含无机盐沉淀菌悬液中微生物生长量的快速测定  

Rapid Measurement of Growth of Bacteria Grown in the Precipitate-containing Liquid Medium

作　　者：赵艮贵[1,2] 薛晓春[2] 杨素萍[1] 

机构地区：[1]华侨大学生物工程与技术系,厦门361021 [2]化学生物学与分子工程教育部重点实验室,太原030006

出　　处：《中国生物工程杂志》2011年第2期91-94,共4页China Biotechnology

基　　金：国家自然科学基金(30970068;31070054);福建省自然科学基金(2010J01209)资助项目

摘　　要：目的：消除菌悬液中无机盐沉淀对比浊法测定生长量的干扰。方法：以嗜有机甲基杆菌ME25为材料，采用比浊法，研究了EDTA对菌悬液中无机沉淀物的清除效应以及对菌体生物量测定的影响。结果：在室温、pH4～11，1．25×10^-2mol／L EDTA与菌悬液样品作用1min，即可去除样品中无机盐沉淀，样品稳定，在lh内不影响样品中菌体吸光度的测定；实际样品和理论样品测定，相对误差小于3．0％，回收率为98％～100％，RSD均小于0．5％。结论：采用螯合剂EDTA可快速去除菌悬液中的无机盐沉淀，有效地消除沉淀物的干扰，明显提高了比浊法测定生长量的准确度，简便易行，具有较高的实用价值。Objective： To eliminate the interference of precipitate caused by inorganic salt in liquid medium on bacterial growth determination by turbidimetry. Methods： Using Methylobacterium organophilium ME25 as a model system, the effects of chelator EDTA on optical density determination and precipitate removal with spectrophotometer are investigated. Results ： Chelator EDTA of 1.25×10^-2mol/L could eliminate completely the precipitate in medium within a minute in the pH from 4.0 to 11.0 at room temperature, and the stability of sample is sustained more than an hour and didn＇ t affect the bacterial density determination at 600 nm （ 0D660）. The data of optical density measured with real samples and standard samples showed the relative error of 3.0% , recovery of 98.0% - 100% , relative standard deviation （RSD） of 0.5%. Conclusion： Chelator EDTA was quickly able to remove inorganic salt precipitate in medium and eliminating the interference of precipitate on bacterial growth determination. A relatively reliable, accurate and precise method used to measure bacterial optical density in precipitate-containing liquid medium was proposed.

关 键 词：EDTA 沉淀物 生长量测定 嗜有机甲基杆菌 

分 类 号：Q819[生物学—生物工程]