用户名: 密码: 验证码:
固定化细胞生物转化半纤维素水解液生产木糖醇
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
本论文的研究工作包括;玉米芯酶水解液的制备,玉米芯半纤维素水解液发酵生产木糖醇,微胶囊固定化方法发酵玉米芯水解液等内容进行了综述和分析。通过比较深入的研究工作,取的研究成果包括:
     选用了高温蒸煮使木聚糖溶出,对蒸煮时间,蒸煮温度,固液比等条件做了研究,得出的结论是:将的玉米芯经5%氨水在60℃条件下浸泡12h,滤去浸泡液,水洗至中性,加水至固液比为1:10的比例,于170℃下密封蒸煮2h。将高温蒸煮液,加木聚糖酶水解,对酶解的条件进行了优化,最佳条件是高温蒸煮液加6%的酶量,在pH4.0,在45℃下搅拌速度为200r/min条件下,酶解8h。
     研究结果表明,以玉米芯酶解液为底物摇瓶发酵生产木糖醇,最适的条件为:实验条件下20h的种子龄为最佳,初糖的浓度为40g/L、装液量为250mL的三角瓶装100mL的培养基、接种量为5%(体积比)、起始pH6.0,氮源组成:酵母膏和蛋白胨各2.5g/L、温度为30℃。在此条件下,木糖醇的得率可达到66.35%。在此基础上本文还研究了发酵罐中通气量对酵母发酵玉米芯酶水解液生产木糖醇的影响。结果表明:其中0h-20h,2vvm的通气量;20h-80h,1.0vvm的通气量,有利于木糖醇的积累。
     本文采用壳聚糖-海藻酸钠微胶囊化酵母细胞,采用的微囊化的条件是,2.5%海藻酸钠溶液以1:5(v/v)的比例混和,通过注射器滴入浓度为1.5%的氯化钙溶液,钙化4小时,制得的海藻酸钙胶珠置于0.5%pH=6的壳聚糖溶液(溶于1.0%乙酸)中成膜15min;洗净后,最后在0.055mol/ml的柠檬酸溶液中液化25min。对影响微胶囊化细胞发酵的因素进行了正交试验,确定了在摇瓶中固定化细胞发酵发酵玉米芯半纤维素水解液的过程中,摇床的转速对木糖醇产量的影响最大,经过优化较好的发酵条件是,摇床转速其中0-20h,200r/min,20-64h,140r/min氮源含量3g/L酵母膏,3g/L的蛋白胨,固定化细胞凝胶珠与玉米芯半纤维素水解液体积比为1:3。
     对壳聚糖-海藻酸钠微胶囊固定化,游离细胞,海藻酸钙固定化细胞发酵进行了比较,发现微胶囊固定化具有游离细胞和海藻酸钙固定化细胞发酵两者的特点。微胶囊固定化的发酵木糖醇得率比海藻酸钙固定化细胞发酵高为60.1%,而
    
    浙江工业大学硕士论文
    摘要
    海藻酸钙固定化细胞发酵的木糖醇得率为49.3%。另外,微胶囊细胞发酵的发酵
    周期与固定化细胞相似发酵周期为64h,游离细胞发酵周期为72h。比游离发酵
    缩短10h左右。最后在摇瓶条件下,采用分批发酵方式,对微胶囊细胞的发酵玉
    米芯酶水解液进行重复8批25d发酵,木糖醇得率平均为61.4ry0。
     通过本文的研究,初步探讨了玉米芯酶解液发酵木糖醇的可行行,为进一步
    的研究提供了依据。
The research work in this thesis includes: preparation corn cob hemicellulosic enzymatic production and xylitol fermentation from corn cob hemicllucellulosic, enzymatic hydrolysate , microcapsule was applied in xylitol of corn cob hemicellulosic enzymatic hydrolysate
    Corn cob is composed of lignin cellulose and hemicellulose.It is difficulte to directly enzymatic hydrolysate.we must be pretreated .we select high temperature cooking solubility of the xylan . the optimum conditions were as follows:corn cob was pretreated by 0.1% acid at 60℃ for 12h. The best proportion of corncob with the water is 1 :10, high temperature cooking temperature is 170℃, reaction time is 2h. the optimum conditions of enzymatic hydrolysate as follows: xylanase 6% , at pH4.0 ,45℃, 200r/min reaction 8h in xylitol fermentation of corn cob hemicellulosic enzymatic production, the optimum conditions were as follows:xylose 40g/L, culture medium 100 ml in 250 ml flask, inoculum size, 5%; inoculum age, 20 h; nitrogen source. 2.5 g/L Bacto-yeast extract and 2.5 g/L Bacto-tryptone,temperature 30℃,In this condition ,the highest xylitol yield 66.35%.In order to evaluate the effect of aeration rate on the xylitol fermentation on corn cob hemicellulosic enaymatic production in fermentator ,batch fermentation
    were carriec out two-stage aeration strategies,which provided relative higher aeration rate in the early stage but reduced it in the later stage,and including a one-stage aeration strategy that it provbided a constant aeration rate.The two-stategy oxygen supply strstegy is 2.0wm for the fist 20h,then lowered it to 1 .0vvm.
