【摘要】：從長期施用二氯喹啉酸的土壤中分離到1株能以二氯喹啉酸為碳源生長的菌株,命名為PFS-4。經16S rRNA基因序列和生理生化特性分析,將菌株PFS-4鑒定為施氏假單胞菌(Pseudomonas stutzeri)。以麥稈吸附-海藻酸鈉包埋方式對菌株進行復合固定,采用正交實驗對固定條件進行優(yōu)化,研究溫度、pH值、碳源對固定化菌劑降解二氯喹啉酸的影響;考察固定化菌劑對污水中二氯喹啉酸的去除效果,并對比分析游離菌及固定化菌劑去除能力的差異。結果表明,固定化菌劑制備的最佳條件為:海藻酸鈉質量分數(shù)為5%,Ca Cl2為4%,菌膠比1∶2,交聯(lián)時間5 h。在溫度為30℃、pH值為7的條件下,經5 d培養(yǎng),固定化菌劑對500 mg·L~(-1)二氯喹啉酸降解率為92.3%。在處理污水中二氯喹啉酸時,游離菌的降解能力受到極顯著抑制(P0.01),而對固定化菌劑降解率影響相對較小,去除率保持在64%以上。麥稈吸附-海藻酸鈉包埋固定化菌劑對不良環(huán)境具有較好緩沖性,可用于微生物降解菌的開發(fā)利用。
[Abstract]:A strain, named PFS-4., which can grow with dichloroquinolinic acid as carbon source, was isolated from the soil treated with dichloroquinolinic acid for a long time. The 16s rRNA gene sequence and physiological and biochemical characteristics were analyzed, and the strain PFS-4 was identified as (Pseudomonas stutzeri). The strain was immobilized by wheat stalk adsorption-sodium alginate. The optimum conditions were optimized by orthogonal experiment. The effects of temperature pH value and carbon source on the degradation of dichloroquinolinic acid by immobilized bacteria were studied. The effect of immobilized bacteria on the removal of dichloroquinolinic acid from sewage was investigated, and the difference between free bacteria and immobilized bacteria was analyzed. The results showed that the optimum conditions for preparation of immobilized bacteria were as follows: sodium alginate was 5% Ca Cl2, the ratio of bacteria to gum was 1: 2, and the crosslinking time was 5 h. The degradation rate of 500 mg L ~ (-1) dichloroquinolinic acid was 92.3 when the temperature was 30 鈩，

本文編號：2203999