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1.
产碱性木聚糖酶芽孢杆菌HSⅠ的筛选及发酵条件研究   总被引:3,自引:0,他引:3  
通过碱性培养基分离到耐碱的芽孢杆菌HSⅠ,研究了碳源,氮源,培养温度,培养基起始pH,培养时间,接种量,通气量,添加物对HSⅠ菌产木聚糖酶的影响。测定出其产酶最佳培养条件;麸皮6%,(NH4)2SO40。2%,NaNO30.4%。蛋白胨0.6%,起始pH为10.5,接种量为5%,250mL三角瓶装液量为50mL。最佳培养温度为37℃,培养时间为96h,其酶活力最高达54IU/mL。  相似文献   

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对绿色木霉接种到啤酒糟固态发酵产纤维素酶的培养基和培养条件进行优化,考察发酵物料起始含水量、发酵时间、起始pH值等发酵条件,以及啤酒糟培养基中添加麸皮、氮源种类对产酶的影响。结果表明,以啤酒糟为发酵基质接种绿色木霉生产纤维素酶是可行的。经单因素和正交试验获得最适固态发酵的培养条件为:起始pH 5~6,培养温度28~30℃,发酵4 d;最佳发酵培养基组合为:麸皮比例30%,培养基起始含水量50%,(NH4)2SO4添加量为2.0%~2.5%。  相似文献   

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杏鲍菇液体培养研究初报   总被引:4,自引:1,他引:3  
采用液体摇瓶培养方法,对杏鲍菇适宜的液体培养基和液全培养条件(适宜温度,摇瓶装量,摇瓶转速,接种量,培养基初始pH等)进行了探讨。结果表明,杏鲍 菇适宜的液体培养基为:葡萄糖3%,蛋白胨0.2%,KH2PO40.05%,MgSO40.05%,pH6.5,适宜的液全培养条件为:培养温度25℃,培养基的初始pH6.5,摇瓶装量100-140ml/500ml,摇瓶转速150r/min,接种量10%,最佳培养时间7d。  相似文献   

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光合细菌最佳生长条件筛选   总被引:1,自引:0,他引:1  
目的:优化光合细菌的最佳培养条件。方法:通过绘制不同的生长曲线研究不同培养基及不同培养条件等理化因素对2株光合细菌(类球红细菌1.2174、沼泽红假单胞菌1.2180)生长的影响。结果:①1.2174最佳条件:培养基(蒸馏水配制的液体富集培养基和固体ATYP);温度(35℃);pH值(8.0和9.0);接种量(培养基/种子液5:1和4:1)。②1.2180最佳条件:培养基(海水配制的ATYP和蒸馏水配制的液体富集培养基);温度(25℃和35℃);pH值(7.0和8.0);接种量(培养基/种子液2∶1和4∶1)③两株菌的光照、氧需求程度、菌群协同和振荡条件相同。结论:通过筛选,蒸馏水配制的液体富集培养基和固体ATYP培养基、35℃、1000lx、pH值8.0、培养基/种子液4∶1、微氧、有菌群协同、振荡可作为二者的通用培养条件。  相似文献   

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[目的]研究筛选得到的低温乳酸菌复合菌系(LAC-1)的最佳培养条件及应用于玉米干秸杆微贮的效果.[方法]通过连续限制性培养的方法,以pH为指标进行低温乳酸菌复合系的筛选;利用单因素试验、Box-Benhnken试验设计和响应面的分析方法对低温乳酸菌复合系的培养条件进行优化.[结果]筛选获得培养液pH下降迅速、变化稳定及接种干玉米秸杆后可降低发酵体系pH、提高发酵饲料感官品质的低温乳酸菌复合菌系LAC-1.培养时间对LAC-1的pH降低速度影响最大,温度次之,接种量影响最小;响应面分析LAC-1最佳的培养条件为培养温度9.5℃、接种量3.3%和培养时间139 h.经过优化,LAC-1培养过程中pH下降到4.0的时间比优化前缩短48 h,乳酸菌数提高了20.5%.LAC-1接种于干玉米秸秆发酵5d时,秸秆发酵体系pH降至4.1;与对照相比,秸秆发酵饲料可散发出甜酸香味,外观质地松散、色泽鲜亮,可溶性碳水化合物含量降低了46.3%,霉菌、恶臭醋酸杆菌和酵母菌数量显著降低,乳酸菌数量提高了33.3%.[结论]接种LAC-1可促进干玉米秸秆低温微贮进程,提高饲料品质.  相似文献   

