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米曲霉木聚糖酶生产菌的理性选育及发酵优化 总被引:2,自引:1,他引:1
目的:米曲霉木聚糖酶生产菌的理性选育及发酵优化。方法:以米曲霉FS018为出发菌株,采用紫外和激光诱变先后处理3代,以抗高浓度葡萄糖阻遏效应为筛选模型获得一株高产木聚糖酶菌株FST036,并对该菌株的发酵培养基进行了初步优化。结果:突变株FST036产酶水平可达4200.57U/mL,产酶水平比出发菌株提高了24%。对该菌株的发酵培养基初步优化结果表明:培养基的最适氮源为牛肉膏;最适碳源为麸皮与玉米芯组合,总浓度为4%。二者最适比例为7:3;对该菌株的发酵条件初步优化结果表明:最适接种量1%,初始pH6.78,250mL三角瓶装液量为45mL,培养72h酶活可达5404.24U/mL。结论:反复多次诱变处理,并结合抗高浓度葡萄糖阻遏效应作为一种理性筛选模型,为通过诱变育种来获得曲霉木聚糖酶高产菌株提供了一条有效的途径。 相似文献
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木聚糖酶高产菌株的鉴定及产酶条件的优化 总被引:1,自引:0,他引:1
目的:通过了解木聚糖酶高产菌株A79的遗传背景.并优化其产木聚糖酶的液体发酵条件,为下一步工业化生产和木聚糖酶制剂的研制奠定基础.方法:通过形态观察和18S rDNA基因的分子系统进化分析,对菌株A79进行鉴定;通过单因素和均匀设计试验,优化其产胞外木聚糖酶的液体发酵条件.结果:通过对18S rDNA基因的分子系统进化分析,菌株A79被鉴定为黑曲霉(Asperillus niger A79).其最佳产酶培养基为:玉米芯5.0%,麸皮0.5%.纤维物质1.O%,玉米浆1.1%.(NH4)2SO40.8%,蛋白胨0.8%,CaCO3 0.5%,KH2PO4 0.23%,MgSO4,·7H2O 0.08%,微量元素(MaIldels)0.08%,pH自然.最佳发酵条件为:接种量5%(2.0×107),28℃、250r/min振荡培养96h.结论:经优化培养,酶活力由前期的50 000u/ml提高到90000u/ml,增加了近50%. 相似文献
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YANG Zhang-ping CAI Shao-li KE Chong-rong HUANG Ping LIU Xiao-lin YU Qing-mei ZHUANG Xiu-hong CHEN Lin LIN Guo-yan HUANG Jian-zhong 《工业微生物》2012,42(3)
通过对木聚糖酶高产菌株EIM-30基于形态学和18S rDNA序列的系统发育进化分析,鉴定为里氏木霉Trichoderma reesei.在单因子实验确定EIM-30产木聚糖酶的最适碳源和氮源的基础上,通过Plackett-Burman实验对影响其产酶的相关因素进行评估并筛选出3个显著效应因子,然后应用最陡爬坡实验和响应面分析确定最适产酶培养基配方为:酵母浸膏1.50%,蛋白胨1.00%,NaCl 0.50%,PPG-2000 0.10%,MgSO4 1.20%,CaCl2 0.18%,(NH4)2 SO4 0.45%,甘油4.18%,乳糖3.05%,K2HPO41.59%.优化后Trichoderma reesei EIM-30的液体发酵产木聚糖酶的活力可达9.857×105 U/mL,较优化前提高1.98倍. 相似文献
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黑曲霉X-1产木聚糖酶液体发酵工艺研究 总被引:1,自引:0,他引:1
目的:提高黑曲霉X-1菌株液体发酵木聚糖酶的产量.方法:采用单因素和正交试验对黑曲霉X-1菌株产木聚糖酶液体发酵培养基和培养条件进行了优化.结果:通过正交试验找出最大影响因素为玉米芯和葡萄糖的供应,优化后的最佳培养基和培养条件为:玉米芯粉3%,葡萄糖0.5%,蛋白胨1%,KH2PO4 0.5%,MgSO4·7HO 0.1%,Tween-80 0.‰,pH 6.5,30℃、200r/min摇瓶培养120h.结论:黑曲霉X-1菌株在优化后的培养基和培养条件下,木聚糖酶活力高达1 630.78U,比优化前木聚糖酶活力(724.63U)提高了125.05%. 相似文献
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具有高木二糖形成活力的木聚糖酶生产菌株的筛选与产酶培养基的优化 总被引:15,自引:0,他引:15
从土样中筛选出一株产木聚糖酶的青霉,该青霉所产木降糖酶具有很高的木二糖形成活力,经鉴定为顶青霉,其木聚糖酶的合成与分泌受木聚糖等木糖苷类物质的诱导,麸皮对其木聚糖酶的合成也有促进作用,优化产酶液体培养主要成分的配比为:麸皮:玉米芯木聚糖:玉米芯粉;蛋白胨(或尿素)=1:1:1:0.6(0.4),摇瓶96h达到最大酶活,最高木聚糖酶活达到289.3U/ml,该菌所产木聚糖酶的最适作用条件为45-50度,PH4.4,在PH4.4-8.0范围内稳定。 相似文献
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利用农业废弃物生产嗜热真菌(T.1anuginosus)耐热木聚糖酶的固体发酵研究 总被引:5,自引:1,他引:4
研究了嗜热真菌(Thermomyces lanuginosus CBS288.54-M18)生产木聚糖酶的碳氮源组成、料水比、培养基初始pH值、发酵温度及接种量等的影响。结果表明,以麦麸和玉米芯粉(8:2)作为复合碳源,酵母膏和胰蛋白胨(1:1)作为复合氮源时,菌株所产的木聚糖酶量相比未优化碳氮源的培养基提高幅度高达200%。其最佳产酶的料水比为1:3,培养基初始pH7.0为最适。菌株在50℃条件下发酵5d,能够得到活力高达15023U/g干基碳源的木聚糖酶制剂,且该酶制剂不合纤维素酶和蛋白酶活性。 相似文献
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木聚糖酶生产菌株的筛选及产酶条件的优化 总被引:6,自引:0,他引:6
