Isolation, identification of mesophiles and thermophiles from landfills in Can Tho city, Vietnam and their application for bio waste treatment

Abstract

Eighty-three isolates were isolated from two landfills in Can Tho city, Vietnam among 55 mesophiles and 18 thermophiles with 23, 25 and 35 amylolytic, cellulolytic and proteolytic isolates, respectively. Based on enzymatic activity, 4/83 isolates were chosen to identify with universal primers 8F and 1492R. The sequences from selected bacteria showed high degrees of similarity to those of the GenBank references strains (between 97% to 99%) with Burkholderia cenocepacia strain A4 (99% identity)[thermophilic and amylolytic strain], Bacillus licheniformis strain C2 (99% identity)[mesophilic and cellulolytic strain], Azospirillum amazonense strain P1 (98% identity)[mesophilic and proteolytic strain] and Acinetobacter radioresistens strain P4 (99% identity)[thermophilic and proteolytic strain]. pH of the compost was around 4.4 – 6.2 and temperature only got approximately 40oC to 50oC. All of them make proper anaerobic progress, so the population of mesophilic strains exceeded that of thermophiles. Meanwhile, the treatment of meso+thermophiles with a mixture of the six strains helped the highest rate of lost waste weight (10.18%). Therefore, application of these bacterial strains offers a promising approach for bio-waste treatment in tropical households or even landfills.