Sveriges lantbruksuniversitet
Swedish University of Agricultural Sciences
Sveriges lantbruksuniversitet
Swedish University of Agricultural Sciences

Institutionen för mikrobiologi

 
Sveriges lantbruksuniversitet
Swedish University of Agricultural Sciences

Microbial Formulation and Stabilization

 

 

 

 

 

The activities of the group is led by Associate Professor
Sebastian Håkansson 

Sebastian Håkansson
   
Biological and physical stabilization by formulating and often drying microorganisms is necessary to produce manageable, easily applied and storage-stable bio products. Even so, drying and storage will inevitably expose the microorganisms to environmental stress. The tolerance of the microorganisms to drying can be improved by optimizing the physiological state of the cells prior to desiccation. Two principal approaches can help to achieve this. The first one is to optimize the growth conditions with respect to medium composition and abiotic cultivation parameters so that maximum stress tolerance in stationary phase is obtained. The second approach is that of pre-conditioning or stressing the cells after cultivation through exposure to non-lethal environmental stressors. In other words, microorganisms can sometimes be trained to better cope with adverse conditions. Little stress results in increased fitness and better chances of surviving stress levels that would be lethal for a non-preconditioned cell.  
   
Biological adaptations alone are not sufficient to ensure high survival in dry biological products. Addition of compounds that provide outside protection from harmful effects of freezing or drying is also necessary. These additives are often substances that the microorganisms can produce themselves and use for protection inside, such as disaccharides, amino acids and various amino acid derivates. Production of these compounds is often a response to stress or pre-conditioning and by including these compounds in the formulation, survival can often be improved. However, each new microorganism will very likely require individual formulation optimization with regards to preconditioning regimes and formulations additives.
   

   
Below is a list of on-going and finished research projects
   
 CBC - Center for Biological Control  
   
The novel species Thorsellia anophelis - Towards a self-sustainable anti-malarial system in mosquitoes  
   
Stabilization of a Sphingobium species as a bioprophylaxis for pesticide degradation  
   
Development of new on-seed formualtions of rhizobacteria  
   
BACSIN - Bacterial Abiotic Stress and Survival Improvement Network  
   
Impact of biopolymers on biological and physico-chemical characteristics of technical powder containing freeze-dried microorganisms  
   
Freeze-drying and storage stability of Lactobacillus coryniformis Si3 in sucrose-based formulatons  
   
Dry and water-based stabilisation of the biocontrol yeast Pichia anomala  
   
Past and present members of the group  Now at...
   
Joakim Bjerketorp - Researcher  
Per Wessman - Post-Doc  
Åsa Begenholtz (Schoug) - Ph.D-student  
Mirela Jonson - Researcher  
Jens Levenfors - Researcher  
Lisa Fredlund - Post-Doc  
   
   
   
   
   
 
Sidan uppdaterad: 2012-10-31.
 

Fakulteten för naturresurser och lantbruksvetenskap • nlfak@slu.se  
Box 7082, 750 07 Uppsala • Tel. 018 67 10 00  •  Org.nr: 202100-2817