Monitoring the growth, survival and phenol utilization of the fluorescent-tagged Pseudomonas oleovorans immobilized and free cells

Abstract

Bioaugmentation in wastewater treatment plants (WWTPs) is challenging due to low survival and persistence of applied microbes. This study aimed to track the capacity and survival of fluorescent-tagged Pseudomonas oleovoransICTN13 as a model organism applicable in bioaugmentation of phenol-containing wastewater. The isolate was immobilized in alginate biopolymer, and enhanced efficacy and survival for biodegradation of phenol against free cells were studied. Encapsulated cells resulted in enhanced phenol removal efficiency (~94%) compared to free cells (~72%). Encapsulation of cells facilitated an extended storage time of 30 days. Remarkably, phenol and COD removal efficacy of encapsulated cells was sustained up to ~ 92-93% in a reactor after 45 days, while free cells could produce ~ 80-84% removal efficiency. Fluorescence microscopy showed high survival of the encapsulated cells, whereas gradual deterioration of free cells was observed. Thus, the findings highlight the importance of bio augmented strain in WWTPs where encapsulation is a crucial factor.

Keywords: Bioaugmentation; Encapsulation; Phenol; Pseudomonas oleovorans.