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1.
成熟蕃茄匀浆后,经硫酸铵盐析,DEAE-SephadexA-50离子交换层析,SepadexG-100凝胶过滤和Melibiose-Agarose亲和层析,获得了α-D-半乳糖苷酶(C.E.3.2.1.11)。酶制剂经PAGE检测为一条带;SDS-G-PAGE测得酶Mr为34000;比活力52.9U/mg·;提纯倍数为52901产率为45%.酶专-催化以α-D-半乳糖为末端a-(1,3)连接的糖苷键,以PNPG(对硝基苯-α-D-半乳糖昔)为废物,酶催化反应的Km=0.11mmol/L,Vmax为67μmol·mg1-·min-1.t稳定范是0~35℃;PH稳定范围是4.0~7.0.最适pH为5.1.半乳糖是酶的竞争性抑制剂;Cu2+、Zn2+、Mn2+、Fe3+、Ag+和EDTA对酶活性无影响.纯酶制剂可作为B型血向O型血转化的工具酶液.  相似文献   

2.
测定了由光合细菌 P9479 株与酵母 Y9407 株经原生质融合构建的跨界融合子 Foaz 及其亲株在净化豆制品废水反应中0 、0 .1 、5 .0 、10 .0 、100 .0 mg/ L Fe3 + 质量浓度和0 、150 、300 、400 、800 mg/ L Mg2 + 质量浓度下的β-类胡萝卜素色素含量及 B O D5 去除效率.结果表明, Fe3 + 对融合子 Foaz 及光合细菌中β- 类胡萝卜素的合成有明显的促进作用,当ρ( Fe3 + ) 为5 .0 mg/ L 时,融合子 Foaz 及光合细菌中β- 类胡萝卜素的质量分数w 达到最高水平,分别为4 .9 mg/g 和2 .4 mg/g .而 Mg2 + 对融合子及其亲株中β- 类胡萝卜素的合成有一定抑制作用  相似文献   

3.
麻黄愈伤组织细胞的悬浮培养   总被引:14,自引:0,他引:14  
用中麻黄幼苗的3种外植体进行了离体培养。不同外植体诱导愈伤组织的结果表明:最佳培养基为MS+2mg/L2,4-D+1mg/L6-BA;最佳外植体为下胚轴;用源于下胚轴的愈伤组织进行悬浮培养,从第3代开始建立起稳定的悬浮系。愈伤组织、悬浮培养细胞及培养液中都含有麻黄碱,悬浮培养液中的麻黄碱含量高于愈伤组织和悬浮培养细胞。表2参12  相似文献   

4.
长期继代培养马铃薯愈伤组织的植株再生   总被引:12,自引:0,他引:12  
对影响马铃薯愈伤组织发生、生长和长期继代培养的愈伤组织再生植株的几种因素进行了研究。马铃薯茎段的愈伤组织发生频率高于叶片的愈伤组织发生频率。Dicamba诱导茎段和叶片的愈伤组织发生频率在90%以上;而2,4-D的诱导效果不佳并诱发外植体生根。再生培养其中加入0.5g/L的酶解酷蛋白是必需的;蔗糖的浓度以2%-4%为宜;附加ZT2.0mg/L、GA0.1mg/L可使长期继代的愈伤组织的植株再生频率  相似文献   

5.
食酸丛毛单胞菌AN3菌株降解苯胺的研究   总被引:3,自引:0,他引:3  
报道了各种环境因子对食酸丛毛单胞菌AN3菌株完整细胞降解苯胺的影响.在良好的通气条件下,该菌株完整细胞降解苯胺,最适湿细胞质量浓度ρFW(cel)=20g/L、最适pH和温度θ分别为7.0和30℃,苯胺ρ=1300mg/L左右,经过6h的作用即可被完全降解;各种有机物如葡萄糖和蛋白胨对苯胺的降解均有延缓的作用:除Hg2+和Ag+外,其他重金属离子对苯胺降解抑制作用较小  相似文献   

6.
不同消毒剂对水中脊髓灰质炎病毒灭活的比较   总被引:4,自引:1,他引:3  
将脊髓灰质炎病毒( Polio V) 及不同消毒剂投加到模拟水样中,按不同接触时间1 ,3 ,10 ,30 min 取样,空斑定量. 当模拟水有机质含量 C O D 为20 mg/ L,病毒浓度n( P F U) ≈1 ×105 m L- 1 时,分别投加氯制剂有效氯ρ( Cl)16 mg/ L,接触30 min ;ρ( Cl O2) = 8 .0 mg/ L,30 min ; Cl+ Cl O2 联合消毒剂(5 .0 + 5 .0) mg/ L,30 min ;ρ( O3) = 1 .22 mg/ L,10 min 时;可使病毒彻底灭活. 它们使 Polio V 达到99 .99 % 灭活的浓度时间乘积( ρ×t) 值分别是662 .5 ,129 .5 ,200 .0 和3 .2 mg L- 1 min . 消毒效果( 顺序) 为 O3 > Cl O2 > Cl+ Cl O2 > Cl. 联合消毒灭活 Polio V 的效果为 Cl 的3 .3 倍,表明将 Cl 与 Cl O2 联合应用具有协同效应,优于传统的单一加氯消毒方式  相似文献   

