Isolation and characterization of potential multiple extracellular enzyme-producing bacteria from waste dumping area in Addis Ababa

Abstract

Extremozymes are innovative and robust biocatalysts produced by various microorganisms from harsh environments. As thermophilic organisms can only develop in a few places, studying them in geothermal environments has provided new insights into the origins and evolution of early life and access to significant bio-resources with potential biotechnology applications. The work aimed to isolate and identify likely multiple extracellular enzyme-producing thermophilic bacteria from an Addis Ababa landfill (Qoshe). The streaking approach was used to purify 102 isolates acquired by serial dilution and spread plate method. The isolates were morphologically and biochemically characterized. Thirty-five cellulases, 22 amylase, 17 protease, and nine lipase-producing bacteria were identified using primary screening methods. Further secondary screening using Strain safety evaluation; two bacterial strains (TQ11 and TQ46) were identified. Based on morphological and biochemical tests, they were found to be gram-positive and rod-shaped. Furthermore, molecular identification and phylogenic analysis of selected promising isolates confirmed the identity of the isolates, Paenibacillus dendritiformis (TQ11) and Anoxybacillus flavithermus (TQ46). The results indicated that, multiple extracellular enzyme-producing thermophilic bacteria isolated from a waste dumping area in Addis Ababa offer useful features for environmental sustainability in a wide range of industrial applications due to their biodegradability and specialized stability under extreme conditions, increased raw material utilization, and decreased waste.

Keywords

• Paenibacillus dendritiformis
• Anoxybacillus flavithermus
• Thermophilic bacteria
• Thermophiles
• Extracellular enzyme
• Waste dumping area