Whole cell immobilization matrices
Mini review- Whole cell immobilization matrices
Introduction
The development of immobilization technique has offered sustainability and a better, greener approach in the production of metabolites for bioprocess in several industries. Examples of application of immobilization include wastewater treatment, as well as various applications in the drug and pharmaceutical industry3,8. Cell entrapment is one of the most common immobilization techniques used, whereby a porous polymeric matrix encloses the microbial cells, allowing the diffusion of substrates and products11.
Many papers have been published on the immobilization of enzyme. However, scientists have recently shifted their focus onto whole cell biocatalyst immobilization3. It has been shown that this technique is more beneficial in the long run when compared to enzyme immobilization. Each individual whole cell operates like a mini-reactor. They can regenerate essential cofactors from cheap hydrogen-donor substrates by utilizing their internal metabolism10. This offers stability, ability to regenerate cofactors, reusability and ease of solid-liquid separation. Individual researchers have performed whole cell immobilization on Streptomyces griseus, Microbacterium liquefaciens, Bacillus sp., Pseudomonas and serratia marcescens, a possible indication that this technique is as capable as the enzyme immobilization7. Furthermore, whole cell immobilization technique protects immobilized cells against potentially toxic substrate by entrapping them in gel beads6.
Suitable immobilization matrices are crucial to support the microorganisms in a successful application. Appropriate matrices must meet certain requirements, such as low cost, high cell viability, resistance to toxicity and durability. Several natural matrices (agar, agarose, alginate) and synthetic polymeric matrices (polyacrylamide and polyurethane) have been described in previous researches for the use of whole cell immobilization, with
Introduction
The development of immobilization technique has offered sustainability and a better, greener approach in the production of metabolites for bioprocess in several industries. Examples of application of immobilization include wastewater treatment, as well as various applications in the drug and pharmaceutical industry3,8. Cell entrapment is one of the most common immobilization techniques used, whereby a porous polymeric matrix encloses the microbial cells, allowing the diffusion of substrates and products11.
Many papers have been published on the immobilization of enzyme. However, scientists have recently shifted their focus onto whole cell biocatalyst immobilization3. It has been shown that this technique is more beneficial in the long run when compared to enzyme immobilization. Each individual whole cell operates like a mini-reactor. They can regenerate essential cofactors from cheap hydrogen-donor substrates by utilizing their internal metabolism10. This offers stability, ability to regenerate cofactors, reusability and ease of solid-liquid separation. Individual researchers have performed whole cell immobilization on Streptomyces griseus, Microbacterium liquefaciens, Bacillus sp., Pseudomonas and serratia marcescens, a possible indication that this technique is as capable as the enzyme immobilization7. Furthermore, whole cell immobilization technique protects immobilized cells against potentially toxic substrate by entrapping them in gel beads6.
Suitable immobilization matrices are crucial to support the microorganisms in a successful application. Appropriate matrices must meet certain requirements, such as low cost, high cell viability, resistance to toxicity and durability. Several natural matrices (agar, agarose, alginate) and synthetic polymeric matrices (polyacrylamide and polyurethane) have been described in previous researches for the use of whole cell immobilization, with