摘要
建立微孔板式微生物法检测乳粉中叶酸的快速方法。筛选不同品牌和型号微孔板,基于微生物法的原理,样品提取液和标准品工作液,在聚苯乙烯材质的96孔微孔板中直接梯度稀释。测定用培养基中加入0.3%的菌悬液,混匀后分配到含有样品和标准品的微孔中,培养22 h后用酶标仪测定吸光度值。结果表明各种规格的聚苯乙烯微孔板均适用本实验。本方法标准曲线相关系数0.9997,叶酸质量浓度在30,60,120μg/100g和240μg/100g添加水平的回收率为96.5%~104%,相对标准偏差在1.60%~4.27%之间,国标GB 5009.211-2014相比,检测结果无显著性差异(P>0.05)。该方法操作简单、培养时间短、结果稳定、准确、通量大,适合检测乳粉中叶酸的含量。
To establish a rapid microporous plate microbiological method for the determination of folic acid in milk powder. Screening different brands and models of microplates,based on the principle of microbiological method,the sample extract and standard working solution were directly diluted in a 96-well microporous plate made of polystyrene. 0.3% bacterial suspension was added to the culture medium,mixed and distributed to the micropores containing samples and standard substances. After 22 h of culture,the absorbance value was measured with a microplate analyzer. All kinds of polystyrene microporous plates are suitable for this experiment. The standard curve correlation coefficient of this method was 0.9997. The recoveries of folic acid at 30,60,120 and 240μg/100 g supplemental levels were 96.5%-104%,and the relative standard deviations were 1.60%-4.27%. Compared with GB 5009.211-2014,the detection results showed no significant difference(P>0.05). The method is simple operation,short detection time,stable result,accurate,large flux,suitable for detection of folic acid content in the milk powder.
作者
王晶
林泽栋
李艳
薛晓晶
WANG Jing;LIN Zedong;LI Yan;XUE Xiaojing(CAIQTEST(Beijing)Co.Ltd.,Beijing 100123,China;Chinese Academy of Inspection and Quarantine Compre-hensive Test Center,Beijing 100123,China)
出处
《中国乳品工业》
CAS
北大核心
2021年第11期50-53,共4页
China Dairy Industry
基金
中国检验检疫科学研究院基本科研业务费项目(2020JK038)。
关键词
叶酸
微孔板
微生物
乳粉
folic acid
micro plate
microbiological
milk powder
