摘要
以５００ｍｇ／Ｌ亚硝基胍诱导处理球形红假单胞菌株Ｐ５１１００，从中挑出１００株诱变菌株，经初筛和复筛，获得理想菌株Ｐ５１１９０。Ｐ５１１９０的沉降性能优于出发菌株Ｐ５１１９０在沉降管中测出的沉降效率比Ｐ５１１９０提高１倍多．以４．６‰聚合硫酸铁絮凝沉降突变菌株Ｐ５１１９０菌液，菌体去除率达９９．７％．以聚合硫酸铁絮凝沉降出发菌株菌液的最佳浓度为５．２‰，去除率为９０％．理想菌株Ｐ５１１９０可以节约聚合硫酸铁用量１２％，去除菌体效率提高９．７％．
Rhodopseudomonas sphaeroides strain P5100 was treated by 500 mg/ L N-menthyl-N'-nitro-N'-nitros with 30℃ for 30 minutes for inducing high settling characteristics of the cell. 100 mutant strains were used as the first screening strains after the mutagenic test and from which 4 mutant strains got were used as the second screening material and then the ideal mutant P51190 was found. 30% P51190 free cells were integrated into two or three cells, increasing the size of cell grain and the settling efficiency.The settling efficiency R(%) value for Rhodopseudomonas sphaeroides both for P51100 and P51190 was measured in settling tube (with 1 cm diameter and 50 cm highness)which was made of glass. The cells of P51100 and P51190 were washed twice with pH7.0 phosphorate buffer before the R(%) value tested. The clean cells were resuspended in the buffer and then turned into the settling tube. R(%) is equal to (OD- OD)/ OD .OD means the cell light dnsity value in the buffer with 660um wave length at the beginning time (to) and OD means that at time tn. From 0￣ 30cm highness of settling tube, all the R values are negative. It shows that the OD value of the cells decreased following the test time (tn) from 20minute to 100 minute and there is a significant negative relativity between R values and tn. From 30 to 40cm highress of the settling tube there is no significant relativity between R and tn. All the R values are positive in the settling tube from 40￣ 50cm highness section and there is a good positive relativity between R and tn from 20 minutes and 100minutes. The settling rate R(%) of P5119omutant is as high as two times of P5100 while the tn is 100 minutes and'the highness is from 40￣ 50 cm section.Although the P51190 R is higher than P51100, it will not be a satisfaction in production practice. So it is necessary to design another experiment for improving its settling efficiency with flocculant polyferric sulfate. The total removal rate E(%) for P51190 and P5100 cells by polyferric sulfate is measured in the settling column made of glass (with 4.5cm diameter and 60cm highness) from 20minutes to 60 minutes. E= P(%)is equal to (OD- OD) / OD when the cells are at each highness section and at each time with polyferric sulfate. On the basis of each P value obtained we could get a equivalent curve of cell removal rate between each highness section (h n) and each test time (tn).From this equivalent curve, the total E(%) value at each tn Could be calculated, and then we could get another curve between each E(%) value and each tn, from which the highest E(%) and the most suitable test time (tn) should be found. The suitable settling time is 30minutes (tn) and the highest E% value is 73% in this experiment with polyfernic sulfate as flocculant for P51190 while the concentration of polyferric sulfate is 0.46% and the solution PH is 4. If the concentration of pdyferric sulfate increased to 0.52%, 99.7% P51190 biomass could be removed. 12% polyferric sulfate for removing P51100 biomass could be saved by P51190 and the removal rate is 9.7% higher than P51100.
出处
《南京大学学报（自然科学版）》
CSCD
1994年第3期469-476,共8页
Journal of Nanjing University（Natural Science）
基金
国家自然科学基金
关键词
红假单胞菌
沉降
絮凝
废水处理
Rhodopseudomonas sphaeroides, N- menthyl-N'-nitro -N-nitrosoguanidine, mutation, settling characteristics, polyferric sulfate, focculation
