亚洲人成电影在线观看青青_日本中文一二区有码在线_欧美乱码伦视频_久久综合日本久久综合

簡述培養(yǎng)基制備的要求

發(fā)布時(shí)間:

2022-12-27

作者:

模擬灌裝用培養(yǎng)基


使用脫水培養(yǎng)基和其他含有有害物質(zhì)(膽鹽或其它選擇劑)的成分時(shí),應(yīng)遵守良好實(shí)驗(yàn)室規(guī)范和生產(chǎn)廠商提供的使用說明配制。如質(zhì)量/體積、pH、制備條件、滅菌條件和操作步驟等,并做好記錄。

配制培養(yǎng)基使用蒸餾水或相同質(zhì)量的水,以排除測(cè)試條件下抑制或影響微生物生長的物制。如果蒸餾水的用氯消毒的水制備的,在蒸餾前應(yīng)先對(duì)氯進(jìn)行中和(見GB/T6682)。盛放蒸餾水的容器最好是由中性材料制成的(如中性玻璃、聚乙烯等)。在初次使用前要確認(rèn)容器中不含任何抑制因子。

為保證蒸餾水的質(zhì)量,電阻率應(yīng)至少達(dá)到300000Ωcm。

警告:采用離子交換器(去離子)生產(chǎn)的去離子水,微生物含量較高,這種水在過濾滅菌后仍可能帶有細(xì)菌生長的抑制因子。所以配置培養(yǎng)基時(shí)最好不要使用這種方法生產(chǎn)的去離子水而應(yīng)使用蒸餾水。

稱量和復(fù)水

稱量所需的脫水培養(yǎng)基(注意緩慢操作,必要時(shí)佩帶口罩或在通風(fēng)柜中操作,以防吸入含有毒物質(zhì)的培養(yǎng)基粉末),先加入少量的水,充分混合(注意避免培養(yǎng)基結(jié)塊),然后再加入至所需的量。

溶解

脫水培養(yǎng)基加水后適當(dāng)加熱,并不停攪拌使其快速溶解,必要時(shí),重新溶解。含瓊脂的培養(yǎng)基在加熱前應(yīng)先浸泡幾分鐘。用各別成分制備的培養(yǎng)基應(yīng)將不同成分分別加入適量的水中,并充分溶解,然后再加入到所需的量。

pH值的測(cè)定和調(diào)整

用pH計(jì)測(cè)pH,必要時(shí)進(jìn)行調(diào)整。在實(shí)驗(yàn)室用各別成分制備培養(yǎng)基,除特殊說明外,培養(yǎng)基滅菌后冷卻到25℃時(shí),pH的變化不應(yīng)超過0.2個(gè)單位。一般使用濃度約為40g/L(約1mol/L)的氫氧化鈉溶液或濃度為36.5g/L(約1mol/L)的鹽酸溶液調(diào)整培養(yǎng)基的pH。

注:商品化的培養(yǎng)基高壓滅菌后pH值可能變化很大,但采用優(yōu)質(zhì)蒸餾水或去離子水配配制時(shí),滅菌前無需調(diào)節(jié)pH值。

分裝

將制配制好的培養(yǎng)基分裝到適當(dāng)?shù)娜萜髦?,根?jù)不同用途,容器的體積可為培養(yǎng)基的1倍、2倍或3倍。

滅菌

培養(yǎng)基和試劑應(yīng)采用濕熱滅菌或過濾滅菌。亮綠培養(yǎng)基等特定的培養(yǎng)基中含有對(duì)光和熱敏感的物質(zhì),只能煮沸滅菌。煮沸后應(yīng)迅速冷卻,避光保存(參見相關(guān)標(biāo)準(zhǔn)或供應(yīng)商使用說明)。

 

 


The use of dehydrated medium and other ingredients containing harmful substances (bile salts or other alternatives) shall be subject to good laboratory specifications and instructions provided by the manufacturer. Such as quality/volume, pH, preparation conditions, sterilization conditions and operation steps, etc., and keep records.
water
 
The preparation medium USES distilled water or the same quality of water to eliminate or influence microbial growth under test conditions. If the distilled water is prepared by chlorine disinfection, the chlorine should be neutralized before distillation (see GB/T6682). Containers of distilled water are best made from neutral materials (such as neutral glass, polyethylene, etc.). Make sure the container does not contain any inhibiting factors prior to initial use.
 
To ensure the quality of distilled water, resistivity should be at least 300000 Ω cm.
Warning: ionized water produced by ion exchangers (deionized) is high in microbial content. This water may still contain the inhibitory factor of bacterial growth after filtration and sterilization. Therefore, it is best not to use this method to produce deionized water when the medium is used, and distilled water should be used.
Weigh and rehydrate.
 
Weighing the dehydrated medium (note that slow operation, wearing masks or in ventilation cabinet operation when necessary, to prevent inhalation of toxic medium powder), add a small amount of water first, mix (avoid medium agglomeration), then add to the amount required.
dissolve
 
After adding water to the dehydrated medium, heat it properly and do not stop stirring to dissolve it quickly. When necessary, redissolve it. AGAR AGAR medium should be soaked for a few minutes before heating. The culture medium prepared by each component should be added to the appropriate amount of water and dissolved, and then added to the desired amount.
 
Determination and adjustment of pH value.
PH meter is used to measure pH and adjust when necessary. Culture medium preparation from individual components in the lab, except where noted, culture medium after sterilization cooling to 25 ℃, the pH change should not be more than 0.2 units. The pH of the medium with a concentration of approximately 40g/L (about 1mol/L) or concentration of 36.5g/L (about 1mol/L) of hydrochloric acid solution was used.
Note: the pH value may vary greatly after the commercialized medium high pressure sterilization, but the pH value should not be adjusted before sterilization with high quality distilled water or deionized water distribution.
Partial shipments
 
The prepared medium is divided into suitable containers, and the volume of the container can be 1, 2, or 3 times that of the medium according to different USES.
 
sterilization
 
The medium and reagent should be sterilized or sterilized by wet heat. A specific medium, such as a bright green medium, contains substances that are sensitive to light and heat, and can only be boiled and sterilized. After boiling, it should be cooled quickly to avoid light preservation (see related standards or supplier instructions).