7.
硅营养缓解水稻幼苗Cd、Cr毒害的生理研究   总被引:58,自引:0,他引:58  
两系法杂交稻“培杂山青”和常规稻“双桂36”幼苗经较高浓度的Cd2+(c=9.6~38.4μmol/L)或Cr3+(c=7.5~25.0μmol/L)处理可使其叶片光合速率、叶绿素(a+b)含量、叶绿素a/b比值、叶片可溶性糖、淀粉及可溶性蛋白质含量降低,而叶片的POD活性提高;低浓度Cd2+(c=4.8μmol/L)和Cr3+(c=2.5μmol/L)处理幼苗对上述生理指标有提高作用,但POD活性稍降低.加Si(Na2SiO3)[c(SiO2)=1.331mmol/L]的Cd、Cr处理比不加Si的Cd、Cr处理的幼苗叶片上述生理指标明显提高,且明显降低其POD活性.说明Si在不同程度上起到缓解Cd、Cr对水稻幼苗的毒害作用.而c(Cr3+)=25.0μmol/L是“双桂36”幼苗的致死浓度  相似文献   

8.
运用电生理学方法,观察Hg(2+)、Zn(2+)联合对克氏螯虾第一触角内侧枝神经动作电位放电的影响.当Hg(2+)、Zn(2+)浓度分别达到0.000025mg/L和0.05mg/L时,这两种离子联合对触角神经的毒性作用潜伏期(TL)为46.75±22.69min(N=8),触角神经动作电位放电持续时间(DD)为115.28±40.95min,表示其放电频率(Fn/Fl)与作用时间关系的直线回归方程的b值为-0.0818,与渔业水体最高允许Zn(2+)含量0.1mg/L比较,两者间无显著差异(P>0.1).说明Hg2+对Zn(2+)的毒性具有增强效应.因此,在对有Hg(2+)和Zn(2+)污染的水体进行评估时,似应考虑到Hg(2+)对Zn(2+)毒性的增强效应.  相似文献   

9.
啤酒酵母吸附Cu^2+的模拟实验   总被引:17,自引:0,他引:17  
研究了啤酒酵母吸附重金属Cu2+离子的可行性及反应条件对去除作用的影响.结果表明:用啤酒酵母处理Cu2+,在起始浓度ρ0为20~400mg/L的范围内,吸附量w为2.98~12.03mg/g,说明用啤酒酵母去除重金属Cu2+是可行的.吸附反应在10~20min基本达到吸附平衡.最适反应温度(θ)和pH分别为15~20℃和4.0~6.0,酵母细胞有一最适投加用量.Freundlich吸附等温方程的分析表明,η与重金属离子种类有关,与酵母细胞种类关系较小;k值与酵母种类和重金属离子种类有关.  相似文献   

10.
试验了Ni、Zn、Mn、Sn、Cr和Cu等6种重金属及油处理剂对水稻根系的影响,结果表明.水中含Ni0.007mg/1、Cu0.005mg/1时,能阻碍根系的伸长;含Zn0.5mg/1以上时。不利于根系的伸长;水中含Mn20mg/1,Sn、Cr ̄(6-)各5mg/1时,对根系有明显危害;水中含Cr ̄(2+)+Cr ̄(6+)时,当1种离子浓度保持不变,根系的抑制程度随着另1种离子浓度的增加而增大。水中含油处理剂1000mg/1时,能抑制水稻发根。  相似文献   

