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Screening of three straw-cellulose degrading microorganism

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The aim of this study was to screen straw-cellulose degrading microorganisms and to investigate their degradation ability of straw-cellulose. The methods used to screen the high effect straw-cellulose degrading microorganism included the traditional isolation methods of straw-cellulose degrading microorganism such as holes observation method on filter paper sheet, disintegration test of filter paper scrip, hydrolysis spot diameter measurement method of CMC-Na, weight lose assay method of straw, measurement method of cellulose decomposition rate, measurement method of extracellular enzyme activity. We isolated 3 fungi with cellulose degrading ability, of which 98MJ was identified as Penicillium oxalicum, W3 as Trichoderma sp., and W4 as Penicillium expansum. Strain W4 possessed high straw-cellulose degrading ability with straw-cellulose degrading rate of 56.3%, cellulose 59.06%, hemicellulose 78.75% and lignin 33.79% in 10 days. Strain W4 was a cellulase-producing strain with broad development potential.
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Research Paper 研究报告
微生物学报 Acta M icrob iologica Sinica
507870 - 875 4 July 2010
ISSN 0001 - 6209 CN 11 - 1995 / Q
http/ /journals. im. ac. cn / actamicrocn
基金项目
十一五
国家科技支撑计划项目2007BAD89B13国家高技术研究发展计划863 2006AA10Z426
*通信作者Tel+ 8 6-10 -8210621 2E-mailBqfan@ caas. ac. cn
作者简介王洪媛1976
山东莱州人
助研
博士
主要从事农业微生物资源与利用的研究E-mailwanghy@ caas. ac. cn
收稿日期2009 -12-03修回日期2010-04-19
三株高效秸秆纤维素降解真菌的筛选及其降解效果
王洪媛
范丙全*
中国农业科学院农业资源与农业区划研究所
100081
利用多种筛选方法
获得高效秸秆纤维素降解真菌
研究秸秆维素解能
方法
采用滤纸片孔洞法
滤纸条降解法
羧甲基纤维素钠CMC-Na水解圈测定法
失重
素分
定法
胞外酶活测定法等常规秸秆纤维素降解菌的筛选方法
筛选到 3株具有较强纤维素降解能力
真菌
经初步鉴定菌株 98MJ 为草酸青霉Penicillium oxalicum
W3 为木Trichoderma sp .
W4 扩张Penicillium expansumW4 具有非常强的秸秆纤维素降解能力10 d 内对秸秆的降
率可56. 3%
纤维
纤维和木59. 06% 78. 75% 33. 79% W4
胞外素酶力在 14. 25 - 49. 75 U / mL 之间。【
筛选获得 3株高效秸秆纤维素降解真菌菌株
W4 的纤维素酶活高于已报道的菌株
是一株十分具有研究开发潜力的纤维素酶生产菌株
关键词秆纤降解菌纤维素酶
图分Q935 文献标识码A文章编号0001-6209 201007 -0870-06
