革兰氏染色实验教学探讨

Explorement in Gram stain experiment teaching

革兰氏染色的结果受许多因素的影响,初做该实验的学生不易掌握。为更好地指导学生得到正确的实验结果,分别对菌龄、涂菌量和乙醇脱色等关键影响因素进行了探索。结果显示大肠杆菌革兰氏染色的最佳菌龄是10~24h,金黄色葡萄球菌是10~14h;两种菌的涂片菌量（厚度）为在直径0.5~1.0cm内涂1~2μL的涂片菌液;脱色时间是浸入酒精溶液中脱色20~30s。

Gram stain is affected by many factors, and it＇s result is not easy to master at the begining. In order to improve the teaching effectivmeness of Gram stain experiment, the influences of bacterium age, the thickness of microbe smear and the degree of ethanol decolouration on the result of Gram stain of bacterium are studied. The result shows that the right culture time of E. co li and staphylococus aureus in the nutrient culture time is between 10- 24h and 10 - 14h respectively. Smear should be even and thin. The time of decolorization is strictly controlled between 20 - 30s.