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1.
在250ml三角烧瓶中进行Zymobacter palmae菌株发酵不同浓度的甘露醇生产乙醇的实验。实验先以浓度为20.0g/L、40.0g/L、60.0g/L、80.0g/L的甘露醇进行发酵实验确定出最适培养基组分,然后通过正交试验确定出最佳发酵条件。结果表明,最适发酵培养基为:甘露醇20.0g/L,酵母膏0.5g/L,MgSO4.7H2O 0.1g/L,KH2PO42.0g/L,K2HPO47.0g/L,(NH4)2SO4 1.0g/L,pH值6.0;最佳发酵条件为:摇床转速150r/min,温度28℃,发酵液体积150ml。在最佳发酵条件下,乙醇的最大产量为0.429g乙醇/g甘露醇。  相似文献   

2.
为进一步探索高产褐藻胶裂解酶菌株,促进其工业化应用,以褐藻酸钠为唯一碳源筛选培养基,从鲍鱼内脏中筛选出一株高产褐藻胶裂解酶菌株B4,通过形态学观察和系统发育分析,鉴定为弧菌属细菌Vibrio sp.B4。通过单因素实验对B4菌株的发酵条件和发酵培养基进行优化,获得发酵培养基的最适碳源为褐藻酸钠10g/L,最适氮源为(NH4)2SO410g/L,最适发酵条件为温度30℃,接种量1%,培养基初始pH 6.0。在单因素实验的基础上,通过Plackett-Burman(PB)筛选出3个影响产酶活力的显著因素:(NH4)2SO4浓度、pH、接种量。通过响应面进一步分析优化,得到最佳的发酵培养基为褐藻酸钠10g/L,(NH_4)_2SO_4 10.91g/L,NaCl 10g/L,KH_2PO_4 1g/L,MgSO4·7H2O 0.5g/L,CaCl_2 0.2g/L,FeSO_4·7H_2O 0.02g/L,最佳发酵条件为温度30℃,接种量1.1%,起始pH 6.07。在最佳培养条件下,褐藻胶裂解酶活力可达19.09U/mL,比基础培养条件下提高了3.67倍。该菌经过产酶发酵条件的优化,酶活力得到较大幅度的提高,且其发酵产酶时间短,可为褐藻胶裂解酶的进一步研究应用提供参考。  相似文献   

3.
刺糖菌素是由多刺糖多孢菌(Saccharopolyspora spinosa)产生的次级代谢产物,是一种具有触杀及摄食毒性的广谱杀虫剂.通过单因素实验和正交实验对菌株Saccharopolyspora spinosa CT205发酵产刺糖菌素的发酵条件进行了优化.结果表明:该菌产刺糖菌素的发酵培养基添加可溶性淀粉、黄豆饼粉、Na2B4O7和CoCl2可提高刺糖菌素的发酵单位,且得出发酵培养基的初始pH、摇瓶装量和接种量分别以7.0,30 mL/250 mL和10%为最佳.正交实验分析得到最优的发酵培养基为葡萄糖3.0%、可溶性淀粉3.0%、棉籽粉1.0%、黄豆饼粉1.0%、CoCl20.1 mg/L、NaB4 O7 0.1 mg/L.优化之后刺糖菌素的发酵单位达到了90.21μg/mL,比优化前提高了78.5%.  相似文献   

4.
研究了红曲霉产多糖的液态发酵条件,得出优化后的培养基组成为:蔗糖45 g/L,酵母粉4.5 g/L,KH2PO4·3H2O 3.5 g/L,MgSO4·7H2O 0.85 g/L.通过单因素实验和正交试验,得到红曲霉N产多糖的优化发酵工艺条件为:种龄30 h,接种量7.5%,发酵培养基初始pH 5.75,装液量162.5mL/1 000 mL三角瓶,发酵时间84 h.在此条件下,红曲霉液态发酵的多糖质量浓度达999.8 mg/L,比优化前的684.2 mg/L提高46.1%。  相似文献   