农作物秸秆是自然界蕴藏最丰富的可再生资
秸秆纤维素的生物转化近些年受到了广泛关
大规模纤维素生物转化工艺的发展
将有效解决
减轻品和物饲不足
废弃物处理
矿石燃
依赖1自然界中能够降解纤
素 的 微 生 物 很 多2 - 3
担 子 菌虫 拟 蜡 菌
Ceriporiopsis subvermispora 木 腐 菌粉孢革菌
Coniophora puteana Coniophora
cerebella 半知菌康 宁 木 霉 Acrostalagmus
koningii和里氏木霉 Trichoderma reesei
目前所应用和研发的菌株仍然存在着秸秆纤维素降
活性不稳定
产酶成本高
pH
窄等因此
获取高效降解秸秆纤维素的微
生物菌株及其制剂的应用是解决秸秆问题的关键技
目前我国科研工作者在筛选秸秆降解菌的过程
要采的方滤纸片孔洞法
滤纸条降解
甲基
纸或
秸秆纤维素分解率测定法
本研究的主要目的是要综合利用这些方法筛选
获得高效秸秆纤维素降解菌并研究其纤维素酶的活
时期找到
素降解菌的筛选方法
1材料和方法
1. 1
1. 1. 1 采集自东北漠河
京郊的森
土壤
腐烂的秸秆
烂的材以堆肥
1. 1. 2 主要试剂仪器DNS 试剂
柠檬酸缓冲液
杨素Sigma
羧甲基纤维素钠团化
试剂有限公司新华定性滤纸秸秆
将小麦秸秆剪成 2 - 3 cm 小段
烘干后粉碎至
王洪媛等三株高效秸秆纤维素降解真菌的筛选及其降解效果. /微生物学报201050 7
60
2 %
1∶ 4
85 水浴中处理 1 h
pH 为中性
干备秸秆木质纤维素中的纤维素
木质素和
半 纤 维 素 的 含 量 分 别 为 39. 57% 34. 83%
24. 77%
1. 1. 3 1Huchinson
KH2PO41. 0 gNaCl 0. 1 gMgSO4·7H2O
0. 3 gNaNO32. 5 gFeCl30. 01 gCaCl20. 1 g
1000 mLpH7. 2 2滤纸培养基赫奇逊氏
机盐养基添加18 g / L
片三滤纸3CMC-Na 平板培
CMC-Na 10. 0 g200 g 去皮马铃薯汁1000 mL
18 g
蒸馏pH7. 2 4
用马蔗糖琼脂PDA 5
发酵KH2PO41. 0 gNaCl 0. 1 gMgSO4·
7H2O 0. 3 gNaNO32. 5 gFeCl30. 01 gCaCl20. 1 g
秆木20 g 10 gpH 7. 2
7. 4
1. 2 滤纸片孔洞法富集初筛秸秆纤维素降解菌
采用滤纸片孔洞法进行秸秆纤维素降解菌的初
用无菌水浸泡采集的土壤
腐烂的秸秆及木材等
在摇床振荡 30 min
取样品悬液
用无菌水稀
10 - 1 10 - 2 10 - 3 浓度
吸取稀释浓度为
10 - 3 的稀释液
涂在滤纸培养基上
28 ℃
中培24 - 48 h
挑选出在滤纸培养基上生长良
并进一步在
PDA 基上
面接于种培养2 - 4 d
4
箱冷藏
1. 3 CMC-Na 水解圈测定实验
将初筛菌株接种至 CMC-Na 平板培养基
2 - 5 d
0. 1% 的刚果红水溶液浸染 30 min
1 mol / L NaCl 水溶液脱色 1 h
测菌落直
dcm和水解圈直径Dcm
DP表示水解
DP=D / d2
1. 4 滤纸降解实验
初筛
28摇床培养 5 d 备菌40 mL 的赫奇逊氏
无机养基1 × 6 cm
1 mL
液进 为避免由于震荡造成滤纸断
并满足菌株生长所需的有氧条件
本实验采用的
床转70 r / mim 培养 8 d
据滤断裂
度判+为滤纸边缘膨胀+ +
滤纸+++为滤纸不定形
+ + + + 为成团糊状+++++半清
1. 5 秸秆失重的测定
接种筛选菌株到液体种子培养基中制备菌液
接种 1 mL 制备好的菌液到含有 2% 秸秆木质纤维
素的液体发酵培养基中
行恒震荡
在培养
10 d
滤纸
80℃ 烘干称
用减重法计算出麦秸失重率
1. 6 秆分率的
用王 4的方法进行纤维素
半纤维
质素纤维素的分解率根据下式
对照样品纤维素含量 ×样品重量-
纤维
×残体重量/对照样品纤维素含量 ×样品重
× 100 %
半纤维素和木质素的分解率的计算方法除了将
纤维素含量进行相应的替换
示进行计算
1. 7 纤维素酶活测定
纤维素粗酶液的制备种环PDA
的新鲜菌丝于液体种子培养基中28
170 r / min 培养 60 h
用血球计数板在显微镜下观察
孢子的生长情况
1% 108个孢的接种量到
300 mL产酶培养基中28170 r / min
24 h 取样测定纤维素的酶活力
将培养好的
液体发酵产酶培养基先用两层纱布过滤
滤液再于
410000 × g 10 min
取上清液即为制备的粗
酶活 FPase的测定5
0. 5 mL
加入到含有 50 mg
纸和 1. 5 mL 0. 05 mol / L pH5. 0 柠檬
