单级自养脱氮系统中生物膜EPS提取方法

Extraction of extracellular polymeric substances from biofilm of completely autotrophic nitrogen removal over nitrite(CANON) system

以SBBR单级自养脱氮系统中的生物膜为泥源,采用4种不同的物理方法对生物膜胞外聚合物(EPS)进行了提取实验,采用EPS中DNA的相对含量评价提取方法的优劣。结果表明:超声波法、热提法、蒸汽法和阳离子交换树脂法(CER)提取的紧密结合型EPS(TB-EPS)总量比较接近,但是各提取方法所得的TB-EPS中DNA的相对含量相差较大。CER法提取的TB-EPS总量较高,并且DNA含量较低,是有效的EPS提取方法。实验证明紫外光谱扫描判别TB-EPS提取过程中对细胞的破坏程度与化学分析方法判别一致,因此可以采用紫外光谱扫描简单、快速地判别提取TB-EPS过程中对细胞的破坏程度。

Four physical methods were employed to extract extracellular polymeric substances （EPS） from biofilm samples in a completely autotrophic nitrogen removal over nitrite （CANON） system. The relative amount of DNA in the EPS was used to evaluate the pros and cons of the four extraction methods. The results showed that the total amounts of TB-EPS extracted by soni cation, heat treatment, steam and cation exchange resin （CER） methods were close, but the relative amounts of DNA in the EPS had larger differences among the four methods. The CER was the most effective method for extracting EPS given its higher total TIA-EPS extraction and lower DNA amount. The experimental results prove that the degree of damage to cells during the extraction of TB-EPS using UV wavelength scanning method is the same as that using chemical analysis. Therefore, the UV method can be applied to simply and efficiently determine the degree of damage to cells during the extraction of TB-EPS.