5.
采用单因子和正交实验相结合的方法,在摇床水平对柑橘内生菌YS4产生抑菌活性物质的发酵培养基和发酵条件进行研究.结果表明,最佳发酵培养基配方为:PDA100 g/L,糖蜜15 g/L,NH4NO31 g/L,K2HPO40.15 g/L,FeSO4 0.2 g/L,Ca-CO3浓度8%,最佳发酵条件为:温度30℃,初始PH6.5,接种量10%,发酵时间28h,摇床转速150r/min.  相似文献   

6.
白阿魏菇深层发酵工艺的研究   总被引:3,自引:0,他引:3  
用单因子实验、正交实验,检测白阿魏菇深层发酵指数,结果为:摇瓶发酵的最佳条件为温度25℃,装液量为三角瓶体积的1/5,培养基起始pH值5.5,接种量10%,大号玻璃珠12个/瓶 通过单因子和正交实验可知,菌丝体生长的最佳碳源为土豆汁;发酵罐最佳培养基配方为葡萄糖0.5%,蔗糖0.5%,玉米粉5%,麸皮4%,蛋白胨0.2%,KH2PO40.1%,MgSO4·7H2O0.05%,羧甲基纤维素钠0.5%,VB1微量;发酵罐发酵时间为48h  相似文献   

7.
纤溶酶高产菌株筛选及其液体发酵条件研究   总被引:9,自引:6,他引:3  
研究实验室自主分离的2株纤溶酶高产菌株发酵条件,采用4因素、3水平的正交试验设计方法对液体发酵培养基的碳源、氮源、无机盐进行了优化,并对培养基初始pH、发酵时间、发酵温度对产酶量的影响进行了测定.结果表明:菌株1液体发酵合适的产酶培养基配方为大豆粉的质量分数为6%,葡萄糖2%,CaCl2 0.06%,MgSO4 0.07%;菌株2液体发酵合适的产酶培养基配方为大豆粉的质量分数为6%,玉米淀粉2%,CaCl2 0.06%,MgSO4 0.07%.培养基初始pH均为6.5时酶活性最高;发酵温度均以38℃最好;而菌株1和菌株2的适宜发酵时间分别为48~84 h和60~84 h.在优化条件下,菌株1、菌株2液体发酵最高酶活分别为306.46 IU/mL和319.76 IU/mL。  相似文献   

8.
对能转化阿魏酸生成香兰素的一株桑肠杆菌VL4-3的发酵培养基、发酵培养条件、种子培养基和种子培养条件进行优化.确定了液体发酵的最佳培养基:麸皮10g/L,豆粕1g/L,氯化钠0.5g/L,硫酸亚铁0.5g/L,pH=8;最佳发酵培养条件:接种量10%,摇瓶装液量10%,阿魏酸最大加入量10g/L,37℃,100r/min,避光培养12d;最佳种子培养基:牛肉膏蛋白胨培养基;最佳种子培养条件:25℃,100r/min,24h.在上述优化发酵条件下,发酵液中香兰素最大浓度为2 262.43mg/L,最大转化率为28.87%.  相似文献   

9.
采用单因子试验和正交试验,对菌株槭菌刺孢(Mycocentrospore acerina)的发酵培养基进行优化,得到最佳发酵培养基配方为:蔗糖6%,黄豆粉2.26%,(NH4)2SO40.16%,CaCO30.45%,NaCl 0.19%;最佳发酵条件为20℃,100r/min,起始pH值为7.0,在250mL的三角瓶中加入优化发酵培养基50mL,发酵培养240h;在发酵过程中,不必补加各成分,其原始培养基成分已足够整个发酵过程中产色素的需要.  相似文献   

10.
对黑曲霉HYA4固态发酵生产果胶酶的培养条件进行了研究,固态发酵培养基组分为:250 mL三角瓶中甜菜渣5 g,黄豆粉5 g,NH4H2PO4 0.4%,FeSO4·7H2O 0.05%.料水比1:2.采用此优化的培养基在培养温度36℃和初始pH自然条件下进行发酵,果胶酶酶活力可达5465.8 U/g(干曲).  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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