What is your substrate, please?

Best regards

Vit

It is organic waste,which includes almost everything from dry leaves to kitchen,market,fruit waste

1. Sterilize the medium (121C, 20-30 min);

2. Check A. niger culture for contamination;

3. Inoculate in aseptic conditions;

4. Carry out the fermentation in aseptic conditions....

Good luck!

The recommendation of Dr. Majid Alipour Mamaqani

Vit

The recommendation of Dr. Vassilev is OK, but from practical point of view, it is cost limiting.

Soory for above answer, it was a mistake.

Best regards

Vit

Sterilise the solid substrate at 121 degree for 20 to 30 min.

Properly Sterilise the inculcating loop or cork boarer before inoculation

Autoclave the moistened solid medium for 40 min.

Study under aseptic conditions.

Carry out only solid media work in the incubator.

In solid media studies, the risk of contamination is very low, since water is too low. If you study under aseptic conditions, no contamination occur.

I agree with professor Vassilev

I wonder how to manage contamination in tray bioreactors. Should the medium be sterilized in situ or...?

In addition to what Professor Vassilev recommends, I propose to:

1- Take a look on the quality of the strain used to inoculate the culture.

2- Try increasing the concentration of the inoculation in order to help the strain to be better established.

3- Try to establish a more favorable water activity for this strain. This could give more favorable conditions to the strain to compete against the infection strains.

4- If using forced aeration try to test the quality of the air filter or system used to sterilize the air.

5- Look for a growth medium composition more favorable to this strain.

Water content is very important in solid substrate fermentation. Since the amount of water only moistens the substrate, the risk of contamination with bacteria and yeasts is reduced. If sterile conditions are also taken seriously, the possibility of contamination is minimized. Good evening