污泥厌氧消化和后续处理中沙门氏菌杀灭及VBNC发生  

Inactivation and VBNC occurrence of Salmonella spp.in sewage sludge by anaerobic digestion and subsequent treatment

作　　者：符波[1] 王燕[1] 姜谦[1] 陈燕[1] 刘和[1] 

机构地区：[1]江南大学环境与土木工程学院,环境生物技术研究室,江苏无锡214122

出　　处：《中国环境科学》2013年第1期103-110,共8页China Environmental Science

基　　金：国家自然科学基金资助项目(50978124);中央高校基本科研业务费专项资金(JUSRP31105)

摘　　要：应用最大或然数（MPN）培养法和反转录定量PCR（RT-qPCR）技术研究了4种污泥厌氧消化方式以及后续处理过程中沙门氏菌杀灭及有活性但不可培养（VBNC）状态的发生情况.中温厌氧消化（MAD）和高温预处理后中温消化（65℃＋MAD）的沙门氏菌分别减少了2.8和5.6个数量级;高温厌氧消化（TAD）和高温-中温两相厌氧消化（TPAD）的沙门氏菌含量均低于检测限.沙门氏菌的杀灭速率常数排序为65℃＋MAD〉TAD〉TPAD〉MAD.结果显示高温对病原菌的灭活效果显著增加,高温短时预处理使得杀灭速率明显加快.TAD和TPAD的污泥VBNC沙门氏菌数量高于MAD和65℃＋MAD 2个数量级,表明长时间的高温厌氧消化易导致沙门氏菌进入VBNC状态.消化污泥经过离心脱水后会出现沙门氏菌数量增加的现象,MAD、65℃＋MAD、TAD和TPAD的消化污泥中沙门氏菌分别增加了1.1、2.4、3.7和2.5个数量级.但其中VBNC状态的沙门氏菌数量明显降低了1~3个数量级,表明消化后污泥中部分VBNC沙门氏菌在离心脱水过程中复活并生长,使得MPN检测得到的可培养沙门氏菌数量增加,初步解释了消化污泥经离心脱水后的病原菌再生长现象.消化污泥中沙门氏菌数量在室温放置过程中会进一步下降.The inactivation and viable but non culturable（VBNC） occurrence of Salmonella sp.in sewage sludge by anaerobic digestion and subsequent treatment was investigated by Most probable number（MPN） and Reverse transcription quantitative PCR（RT-qPCR） method.Four anaerobic digestion processes had different effects on the inactivation of Salmonella spp.The reductions of Salmonella spp.in sewage sludge after mesophilic anaerobic digestion（MAD） and high temperature（65℃） pretreatment anaerobic digestion（65℃＋MAD） were 2.8 and 5.6 orders of magnitude.Thermophilic anaerobic digestion（TAD） and temperature-phased anaerobic digestion（TPAD） exhibited excellent efficiencies on the inactivation of Salmonella spp.with the final content below the detection limit.The inactivation rate coefficients decreased in the following order： 65℃＋MAD（39.64 d-1）,TAD（3.75 d-1）,TPAD（2.96 d-1） and MAD（0.21 d-1）,indicating the high temperature accelerated the inactivation of Salmonella spp..The logarithmic densities of VBNC Salmonella spp.in sewage sludge after TAD and TPAD are 2 orders of magnitude higher than that after MAD,65℃＋MAD,indicating the high temperature led to more pathogens entering into the VBNC state.Salmonella spp.densities in digested sludge increased after centrifuge dewatering with the logarithmic increase of 1.1,2.4,3.7 and 2.5 for MAD,65℃＋MAD,TAD and TPAD,respectively,but the densities of VBNC Salmonella spp.significantly decreased after dewatering with the values of 1~3 orders of magnitude,which indicated that several VBNC Salmonella spp.in digested sludge reactivated after centrifuge dewatering,resulting the increase in the number of culturable Salmonella spp.by MPN.The results revealed that the regrowth of Salmonella in digested sludge was attributed to the reactivation of Salmonella in VBNC state.The Salmonella content gradually decreased in the subsequent storage at room temperature.

关 键 词：污泥 厌氧消化 沙门氏菌 VBNC RT-QPCR 

分 类 号：X705[环境科学与工程—环境工程]