死谷芽孢杆菌分离鉴定及其污泥减量特性

SCREENING AND IDENTIFICATION OF A BACILLUS VALLISMORTIS STAIN AND ANALYSIS OF ITS PROPERTIES OF SLUDGE REDUCTION

为研究缺氧-好氧-沉淀-厌氧(A+OSA)污泥减量工艺微生物特性,从A+OSA污泥减量系统中分离筛选得到一株特异菌株JL4。通过形态特征、16S r DNA序列分析和系统发育分析,菌株JL4与Bacillus vallismortis位于同一簇群,同源性100%,将其鉴定为死谷芽孢杆菌。污泥分解实验表明其对灭菌后的污泥底物具有降解作用,经过JL4菌处理72 h后,污泥浓度下降了25.7%,污泥上清液COD浓度增加了4.6%。直接将JL4菌接种至灭菌后污水48 h后,JL4菌COD降解率能够达到43.7%,且JL4菌能直接进入对数期的生长,其表观增长率(Yobs)为0.026 h-1,Yobs远低于降解碳水化合物的好氧异养微生物的表观产率。JL4菌可能是A+OSA污泥减量系统的功能微生物之一。

In order to investigate the microbiological properties of the anoxic-oxic-settling-anaerobic( A + OSA) excess sludge reduction system,a special bacterial strain named JL4 was isolated from the A + OSA system. Based on analysis of the morphological feature,16 S r DNA sequence and phylogeny,the strain JL4 was classified as Bacillus vallismortis,and the sequence homology was more than 100%. The sludge concentration reduced by 25. 7% and the COD concentration increased by 4. 6% when the strain JL4 was inoculated to the sterilized sludge suspension after 72 h. Research on nature of JL4 growth showed that it could directly enter into the logarithmic phase of growth. The COD removal rate could reach 43. 7% when the strain JL4 was inoculated to the sterilized wastewater after 48 h. The observed growth yield( Yobs) of JL4 strain was 0. 026 h-1which was lower than other aerobic heterotrophic microbes. The ability of sludge reduction and low Yobsof JL4 strain might be one of function strains of the A + OSA sludge reduction system.