具塞刻度试管50水浴中保温1 h
立即按 DNS
测定还原糖含量
外切酶活exo-1 4-
β-D-glucanaseCBH /Cex
6适当稀释后的酶液 0. 5 mL
加入到含有
50 mg 脱脂棉和 1. 5 mL 0. 05 mo l /L p H5. 0 柠檬酸
冲液具塞50水浴中保温 1 h
DNS 还原含量
内切酶活endo-14-
β-D-glucanaseEG / Cen
的测7取适当稀释后的酶液 0. 5 mL
加入到
1. 5 mL 1% CMC 柠檬酸缓冲液的具塞刻度试
50℃ 水浴中保温 30 min
DNS 法测定还
178
Hongyuan Wang et al. / Acta Microbiologica S inica 2010 50 7
糖含
β-
萄糖β-1 4-glucosidase
β-Gase
的测定8取适当稀释后的酶液 0. 5 mL
1. 5 mL 1 % 冲液
50 水浴中保温 30 min
立即按 DNS
糖含量
上酶力单U / mL定义为mL 酶液在
上述反应条件下在 1 min 内使底物降解生成 1μmol
葡萄糖所需的酶量酶活力的转换公式如下
酶活力U / mL=
萄糖mg×酶液定容总体积mL× 5. 56
反应液中酶液加入量mL×时间min
5. 56 1 mg μmol 1 000 /180 = 5. 56
1. 8 真菌菌落形态及生理生化测定
观察菌落和菌种形态特征
并参照
和中国真菌志第三十五卷进行菌种鉴定
1. 9 株的 ITS rDNA 鉴定
取真 DNA 18 S rDNA
5. 8S rDNA 的保PCR 引物ITS1:(5′-
TCCGTAGGGAACCTGCGG-3ITS25 ′-GCTGCGT
TCTTCATCGATGC-3 PCR 50 μL
94 5 min94℃ 30 s57 50 s72
50 s30 72℃ 10 min
PCR 扩增产物测序后
DNA
GenBank
Blast 程序与数据库中的所有序列进
比较MEGA4. 1
1W4 的基于 ITS rDNA 序列同源性构建的系统发育树
Fig. 1 Phylogenetic tree of Strain W4 based on ITS rD NA sequences homology.
2结果与分析
2. 1 纤维素分解菌的初筛
挑取片上现孔部位
PDA
养基行分
最终得到 8株在分离培养基
生长度快
且旺盛的真菌菌株将初筛获得的
8真菌行了 CMC-Na 解圈测定1
1真菌的 CM C-Na 水解情况
Table 1 CMC-Na hydrolytic ability of strains
Strain Dp value Strain Dp value
W3 6. 54 a 98DC 1. 53 c
W4 7. 29 a 109 DC 1. 73 c
W7 3. 23 b 98MJ 2. 91 b
W9 1. 34 c 109 MJ 1. 76 c
显著性 P = 0. 01
对初筛获得的 8纯培真菌株进滤纸
解实
研究其纤维素降解能力在为时 8 d
滤纸降解实验中有 3真菌示出显的降解
本文6 d 后的滤纸降
效果2
2菌株培养 6 d 的滤纸降解效果
Table 2 Disintegration results of filter paper scrip with
isolates after culturing 6 d
Strain W3 W4 98MJ
Disaggregation degree + + + + + + + + + + + + + +
2. 2 维素解菌的鉴
根据秸秆降解实验和酶活力测定实验1. 6
1. 7
W4 降解秸秆木质纤维素的能力最
具有深入开展应用研究的潜力
因此利用菌落形
ITS 序列分析对菌株 W4 进行了菌株的鉴定
果表
W4 的菌落开展
表层着生一
层暗绿色分生孢子粉
分生孢子梗光滑
不对称分支 3 - 6
排列紧
其顶端着生 5 - 8 个短小的瓶状小梗8. 7
10. 6 μm × 3. 0 μm
呈椭圆形
部分变
球形
3. 1 - 3. 5 μm
排成纠结的链
将扩增并验证得到的片段测
DNAMAN
件校
578 bp 的核苷酸序列
W4 株的 ITS 序列在 NCBI 网站上进行同源性比
发现该序列与青霉菌的序列同源性 > 99 %
MEGA4. 1 Neighbor-Joining 进行系统发育树的构
果如1
距离W4
离最结合形态观察
真菌鉴定手册
278
王洪媛等三株高效秸秆纤维素降解真菌的筛选及其降解效果. /微生物学报201050 7
国真-
青霉属及其相关有性型
步确W4
张青Penicillium expansum
W3 PDA 基上
色透明
落伸
铺满平板后菌落逐渐增厚
棉絮
时产量孢
显微镜下观察菌丝白色
透明
有分生孢子头
半透明无隔
初步鉴定其为木霉Trichoderma sp.
