探索7.5%氯化钠肉汤增菌液OD值与金黄色葡萄球菌生物量的关系  

Relationship of OD value and Staphylococcus aureus biomass in 7.5% sodium chloride broth

作　　者：李明阳 胡朋 高伟敏 刘天岩 何艳玲[2] LI Ming-Yang;HU Peng;GAO Wei-Min;LIU Tian-Yan;HE Yan-Ling(Beijing Landbridge Technology Co.,Ltd.,Beifing 1000123,China;Chinese Academy of Inspection and Quarantine, Beijing 1000123,China)

机构地区：[1]北京陆桥技术股份有限公司,北京市100123 [2]中国检验检疫科学研究院,北京市100123

出　　处：《食品安全质量检测学报》2019年第3期603-607,共5页Journal of Food Safety and Quality

摘　　要：目的通过OD值的测定,确定一种简单、快捷、准确的方法判定液体培养基的增菌效果。方法分别通过在200、350、470、550、660 nm 5种不同波长下测定培养基空白及增菌液OD值,选择550 nm作为实验测定波长。通过测定不同初始菌数、不同培养时间菌悬液550nm的OD值以及菌落总数,建立回归性方程。结果当OD值低于0.11时, 4株标准菌株的OD值均与菌落总数的对数值呈现正相关,且r^2>0.99。当OD值大于0.11时,菌悬液中含有菌落数均达到10~7以上,菌株不再以对数形式进行繁殖代谢,4株菌均呈现出线性相关性,且r^2>0.95。结论对于7.5%氯化钠肉汤培养基可选用550 nm的吸光值对培养基增菌效果进行判定,以得到一种更加准确、快速、高效的评价液体培养基质量的方法。Objective To develop a simple, fast and accurate method for determining the enrichment effect of the liquid medium through the determination of the OD value. Methods OD values of blank medium and bacteria increasing solution were determined at 5 wavelengths of 200, 350, 470, 550 and 660 nm, respectively, and 550 nm was selected as the experimental wavelength. The regression equations were established by measuring the OD values of 550 nm of bacterial suspension and the total number of bacterial colonies at different initial bacterial count s and culture time. Results When the OD value was lower than 0.11, the OD values of the four standard strains were positively correlated with the logarithm of the total numbers of colonies, and r^2>0.99. When the OD value was greater than 0.11, the number of colonies contained in the bacterial suspension reached 10~7 or more, and the strain was no longer reproductively metabolized in logarithmic form. All the 4 kinds of strains showed linear correlations, and r^2>0.95. Conclusion For 7.5% sodium chloride broth culture medium, the light absorption value of 550 nm can be used to determine the bacteria enhancement effect of the medium, so as to obtain a more accur ate, rapid and efficient method to evaluate the quality of liquid culture medium.

关 键 词：7.5%氯化钠肉汤 金黄色葡萄球菌 OD值 菌落总数 

分 类 号：TS251.1[轻工技术与工程—农产品加工及贮藏工程]