase, produced from steam-exploded corn stover, could obtain hydrolysis yield of 90.08% on steam-exploded corn stover through supplementing β-glucosidase of 8IU/g cellulose; the content of cellobiose was decreased from 17.06 to 1.12g/L; the content of glucose was increased from 21.09 to 44.01g/L and the ratio of fermentable sugar was enhanced from 55.28% to 97.52%. The adsorption of cellulases protein on microcrystalline cellulose reached equilibrium in 30min. From the Langmuir adsorption isotherm, all cellulases had similar affinity for microcrystalline cellulose and maybe derived from Trichoderma reesei.
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    Study on Morphological Characteristics of Sweet Bamboo Fiber from Vietnam
    CAO Quoc-an;LI Zhong-zheng
    2010, 30 (1):  39-42. 
    Abstract ( 519 )   PDF (701KB) ( 698 )   Save
    The fiber morphology of sweet bamboo (Dendrocalamus latiflorus Munro.) materials and sweet bamboo pulp from Vietnam had been studied. The results show that:average fiber length of sweet bamboo materials is 2.37mm, average width of fiber is 17.91μm, the average length/width ratio is 132.40; average wall thickness is 8.13μm, average cavity diameter is 2.57μm, the average wall/cavity is 6.33. The change of fiber morphology during cooking process is researched, the results show that, fiber length in the process of cooking decreased constantly, from 2.37mm(raw material) to 1.79mm(pulp), or reduced 24%, length/width ratio of fiber also decreased constantly, from 132.40(raw material)to 98.89(pulp). Compared with Bambusa textilis McClure pulp, Pinus massoniana Lamb. pulp, eucalyptus wood pulp and wheat straw pulp (grass type), the fiber length of sweet bamboo pulp fiber is greater than wheat straw pulp fiber and less than P.massoniana pulp, and similar to B.taxtilis pulp and eucalyptus wood pulp. Thus sweet bamboo fibers belongs to long fiber, which is a good paper-making raw material.
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    Extraction of Flavonoids from Leaves of Acer truncatum Bunge
    YANG Zhen-ping;BIAN Qing-quan;YANG Kui-hua;YANG Chi;LUO Jin
    2010, 30 (1):  77-80. 
    Abstract ( 545 )   PDF (736KB) ( 656 )   Save
    Extraction technology of quercetin and kaempferol from leaves of Acer truncatum Bunge was optimized.The effect of factors on extractive yield was studied using orthogonal experiment to investigate the ratio of material to liquid,the time of extraction and the times of extraction.The optimized conditions were:ratio of water to material 20:1, two times of extraction and each 3h. Under the optimized experiment conditions, extractive yield was 1.02%, the content of kaempferol in the product was 50.4mg/g with relative standard deviation(RSD) of 2.2%, and the content of quercetin was 48.2mg/g with the RSD of 1.6%. These two active components in sample can be extracted efficiently by using this technology which was economical and environmental-friendly.
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    Influence of Microwave-assisted Alkali Pretreatment on Structure and Cyanoethylation Performance of Secondary Fiber
    ZHANG Chun-hong;CHEN Qiu-ling;SUN Ke-wei
    2010, 30 (1):  97-102. 
    Abstract ( 601 )   PDF (1290KB) ( 698 )   Save
    Microwave-assisted alkali treatment was applied to pretreatment of secondary fiber(SF) to improve its reactivity. The changes of chemical composition, supramolecular structure and physical characteristics of SF after activation were studied. The mechanism of microwave-assisted alkali pretreatment of secondary fiber(WASF) was discussed. The results showed that crystal form of SF was not changed, but the crystallinity of SF was decreased, hydrogen bonds among SF molecules were partially destroyed, fiber surface was damaged. These changes resulted in the increases of accessibility, specific surface area and reactivity of SF. Under similar microwave irradiation power, prolonging of irradiation time is beneficial to cyanoethylation of SF. Furthermore, nitrogen content of cyanoethylated SF was improved from 10.85% to 17.80%.
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    Study on Extraction and Antioxidation Property of Polyphenol from Chestnut Shells
    LI Jin-feng;DUAN Yu-qing;MA Hai-le;ZHANG Hai-hui;XU Fei-fei;HUANG Liu-rong
    2010, 30 (1):  53-58. 
