portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">portant; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">工作中發(fā)現(xiàn),有部分檢驗(yàn)員對(duì)培養(yǎng)基的使用存在障礙,借此機(jī)會(huì)和大家分享討論一下大家常見的對(duì)培養(yǎng)基存在的一些疑問。
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">1、培養(yǎng)基煮沸溶解后再高壓滅菌,還是直接高壓滅菌存在疑惑。
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">拿麥康凱瓊脂舉個(gè)例子,溶解后滅菌,平板上沒有不溶的結(jié)晶紫,沒有紫色的斑點(diǎn);相對(duì)比未溶解滅菌的,平板上有結(jié)晶紫和紫色的斑點(diǎn)。portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">所以正確的做法是先煮沸溶解后再高壓滅菌。
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">2、培養(yǎng)基PH值為什么不在標(biāo)準(zhǔn)范圍內(nèi)?
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">其實(shí)出現(xiàn)這個(gè)情況的問題有很多種,大致我分為這么6大點(diǎn):
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①質(zhì)量不好(生產(chǎn)廠家出廠時(shí)portant; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">pH就不正確);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②滅菌問題(高壓滅菌溫度過高或滅菌時(shí)間過長(zhǎng),導(dǎo)致葡萄糖類焦化從而portant; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">③保存時(shí)間(超過保質(zhì)期或結(jié)塊);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">④水質(zhì)出現(xiàn)問題(可以用去離子水、純化水、蒸餾水不能用礦泉水、自來水);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">⑤保存溫度(保存溫度過高);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">⑥光線直射總結(jié)本人認(rèn)為以上6點(diǎn)都可能導(dǎo)致培養(yǎng)基portant; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">pH出現(xiàn)偏差,如果出現(xiàn)此類問題,建議逐一排查,直到問題解決。
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">3、培養(yǎng)基高壓滅菌時(shí)為什么會(huì)焦化?
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">不少檢驗(yàn)人員在實(shí)驗(yàn)時(shí),發(fā)現(xiàn)經(jīng)過滅菌的培養(yǎng)基有焦化現(xiàn)象,我認(rèn)為引起此現(xiàn)象的主要原因有以下4點(diǎn):
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①可能你滅菌的時(shí)候溫度超過了121℃(正常115-116℃20min即可);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②滅菌時(shí)間過長(zhǎng);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">③培養(yǎng)基在容器中裝的太多(不要超過容器容量的80%);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">④滅完菌的培養(yǎng)基在高溫環(huán)境中保存的時(shí)間過長(zhǎng),這些都會(huì)導(dǎo)致培養(yǎng)基發(fā)生焦化現(xiàn)象。
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">4、培養(yǎng)基PH怎么測(cè)定?
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">通常分兩種情況:
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①對(duì)于無需高壓滅菌的培養(yǎng)基,先煮沸溶解后再冷卻至25℃時(shí),測(cè)定其portant; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">pH值(固體培養(yǎng)基至少測(cè)2個(gè)點(diǎn),取其平均值);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②對(duì)于需要高壓滅菌的培養(yǎng)基,高壓滅菌后,冷卻至25℃測(cè)其pH(固體培養(yǎng)基至少測(cè)2個(gè)點(diǎn),取其平均值)。
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">5、含瓊脂培養(yǎng)基在倒平板為什么有時(shí)候不凝固或凝固不好?
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">針對(duì)以上情況,我做了分析:
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①針對(duì)需要高壓滅菌的培養(yǎng)基,倒平板時(shí)候要先搖勻(因?yàn)榄傊肿恿勘容^大,在冷卻過程中容易沉淀到底部,導(dǎo)致瓊脂分散不均勻);
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②針對(duì)無需高壓滅菌的培養(yǎng)基,一次煮沸溶解后不能直接倒平板,應(yīng)重復(fù)煮沸溶解3-5次(因?yàn)橐淮尾荒艽_保瓊脂完全溶解)。
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">6、為什么同一品牌的不同批號(hào),粉末顏色有差別?
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; 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: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">分析可能有3個(gè)原因:
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">①此培養(yǎng)基成分含有染料或指示劑;
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">②不同批次粉末培養(yǎng)基含水量不同,一般要求≤6%,含水量越高,顏色越深;
portant; font-size: 16px; word-wrap: break-word !important; max-width: ; font-family: 宋體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; letter-spacing: 0px; padding-right: 0px">③加工時(shí)球磨時(shí)間越長(zhǎng)顏色越深。
portant; font-size: 12px; word-wrap: break-word !important; max-width: ; font-family: 黑體; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; padding-right: 0px">文章來源食品論壇網(wǎng)友分享,轉(zhuǎn)載僅為知識(shí)分享