以甘蔗渣半纤维素为碳源,从垃圾场土壤中分离到6株分解半纤维素的菌株。通过固态发酵的木聚糖酶活力比较筛选到1株木聚糖酶活力较高的菌株。该菌株18S rDNA序列与曲霉(Aspergillus sp.)的同源性达97%,根据对菌株形态学分析和18S rDNA序列分析的结果,将该菌株鉴定为曲霉HQ3。HQ3的最佳产酶条件为:甘蔗渣:麸皮为7:3(W/W),固液比为1:4(W/W),尿素0.4 %,pH7.0,温度30℃,发酵产酶时间4 d。在最佳产酶条件下,其木聚糖酶活最高可达3421U/g干曲。 相似文献
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Nam Keun Lee 《Biotechnology and Bioprocess Engineering》2018,23(1):55-63
Recombinant xylanase (rPcXynC) from Pichia pastoris was produced on large-scale by optimizing production-medium composition using statistical experimental methods. Production medium was optimized through the use of statistical methods such as one factor at a time (OFAT), Plackett-Burman design, fractional factorial design (FFD), steepest ascent method (SAM), and response surface methodology (RSM). The optimum medium composition was established to be (g/L); wheat bran 11.62, yeast extract 30, Tween 60.5, DL-β-Phenylalanine 0.5, Thiamine 0.5, FeSO4 0.01, KH2PO4 0.66, and KHSO4 0.09. The optimum medium composition yielded 3,051 mU/mL of xylanase activity which was three times higher than that obtained from the initial medium composition. Finally, fermentation conditions were examined using the optimized production medium in a laboratory bioreactor. The optimal fermentation conditions were found to be 25ºC, pH 6, 170 rpm and 1 vvm with intermittent feeding of methanol (67.5 mL) and the xylanase activity was 3,683 mU/mL. In repeated-batch fermentation using optimized production medium and fermentation condition, the xylanase activity was 3,680 mU/mL at the first cycle of 96 h harvesting time using 90% of the culture solution. The activity was similarly maintained until the last cycle of 264 h. 相似文献
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Ganoderma lucidum, a white rot fungus, was exploited for its potentials to produce xylanase employing shake and solid-state culture conditions. Different culture conditions such as pH, temperature, carbon and nitrogen requirements for its growth and production of xylanase were optimized. The culture media pH 6.0-7.0 and temperatures 30 degrees-35 degrees C significantly promoted the growth as well as xylanase secretion into the media. Xylan and peptone were found to be the suitable carbon and nitrogen sources. Among the different agrowastes used, wheat bran was found to be the best substrate for the test fungus for the production of xylanase than sugarcane bagasse and rice bran in solid-state fermentation. 相似文献
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S. Prakash Y. Veeranagouda L. Kyoung K. Sreeramulu 《World journal of microbiology & biotechnology》2009,25(2):197-204
A halophilic and alkali-tolerant Chromohalobacter sp. TPSV 101 with an ability to produce extracellular halophilic, alkali-tolerant and moderately thermostable xylanase was
isolated from solar salterns. Identification of the bacterium was done based upon biochemical tests and 16S rRNA sequence.
