Explain Wright's tube
The anaerobic condition in Wright's tube is created using pyrogallol and NaOH. In the presence of NaOH, pyrogallol is oxidized and removes O2 very effectively in the process. After the anaerobic bacterium has been streaked out on the surface of the agar slant , a cotton plug is trimmed and then pushed into the culture tube until it rests just above the the top of the slant. The space between the top of the cotton plug anbd the open end of the culture tube is then filled with pyrogallol crystals, and 1 mL of 10% NaOH is added. the tube is closed iwth a rubber stopper and is immediately inverted. It is incubated upside down.