Isolation and identification of locally produce polyhydroxy butyrate from animal manure using scanning electron microscopy

Abstract

Polyhydroxy butyrate (PHB) is a biocompatible and biodegradable thermoplastic polymer. It is accumulated as granules in the cytoplasm of some kinds of bacteria that called PHB-producing bacteria. PHB is a polyester and used in bone implant materials. This study intended at the isolation, production, and identification of the PHB from PHB-producing bacteria isolated from animal manure. Additionally, to identify the extracted PHB using physical and chemical methods and investigate its surface features and porosity using scanning electron microscopy. Animal manure samples were collected from animal farms in AL-Muthanna province for isolation of PHB-producing bacteria. The isolated bacteria were identified using morphological and biochemical tests. Later on, the bacteria were cultured in special media for the production of PHB. The isolated PHP was identified using physical and biochemical tests. Moreover, the surface properties and porosity were investigated using a scanning electron microscope. In this study, a pure culture of PHB-producing bacteria was identified from animal manure. The identified bacteria were recognized as Bacillus spp. according to colony morphology, Gram stain, and biochemical tests. The extracted PHB was revealed typical physical and chemical features of the standard commercial PHB. Under scanning electron microscopy, the PHB surface revealed well distribute pores ranged in size from 0.2 to 20 µm and extended deeply in the depth of the structure. In conclusion, this study approved the production and identification of PHB from PHB- producing bacteria isolated from animal manure. The characterization of the PHB was compatible with standard commercial PHB. The authors recommend doing more other studies to use the animal waste manure to produce biological value polymer such as PHB from waste material.