11.
鉴于鱼类和哺乳动物的谷氨酰胺代谢途径有所不同,为了优化CHSE细胞的培养基和大量培养的过程控制。考察了谷氨酰胺对CHSE细胞生长和代谢的影响.在CHSE细胞批培养中,无谷氨酰胺的M199培养基可以支持CHSE细胞的生长,当初始谷氨酰胺浓度c=0.54mmolL^-1时,细胞可达到最高密度nmax/10^5mL^-1=16.19;而更高浓度的谷氨酰胺(c:1.76-5.62mmolL^-1)对细胞生长有抑制作用.在c=0~5.62mmolL^-1初始谷氨酰胺浓度的批培养中,葡萄糖的利用和乳酸的生成基本一致,随谷氨酰胺浓度的升高,Qglc和Qlac增加,Yn/glc降低.另外,随着初始谷氨酰胺浓度的增加(c=0~3.33mmolL^-1),谷氨酰胺的消耗增加,Yn/gln和Yammo/gln分别下降58%和50%;当初始谷氨酰胺浓度继续增加时,谷氨酰胺的消耗、Yn/gla和Yammo/gln基本不变.此外,当初始谷氨酰胺浓度为0时,丙氨酸成为消耗性的氨基酸;Yala/gln先随初始谷氨酰胺浓度的增加(c=0.54~1.76mmolL^-1)而增加,而后又随初始谷氨酰胺浓度的增加(c=1.76~3.33mmolL^-1)而降低.最后维持不变.图4表3参16  相似文献   

12.
欧洲红豆杉细胞培养的研究   总被引:3,自引:0,他引:3  
从欧洲红豆杉(Taxusbaccata)的嫩茎及什叶诱导出愈伤组织,并对之进行了愈伤组织培养及细胞悬浮培养研究;利用HPLC方法测定了培养物合成紫杉醇的能力.探索了提高培养细胞生长率及紫杉醇含量的一些措施.结果表明,欧洲红豆杉愈伤组织及悬浮培养细胞的生长速率已分别达到0.27g·L-1·d-1和0.35g·L-1·d-1,紫杉醇含量分别为0.0031%和0.017%。  相似文献   

13.
植物细胞代谢产物的诱导释放   总被引:9,自引:0,他引:9  
植物细胞培养是植物有用代谢物质的潜在来源.目前植物细胞培养难以工业放大的一个关键问题是生产成本过高.虽然可通过固定化方法实现植物细胞的连续使用,减少由于接种量过高而产生的附加成本,缩短培养周期,但由于许多代谢产物储存于液泡里,释放量很少或根本不释放,限制了固定化技术在工业上的应用,同时也增加了后期产物分离的操作,因此很多研究者在致力于研究如何诱导细胞次级代谢产物的释放.本文将从以下4个方面的研究进展做一评述.1 培养条件的调控1.1 pH值改变培养基的酸度对代谢物的分泌很重要.研究表明,一些次级代谢物是与H 通过…  相似文献   

14.
通过7L罐考察了不同葡萄糖流加速率以及添加L-半胱氨酸对产朊假丝酵母(Candida utilis)WSH02-08高密度发酵生产谷胱甘肽(GSH)的影响.结果表明,在恒定速度(5.5g L-1h-1)流加葡萄糖30h的基础上,发酵45h后细胞干重最高达到73g L-1,此时向发酵罐中一次性添加L-半胱氨酸40mmol L-1,最终GSH产量和胞内GSH含量分别达到了1458mg L-1和2.26%.图4表1参11  相似文献   

15.
红豆杉培养细胞紫杉醇的分离及鉴定   总被引:2,自引:0,他引:2  
红豆杉培养细胞紫杉醇的分离及鉴定甘烦远,郑光植,彭丽萍,沈月毛(中国科学院昆明植物研究所昆明650204)关键词红豆杉;紫杉醇;细胞培养;分离鉴定ISOLATIONANDIDENTIFICATIONOFTAXOLFROMCULTUREDCELLSOF...  相似文献   

16.
甘薯细胞悬浮培养的建立及其生长研究   总被引:8,自引:0,他引:8  
由甘薯叶片诱导出愈伤组织,并由此建立起悬浮培养细胞系.分析其生长表明:南薯88和81294两种细胞系生长曲线均呈“S”型,其中南薯88生长较快,是81294的3倍以上,10d培养物的鲜重是初始鲜重的10倍.培养条件研究结果表明:南薯88细胞悬浮培养的最佳2,4D质量浓度为1.0mgL-1,最佳蔗糖质量浓度为30gL-1,椰乳和酵母汁能明显促进其生长;对于81294,2,4D最佳质量浓度为2.5mgL-1、蔗糖最佳质量浓度15gL-1,酵母汁可促进其生长,但椰乳却无效;谷氨酰胺、色氨酸和脯氨酸不能促进甘薯悬浮细胞的生长,水解酪蛋白对其生长的促进作用亦不大;葡萄糖则抑制其生长  相似文献   

