原文由 去年冬天(7336167) 发表:
通过从土壤中分离纯化细菌,初步掌握微生物的分离纯化方法和无菌操作技术。
二 实验原理
- 常用的分离纯化方法
microorganisms exist in nature as mixed populations. However, to studymicroorganisms in the laboratory we must have them in the form of apure culture, that is, one in which all organisms are descendants ofthe same organism.
单细胞挑取法
简易单细胞挑取法
micromanipulator
平板分离法
streak plate method
The most common way of separatingbacterial cells on the agar surface to obtain isolated colonies is thestreak plate method. It provides a simple and rapid method of dilutingthe sample by mechanical means. As the loop is streaked across the agarsurface, more and more bacteria are rubbed off until individualseparated organisms are deposited on the agar. After incubation, thearea at the beginning of the streak pattern will show confluent growth,while the area near the end of the pattern should show discretecolonies.
pour plate method
Another method of separating bacteria is thepour plate method. With the pour plate method, the bacteria are mixedwith melted agar until evenly distributed and separated throughout theliquid. The melted agar is then poured into an empty plate and allowedto solidify. After incubation, discrete bacterial colonies can then befound growing both on the agar and in the agar.
spread plate method
The spin plate method involves diluting thebacterial sample in tubes of sterile water, saline, or broth. Smallsamples of the diluted bacteria are then pipetted onto the surface ofagar plates. A sterile, bent-glass rod is then used to spread thebacteria evenly over the entire agar surface.