    Abstract ( 806 )   PDF (1133KB) ( 923 )   Save
    The effects of different factors on extraction of polyphenol from chestnut shell were studied, and the antioxidation pro-perty of polyphenol of chestnut shell was also studied. The results showed that the optimum extraction conditions were:ethanol volume fraction 59.7%, solid-liquid ratio 1:18(g:mL), extraction temperature 52.6℃ and extract 3 times. The predicted yield of chestnut shell polyphenol is 76.0mg/g and the test result is 75.9mg/g. Polyphenol in chestnut shell has strong ability to eliminate free radicals. The abilities of reducing and removing DPPH·,·OH, O2-· gradually increased with the increase of concentration in the range of 25 to 200mg/L. The ability of reduction reached 0.841, and the rate of inhibition reached 89.7% at 200mg/L, which are higher than those of 2,6-di-tert-butyl-p-cresol (BHT) but lower than those of VC, at similar mass concentration. The removal rates of O2-· and ·OH are 93.2% and 94.0%, respectively, at concentration of 200mg/L, which are higher than BHT and Vc.
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    Graft Copolymerization of Methyl Methacrylate with TMP Pulp Using Fe2+-H2O2-Thioureadioxide Initiating System
    LIANG Xi-lin;ZHAI Hua-min
    2010, 30 (1):  59-62. 
    Abstract ( 584 )   PDF (835KB) ( 659 )   Save
    Graft copolymerization of thermomechanical pulp(TMP) with methyl methacrylate (MMA) using Fe2+-H2O2-thiourea-dioxide(TD) initiating system was studied. The effects of reaction factors on grafting rate, grafting efficiency and monomer conversion ratio were identified. Results showed that the addition of thioureadioxide can proceed the graft copolymerization successfully. Proper increases of temperature, monomer concentration, and maintaining proper thioureadioxide dosage were beneficial to the grafting rate, grafting efficiency and conversion ratio. Graft copolymerization in this system can be completed successfully and grafting efficiency was generally maintained at over 80%, and even up to 91% under proper reaction conditions.
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    Optimization of the Processing Parameters for Extraction of Antioxidants from Blackberry Using Response Surface Methodology
    YANG Ling;WANG Zhen-yu;
    2010, 30 (1):  67-72. 
    Abstract ( 582 )   PDF (1104KB) ( 790 )   Save
    The conditions of ultrasonic extraction of antioxidants from blackberry were studied by response surface method using the removal rate of 1,1-diphenyl-2-picryhydrazyl redical(DPPH·) as evaluation index, based on single factor experiment of liquid-solid ratio, ultrasonic time,extraction temperature, ultrasonic power and ethanol volume fraction. The results showed that the optimal extraction conditions were:fresh fruits of blackberry 2.5g, liquid-solid ratio 26:1, ultrasonic temperature 52℃, ultrasonic power 160W, ethanol volume fraction 53%.Under these conditions, the removal rate of DPPH· was 67.13%.
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    Progress of Research on Catalytic Hydrogenation of Rosin
    YU Ming-yuan;LIU Shi-wei;XIE Cong-xia;JIANG Rui;YU Shi-tao;LIU Fu-sheng
    2010, 30 (1):  111-115. 
    Abstract ( 641 )   PDF (858KB) ( 769 )   Save
    The noble metal palladium catalyst, skeleton nickel catalyst and nano-nickel catalyst used for rosin hydrogenation as well as reaction kinetics of rosin hydrogenation are summarized. Various strong points and weaknesses of the catalysts for rosin hydrogenation are reviewed, and it is indicated that the future study on hydrogenation of rosin should be mainly concentrated on the preparation of new and cheap catalysts with high activity and selectivity under low pressure and temperature.
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    Characterization of Chitosan-carboxymethyl Cellulose Blended Membrane
    ZHANG Rui;FANG Gui-zhen;MA Ying-mei;MA Yan-li
    2010, 30 (1):  43-48. 
    Abstract ( 815 )   PDF (1796KB) ( 755 )   Save
    Carboxymethyl cellulose-chitosan (CMC-CS) blended membranes with different weight ratios(1:2, 1:1, 2:1) were prepared by co-solution method. The structure of membranes was characterized by FT-IR and SEM. The thermal property of membranes was characterized by DSC. The properties of CMC-CS were evaluated by uniformity, acid resistance, tensile strength and absorption rate. The intermolecular mechanism was analyzed. The results indicated that CMC and CS generated polyelec-trolyte through electrostatic and hydrogen-bond interactions. The intermolecule bonds of CMC-CS membranes were degraded between 170℃ and 330℃. At 217.4℃, the ionic bonds were fractured and the electrostatic interaction disappeared. The CMC-CS membrane with a weight ratio of 1:1 was the ideal membrane, whose electrostatic interaction between CS and CMC was the highest. Tensile strength of the CMC-CS membrane reached 34.44MPa, which was 64.47% higher than CS membrane. The maximal acid adaptability was decreased from pH value 5 to 4, and tensile strength of CMC-CS membrane was 25.71MPa after dunking at pH value 6. The water-swelling rate of CMC-CS membranes was effectively reduced.
