贵州喀斯特土壤放线菌的分离鉴定及多样性研究

发布时间：2018-01-07 14:17

本文关键词：贵州喀斯特土壤放线菌的分离鉴定及多样性研究　出处：《东华理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：贵州是东亚喀斯特片区中心,是世界三大喀斯特集中区之一。微生物是土壤中最活跃的部分,是生态系统中能量流动和物质循环的主要推动者。而放线菌主要存在于土壤中,放线菌能够产生大量的具有生物活性的次级代谢产物,因此对土壤放线菌的研究具有重要的价值。贵州喀斯特区域土壤放线菌资料目前还非常有限,亟需进行深入细致的研究。本研究采用不同的分离方法对贵州万峰林国家地质公园、草海国家自然保护区、双河洞国家地质公园等8个地区的土壤放线菌进行分离和鉴定,对其多样性进行研究,并对分离得到的菌株进行抑菌活性的研究。具体实验结果如下:1.采用四种不同的方式预处理来处理106份土壤样品,其中用微波干热法的效果最佳。最终获得了76株放线菌。2.采用9种培养基对放线菌进行分离培养,用LNMS分离出来的放线菌数量最多为每克土5.2×105株。燕麦琼胶培养基分离出的放线菌种类数最多,为8种。3.在不同地区、不同植被类型的土壤分离中,耕地中分离出的放线菌数量最多可达4.65×105个/克土。4.在不同生境中,草海的边坡、黄果树林下和双河洞的洞穴的土壤中分离出的放线菌所占比重都在65%以上,在小生境中沟边放线菌种类比重最小为49%,而洞穴放线菌种类所占比重最大为76%。5.在高海拔2400 m时放线菌的种类数量减少,但稀有放线菌的数量有所增加,分别有罗氏菌属、类诺卡氏菌属等。6.采用滤纸片法对放线菌进行抑菌活性测定。有10株放线菌对大肠埃希氏菌和金黄色葡萄杆菌的抑菌直径达到了10 mm以上,其中3菌株对金黄色葡萄杆菌的抑菌直径都在14 mm以上。有12株放线菌对真菌的拮抗性较强,然后用生长速率法进行活性复筛。至少对2种真菌有明显的抑制作用。综合抑细菌实验和抑真菌实验的结果可知,C1、E4这两株放线菌对细菌和真菌均有很好的抑制作用,有继续开发的价值。7.通过对菌株的形态学特征、培养特征和16S rDNA序列分析,可将拮抗性优良的菌株1030、1051、1112、1095、1312归属于链霉菌属。
[Abstract]:Guizhou is the center of karst region in East Asia and one of the three largest karst regions in the world. Microbes are the most active part of the soil. Actinomycetes mainly exist in soil, and actinomycetes can produce a large number of secondary metabolites with biological activity. Therefore, the study of soil actinomycetes is of great value. At present, the data of soil actinomycetes in Guizhou karst region is very limited. This study uses different separation methods to study the Wanfenglin National Geopark and the Caohai National Nature Reserve in Guizhou Province. Soil actinomycetes were isolated and identified from 8 areas such as Shuanghe Dong National Geopark and so on. The diversity of actinomycetes was studied. The antimicrobial activity of the isolated strains was studied. The results were as follows: 1. 106 soil samples were treated with four different pretreatment methods. Among them, microwave dry heating method was the best. Finally, 76 strains of actinomycetes were obtained. 9 kinds of media were used to isolate and culture actinomycetes. The maximum number of actinomycetes isolated by LNMS was 5.2 脳 10 ~ 5 strains per gram soil, and 8 species of actinomycetes were obtained from oat Agar medium, which were found in different regions. In the soil separation of different vegetation types, the maximum number of actinomycetes isolated from cultivated land was 4.65 脳 105 / g soil. The proportion of actinomycetes isolated from the soil of the caves of the Huangguoshu forest and Shuanghe Cave was above 65%, and the percentage of actinomycetes at the edge of the gullies was 49% in the microhabitat. The largest proportion of actinomycetes in caves was 76. 5. The number of actinomycetes decreased at 2400m above sea level, but the number of rare actinomycetes increased, respectively. The antimicrobial activity of actinomycetes was determined by filter paper method. The antibacterial diameter of 10 actinomycetes against Escherichia coli and Grape aureus was more than 10 mm. The inhibition diameter of 3 strains to grape aureus was more than 14 mm, and 12 strains of actinomycetes had strong antagonism to fungi. Then the activity was screened by growth rate method. At least two kinds of fungi were obviously inhibited. E4 two actinomycetes have a good inhibitory effect on bacteria and fungi, which has the value of further development. Through morphological characteristics, culture characteristics and 16s rDNA sequence analysis. The strain 1030, 1051, 1112, 1095 and 1312, which have good antagonism, can be assigned to Streptomyces.
【学位授予单位】：东华理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S154.3

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