98MJ PDA
菌落开
绒状
表层着生一层暗绿色分生孢子粉
菌株生
后期面观分生孢子梗无色
称分支
列紧
其顶端着生 6 - 10 个短小的瓶
分生孢子着生于与瓶状小梗上
状小大小
13. 0 ± 5. 6 μm × 3. 5 ± 0. 7 μm
分生孢子链集成圆
椭圆形
光滑无色4. 7 ±
1. 3 μm × 3. 5 ± 0. 6 μm98MJ 菌株属于
青霉属中的草酸青霉Penicillium oxalicum
2. 3 秸秆降解情况
根据对 CMC-Na 的水解结果和滤纸的降解效
选择真菌 W3W4 98MJ 步研
维素降解效果实验分别对这 3株菌在培养 5 d
10 d 秸秆的重量
和各组分的含量以及秸秆的失重率和各组分的降解
率分别在表 32中列出
3菌株降解 10 天后秸秆各组分的含量
Table 3 Contents of cellulosehemicellulose and lignin of straw after being degraded 10 d
Time Strain Weight of straw / g Content of cellulose % Content of hemicellulose % Content of lignin %
0 day CK 1. 000 d 39. 57 b 34. 83 c 24. 77 b
W3 0. 720 d 53. 22 d 22. 64 b 23. 50 ab
5 day W4 0. 744 d 51. 72 d 17. 47 a 22. 31 ab
98MJ 0. 732 d 53. 47 d 19. 95 ab 20. 63 a
W3 0. 547 b 41. 86 c 21. 57 b 31. 99 c
10 day W4 0. 437 a 37. 07 a 16. 93 a 37. 53 d
98MJ 0. 668 c 54. 49 d 17. 22 a 32. 49 c
P = 0. 01
2菌株降解 10 天后秸秆组分的变化情况
Fig. 2 Chan ges of straw component after being degraded 10 d by
strains.
5 d 398MJW3 W4
秆木纤维都有
但差异性不大
秸秆失
重率26. 8 % 28. 0% 25. 6 % 5 d
纤维中半
98MJ
W3 W4 对半纤维素的相对降解率分别为
58. 08% 53. 20 % 62. 68 % 10 d
纤维素
相对
其降解率分别为 42. 13%
8. 01 % 59. 06% 10 d 3株真菌菌株
98MJW3 W4 秸秆
别为 33. 2% 45. 3% 56. 3%
W4
其降解秸秆木质纤维素的能力最高
纤维素
半纤维
和木质素的分解率分别为 59. 06% 78. 75%
33. 79%
2. 4 维素活测结果
定菌98MJW3W4
外纤
其中包括外切葡聚糖酶CBH /
Cex
内切葡聚糖酶EG / Cen
β-
葡萄糖苷酶β-
Gase9三种纤维素酶以及反映纤维素酶系总效率
的滤纸酶活FPase
结果表明3
而且其外切葡聚糖酶活5. 78 - 49. 75 U /mL
β-
萄糖酶活5. 48 33. 29 U / mL普遍高于
切葡2. 89 - 14. 25 U / mL和滤纸酶活
2. 95 - 21. 27 U / mL43株真菌的胞外纤
素酶间具
W4 14. 25 - 49. 75
U / mL>W34. 17 - 9. 46 U / mL>98MJ
2. 89 - 5. 78 U / mL
其中菌株 W4 的纤维素酶活
这与秸秆纤维素降解实验的结果一致
378
Hongyuan Wang et al. / Acta Microbiologica S inica 2010 50 7
4纤维素酶活力测定结果
Table 4 Enzyme activity results of strains
Strain W3 W4 98 MJ
Enzyme
activity
U / mL
FPase 4. 17 b 21. 27 c 2. 95 a
EG 4. 26 b 14. 25 c 2. 89 a
CBH 9. 46 b 49. 75 c 5. 78 a
