METHODS OF BACTERIAL CULTURE MAINTENANCE

 Methods of bacterial culture maintenance :-

What is bacteria :- 

Bacteria, also called germs, are microscopic organisms not visible with the naked eye. 

Bacteria are a type of biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometers in length, bacteria have a number of shapes, ranging from spheres to rods and spirals.

What is bacterial culture :- 

A bacterial culture is a test used to determine whether bacteria or fungi are infecting a wound. 

Bacterial cultures are typically collected from infected (or potentially infected) tissue, but can also be taken from. 

What is maintenance of culture?

Maintenance culture is the values, way of thinking, behaviour, perception, and the underlying assumptions of any person or group or society that considers maintenance as a matter that is important (priority) and practices it in their life. 

 These cultures are not easy to develop.

How to maintain bacterial culture :- 

There are several method for it as following -

1) Periodic transfer to fresh media 

2) Preservation by overlaying culture with mineral oil

3) Freeze drying (lyophilization )

4 ) Storage at low temperature 

1) Periodic transfer to fresh media :--

Strains can be maintained by periodically preparing a fresh culture from the previous stock culture.

 The culture medium, the storage temperature, and the time interval at which the transfers are made vary with the species and must be ascertained beforehand.

The temperature and the type of medium should support slow rather than rapid growth so that time interval between transfer can be used as long as possible , by the method culture viable for several week or month .

2) Preservation by overlying culture with mineral oil :- 

The bacteria can be successfully preserved by covering the growth on agar slant with sterile mineral oil .

The oil must cover slant completely the viability under treatment varies with species up to 1 month to 2 year .

3) freeze drying :-

In this process the dense cell suspension culture is placed in small vials and frozen at - 60 degree celsius to - 80 degree celsius .

This vials connect to high vaccum line the ice present in the frozen suspension subline under vaccum .

This result dehydration of bacteria with minimum of damage to delicate cell structure .

4) Storage at low temperature :- 

The cell are prepared as dense suspension in media contain cryprotective agent such as DMSO or glycerol .

The cell suspension stored at - 150 degree celsius in liquid nitrogen .