17.
Lake Van is the largest lake in Turkey. The lake limits lifespan due to its high pH and brackish water. For this reason, only a single species of fish (Van Fish) is living in the lake that has been adapted to these conditions. In the present study, we investigated the total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA) level and DNA damage effect of bisphenol A (BPA) (10?7, 10?6 and 10?5?M) on primary gill cell culture of Van Fish for 24 and 48?h of incubation periods. TAS levels were not changed when compared to those of the control group, but TOS levels were decreased in both 24 and 48?h. The MDA level increased only at the highest concentration (10?5) at the end of 12 and 24?h (p?.05). DNA damage increased only at the 10?5?M concentration after 48?h. At the end of the experiment, BPA exposure caused lipid peroxidation and genotoxic effect. These results indicate that high levels of BPA exposure induced oxidative stress and DNA damage by time- and concentration-dependent fashion in the gill cell culture of Van Fish. Gill cell culture is a useful model for the rapid identification of the harmful effects of chemicals in the aquatic environment.  相似文献   

18.
Perennial monoculture forming grasses are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential. Transfer of key genes for mercury phytoremediation into the salt marsh cordgrass (Spartina alterniflora) is reported here. S. alterniflora plays an important role in the salt marsh by cycling of␣elements, both nutrients and pollutants, protects the coastline from erosion, is a keystone species in the␣salt marsh supporting a large food web, which in turn supports a significant segment of economy, including tourism, has an impact on cloud formation and consequently on global weather, and is thus an ecologically important species relevant for our life-support systems. Embryogenic callus of S. alterniflora was co-inoculated with a pair of Agrobacterium strains LBA4404 carrying the organomercurial lyase (merB) and mercuric reductase (merA) genes, respectively, in order to co-introduce both the merA and the merB genes. Seven stable geneticin resistant lines were recovered. The presence of merA and merB genes was verified by PCR and Southern blotting. All but one transgenic lines contained both the merA and the merB sequences proving that co-introduction into Spartina of two genes from separate Agrobacterium strains is feasible and frequent, although the overall frequency of transformation is low. Northern blotting showed differences in relative expression of the two transgenes among individual transformants. The steady-state RNA levels appeared to correlate with the phenotype. Line #7 showed the highest resistance to HgCl2 (up to 500 μM), whereas line #3 was the most resistant to phenylmercuric acetate (PMA). Wild-type (WT) callus is sensitive to PMA at 50 μM and to HgCl2 at 225 μM.  相似文献   

19.
Bacterial systems have not had success predicting metal carcinogenicity. Hypotheses explaining this failure are examined. Using a broad genetic endpoint, λ prophage induction, under sub‐toxic growing conditions, genotoxicity is seen for compounds of chromium, manganese, lead, molybdenum and tungsten. Copper, manganese, arsenic and molybdenum compounds enhanced UV mutagenesis in E. coli WP2.

The toxicity of metal compounds to cultured mammalian cells correlates well with rat oral LD50 values. Whereas insolubility can present problems in bacterial studies, concentrations of metal compounds toxic to mammalian cells can be determined even in the presence of precipitate, and sometimes [Pb(NO3)2, BaCl2 and BeCl2] occurs only in its presence. PbS and MnS, which are insoluble, are much more toxic than the more soluble compounds Pb(NO3)2 and MnCl2. These results demonstrate the importance of cellular phagocytosis of insoluble metal compounds as a factor in studying the toxicity and genotoxicity of metal compounds.  相似文献   

20.
Imprinting plays a key role in the development of species recognition, with young imprinting upon the morphological characters of their parents. However, the potential role that cultural transmission might play in species recognition remains largely uninvestigated. Great tits (Parus major) and blue tits (Cyanistes caeruleus) do not normally perceive each other as sexual competitors or potential partners. However, after reciprocal interspecific cross-fostering, both species may perceive individuals of the foster species as potential rivals or mates. Although the experience of being raised by heterospecifics clearly has affected the species recognition of cross-fostered birds, some of them breed naturally with conspecifics. The offspring of such cross-fostered birds (OCF) are hence raised by parents that look like ordinary conspecifics but display deviant species recognition as compared to controls in terms of aggressive response towards rivals. Comparing the aggressive behavior of OCF, cross-fostered birds and controls towards territorial intruders may thus help tease apart the influence of morphological vs behavioral cues of parents in the development of offspring species recognition. To this end, we compared birds from all three treatments with respect to their aggressive response to territorial intruders of both species during the breeding season. OCF and controls did not differ in their pattern of response towards heterospecific and conspecific stimuli. Compared to cross-fostered birds, OCF and controls showed less aggression towards heterospecific intruders, while the response towards conspecific intruders did not differ between treatments. These results demonstrate that both tit species imprint on the morphological characters of their parents, but that parental behavior is not important for the development of species recognition in terms of aggressive response towards territorial intruders.  相似文献   

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