β-Gase 8. 68 b 33. 29 c 5. 48 a
P = 0. 01
木质纤维素降解酶的研究与应用主要集
于产量大
酶系组成比较齐全的木霉
白腐菌
青霉菌株10而与白腐
青霉菌又具有
培养生长
青霉具有很高的商
业价值和潜力应用于木质纤维素的降解已报道产
木质纤维素降解酶系的青霉菌株有 19 种之多
Penicillium . decumbens
Penicillium janthinellum 和绳状青霉Penicillium
funiculosum 等菌产酶力最11也有关于
草酸青霉产酶的报告
但酶活力不高12 - 13
扩张青霉 W4 是本研究获得的纤维素酶活力最强
的菌
14. 25 49. 75 U / mL
高 于 许 多 已 报 道 的 菌 株14 18 马旭光
14 过航空诱变获得的纤维素降解菌 ZM-8
的纤维素酶活力在1. 84 - 2 0. 14 U / mLAham ed
15 研究表明工业生产中常用的纤维素酶生产菌
里氏RUT-C30 产生的 FPase 5. 02 U / mL
CMCase 4. 2 U / mL16获得的高
纤维 L-06
3. 14 - 25. 31 U /mL之间17 获得的包括
腐真
绿色木霉在内的7种具有降解纤维材料能
力的
0. 28 - 12. 54 U / mL
有研1 8
2. 5 g /L 业纤
Celluzyme FPase 9. 20 U /L扩张青霉 W4
一株十分具有研究开发潜力的纤维素酶生产
3
1筛选到 3有较
初步98MJ 为草酸青霉W3 为木霉W4
扩张
21株具
张青W4
10 d 内秸秆降解率为 56. 3%
半 纤 维 素 和 木 质 素 的 分 解 率 为 59. 06%
78. 75% 33. 79%
14. 25
49. 75 U / mL 之间
是一株十分具有研究开发潜力的
纤维素酶生产菌株
3秸秆纤维素分解率和胞外纤维素酶活力能
够比较准确的反映出菌株的秸秆木质纤维素降解能
谢 本文研究
龚明波博士和殷中伟硕
士在菌株筛选
多帮
在此特表感谢
参考文献
1Adsul MGBastawde KB Varma AJGokhale DV.
Strain improvement of Penicillium janthinellum NCIM
1171 for increased cellulase production. Bioresource
Technology2007 98 714671473 .
2Magalhaes POFerraz AMilagres AFM. Enzymatic
properties of two beta-glucosidases from Ceriporiopsis
subvermispora produced in biopulping conditions.
Journal of Applied M icrobiolog y2006101480-486.
3Petr Baldrian VVK. Degradation of cellulose by
basidiomycetous fungi. FEMS M icrobiology Review s
2008323501 -521.
4王玉万徐文玉.木质纤维素固体基质发酵物中半纤
纤维素和木质素的定量分析程序.微生物学通
Microbiology 1987,( 282-84.
5李宪臻高培基.纤维素酶测定方法评述.
微 生 物 Indus trical Micr obiolo gy . 1994 24 4
27-32.
6Ghose TK. Measurement of cellulose activities. Pure and
Applied Chemistry198759 257 -268.
7Horikoshi K Nakao MKurono YSashihara N.
Cellulase of an alkalophilic Bacillus strain isolated from
soil. Canadian Journal of M icrobiology198430774-
779 .
8Christakopoulos PGoodenough PWKekos D.