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    Study on Curie-point Pyrolysis of Xylan under CP-GC-MS Conditions
    LIU Jun-li;JIANG Jian-chun;HUANG Hai-tao
    2010, 30 (1):  5-10. 
    Abstract ( 666 )   PDF (1361KB) ( 709 )   Save
    The influence of temperature on the relative content of pyrolysis products obtained by Curie-point pyrolysis of xylan,which was considered as the model compound of hemicelluloses, was investigated by Curie-point pyrolysis-gas chromatography-mass spectroscopy( CP-GC-MS), and pyrolysis behavior of xylan was contrasted with cellulose. The results showed that the process of xylan Curie-point pyrolysis could be divided into two regions. At the temperature of less than 300℃, xylan by random glycosidic cleavage of xylan was cleaved to form furfural and monosaccharides, where furfural content reached 54.38% in the pyrolysate. At the temperature of more than 300℃, the kind and content of chemicals of small molecular aldehyde and ketone were increased greatly with the enhancement of pyrolysis temperature. The difference of pyrolysis behaviors between xylan and cellulose was that pyrolysis temperature of xylan was lower than that of cellulose, and the main pyrolysis product from xylan was furfural, while that of cellulose was levoglucosan.
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    Study on Chemical Constituents of Lonicera dasystyla Rehd.
    LUO Yong-jing;LI Hui-jun;LI Ping;ZHANG Li;BI Zhi-ming
    2010, 30 (1):  73-76. 
    Abstract ( 620 )   PDF (721KB) ( 818 )   Save
    Chemical constituents from the flower buds of Lonicera dasystyla Rehd. were studied. Ten compounds were isolated and their structures were elucidated as chlorogenic acid (Ⅰ), 5-O-caffeoyl quinic acid butyl ester (Ⅱ), 5-O-caffeoyl quinic acid methyl ester (Ⅲ), quercetin (Ⅳ), luteolin-7-O-β-D-glucoside (Ⅴ), rutin (Ⅵ), kaempferol-3-O-rutinoside (Ⅶ), aesculetin (Ⅷ), β-sitosterol (Ⅸ), daucosterol (Ⅹ). Compounds Ⅰ,Ⅱ,Ⅲ,Ⅴ,Ⅵ,Ⅷ,Ⅸ,Ⅹ were firstly isolated from this species, while compound Ⅶ was isolated from genus Lonicera for the first time.
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    Chemical Compositions of Theabrownin Extract from Pu-erh Tea during Fermentation by Different Microorganisms
    YANG Da-peng;SHI Wen-bin;CHEN Yi-jiang;GONG Jia-shun
    2010, 30 (1):  49-52. 
    Abstract ( 1002 )   PDF (759KB) ( 784 )   Save
    The variation of contents of theabrownin(TB), protein, polysaccharide, theaflavins(TF) and thearubigin(TR) in TB extracts from different piled-up samples of Pu-erh tea during fermentation by different microorganisms were studied. The contents of TB, polysaccharide and protein from extracts were increased during fermentation. Comparied with increasing of the content of TB, the content of TF and TR were reduced during fermentation. Moreover, the reduced values of TF and TR are less than the increased value of TB. In the last piled-up samples fermented with Trichoderma reesei, Aspergillus niger, yeast, Aspergillus oryzae and Rhizopus, the mass fractions of TB in different TB extracts were 35.30%, 43.50%, 39.21%, 44.83% and 39.56%, respectively; the contents of theaflavin were 0.85%, 0.77%, 0.75%, 0.77% and 0.89%, respectively; the contents of thearubigin were 0.53%, 3.49%, 0.26%, 4.00% and 3.30% respectively; while the contents of polysaccharide were 27.81%, 23.35%, 33.09%, 21.11% and 27.14%, respectively, and the contents of protein were 28.57%, 26.96%, 26.44%, 26.00% and 26.61%, respectively, suggesting that chemical compositions among TB extracts from tea samples fermented by different microorganisms had significant difference.
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