    The preparation process of chitosan-alginate microcapsule is 0.5%chitosan solution (dissolved in 1% HAc, pH 6) and a simple droplet generator were employed to form chitosan-alginate microcapsules The best reaction time of the membrane's construction of microcapsules was found to be 15min, and the best reaction time of the liquefying of microcapsules to be 25min.
    Chitosan-alginate microcapsule was applied in xylitol batch fermentation. The
    
    
    microcapsules were used repeatedly in four batches. It was found that the fermentation with microcapsules had better and fixed conversion (55.17%), comparing with free-cells fermentation (changed from 67.5% to49.87%) and Ca-alginate immobilizing fermentation (changed from 41.23% to 45.67%), while the end time of microcapsule fermentation was enhanced and fixed to 64h.
    The chitosan-alginate microcapsuleused for xylitol productin on corn cob hydrolysates. The optimum batch fermtentation conditions was as follows:shaking speed was divided into two stages:200r/min 0-20h,140r/min at 20-64h. nitrogen source. 2.0 g/L Bacto-yeast extract and 2.0g/L Bacto-tryptone,the volume propotion between gel beads of immobilized cells and hydrolysates.
    The research work of thesis developed an xylitol fermentation process using corn cob hemicellulosic enzymatic hydrolysate in stead of acid hydrolysate .The technology is of importang value.
引文
1.尤新.木糖醇的生产和应用,北京:轻工业出版社,1984.
    2. MSYERHOFF Z D, ROBERTO I C, SILVA S S.Production of Xylitol by Candida mogii fromRice Straw Hydrolysate [J].Applied Biochemistry and Biotechnology, Vol. 70-72, p 150-159.1998
    2 Hyvonen L, Koivistoinen P, Voirol F. In Advances in Food Research, Vol. 28, eds Chichester CO, Mrak E M, Stewart G, p. 373-403, Academic Press, New York.
    3 吴星,木糖醇微生物转化的研究[J],工业微生物,Vol,24,N04,p:24-26,1994.
    4 张厚瑞,半纤维素水解物生物转化生产木糖醇[J],生物工程学报,Vol.16,NO.3,p.304-307,2000
    5 TIHANY A M, SILVA S S, Inhibition of Microbial Xylitol Production by Acid Its Relation with Fermentative Parameters [J],Applied Biochemistry and Biotechnology, Vol. 84-86, p:801-807,2000.
    6 PARAJO J C, et al. Biotechnological production of xylitol. Part 1: Interest of xylitol and fundamentals of its biosynthesis [J], Bioresource Technology, Vol. 65, p:191-201,1998.
    7 LEE, H ATKINS, A. BARBOSA, M FS. effect of biotin limitation on the conversion of xylose to ethanol and xylitol by pachysolen tannophilus and candida guilliermondii[J],Enzyme and Microbial Technology, Vol. 10, p:81-84,1988.
    8 VONGSUVANLERT V, TANI Y J Xy litol production by a methanol yeast, Candida boidinii (Kloeckera sp.) No. 2201[J], Journal of Fermentation and Bioengineering, Vol. 67, p:35-39,1989.
