Based On The Living But Not Culturable Bacteria Degradation Of Chlorpyrifos And Its Enzyme Degradation Effect

From the bacterial cultivation environment, such as:soil, activated sludge, sea, lake and sediment by pure cultures ofmicroorganisms using traditional methods, only occupy 0.01-10 percent of all, but there is more than 90% bacteria, in viable but non-culturable (VBNC) state, are not widely been known. With the development of modern biological technology, a variety of research methods about molecular biology provide us with more approaches to know the VBNC state. Although culture-independent approaches can get a lot of information on the composition of the microbial diversity and flora, the research of biology and ecology function is still limited. Recently, nvestigations of the VBNC bacteria have been increasingly recognized. We used most probable number (MPN) method, combined with Rpf (resuscitation promoting factor) to isolate the VBNC bacteria from Xinjiang soil and pharmaceutical waste water.14 strains, which could degrade Chlorpyrifos, were isolated. Efficient chlorpyrifos-degrading bacteria and corresponding enzymes were screened by using routine methods, explored the appropriate optimal conditions of the degradation enzyme. The main researches as follows:1. Some VBNC bacteria were isolated from Xinjiang soil and pharmaceutical wastewater by using most probable number (MPN) method and Rpf. These strains were identified based on morphological features and 16s rRNA sequence analysis. Through comprehensive analysis of phylogenetic evolution of bacteria, which have function—chlorpyrifos degradation in related literature,14 VBNC strains were screened.2. One of the 14 strain—CHZYR63, identified as Pseudomonas fluorescens, hadthe highest degradation efficiency. BBD response surface method optimizes degrading condition. The experiment results showed:after cultivating 7 days, when temperature and pH was 29℃ and 7, respectively, its degradation rate of chlorpyrifos (131mg/L) was as high as 70.15%.3. Intracellular and extracellular enzyme, which extracted from the strain—CHZYR63, whose degradation rate could reach 48.4% and 59.83%, separately. Research on degradation conditions of extracellular enzyme shows that: concentration of chlorpyrifos was 100mg/L, the optimal temperature of enzymatic reaction was 35℃, pH was 7. chlorpyrifos degradation rate was 60.26% within 30 minutes.This study show that strain CHZYR63 and its enzyme have good effect on degradation of chlorpyrifos, culturable VBNC bacteria not only have great value in degrading pesticide, but also provide important methods and ideas on revealing the formation and recovery mechanism of VBNC bacteria in polluted environment and total metabolism and interaction mechanism of the microbial population, etc. Therefore, research on resuscitation of VBNC state bacteria, based on Rpf and environmental function and microbial resources, is of great significance to find new strains and potential environment function. At the same time, it can provide new scientific basis for the recognition and evaluation of microbial pollution in environmental remediation, protection and other fields.