一株可溶性有机磷去除菌的分离及其生物学特性

Isolation of a Dissolved Organic Phosphorus-removing Strain and Its Biological Characteristics

摘要:

以甘油磷酸钠(Sodium Glycerophosphate, 以下简称NaGly)作为外源可溶性有机磷, 从富营养化的养殖池污泥中分离到5株可溶性有机磷去除菌株, 通过除磷率比较, 筛选出一株最为高效的菌株D2, 其对初始浓度为5 mg/L甘油磷酸盐磷(Phosphorus Glycerophosphate, 以下简称GP-P)的去除率可达99.0%。此外, 对其进行了16S rRNA基因序列测定, 并进一步研究了其生长特性与除磷特性。试验结果表明, 菌株D2为肠球菌(Enterococcus sp.), 与屎肠球菌(Enterococcus faecium)菌株KT4S13 (登录号: AB481104)和CICC6078 (登录号: DQ672262)的16S rRNA 基因序列相似性近100%; 其生长周期为: 0-4 h为生长迟缓期, 4-8 h为对数生长期, 8-28 h为稳定期, 28 h以后为衰亡期; 且在15°C-40°C、pH 4.0-9.0以及5-40 mg/L GP-P条件下均能够生长, 其中菌株D2最适生长的温度范围和pH范围分别为30°C-35°C、6.0-7.0, 而且20-30 mg/L GP-P能显著促进菌株D2生长。此外, 菌株D2在进入衰亡期之前随着作用时间的延长, 对20 mg/L GP-P的除磷率逐渐升高, 在进入衰亡期后的28-32 h内对20 mg/L GP-P的除磷效果趋于稳定, 其在15°C-40°C、pH 4.0-9.0以及5-40 mg/L GP-P条件下均具有除磷作用, 其最适除磷温度范围、pH范围和GP-P浓度范围分别为25°C-35°C、6.0-7.0和5-10 mg/L。

Abstract:

The study was conducted to screen and isolate dissolved organic phosphorus removal bacteria in soils taken from the eutrophic pond by adopting sodium glycerophosphate (NaGly) as exogenous dissolved organic phosphate. By comparing dissolved organic phosphorus removing abilities between five isolated bacteria, the most effective dissolved organic phosphorus removal bacterium named D2 was chose. In liquid media contained 5 mg/L phosphorus glycerophosphate (GP-P), the phosphorus-removal ratio of the strain D2 could reach 99.0%. Based on the 16S rRNA analysis, the strain D2 exhibited high similarity (Almost 100%) with Enterococcus faecium KT4S13 (Accession number: AB481104) and CICC6078 (Accession number: DQ672262), so it was identified as Enterococcus sp.. The growth characteristics and phosphorus removing abilities of the strain D2 were measured. The growth curve of the strain D2 was as follows: lag phase was 0-4 h, log phase was 4-8 h, stationary phase was 8-28 h, decline phase was after 28 h. Additionally, the phosphate-removal ratio of the strain D2 increased gradually before decline phase, and it could maintain the phosphate removal effect stability for 4 hours after the decline phase. Results also exhibited that the strain D2 could grow normally with temperature ranging from 15°C to 40°C, pH from 4.0 to 9.0 and initial GP-P concentration from 5 mg/L to 40 mg/L, meanwhile the optimal temperature and pH for growth varied from 30°C-35°C and 6.0-7.0. Moreover, the GP-P could significantly promote the growth of the strain D2 when its concentration was from 20 mg/L to 30 mg/L. In addition, the 20 mg/L GP-P removing capability was found gradually increased with extension of action time before the coming of decline phase and keep stability from 28 h to 32 h after entry of decline phase. The D2 had the phosphorus removal ability at the condition of temperature of 15°C-40°C, pH of 4.0-9.0 and concentration of 5-40 mg/L. The optimal range of temperature, pH and initial GP-P concentration for the dissolved organic phosphorus removing capability ranged from 25°C-35°C, 6.0-7.0 and 5-10 mg/L , respectively.