    9 HORITSU H, YAHASHI, Y TAKAMIZAWA K, et al. Production of xylitol from d-xylose by candida tropicalis: optimization of production rate[J],Biotechnoiogy and Bioengineering, Vol. 40, p:1085-1091,1992.
    10 RAHMAN K A, TOKUNAGA H, YOSHIDA K, et al. Conversion of xylitol to L-xylulose by Alcaligenes sp. 701B-cells[J]Journal of Fermentation and Bioengineering, Vol. 72, p:488-490,1991.
    11 GIRIO F M., ROSEIRO J. C,. RITA M.T et al. Effect of oxygen transfer rate on levels of key enzymes of xylose metabolism in Bebaryomyces hansenii[J] Enzyme and Microbial Technology, Vol. 16, p: 1074-1078, 1994.
    12 MONINUZZMAN M, et al. Fermentation of corn fibre sugars by an engineered xylose utilizing Saccharomyces yeast strain [J], World Journal of Microbioloby &Biotechnology, Vol. 13, p341-346,1997.
    13 LATIF F, RAJOKA M I, Production of ethanol and xylitol from corn cobs by yeasts [J], Bioresource Technology, Vol.77, pp:57-63,2001.
    15 沈同,王镜岩,生物化学(上),第二版,p:129-130,1990.
    16 GONG C S, et al. Conersion of Pentoses by Yaests[J],Biotechnology and Bioengineering Vol. 25, p. 85-102,1983.
    17 POONAM N, SINGH D, Processes for Germentative Production of Xylitol-a Suga Substitute [J],Process Biochemistry, Vol. 30,,no. 2, pp. 117-124,1995.
    18 BARBOSA M F A, et al. Screening of yeasts for production of xylitol from D-xylose and some factors which affect xylitol yield in Candidaguiliiermondii[J]Process
    
    Biochemistry, Vol. 3, pp:241-251,1988.
    19 PARAJO J C, DOMINGUEZ H, and DOMINGUEZ J M, Production of xylitol from concentratedwood hydrolysates by Debaryomyces hansenii: effection of the initial cell congcentration [J] Biotechnology Letters, Vol,18,No. 5, pp: 593-598,1998.
    20 KASTNER J R, ROBERTS R S,JONES W J, Effects of pH oh cell viability and product yields in D-xylose fermentations by Candida shehatae [J],Appl Microbiol Biotechnol, Vol. 45, pp. 224-228,1996.
    21 MARIA G A, et al. Fermentation of sugar cane bagasse hemicellulosic hydrolysatefor xylitol production :effect of pH[J],Bioresource and Bioenergy, Vol. 11, Nol12, pp. 11-14,1997.
    22 CONVERTI A, PEREGO P, DOMINGGUEA J, SILVA S S, Effect of temperature on the microaerophilic metabolism of Pachysolen tannophilus [J], Enzyme and Microbial Technology, Vol. 28, pp:339-345,2001.
    23 MARINEZ E A, Effect of the Oxygen Transfer Coefficient on Xylitol Production from Sugarcane Bagasse Hydrolysate by Continuous Stirred-Tank Reactor Fermentation[J], Applied Biochemistry and Biotechnology, Vol, 98-100, pp:1049-1058, 2002.
    24 ANTINIETA A, Oxyen Uptake Rate in Prodution of Xylitol by Candida guilliermondiiwith Different Aeration Rates and Initil Xylose Concentrations [J],Applied Biochemisty and Biochmeistry and Biotechnology, Vol. 98-100, pp:1049-1058,2002.
    25 TAVARES J M,, et al., The influence of hexoses addition on the fermentaton of D-xylose in Debarymyces hansenii under continuous cultivation[J],Enzyme and Microbial Technology Vol. 26, pp743-747,2000.
    26 ALVES L A, et al. Xylose Reductase and Xylitol Dehydrogenase Acticities of Candidan guilliermondii as a Empolying Experimentat Design [J],Applied Biochemistry and Biotechnology ,Vol 98-100, pp403-401,2002.
    27 MAYERHOFF Z D V, ROBERTO I C, SILVA S S, Production of Xylitol by Candida mogii from Rice Straw Hydrolysate [J],Applied Biochemistry and Biotechnology, Vol .26, pp:743-747,2000.
