Improving the stability of bacteriocin extracted from Enterococcus faecium by immobilization onto cellulose nanocrystals

Carbohydr Polym. 2019 Apr 1:209:172-180. doi: 10.1016/j.carbpol.2019.01.027. Epub 2019 Jan 9.

Abstract

Enterococcus faecium (E. faecium) isolated from Vigna mungo (Black gram) produced bacteriocin that inhibits both Gram positive and Gram negative bacteria and better heat stability (100 °C for 30 min). The bacteriocin was sensitive to protease treatment and most active in acidic pH. Bacteriocin produced by Pediococcus acidilactici was used for comparison. To enhance stability for diversified applications, the bacteriocin was immobilized by physical adsorption onto cellulose nanocrystals (CNC) extracted from cotton linters. The bacteriocin immobilization yield was 64.91% for P. acidilactici and 53.63% for E. faecium. The bacteriocin immobilized CNC was characterized by DLS particle sizing, FTIR and AFM to evaluate size distribution, chemical nature and surface morphology. The bacteriocins immobilized on CNC showed 50% increase in stability in terms of antibacterial activity. The enzymatic synthesis of CNC in combination with physical adsorption immobilization method for bacteriocin makes it an efficient system of producing antibacterial nanofillers for food packaging and bio-composites applications.

Keywords: Antibacterial; Bacteriocin; Cellulose nanocrystals; Enterococcusfaecium; Immobilization; Vigna mungo.

MeSH terms

  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / isolation & purification
  • Anti-Bacterial Agents / metabolism
  • Anti-Bacterial Agents / pharmacology
  • Bacteriocins / chemistry*
  • Bacteriocins / isolation & purification
  • Bacteriocins / metabolism
  • Bacteriocins / pharmacology
  • Cellulose / chemistry*
  • Enterococcus faecium / chemistry*
  • Hydrogen-Ion Concentration
  • Immobilized Proteins / chemistry*
  • Immobilized Proteins / isolation & purification
  • Immobilized Proteins / metabolism
  • Immobilized Proteins / pharmacology
  • Microbial Sensitivity Tests
  • Nanoparticles / chemistry*
  • Particle Size
  • Protein Stability
  • Proteolysis
  • Sodium Chloride / chemistry
  • Temperature

Substances

  • Anti-Bacterial Agents
  • Bacteriocins
  • Immobilized Proteins
  • Sodium Chloride
  • Cellulose