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微生物培养基使用中常出现的问题汇总

放大字体 缩小字体 发布日期:2020-01-07 11:31:48 来源:互联网

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">工作中发现,有部分检验员对培养基的使用存在障碍,借此机会和大家分享讨论一下大家常见的对培养基存在的一些疑问。


 

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">1、培养基煮沸溶解后再高压灭菌,还是直接高压灭菌存在疑惑。

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">拿麦康凯琼脂举个例子,溶解后灭菌,平板上没有不溶的结晶紫,没有紫色的斑点;相对比未溶解灭菌的,平板上有结晶紫和紫色的斑点。portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; color: rgb(241,136,35); padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">所以正确的做法是先煮沸溶解后再高压灭菌。

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px"> 

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">2、培养基PH值为什么不在标准范围内?

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; color: rgb(241,136,35); padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">其实出现这个情况的问题有很多种,大致我分为这么6大点:

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①质量不好(生产厂家出厂时portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">pH就不正确);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②灭菌问题(高压灭菌温度过高或灭菌时间过长,导致葡萄糖类焦化从而portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">pH降低);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">③保存时间(超过保质期或结块);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">④水质出现问题(可以用去离子水、纯化水、蒸馏水不能用矿泉水、自来水);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">⑤保存温度(保存温度过高);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">⑥光线直射总结本人认为以上6点都可能导致培养基portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">pH出现偏差,如果出现此类问题,建议逐一排查,直到问题解决。

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px"> 

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">3、培养基高压灭菌时为什么会焦化?

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; color: rgb(241,136,35); padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">不少检验人员在实验时,发现经过灭菌的培养基有焦化现象,我认为引起此现象的主要原因有以下4点:

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①可能你灭菌的时候温度超过了121℃(正常115-116℃20min即可);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②灭菌时间过长;

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">③培养基在容器中装的太多(不要超过容器容量的80%);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">④灭完菌的培养基在高温环境中保存的时间过长,这些都会导致培养基发生焦化现象。

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px"> 

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">4、培养基PH怎么测定?

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; color: rgb(241,136,35); padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">通常分两种情况:

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①对于无需高压灭菌的培养基,先煮沸溶解后再冷却至25℃时,测定其portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">pH值(固体培养基至少测2个点,取其平均值);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②对于需要高压灭菌的培养基,高压灭菌后,冷却至25℃测其pH(固体培养基至少测2个点,取其平均值)。

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px"> 

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">5、含琼脂培养基在倒平板为什么有时候不凝固或凝固不好?

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; color: rgb(241,136,35); padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">针对以上情况,我做了分析:

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①针对需要高压灭菌的培养基,倒平板时候要先摇匀(因为琼脂分子量比较大,在冷却过程中容易沉淀到底部,导致琼脂分散不均匀);

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②针对无需高压灭菌的培养基,一次煮沸溶解后不能直接倒平板,应重复煮沸溶解3-5次(因为一次不能确保琼脂完全溶解)。

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px"> 

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">6、为什么同一品牌的不同批号,粉末颜色有差别?

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; color: rgb(241,136,35); padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">分析可能有3个原因:

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①此培养基成分含有染料或指示剂;

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②不同批次粉末培养基含水量不同,一般要求≤6%,含水量越高,颜色越深;

portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">③加工时球磨时间越长颜色越深。

 

portant; font-size: 12px; word-wrap: break-word !important; max-width: ; font-family: 黑体; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">文章来源食品论坛网友分享,转载仅为知识分享

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