    28 JOSE M, DOMINGUE Z, et al. Dilute acid hemicellulose hydrolyzates from corn-cobs for xylitol production by yeast [J],Bioresource Technology, Vol .64, p:85-90, 1997.
    29 M J VAZQUEZ, et al. Production of xylose-containing fermentation media by enzymatic post-hydrolysis of oligomers produced by corn cob autohydrolysis[J].W J. Microbiol and Biotechnol. Vol. 17, p:817-822,2001.
    30 邬义明,植物纤维化学[M],北京:中国轻工业出版社,1991。
    31 SUNNAA, ANTRANIKIANG. Xylanolytic enzymes from fungi and bacteria. [J] Critical Rev Biotechnol, Vol. 17, p:39-67,1997.
    32 JOSELESU JP, COMTAT J, RUEL K. Chemistry structure of xylans and their interaction in the plant cell wall. Xylans and Xylanase. Amsterdam: Elsevier,.p:1-15,1992.
    33 PULS J, SCHUSED J. Chemistry of henucelluloses: relationship between
    
    hemicellulose structure and enzymes required for hydrolysis..Hemicellulose and Henricellulases. Imdon: Portland Press, p:1-27,1993.
    34 WONG KKY, TAN LUL, SADDLER JN. Multiplicity of E3-1,4-xy-lanase in microorganisms: function and applications. [J], MicrobiRev, Vol52, p:305-317, 1988.
    35 COUGHAN MP, HAZLEWOOD GP. P-1, 4-D-Xylan-degrading enzyme systems: biochemistry, molecular biology and application. [J], Biotechnol Appl Biochem, Vol. 17, p:259-289,1993.
    36 KAWHIKO NISHITANI, NEVINS DJ. Glueuronoxylan xylanohydrolase: An unique xylanase with the requirement for appendantglucuronosyl units. [J]J Biol Chem. Vol. 266, p:6539~6543, 1991.
    37 CONRAD D, NOETHEN W. Hydrolysis of cyclodextrins (DP 2-6)by xylanolytic enzymes from Aspergillus niger. Proc 3rd EurCongr Biotechrwl, Vol. 2, p:169-177,1984.
    38 MCDERMID KP, FOSBERG CW, MACKENZIE CR. Purification andproperties of an acetyl xylan esterase from Fibrobacter succinogenes S85[J].Appl Eroviron Microbial, Vol. 56, p:3805-3810,1990.
    39 BOMEMAN WS, LJUNGDAHL LG, ROY D et al. Feuloyl and pcoumaroyl esterases from the anaerobic fungus Neoaallimastix strain MC-2: properties and functions in the plant cell walldegradation. In: Coghlan MP, Hazelwood GP (eds).Hemicellulose and Hemicellulases. London: Portland Press, p:85-102,1993.
    40 HAZLEWOOD GP, GILBERT HJ. Molecular biology of hemicellulases. In: Coghlan MP, Hazelwood GP (eds). Hemicelluloseand Hemicellulases. London: Portland Press, p:103-126,1993.
    41 PHILIPPE D, BERNARD P, GERALD S et al. Purification andproperties of an endo-1, 4-Xylanase excreted by a hydrolyticthermophilic anaerobe, Clostridium therrnolacEicum: A proposal for its action mechanism, larchwood 4-O-methylglu-curonoxylan. [J] Eur J Bwchern, Vol. 187, p:573—580,1990.
    42 HARDY LW, POTEETE AR. Reexamination of the role of Asp~(20) incatalysis by bacteriolrage T_4 lysozyme. [J] Biodianistry, Vol. 30, p:9457-9463,1991.
    43 CABASSO, ISRAEL, Microcapsules For Controlled Release Via Donnan Dialysis [J], Journal of Membrane Science, Yol. 7, p: 305-318,1998.
    44 ULUDAG, HASAN SEXTON, MICHAEL V .Metabolic activity of CHO fibroblasts in HEMA-MMA microcapsules Source: Biotechnology and Bioengineering, Vol. 39, p: 672-678,1992.
