海水蛭弧菌分离纯化方法初步研究

Separation and purification of Bdellovibrio from seawater

蛭弧菌(Bdellovibrio)广泛存在于自然水体,它具有噬菌的特性,对水体中细菌数量控制具调节作用,有可能是进行生物防治的一种重要生物。本文比较不同分离方法、上层培养基营养盐浓度和富集培养与直接培养等对海水蛭弧菌分离、计数的影响,从而建立了海水蛭弧菌分离和纯化的方法。应用无营养盐的海水双层琼脂平板法,采用6种宿主菌分别对海南4份海水样品进行计数检测,发现不同宿主菌所得到的蛭弧菌数量不同,同时对分离纯化到的3株海水蛭弧菌进行液体培养增殖,进一步检验了海水双层琼脂法的可靠性。

Bdellovibrios are obligate predatory bacteria, widely distribute in nature and regulate the counts of bacterium in water. It may be an important organism in the ecological control of fish diseases. In this paper the effects of different ways of separation culture, dilution of nutrient- broth agar at top layer, direct and enrichment culture on separation and counts of marine Bdellovibrio were compared to establish the best method of separation and purification. A total of 6 species of host bacteria was used to quantitatively determine Bdellovibrios in 4 samples of seawater with nature seawater double-layer agar technique. The results revealed that the number of plaques of Bdellovibrio has varied with different host bacteria. On the basis of the results, 3 strains of Bdellovibrio were multiplied in liquid to further examine the reliability of the seawater double-laver agar technique.