The culture conditions for higher xylanase production were optimized with respect to NaCl, pH, temperature, substrates and
metal ions and additives. Maximum xylanase production was achieved in the medium with 20% NaCl, pH-9.0 at 40°C supplemented
with 1% (w/v) sugarcane bagasse and 0.5% feather hydrolysate as carbon and nitrogen sources. Sugarcane bagasse (250 U/ml)
and wheat bran (190 U/ml) were the best inducer of xylanase when used as carbon source as compared to xylan (61 U/ml). The
xylanase that was partially purified by protein concentrator had a molecular mass of 15 kDa approximately. The xylanase from
Chromohalobacter sp. TPSV 101 was active at pH 9.0 and required 20% NaCl for optimal xylanolytic activity and was active over a broad range
of temperature 40–80°C with 65°C as optimum. The early stage hydrolysis products of sugarcane bagasse were xylose and xylobiose,
after longer periods of incubation only xylose was detected. 相似文献
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Thermoactinomyces thalophilus produced cellulase free extracellular endo-1,4-beta-xylanase (EC 3.2.1.8) at 50 degrees C and pH 8.5. Maximum xylanase production was achieved in fermentation medium using birchwood xylan as substrate after 96 h of growth at 50 degrees C. Other agricultural substrates such as wheat bran, wheat straw, sugarcane bagasse and cornstover produced less xylanase. The crude enzyme preparation from mutant T. thalophilus P2 grown under optimised fermentation conditions showed no cellulase contamination and maximum xylanase activity of 42 U/ml at 65%deg;C and pH 8.5-9.0. This enzyme with initial xylanase activity of 42 U/ml was found thermostable up to 65 degrees C and retaining 50% of its activity after its incubation for 125 min at 65 degrees C. 相似文献
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Gupta Saurabh Kuhad R.C. Bhushan Bharat Hoondal G.S. 《World journal of microbiology & biotechnology》2001,17(1):5-8
The production of an alkali-stable xylanase, with dual pH optima, from haloalkalophilic Staphylococcus sp. SG-13 has been enhanced using agro-residues in submerged fermentation and a biphasic growth system. The agro-residues such as wheat bran, sugarcane bagasse, corncobs and poplar wood when used as sole carbon source, improved the xylanase yield by five-fold as compared to xylose and xylan. Staphylococcus sp. SG-13 also produced equally good amounts of xylanase when grown simply in deionized water (pH 8.0) supplemented with agro-residues as sole carbon source. In the biphasic growth system (lower layer containing agricultural residue set in agar medium with liquid medium above it), the prime substrate, wheat bran (1% w/v), resulted in maximum xylanase production of 4525 U l–1 (pH 7.5) and 4540 U l–1 (pH 9.2) at an agar: broth ratio of 4.0 after 48 h of incubation at 37 °C under static conditions. In general, the cost-effective agro-residues were found to be more suitable inducers for xylanase production over expensive substrates like xylan. 相似文献
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Facchini FD Vici AC Reis VR Jorge JA Terenzi HF Reis RA Polizeli Mde L 《Bioprocess and biosystems engineering》2011,34(3):347-355
Solid-state fermentation obtained from different and low-cost carbon sources was evaluated to endocellulases and endoxylanases
production by Aspergillus japonicus C03. Regarding the enzymatic production the highest levels were observed at 30 °C, using soy bran added to crushed corncob
or wheat bran added to sugarcane bagasse, humidified with salt solutions, and incubated for 3 days (xylanase) or 6 days (cellulase)
with 70% relative humidity. Peptone improved the xylanase and cellulase activities in 12 and 29%, respectively. The optimum
temperature corresponded to 60 °C and 50–55 °C for xylanase and cellulase, respectively, both having 4.0 as optimum pH. Xylanase
was fully stable up to 40 °C, which is close to the rumen temperature. The enzymes were stable in pH 4.0–7.0. Cu++ and Mn++ increased xylanase and cellulase activities by 10 and 64%, respectively. A. japonicus C03 xylanase was greatly stable in goat rumen fluid for 4 h during in vivo and in vitro experiments. 相似文献
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Bingying Ye Ting Xue Shichao Ye Shengyan Xu Weiyan Li Jihua Lu Fang Wei Wenjin He Youqiang Chen 《生物学前沿》2013,8(6):611-617
To improve the fermentation yield of xylanase by optimizing the fermentation conditions for strain Xw2, a Plackett-Burman design was used to evaluate the effects of eight variables on xylanase production by strain Xw2. The steepest ascent (descent) method was used to approach the optimal response surface experimental area. The optimal fermentation conditions were obtained by central composite design and response surface analysis. The results showed that the composition of the optimal fermentation medium was corn cob + 1.5% wheat bran (1:1), 0.04% MnSO4, 0.04% K2HPO4. 3H2O, and an inoculum size of 6% in 50 mL liquid volume (pH = 6.0). The optimal culture conditions were 28oc at 150 r/min for 54.23 h. The results of this study can serve as the basis for the industrial production and application of xylanase. 相似文献