    45 FORSTER, MICHAEL MANSFIELD, JOANNA; SCHELLENBERGER, ALFRED; DAUTZENBERG, Immobilization of citrate-producing Yarrowia lipolytica cells in polyelectrolyte complex capsules [J]Enzyme and Microbial Technology, Vol.16, p: 777-784,1994.
    46 解玉冰,马小军等,第七届全国生物化学会议论文集,北京:化学工业出版社,p:154-157,1996.
    47 吕秀菊,丛威,et al.微胶囊技术及其在核/壳型微载体制备中应用。第九届全国生物化公学术论文集。天津:天津大学出版社,p:284-289,2000.
    48 虞星炬,解玉冰,et al.生物微胶囊技术的研究进展.第七届全国生物化工学术会议论文集,p:11-15,1996.
    
    
    49 王勇,解玉冰,马小军,壳聚糖/海藻酸钠生物微胶囊的研究进展。生物工程进展,19:p:13-16,1999.
    50 ALEXAKIS Bacillus sphaericus 2362-calcium alginate microcapsules for mosquito control [J]Enzyme and Microbial Technology, Vol. 17, p: 587,1995.
    51 付颖丽,雄鹰,微胶囊应用前景的研究第九届全国生物化工学术会议论文集。天津:天津大学出版社 p:151-153.2000.
    52 POLK A Controlled release of proteins from poly(L-lactic acid) coated polyisobutylcyanoacrylate microcapsules[J] Journal of Applied Polymer Science, Vol. 52, p: 1797-1807,1994.
    53 GOOSEN, M.F.A.; KING, G.A.; MCKNIGHT, C.A.;Animal cell culture engineering using alginate polycation microcapsules of controlled membrane molecular weight cut-off[J],Journal of Membrane Science, Vol. 41, p: 323-343,1989.
    54 BLANCHE DE. GAILARD..Comparison of the Hemicelluloses from plants Belong to Different Plant Families[J] Phytochemistry. Vol4, p:631-634,1965.
    55 B.J. DONNELLY, JL. HELM, AND H.A. LEE.. The Carbohydrate Composition of Corn Cob Hemicelluloses. Corn Cob Hemicelluloses. Vol. 50:549-552,1973.
    56 SPYROS G.P AND JAMES M Treatment of Wheat Straw for Increasing Anaerobic[J] Biodegrability. Biotechnology and Bioengineering. Vol. 27:334-344,1985.
    57 LIISA VIIKARI, ANNE KANTELINEN, JOHANNA, Enzymatic accessibility of xylans in lignocellulosic materials. [J]Appl. Microbiol. Biotechnol. Vo144, p:124-129, 1994.
    58 唐爱民,梁文芷,纤维素预处理技术的发展,林产化学与工业,19(40)p:81-89,1999.
    59 GUIDO Z. Economic Evaluation of Enzymatic Hydrolysis of Phenol-Pretreated Wheat Straw. Biotechnology and Bioengineering. Vol. 32, p:460-466,1988.
    60 MARINEZ E A, Effect of the Oxygen Transfer Coefficient on Xylitol Producting from Sugercane Bagasse Hydrolysate by Continuous Stirred-Tank Reactor Fermentation [J].Applied Biochemistry and 8iontechnology, Vol.84-86, pp:633-641,2000.
    61 POONAMN, SINGH D, Processes for Fermengative Production of Xylitol-a Sugar Substitute[J],Process Biochemistry, Vol.30, No. 2, pp:117-124,1995.
    62 KIM S Y, KIM J H, OH D K. Improvement of zylitol production by controlling oxygen supply in Candida parapsilosis[J].J Ferment 8ioeng Vol 83:267-270,1997.
    63 MARTINES E A, SILVA S S, FELIPE M G A. Effect of the transfer coefficieng on zylitol production from sugarcane bagasse hydrolysate by continuous stirred -tank reactor fermentation [J].Appl Biotechnol, 84-86:633-641,2000.
    64 JEN A C, CONLEY W and MINOS A G, Review:Hydrogels for cell immobilization [J],Biotechnology and Bioengineering, Wol. 50, pp. 357-364,1996.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700