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1.
中性蛋白酶发酵工艺优化研究   总被引:15,自引:0,他引:15  
采用正交试验,对枯草芽孢杆菌HD401中性蛋白酶深层发酵工艺进行了优化,结果表明:较优发酵培养基为玉米粉5%、豆饼粉3%、麸皮4%、NaHPO0.4%、KHPO0.03%;在发酵中期流加蚕蛹水解液5%、植酸钙0.2%、吐温-800.1%,对发酵后期有较大的调控作用。采用优化工艺,在2L发酵罐中进行验证试验,酶活达13200u/ml,比原工艺提高了164%。  相似文献   

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为了实现Ap-2号磷菌肥的工业化生产,对Ap-2号溶磷黑曲霉进行了深层发酵工艺的研究。确定了最佳发酵条件:C/N10:1;菊花糖4%,黄豆饼粉2%,麸皮1%,酵母粉0.5%,MgSO4.7H2O0.05%,K2HP04,0.1%,温度30℃,pH6,摇床转数180r/min,发酵96小时,pH降至3.1,残糖降至1%以下,柠檬酸、草酸总量达3%以上,菌丝浓度达2.5g/ml。采用ES-15型自控发  相似文献   

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对聚β-羟基丁酸(PHB)产生菌Z5-GⅡ的发酵培养基及发酵条件进行优化研究;结果表明:该菌株在蔗糖1%,酵母粉0.3%,酵母浸汁0.3%,K2HPO40.2%;pH7.2 ̄7.4的优化发酵培养基中,接种量8%,种28h,发酵培养36h,细胞干重为6.87g/L,PHB产率可达的细胞干重的61.86%。该菌株还可利用葡萄糖生产废液为碳源生产PHB,具有实现工业化生产的潜力。  相似文献   

4.
一株根霉产脂肪酶发酵条件的研究   总被引:13,自引:0,他引:13  
通过对筛选出的一株根梅RhizopusY-92产旨肪肪酶发酵2基组成(C,N,无机盐)及工艺条件的探索,并经正交实验,得到较优培养基配方为:蛋白胨6%,豆饼粉4%,葡萄糖1%,MgSO4·7H2O0.1%,KH2PO40.3%,起始PH8.0,在此条件下,发酵液酶活可达99.15u/ml,是初始酶活的178%。  相似文献   

5.
甜瓜的组织培养与快速繁殖   总被引:11,自引:0,他引:11  
1植物名称甜瓜(Cucumismelo)品种“状元”。2材料类别顶芽、侧芽。3培养条件初代培养基:(1)MS+6-BA0.2mg·L-1(单位下同)+IAA0.2。增殖培养基:(2)MS+6-BAI+IAA0.2。生根培养基:(3)Miller+IAA0.2;(4)Miller(无激素)。以上培养基pH均为5.8~6.0。琼脂浓度在(1)、(2)中为0.7%,在(3)、(4)中为0.6%;糖浓度在(1)、(2)中为3%,在(3)、(4)中为2%。培养温度均为(25±3)℃,光照度2000lx,光…  相似文献   

6.
多孔菌液体发酵的研究   总被引:1,自引:0,他引:1  
多孔菌Polyprouselegans(Bull)Fr。是一种新开发的真菌类中药材资源,经对其几个主要液体发酵培养条件的筛选研究,初步得出多孔菌深层发酵的基础参数:PH5.6~0.1;温度24~28℃;培养基为麦麸2.5%,蔗糖4%,NH4NO30.05%,KH:PO40.05%,MgSO4·7H2O0.025%。另外,摇瓶种子培养条件是:PH5.6~6.1;温度28℃;培养基为PDA+VB1,添加3‰琼脂,时间为96hr。  相似文献   

7.
外源^65Zn进入土壤后的扩散及存在形态   总被引:2,自引:2,他引:0  
利用65Zn示踪和化学连续分级技术研究了外源Zn在褐土中的存在形态。结果表明交换态Zn(EX-Zn)和碳酸盐结合态Zn(CARB-Zn)含量约占土壤总Zn量的67-72%.Zn投加量增加,土壤Zn的强度因数增大.反之,Zn的矿物形态增高.土壤水分4%和100%时,土壤中Zn的扩散系数D分别是7.9×10-8和6.6×10-6cm2·s-1.土壤水分含量在30%和70%时,Zn在施入点的平均停留时间分别是9d和4d.Zn的扩散程度(σ2)也随之从0增大到0.371.  相似文献   

8.
肖亚中  张洁 《生物学杂志》1996,13(5):23-23,42
对栀子蓝色素摇瓶发酵生产的培养基配方进行了优化研究。结果表明,在栀子基质溶液中添加1.5%的可溶性淀粉、0.75%的胰蛋白胨和0.10%的MgSO4,可使栀子蓝色素的摇瓶产量提高15.6%。  相似文献   

9.
采用含有稳定同位素 ̄(15)N-硫铵为主要氮源的专用发酵培养液配方和相应的工艺条件,在国内首次用微生物直接发酵研制成L-缬氨酸- ̄(15)N高丰度精制产品。产品 ̄(15)N丰度97.68%,反比原料 ̄(15)N-硫铵丰度下降0.53%,L-缬氨酸- ̄(15)N产酸率最高达4%以上(未校正)。每克 ̄(15)N-硫铵可得到1克以上的L-缬氨酸- ̄(15)N(分析值)。提取精制收率平均为80-90%(单程),最高达到95%以上(二次提取)。实际每克 ̄(15)N-硫铵可得0.6克左右的L-缬氨酸- ̄(15)N精制产品。  相似文献   

10.
米根霉发酵生产L-乳酸   总被引:11,自引:0,他引:11  
报道了L-乳酸菌株的分离与筛选,探讨了不同碳源、氮源、通气量、温度等发酵条件对产L-乳酸的影响,从78株米根霉中筛选出13株产L-乳酸较高的菌株,其中米根霉(Rhizopus oryzae)Rs928产L-乳酸最高,产酸最稳定。试验结果表明,该菌株最适发酵培养组成(%):淀粉水解糖16,MgSO4 0.08,KH2PO4 0.05,ZnSO4 0.01,CaCO3 7,pH自然。在60t发酵罐中,  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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16.
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   

17.
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   

18.
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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