Purification and characterization of an extracellular β-
glucosidase with transglycosylation and exo-glucosidase
activites from Fusarium oxysporum.European Journal of
Biochemistry1994224 378-385 .
9Kansoh ALEssam SAZeinat AN. Biodegradation and
utilization of bagasse with Trichoderma reesie. Polymer
Degradation and Stability199963 2273-278 .
10Jrgensen H MrkebergAKrogh KBROlsson L.
Production of cellulases and hemicellulases by three
Penicillium speciesEffect of substrate and evaluation of
cellulose adsorption by capillary electrophoresis. E nzym e
and M icrobialogy Technology 20053642 -48.
478
王洪媛等三株高效秸秆纤维素降解真菌的筛选及其降解效果. /微生物学报201050 7
11
曲音波
刘自勇.青霉木质纤维素降解酶系
研究进展.应用与环境生物学报Chinese Journal of
Applied and E nvironmental Biology2007 13 5) :
736 -740.
12王宝维
张名爱
姜晓霞
王巧莉
.鹅源草酸青霉 F67 产纤维素酶培养条件的优化.
农 业 大 学学 报 Journa l of Shenyang A gricultural
University 200940 147 -52.
13刘果段承杰
冯家勋.两株纤维素降
解真菌的分离鉴定及其产纤维素酶酶学性质的初步
.广西农业科学Guangxi Agricultural Sciences
2008 394425-428.
14张宗舟蔺海明.黑曲霉产高酶活纤维素酶
变 株 ZM-8 的筛选.饲料工业Fee d Ind ustry
2006 272411-13 .
15Ahamed A Vermette P. Culture-based strategies to
enhance cellulase enzyme production from Trichoderma
reesei RUT-C30 in bioreactor culture conditions.
Biochemical Engineering Journal200840 3399-
407 .
16淑霞龙传南.纤维素降解菌 L-06 的筛选
定及 .生物工程学报Chinese
Journal of Biotechnology2008 2406 1112-1116.
17张力韩大勇.新型秸秆分解菌的筛选和酶
研 究.中兽医医药杂志Journal of Trad itional
Chinese Veterinary Medicine2008,(0315 -17.
18Rodriguez CHiligsmann S Ongena M. Development of
an enzymatic assay for the determination of cellulose
bioavailability in municipal solid waste. Micro bial
Ecology200516 5415-422.
Screening of three straw-cellulose degrading microorganism
Hongyuan WangBingquan Fan*
Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081
China
Abstract:[ObjectiveThe aim of this study was to screen straw-cellulose degrading microorganisms and to investigate
their degradation ability of straw -cellulose. Meth ods The methods used to screen the high effect straw-cellulose
degrading microorganism included the traditional isolation methods of straw-cellulose degrading microorganism such as
holes observation method on filter paper sheetdisintegration test of filter paper scriphydrolysis spot diameter
measurement method of CMC-Naweight lose assay method of strawmeasurement method of cellulose decomposition rate
measurement method of extracellular enzyme activity. ResultsWe isolated 3 fungi with cellulose degrading abilityof
which 98 MJ was identified as Penicillium oxalicumW3 as Trichoderma sp. and W4 as Penicillium expansum. Strain W4
possessed high straw -cellulose degrading ability with straw-cellulose degrading rate of 56. 3% cellulose 59. 06%
hemicellulose 78. 75% and lignin 33. 79 % in 10 days. Co nclusion Strain W4 was a cellulase-producing strain with
broad development potential.
KeywordsStraw-cellulosedegrading microorganismscreeningcellulase
文责张晓丽
Supporded by The 11th Five Years Key Programs for Science and Technology Development of China 2007BAD89 B13 and the National Programs for
High Technology Research and Development of China2006AA10Z426
*Corresponding author. Tel+ 86 -1 0-8210 6212 E-mail Bqfan@ caas. ac. cn
Received3 D ecember 2009 / Revised 19 April 2010
578
... Paecilomyces variotii is a fungal species commonly found in storage areas of libraries and archives [37]. Penicillium chrysogenum and International Journal of Microbiology 5 Alternaria alternata are known as paper biodeteriogens [23] and Penicillium expansum was found capable of degrading straw-cellulose [38]. ...
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