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1.
细黄链霉菌产木聚糖酶的研究   总被引:1,自引:0,他引:1  
通过多因子摇瓶发酵优化实验,以细黄链霉菌为始菌,研究产木聚糖酶的情况.以甘蔗渣为惟一碳源,测定不同甘蔗渣含量的培养基中细黄链霉菌所产木聚糖酶的活力,同时测定氮源、接种量对该菌产木聚糖酶的影响,结果表明,其最适碳源含量为10%,最适氮源为酵母膏和硫酸铵的混合氮源,其最适接种量为5%;在装料50mL的三角摇瓶中于30℃、120rpm振荡培养5d后,发酵液中木聚糖酶活力达7.74IU/mL.  相似文献   
2.
经过溶剂萃取壮观链霉菌发酵菌体、浓缩萃取液获得色素浸膏,再经过柱层层析、薄层层析从1L的发酵菌体中获得1.06g的红色素纯物质。研究了壮观链霉菌红色素的热稳定性、氧化还原稳定性和pH稳定性;并针对柠檬酸、苯甲酸钠、抗坏血酸和蔗糖等常用的食品添加剂对红色素稳定性的影响进行了探讨,及初步研究了其抗菌生理活性,结果表明:除pH(>7.0)对壮观链霉菌红色素有明显的影响外,高温、食品添加剂等对其稳定性无不良的影响。红色素表现出较好的抗菌(革兰氏阳性菌和啤酒酵母)生理活性。  相似文献   
3.
马铃薯疮痂病是由疮痂链霉菌引起的一种危害马铃薯块茎较为严重的土传性病害,在贵州省马铃薯主要产区均有不同程度的发生,给马铃薯的生产带来一定的损失。实验通过研究不同药剂配方对"费乌瑞它"马铃薯疮痂病的影响,筛选出对马铃薯疮痂病防效较好的药剂配方。结果表明,77%氢氧化铜可湿性粉剂+4%春雷霉素可湿性粉剂+3%中生菌素可湿性粉剂、72%农用硫酸链霉素可湿性粉剂+50%王铜可湿性粉剂+20%叶枯唑可湿性粉剂、3%中生菌素可湿性粉剂+72%农用硫酸链霉素可湿性粉剂+40%琥·铝·甲霜灵可湿性粉剂和40%琥·铝·甲霜灵可湿性粉剂+4%春雷霉素可湿性粉剂+50%王铜可湿性粉剂,上述搭配的药剂相对于50%多菌灵可湿性粉剂以及清水对照喷施的效果来比,能够极显著降低马铃薯疮痂病的发病率和提高马铃薯的产量,提高其商品率,且对马铃薯植株性状(株高、茎粗、叶宽和叶长)没有显著的影响。  相似文献   
4.
Two-component genes are kinds of genetic elements involved in regulation of antibiotic production in Streptomyces coelicolor. DNA microarray analysis revealed that ecrA1/A2, which mapped at distant sites from red locus and encode respectively the kinase and regulator, expressed coordinately with genes of Red specific biosynthetic pathway, ecrA1 and ecrA2 gene-disruptive mutants were constructed using homogenotisation by reciprocal double crossover. Fermentation data showed that the undecylprodigiosin (Red) level of production was lower than that of wild-type strain. However, the change of the actinorhodin (Act) production level was not significant compared with wild type. Thus, these experiment results confirmed that the two-component system ecrA 1/A2 was positive regulatory element for red gene cluster.  相似文献   
5.
INTRODUCTION S.coelicolor as a model system has been ex-tensively studied with the aid of genetic and mo-lecular techniques. Its ability to produce four anti-biotics (Hopwood et al., 1995), namely actinorhodin (Act), undecylprodigiosin (Red), Calcium-Depend- ent Antibiotic (CDA) and methylenomycin (Mmy), enables studies of pathyway-specific and pleiotropic regulation of antibiotic production. In which, Red is a red-pigmented antibiotic and Act is coelicolor- pigmented antibiotic tha…  相似文献   
6.
Two-component genes are kinds of genetic elements involved in regulation of antibiotic production inStreptomyces coelicolor. DNA microarray analysis revealed thatecrA1/A2, which mapped at distant sites fromred lucus and encode respectively the kinase and regulator, expressed coordinately with genes of Red specific biosynthetic pathway.ecrA1 andecrA2 gene-disruptive mutants were constructed using homogenotisation by reciprocal double crossover. Fermentation data showed that the undecylprodigiosin (Red) level of production was lower than that of wild-type strain. However, the change of the actinorhodin (Act) production level was not significant compared with wild type. Thus, these experiment results confirmed that the two-component systemecrA1/A2 was positive regulatory element forred gene cluster. Project (No.20172046) supported by the National Natural Foundation of China  相似文献   
7.
采用连续稀释分离法和平板划线分离法的方法,利用以羧甲基纤维素钠为碳源的筛选培养基,从堆肥土壤中共分离获得具有纤维素酶降解能力的菌株15株,其中,菌株ZN-206对纤维素降解能力最强.根据ZN-206菌株的形态特征、培养性状,生理生化指标、细胞壁组成成分及16SrDNA序列进行系统的研究,将菌株鉴定为禾粟链霉菌(Streptomyces graminearus).  相似文献   
8.
从鄱阳湖草洲土壤中分离出一株高产黑色素的细菌(g2B),g2B具有产黑色素速度较快,并且不需要Tyr诱导等优点.在同等条件下其产黑色素能力最强,经提取纯化后产量可达19mg/mL.纯化后的黑色素的红外光谱与SIGMA公司标准黑色素红外光谱图谱基本一致.生理生化分析结果及16s rDNA扩增和序列分析鉴定其种属类型,初步鉴定g2B属于Streptomyces sp..  相似文献   
9.
INTRODUCTION which the hydroxyl group is acetylated, and spi- ramycin III in which the same position is propio- Spiramycin belongs to the macrolide antibi- nylated (Omura et al., 1979). The addition of short-otics group. The molecular structure of spiramycin chain fatty acids stimulates the production of spi-consists of a 16-membered branched lactonic ring …  相似文献   
10.
The relationship between protease and Desferal production was assayed. Experiments were performed using a cultivation of Streptomyces pilosus ATCC 19797 in soybean broth medium containing 2% soybean flour and 2% mannitol. The metabolism of the trihydroxamic acid sidrophore desferrioxamine B and protease production by a S. pilosus in nine continues days after culture were investigated as well as the effect of protease inhibitors was examined. It is found that the Desferal formation decreased with increased protease production. Also the effect of protease inhibitors and minerals in determined day of protease production in the culture medium by S. pilosus has been investigated.  相似文献   
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