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厌氧菌的培养方法
厌氧菌在有氧的情况下不能生长。要培养厌氧菌，必须创造一个无氧的环境。通常用培养基中加入还原剂，或用物理、化学方法去除环境中的游离氧，以降低氧化还原电势。如疱肉培养基、硫基乙酸钠培养基，牛心脑浸液培养基等。常用的厌氧培养方法有许多，可根据实际情况选用。
1．厌氧缸法接种好标本的平板或液体培养基试管，可放入厌氧缸内培养，厌氧缸是普通的干燥缸，用物理化学的方法使缸内造成厌氧环境，从而将厌氧菌培养出来。
2．厌氧袋（Bio-bag）即在塑料袋内造成厌氧环境来培养厌氧菌。塑料袋透明而不透气，内装气体发生管（有硼氢化钠的碳酸氢钠固体以及5%柠檬酸安瓿）、美兰指示剂管、钯催化剂管、干燥剂。放入已接种好的平板后，尽量挤出袋内空气，然后密封袋口。先折断气体发生管，后折断美兰指示剂管，命名袋内在半小时内造成无气环境。如不突变表示袋内已达厌氧状态，可以孵育。
3．厌氧手套箱（Anaerobie glove box）是迄今为止国际上公认的培养厌氧菌最佳仪器之一。它是一个密闭的大型金属箱，箱的前面有一个有机玻璃做的透明面板，板上装有两个手套，可通过手套在箱内进行操作，故名。箱侧有一交换室，具有内外二门，内门通箱内先关着。欲放物入箱，先打开外门，放入交换室，关上外门进行抽气和换气（H2，CO2，N2）达到厌氧状态，然后手伸入手套把交换室内门打开，将物品移入箱内，关上内门。箱内保持厌氧状态，也是利用充气中的氢在钯的催化下和箱中钱残余氧化合成水的原理。该箱可调节温度，本身是孵箱或孵箱即附在其内，还可放入解剖显微镜便于观察厌氧菌菌落，这种厌氧箱适于作厌氧细菌的大量培养研究，大量培养基可放入作预还原和厌氧性无菌试验。金属硬壁型厌氧箱的抽气、充气、厌氧环境和温度等均系自动调节。
4.厌氧盒：原理同厌氧袋，有成品销售。
5.生物耗氧法：在一密闭的容器内放以生物（多是植物），消耗氧气，同时产生二氧化碳，供细菌生长用。我没见过。
6.焦性末食子酸法：在一洁净的玻片上铺上纱布或滤纸，均匀撒上焦性末食子酸，然后再混入NaHCO3粉末或NaOH溶液，迅速将已接种细菌的平板倒扣在上面，用融化的白蜡封边，造成一个封闭空间。焦性末食子酸与碱反应后耗氧。该法用于厌氧不严格的厌氧菌的培养，简单。如有梭状芽孢杆菌。
7.疱肉培养基：本身就是一个不需特殊设备的厌氧培养法。疱肉和肉汤装入大试管，液面封凡士林，造成无氧环境。
The “Hungate” Method
Clostridium cellobioparum occurred in numbers too small for it to be considered important in the rumen. Further study was necessary to demonstrate the major predominant cellulolytic bacteria in the rumen. Difficulty in seeing the clearings in the cellulose in agar shake tubes led him to use roller tubes. His method was simply to mechanically roll the tube horizontally in shallow cold water as the agar solidified. This gave a homogenous thin layer of solidified agar medium on the inner surface of anaerobic tubes. By this method, the bacterial colonies were kept separated and the shape, size and color could be observed easily. Cellulolytic ones gave a clearing if cellulose powder was included in the medium. Anaerobiosis was also carefully observed. Since the rumen atmosphere contained 70% CO2; a CO2 atmosphere and 0.5% NAHCO3 was selected as the chief buffer. This necessitated flushing of culture tubes with O2-free CO2. Initially this was achieved by bubbling through a chromous acid solution. Later the O2-free CO2 was achieved by passing CO2 from the regular CO2 tank through a hot copper column reduced with hydrogen. After the tubes were filled with media, they were closed with black rubber stoppers, which were impermeable to gases. A typical medium usually contained three parts: one-third balanced salt solution, one-third rumen fluid and one-third suspension of substrates which could be HCL-treated absorbent cotton, or later Whatman no.1 filter paper, wet ground in a pebble mill to obtain a fine suspension. Of course, oxygen had to be excluded and also, later, a reducing agent such as cysteine or sodium sulfide was added to help reduce any residue of oxygen and make the media chemically ‘reduced.’ With the availability of the Hungate method, many anaerobic bacteria including cellulolytic ones such as Bacteroides succinogenes and Micromonospora propionici from the rumen were isolated and studied. This technique was spread to other laboratories, and over the years scientists from many different countries came to Hungate’s laboratory to study anaerobic bacteria.
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