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浮萍棘尾虫(Stylonychia lemnae)是一种营动物性营养的单细胞真核生物, 是研究细胞学、遗传学问题的重要模式原生动物, 而实现浮萍棘尾虫纯培养是开展棘尾虫生物学研究的重要基础。研究以建立高效棘尾虫无菌纯培养体系为目的, 参考嗜热四膜虫无菌纯培养基, 采用响应面分析方法, 对氮源、碳源和磷酸氢二钾的组分配比进行单因素实验和正交实验, 初步建立用于浮萍棘尾虫无菌培养的培养基, 并分别对培养温度、初始pH、培养液添加量和起始接种密度等培养条件进行了优化。结果表明: 起始接种量为100 cells, 培养基10 mL, 初始pH 7.0, 温度25℃, 静置培养168h, 可获得最大细胞数量约为3.0×103 cells。  相似文献   

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研究地生枝顶孢AT01菌株胞外多糖发酵工艺,主要内容包括碳源、氮源、起始pH及接种量等.AT01胞外多糖的最佳培养基组成白砂糖4%,黄豆粉3%,磷酸氢二钾0.5%,氢氧化钙O.3%,MgSO4·7H2O O.05%,pH自然(6.7).最佳培养条件接种量为1O%,起始pH为6.7,装液量为100mL/250mL.  相似文献   

8.
沈秀荣 《生物技术》2001,11(6):23-25
通过单因子试验统计分析,优化筛选了适于金针菇(Flammulina velatipes)FV908的适宜培养基和摇瓶培养条件,结果表明,其适宜的液体培养基组成为5.0%玉米粉,2.0%麸皮,0.1%KHOP4,0.05%MgSO4*7H2O,10μgVB1/100ml,50μgVB2/100ml;适宜的摇瓶培养条件为培养基的起始pH6.0~7.0,500ml摇瓶装量为150ml,接种量为10%,培养温度25℃,摇床转速为120r/min,菌丝干收率4.1g/100ml.  相似文献   

9.
万古霉素发酵废渣固态发酵生产单细胞蛋白的研究   总被引:1,自引:0,他引:1  
以万古霉素发酵废渣为唯一培养基,对固态发酵生产单细胞蛋白(SCP)进行了研究.经过筛选得到了一株白地霉HCCB 2267,它能以万古霉素发酵废渣为唯一底物生长.通过菌株驯化和培养条件优化,固态发酵产生的SCP可迭9.42×108个/g干重,其粗蛋白含量达47.24%,氨基酸总量从30.60%提高到46.28%.其优化的培养条件是:培养基起始含水量60%,起始pH 5.0~6.0,接种量15%,培养温度28~30℃,培养时间72h等.此外,筛选到的菌株对废渣中残存的菌丝体有降解作用.  相似文献   

10.
旨在提高解淀粉芽孢杆菌M1液体发酵产芽孢量,并考察其对实际废水的反硝化脱氮效果。首先采用单因子实验研究了碳源、氮源、初始pH值、温度、转速和装液量等因子对M1液体发酵产芽孢量的影响。然后对其中显著性因子:氮源浓度、接种量、装液量、温度4个因素进行正交试验,进一步优化发酵条件。结果显示,优化后的培养基成分为:5 g/L碳源(可溶性淀粉)、10 g/L氮源(酵母粉∶蛋白胨=2∶1)、1 g/L NaCl;最佳培养条件为:初始pH6.5、发酵温度34℃、摇床转速180 r/min、培养瓶装液量30%、接种量7%。在此条件下,芽孢杆菌M1芽孢数可达到6.8×108 CFU/mL,高于优化前的2.08×108 CFU/mL。将芽孢杆菌M1投加于反应器中,与不加菌种相比,反硝化脱氮效果提升15%-34%。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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