Luminescent bacteria can be stored as standard glycerol stab cultures.
This is the method of preparing glycerol stab cultures of bacteria:
In the sterile plastic tube mix 0,15 ml sterilised glycerol and 0,85 ml liquid culture of luminescent bacteria
Shake the mixture well
The mixture should be frozen immediately using liquid nitrogen
Store the cultures in the temperature of -70°C
Cultivation of Luminescent Bacteria
Cultivation of luminous bacteria is processed on the special medium "BOSS"
This is the method of preparation the medium "BOSS":
30 g NaCl
1 g Glycerol
10 g Peptone (Bacto-Peptone)
3 g Beef Extract
(to obtain solid medium you should add 15 g of Bacto-Agar)
Dilute the ingredients in water (pH should be about 7,3)
Fill with H2O up till 1000 ml
The cultivation should be conducted in temperature 18 - 22°C. Liquid cultures should be well aerated (the aeration pumps may be used or cultures should be shaken well). It is necessary to support sufficient amount of oxygen needed in luminescence reactions.
On solid medium the most intensive glowing can be observed 1 - 5 days after inoculation but faint glowing can be observed longer (even some weeks). Big differences between different species of luminescent bacteria can be observed here (from my observation it occured that the shortest time of glowing have the luminescent bacterium - Vibrio harveyi).
Use of Luminescent Bacteria for Determining Toxicity in Aquatic Environments
A simple rapid method for monitoring the toxicity of aquatic samples has been developed. The assay is based on changes in the light output of luminescent bacteria, as measured in a photometric device. Under suitable conditions, selected strains of luminescent bacteria emit a constant amount of light as a metabolic by-product. On exposure to toxicants, the light intensity is quickly diminished by an amount which is proportional to the concentration of the toxicant. An initial comparison of this new method with a 96-h acute fish toxicity test suggests that the bacterial test compares favorably in sensitivity with other tests while being more simple and rapid to perform. Data can be obtained in two to five minutes. Some examples of demonstrated sensitivities (in mg/litre) are: pentachlorophenol, 0.005; carbon tetrachloride, 6.0; sodium lauryl sulfate, 1.0; chlordane, 0.6; and sodium hypochlorite, 0.005.
أتمنى اني أكون جاوبت جواب كافي