Isolation and identification of Polyhydroxybutyrate (PHB)-producing microorganisms from various sources in North Sinai

Abstract

The amount of non-biodegradable plastic waste on our planet is enormous. Natural materials like biomaterials are among the finest replacements for manmade plastics. In order to assist microorganisms resist severe environments, certain microbes generate bioplastics, which are lipid polyesters that build up as storage materials. The primary goal of this investigation was to isolate and characterize cultivable bacteria and fungi capable of producing bioplastics from North Sinai from different sources, such as saline soil, olive pomace, landfills, and seawater. Seven bacterial and five fungal isolates were selected from a total of 108 isolates to assay for PHB production and the selected isolates were stained with Sudan Black B for PHB formation, while Nile Blue A staining was used to detect the presence of PHA granules. All promising bacterial isolates with the highest PHB accumulation were identified as Halomonas, Lysinibacillus , Mesobacillus, Paracoccus, Paraliobacillus, Glutamicibacter, and Aquamicrobium ; most fungal isolates were yeasts, identified as Rhodotorula, Hortaea, Meyerozyma, and Sarocladium by morphological and biochemical characterization and confirmed by molecular techniques.